/* =====================
   CSS Variables & Reset
   ===================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-tertiary: #f1f5f9;
  --bg-card: #ffffff;
  --text-primary: #0f172a;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;
  --border-color: #e2e8f0;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --accent-light: #eff6ff;
  --success: #10b981;
  --success-light: #ecfdf5;
  --warning: #f59e0b;
  --warning-light: #fffbeb;
  --danger: #ef4444;
  --danger-light: #fef2f2;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 4px 12px rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --bg-card: #1e293b;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --border-color: #334155;
  --accent: #60a5fa;
  --accent-hover: #3b82f6;
  --accent-light: #1e3a5f;
  --success: #34d399;
  --success-light: #064e3b;
  --warning: #fbbf24;
  --warning-light: #78350f;
  --danger: #f87171;
  --danger-light: #7f1d1d;
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 4px 12px rgba(0, 0, 0, 0.4);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  transition: background-color 0.3s, color 0.3s;
}

/* =====================
   Header
   ===================== */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent);
}

/* =====================
   Main Navigation
   ===================== */
.main-nav {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  border-radius: 8px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s;
}

.nav-link:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.nav-link.active {
  background-color: var(--accent-light);
  color: var(--accent);
}

.nav-link svg {
  width: 18px;
  height: 18px;
}

/* =====================
   Header Right Side
   ===================== */
.header-right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.header-btn {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: none;
  border-radius: 8px;
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  cursor: pointer;
  transition: background-color 0.2s;
}

.header-btn:hover {
  background-color: var(--border-color);
}

.header-btn svg {
  width: 20px;
  height: 20px;
}

/* Theme toggle icons */
.icon-moon { display: none; }
[data-theme="dark"] .icon-sun { display: none; }
[data-theme="dark"] .icon-moon { display: block; }

/* =====================
   Notifications
   ===================== */
.notification-badge {
  position: absolute;
  top: 4px;
  right: 4px;
  width: 8px;
  height: 8px;
  background-color: var(--danger);
  border-radius: 50%;
}

.notifications-wrapper {
  position: relative;
}

.notifications-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  width: 320px;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.2s;
  z-index: 200;
}

.notifications-wrapper:hover .notifications-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.notifications-header {
  padding: 1rem;
  border-bottom: 1px solid var(--border-color);
  font-weight: 600;
  font-size: 0.875rem;
}

.notifications-list {
  max-height: 300px;
  overflow-y: auto;
}

.notification-item {
  display: flex;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  border-bottom: 1px solid var(--border-color);
  transition: background-color 0.2s;
}

.notification-item:last-child {
  border-bottom: none;
}

.notification-item:hover {
  background-color: var(--bg-tertiary);
}

.notification-item.unread {
  background-color: var(--accent-light);
}

.notification-icon {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.notification-icon.homework {
  background-color: var(--success-light);
  color: var(--success);
}

.notification-icon.reminder {
  background-color: var(--warning-light);
  color: var(--warning);
}

.notification-icon.overdue {
  background-color: var(--danger-light);
  color: var(--danger);
}

.notification-icon svg {
  width: 16px;
  height: 16px;
}

.notification-content {
  flex: 1;
  min-width: 0;
}

.notification-text {
  font-size: 0.8125rem;
  line-height: 1.4;
  color: var(--text-primary);
}

.notification-time {
  font-size: 0.6875rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* =====================
   User Info
   ===================== */
.user-info {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.user-name {
  font-weight: 500;
  color: var(--text-primary);
}

.avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), #8b5cf6);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 0.875rem;
}

/* =====================
   Main Content
   ===================== */
.main {
  padding: 2rem;
  max-width: 1400px;
  margin: 0 auto;
}

.dashboard-grid {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 2rem;
}

.left-column {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

/* =====================
   Cards
   ===================== */
.card {
  background-color: var(--bg-secondary);
  border-radius: 12px;
  border: 1px solid var(--border-color);
  padding: 1.5rem;
  box-shadow: var(--shadow);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.card-title {
  font-size: 1.125rem;
  font-weight: 600;
}

/* =====================
   Calendar
   ===================== */
.calendar-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.badge {
  background-color: var(--accent-light);
  color: var(--accent);
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.875rem;
  font-weight: 500;
}

.week-nav {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.nav-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  background: var(--bg-secondary);
  color: var(--text-primary);
  cursor: pointer;
  transition: all 0.2s;
  text-decoration: none;
}

.nav-btn:hover {
  background: var(--bg-tertiary);
}

.week-label {
  font-weight: 500;
  color: var(--text-secondary);
  min-width: 140px;
  text-align: center;
  font-size: 0.875rem;
}

.btn-add {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background-color: var(--accent);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-add:hover {
  background-color: var(--accent-hover);
  transform: translateY(-1px);
}

.btn-add svg {
  width: 16px;
  height: 16px;
}

.calendar-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 0.75rem;
}

.day-column {
  min-height: 300px;
}

.day-column.drag-over .day-lessons {
  background-color: var(--accent-light);
  border: 2px dashed var(--accent);
  border-radius: 8px;
  min-height: 100px;
}

.day-header {
  text-align: center;
  padding: 0.75rem;
  border-radius: 8px;
  margin-bottom: 0.75rem;
  background-color: var(--bg-tertiary);
}

.day-header.today {
  background-color: var(--accent);
  color: white;
}

.day-name {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}

.day-header.today .day-name {
  color: rgba(255, 255, 255, 0.8);
}

.day-number {
  font-size: 1.25rem;
  font-weight: 600;
  margin-top: 0.25rem;
}

.day-lessons {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  min-height: 50px;
  padding: 0.25rem;
  transition: all 0.2s;
}

/* =====================
   Lesson Cards
   ===================== */
.lesson-card {
  padding: 0.75rem;
  border-radius: 8px;
  border-left: 3px solid;
  background-color: var(--bg-tertiary);
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s, opacity 0.2s;
}

.lesson-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.lesson-card.math { border-left-color: #3b82f6; }
.lesson-card.physics { border-left-color: #8b5cf6; }
.lesson-card.english { border-left-color: #10b981; }
.lesson-card.chemistry { border-left-color: #f59e0b; }

.lesson-time {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: 0.25rem;
}

.lesson-student {
  font-weight: 500;
  font-size: 0.875rem;
}

.lesson-subject {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* Перенесённые занятия */
.lesson-card.rescheduled {
  opacity: 0.6;
  background: repeating-linear-gradient(
    -45deg,
    var(--bg-tertiary),
    var(--bg-tertiary) 4px,
    var(--bg-primary) 4px,
    var(--bg-primary) 8px
  );
}

.lesson-card.rescheduled .lesson-time,
.lesson-card.rescheduled .lesson-student,
.lesson-card.rescheduled .lesson-subject {
  text-decoration: line-through;
  color: var(--text-muted);
}

.lesson-rescheduled-info {
  font-size: 0.6875rem;
  color: var(--warning);
  margin-top: 0.5rem;
  font-weight: 500;
  text-decoration: none !important;
}

/* =====================
   File Manager
   ===================== */
.file-manager-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
  gap: 1rem;
  flex-wrap: wrap;
}

.file-manager-actions {
  display: flex;
  gap: 0.5rem;
}

.storage-info {
  margin-bottom: 1rem;
}

.storage-text {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.storage-bar {
  height: 6px;
  background-color: var(--bg-tertiary);
  border-radius: 3px;
  overflow: hidden;
}

.storage-fill {
  height: 100%;
  background-color: var(--accent);
  border-radius: 3px;
  transition: width 0.3s;
}

.file-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 0.75rem;
}

.file-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 1rem;
  border-radius: 8px;
  background-color: var(--bg-tertiary);
  /* cursor: pointer; */
  transition: all 0.2s;
  text-decoration: none;
  color: var(--text-primary);
}

.file-item:hover {
  /* background-color: var(--border-color);
  transform: translateY(-2px); */
}

.file-info.isImage, .file-info.isVideo {
  cursor: pointer;
}

.file-icon {
  width: 40px;
  height: 40px;
  margin-bottom: 0.5rem;
  color: var(--text-muted);
}

.file-icon.folder { color: var(--warning); }
.file-icon.pdf { color: var(--danger); }
.file-icon.doc { color: var(--accent); }
.file-icon.image { color: var(--success); }

.file-name {
  font-size: 0.75rem;
  font-weight: 500;
  text-align: center;
  word-break: break-word;
  line-height: 1.3;
}

.file-size {
  font-size: 0.625rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* =====================
   Sidebar
   ===================== */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

/* =====================
   Students List
   ===================== */
.students-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  max-height: 280px;
  overflow-y: auto;
}

.student-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem;
  border-radius: 8px;
  cursor: grab;
  transition: background-color 0.2s, transform 0.2s, box-shadow 0.2s;
  user-select: none;
}

.student-item:hover {
  background-color: var(--bg-tertiary);
}

.student-item:active {
  cursor: grabbing;
}

.student-item.ui-draggable-dragging {
  background-color: var(--bg-secondary);
  box-shadow: var(--shadow-lg);
  z-index: 1000;
}

.student-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 0.75rem;
  color: white;
}

.student-info { flex: 1; }

.student-name {
  font-weight: 500;
  font-size: 0.875rem;
}

.student-subject {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.student-lessons {
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-align: right;
}

/* =====================
   Homework List
   ===================== */
.homework-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  /* max-height: 320px; */
  overflow-y: auto;
}

.homework-item {
  padding: 1rem;
  border-radius: 8px;
  background-color: var(--bg-tertiary);
  cursor: pointer;
  transition: background-color 0.2s;
}

.homework-item:hover {
  background-color: var(--border-color);
}

.homework-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 0.5rem;
}

.homework-title {
  font-weight: 500;
  font-size: 0.875rem;
}

.homework-status {
  padding: 0.125rem 0.5rem;
  border-radius: 9999px;
  font-size: 0.625rem;
  font-weight: 500;
  text-transform: uppercase;
}

.status-submitted {
  background-color: var(--success-light);
  color: var(--success);
}

.status-pending {
  background-color: var(--warning-light);
  color: var(--warning);
}

.status-overdue {
  background-color: var(--danger-light);
  color: var(--danger);
}

.homework-student {
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
}

.homework-indicators {
  display: flex;
  gap: 1rem;
}

.indicator {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.75rem;
  color: var(--text-muted);
}

.indicator svg {
  width: 14px;
  height: 14px;
}

.indicator.active {
  color: var(--success);
}

/* =====================
   Modal Windows
   ===================== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.2s;
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal {
  background-color: var(--bg-secondary);
  border-radius: 16px;
  width: 100%;
  max-width: 480px;
  max-height: 90vh;
  overflow-y: auto;
  transform: scale(0.95);
  transition: transform 0.2s;
}

.modal-overlay.active .modal {
  transform: scale(1);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.modal-title {
  font-size: 1.125rem;
  font-weight: 600;
}

.modal-close {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: none;
  border-radius: 8px;
  background-color: transparent;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s;
}

.modal-close:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.modal-body {
  padding: 1.5rem;
}

/* =====================
   Forms
   ===================== */
.form-group {
  margin-bottom: 1.25rem;
}

.form-group:last-child {
  margin-bottom: 0;
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 0.875rem;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  font-family: inherit;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.radio-group {
  display: flex;
  gap: 1rem;
}

.radio-label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  font-size: 0.875rem;
}

.radio-label input[type="radio"] {
  appearance: none;
  width: 18px;
  height: 18px;
  border: 2px solid var(--border-color);
  border-radius: 50%;
  cursor: pointer;
  transition: all 0.2s;
}

.radio-label input[type="radio"]:checked {
  border-color: var(--accent);
  background: radial-gradient(circle, var(--accent) 40%, transparent 40%);
}

/* Checkbox styling */
.checkbox-label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  font-size: 0.875rem;
  padding: 0.75rem;
  background-color: var(--bg-tertiary);
  border-radius: 8px;
  border: 1px solid var(--border-color);
  transition: all 0.2s;
}

.checkbox-label:hover {
  background-color: var(--border-color);
}

.checkbox-label input[type="checkbox"] {
  appearance: none;
  width: 18px;
  height: 18px;
  border: 2px solid var(--border-color);
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s;
  flex-shrink: 0;
  background-color: #64748b;
}

.checkbox-label input[type="checkbox"]:checked {
  /* border-color: var(--accent); */
  background-color: var(--accent);
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 16 16' fill='white' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M12.207 4.793a1 1 0 010 1.414l-5 5a1 1 0 01-1.414 0l-2-2a1 1 0 011.414-1.414L6.5 9.086l4.293-4.293a1 1 0 011.414 0z'/%3E%3C/svg%3E");
}

.checkbox-description {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.125rem;
}

/* =====================
   Dropzone
   ===================== */
.dropzone {
  border: 2px dashed var(--border-color);
  border-radius: 12px;
  padding: 2rem;
  text-align: center;
  cursor: pointer;
  transition: all 0.2s;
}

.dropzone:hover,
.dropzone.drag-over {
  border-color: var(--accent);
  background-color: var(--accent-light);
}

.dropzone-icon {
  width: 48px;
  height: 48px;
  color: var(--text-muted);
  margin: 0 auto 1rem;
}

.dropzone-text {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.dropzone-hint {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* =====================
   Modal Footer & Buttons
   ===================== */
.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border-color);
}

.btn {
  padding: 0.625rem 1.25rem;
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-secondary {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background-color: var(--border-color);
}

.btn-primary {
  background-color: var(--accent);
  color: white;
  border: none;
}

.btn-primary:hover {
  background-color: var(--accent-hover);
}

.btn-danger {
  background-color: var(--danger);
  color: white;
  border: none;
}

.btn-danger:hover {
  background-color: #dc2626;
}

/* =====================
   Login Page
   ===================== */
.login-container {
  width: 100%;
  max-width: 420px;
}

.login-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.login-card {
  background: var(--bg-card);
  border-radius: 16px;
  box-shadow: var(--shadow-lg);
  padding: 40px;
  border: 1px solid var(--border-color);
}

.login-header {
  text-align: center;
  margin-bottom: 32px;
}

.login-logo {
  width: 64px;
  height: 64px;
  background: linear-gradient(135deg, var(--accent), #8b5cf6);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
}

.login-logo svg {
  width: 32px;
  height: 32px;
  color: white;
}

.login-header h1 {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 8px;
}

.login-header p {
  font-size: 14px;
  color: var(--text-secondary);
}

.input-wrapper {
  position: relative;
}

.input-wrapper svg {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  width: 20px;
  height: 20px;
  color: var(--text-secondary);
}

.input-wrapper .form-input {
  padding-left: 46px;
}

.password-toggle {
  position: absolute;
  right: 14px;
  top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-secondary);
  padding: 4px;
  display: flex;
}

.password-toggle:hover {
  color: var(--text-primary);
}

.password-toggle svg {
  position: static;
  transform: none;
}

.form-options {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
  font-size: 14px;
}

.remember-me {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
}

.remember-me input {
  width: 18px;
  height: 18px;
  accent-color: var(--accent);
}

.remember-me span {
  color: var(--text-secondary);
}

.forgot-link {
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
}

.forgot-link:hover {
  text-decoration: underline;
}

.login-btn {
  width: 100%;
  padding: 14px;
  font-size: 16px;
  font-weight: 600;
  color: white;
  background: linear-gradient(135deg, var(--accent), #2563eb);
  border: none;
  border-radius: 10px;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
}

.login-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.login-footer {
  text-align: center;
  margin-top: 24px;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
}

.login-footer p {
  font-size: 14px;
  color: var(--text-secondary);
}

.login-footer a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
}

.login-footer a:hover {
  text-decoration: underline;
}

.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow);
  transition: background 0.3s;
}

.theme-toggle:hover {
  background: var(--bg-secondary);
}

.theme-toggle svg {
  width: 22px;
  height: 22px;
  color: var(--text-primary);
}

.theme-toggle .icon-moon,
[data-theme="dark"] .theme-toggle .icon-sun {
  display: none;
}

[data-theme="dark"] .theme-toggle .icon-moon {
  display: block;
}

.error-message {
  background: var(--danger-light);
  border: 1px solid var(--danger);
  color: var(--danger);
  padding: 12px 16px;
  border-radius: 10px;
  font-size: 14px;
  margin-bottom: 20px;
}
[data-theme="dark"] .error-message {
    background: rgba(220, 38, 38, 0.1);
    border-color: rgba(220, 38, 38, 0.3);
}

/* =====================
   PIN Login Page
   ===================== */
.pin-card {
  max-width: 360px;
}

.student-logo {
  background: linear-gradient(135deg, #10b981, #059669);
}

.pin-display {
  margin-bottom: 24px;
}

.pin-dots {
  display: flex;
  justify-content: center;
  gap: 16px;
}

.pin-dot {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background-color: var(--bg-tertiary);
  border: 2px solid var(--border-color);
  transition: all 0.2s ease;
}

.pin-dot.filled {
  background-color: var(--accent);
  border-color: var(--accent);
  transform: scale(1.1);
}

.pin-dot.pop {
  animation: pinPop 0.2s ease;
}

@keyframes pinPop {
  0% { transform: scale(1); }
  50% { transform: scale(1.3); }
  100% { transform: scale(1.1); }
}

.pin-keypad {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 24px;
}

.pin-key {
  height: 64px;
  border: 1px solid var(--border-color);
  border-radius: 12px;
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  font-size: 24px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.pin-key:hover:not(:disabled) {
  background-color: var(--bg-tertiary);
  border-color: var(--accent);
}

.pin-key:active:not(:disabled),
.pin-key.pressed {
  background-color: var(--accent);
  border-color: var(--accent);
  color: white;
  transform: scale(0.95);
}

.pin-key-empty {
  background: transparent;
  border: none;
  cursor: default;
}

.pin-key-backspace {
  background-color: var(--bg-tertiary);
}

.pin-key-backspace svg {
  width: 24px;
  height: 24px;
}

.pin-key-backspace:hover {
  background-color: var(--danger-light);
  border-color: var(--danger);
  color: var(--danger);
}

.pin-submit {
  margin-top: 8px;
}

.pin-submit:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.pin-submit:disabled:hover {
  transform: none;
  box-shadow: none;
}

/* =====================
   Student Page
   ===================== */
.next-lesson {
  background: linear-gradient(135deg, var(--accent), #6366f1);
  border-radius: 16px;
  padding: 1.5rem 2rem;
  color: white;
  margin-bottom: 2rem;
  box-shadow: var(--shadow-lg);
}

.next-lesson-label {
  font-size: 0.875rem;
  opacity: 0.9;
  margin-bottom: 0.5rem;
}

.next-lesson-date {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.next-lesson-time {
  font-size: 1.125rem;
  opacity: 0.9;
}

.next-lesson-subject {
  display: inline-block;
  margin-top: 1rem;
  padding: 0.375rem 0.875rem;
  background: rgba(255,255,255,0.2);
  border-radius: 20px;
  font-size: 0.875rem;
  font-weight: 500;
}

.audio-playback-container {
  margin-top: 1rem;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.audio-playback {
  width: 100%;
  height: 36px;
}

.audio-playback::-webkit-media-controls-panel {
  background-color: var(--bg-tertiary);
}

.audio-playback::-webkit-media-controls-mute-button,
.audio-playback::-webkit-media-controls-play-button {
  background-color: transparent;
  border: none;
}

.audio-record {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 20px;
}

.recordButton,
.stopButton {
  display: inline-flex !important;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1rem;
  border-radius: 8px;
  font-size: 0.9375rem;
  font-weight: 500;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
}

.recordButton {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.recordButton:hover:not(:disabled) {
  background-color: var(--accent-light);
  border-color: var(--accent);
  color: var(--accent);
}

.recordButton:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.stopButton {
  background-color: var(--danger-light);
  color: var(--danger);
  border: 1px solid var(--danger);
}

.stopButton:hover:not(:disabled) {
  background-color: var(--danger);
  color: white;
}

.stopButton:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.recordButton svg,
.stopButton svg {
  width: 16px;
  height: 16px;
}

.section-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.hidden {
  display: none;
}

/* =====================
   Chat Widget
   ===================== */
.chat-widget {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  margin-bottom: 1.5rem;
  overflow: hidden;
}

.chat-widget-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  background-color: var(--bg-secondary);
  cursor: pointer;
  transition: background-color 0.2s;
  user-select: none;
}

.chat-widget-header:hover {
  background-color: var(--bg-tertiary);
}

.chat-widget-title {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 600;
  color: var(--text-primary);
}

.chat-widget-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 20px;
  height: 20px;
  transition: transform 0.2s;
}

.chat-widget-content {
  display: flex;
  flex-direction: column;
  max-height: 400px;
  border-top: 1px solid var(--border-color);
}

.chat-widget-messages {
  flex: 1;
  overflow-y: auto;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.chat-widget-message {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 0.75rem 1rem;
  border-radius: 8px;
  background-color: var(--bg-tertiary);
  font-size: 0.9375rem;
}

.chat-widget-message strong {
  font-size: 0.8125rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.chat-widget-message p {
  margin: 0;
  color: var(--text-primary);
  line-height: 1.4;
}

.chat-widget-message.own {
  align-self: flex-end;
  max-width: 80%;
  background-color: var(--accent-light);
  color: var(--accent);
}

.chat-widget-message.own strong {
  color: var(--accent);
}

.chat-widget-message.other {
  align-self: flex-start;
  max-width: 80%;
}

.chat-widget-form {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem;
  background-color: var(--bg-tertiary);
  border-top: 1px solid var(--border-color);
}

.chat-widget-input {
  flex: 1;
  border: 1px solid var(--border-color);
  background-color: var(--bg-secondary);
  border-radius: 6px;
  padding: 0.625rem 0.75rem;
  color: var(--text-primary);
  font-size: 0.875rem;
  outline: none;
}

.chat-widget-input:focus {
  border-color: var(--accent);
}

.chat-widget-input::placeholder {
  color: var(--text-muted);
}

.chat-widget-send {
  width: 32px;
  height: 32px;
  border: none;
  background-color: var(--accent);
  border-radius: 6px;
  color: white;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.2s;
  flex-shrink: 0;
}

.chat-widget-send:hover {
  background-color: var(--accent-hover);
}

/* Student homework items */
.homework-item-student {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: var(--shadow);
  margin-bottom: 1rem;
}

.homework-item-student .homework-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  cursor: pointer;
  transition: background-color 0.2s;
  margin-bottom: 0;
}

.homework-item-student .homework-header:hover {
  background-color: var(--bg-tertiary);
}

.homework-status-icon {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.homework-status-icon.submitted {
  background-color: var(--success-light);
  color: var(--success);
}

.homework-status-icon.pending {
  background-color: var(--warning-light);
  color: var(--warning);
}

.homework-status-icon.overdue {
  background-color: var(--danger-light);
  color: var(--danger);
}

.homework-status-icon svg {
  width: 18px;
  height: 18px;
}

.homework-toggle {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  transition: transform 0.3s;
}

.homework-toggle svg {
  width: 20px;
  height: 20px;
}

.homework-item-student.expanded .homework-toggle {
  transform: rotate(180deg);
}

.homework-content {
  display: none;
  padding: 0 1.25rem 1.25rem;
  border-top: 1px solid var(--border-color);
}

.homework-item-student.expanded .homework-content {
  display: block;
}

.homework-description {
  padding-top: 1.25rem;
  font-size: 0.9375rem;
  line-height: 1.7;
  margin-bottom: 1.25rem;
}

.homework-description ul, .homework-description ol {
  margin-left: 15px
}

/* Upload zone for student */
.upload-zone {
  border: 2px dashed var(--border-color);
  border-radius: 8px;
  padding: 1.5rem;
  text-align: center;
  transition: all 0.2s;
  cursor: pointer;
  margin-bottom: 1rem;
  background-color: var(--bg-secondary);
}

.upload-zone:hover,
.upload-zone.dragover {
  border-color: var(--accent);
  background-color: var(--accent-light);
}

.upload-zone-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 0.75rem;
  color: var(--text-muted);
}

.upload-zone-icon svg {
  width: 100%;
  height: 100%;
}

.upload-zone-text {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 0.25rem;
}

.upload-zone-hint {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.upload-zone-link {
  color: var(--accent);
  cursor: pointer;
  font-weight: 500;
}

.submit-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.875rem;
  background-color: var(--accent);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 0.9375rem;
  font-weight: 600;
  cursor: pointer;
  transition: background-color 0.2s;
}

.submit-btn:hover {
  background-color: var(--accent-hover);
}

.submit-btn svg {
  width: 18px;
  height: 18px;
}

/* =====================
   Students Page
   ===================== */
.page-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.page-title {
  font-size: 1.75rem;
  font-weight: 700;
}

.students-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
}

.student-card {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 1.5rem;
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: var(--shadow);
}

.student-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--accent);
}

.student-card-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.student-avatar-lg {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.125rem;
  color: white;
  flex-shrink: 0;
}

.student-card-info {
  flex: 1;
  min-width: 0;
}

.student-card-name {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.student-card-subject {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.student-card-details {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  padding: 1rem 0;
  border-top: 1px solid var(--border-color);
  margin-bottom: 1rem;
}

.detail-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8125rem;
}

.detail-label {
  color: var(--text-muted);
}

.detail-value {
  color: var(--text-primary);
  font-weight: 500;
}

.student-card-stats {
  display: flex;
  gap: 2rem;
}

.stat {
  display: flex;
  flex-direction: column;
}

.stat-value {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent);
}

.stat-label {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* Custom fields divider */
.custom-fields-divider {
  display: flex;
  align-items: center;
  margin: 1.5rem 0 1rem;
  color: var(--text-muted);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.custom-fields-divider::before,
.custom-fields-divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background-color: var(--border-color);
}

.custom-fields-divider::before {
  margin-right: 1rem;
}

.custom-fields-divider::after {
  margin-left: 1rem;
}

.fm-ctx{
  position: fixed;
  z-index: 9999;
  min-width: 180px;
  background: var(--bg-primary, #fff);
  border: 1px solid var(--border-color, rgba(0,0,0,.12));
  border-radius: 10px;
  box-shadow: 0 12px 30px rgba(0,0,0,.18);
  padding: 6px;
  user-select: none;
}
.fm-ctx-item{
  padding: 10px 10px;
  border-radius: 8px;
  cursor: pointer;
  color: var(--text-primary, #111);
  font-size: 14px;
  line-height: 1;
}
.fm-ctx-item:hover{
  background: var(--bg-tertiary, rgba(0,0,0,.06));
}
.fm-ctx-sep{
  height: 1px;
  margin: 6px 4px;
  background: var(--border-color, rgba(0,0,0,.12));
}

.preview-container { display: none; }

/* =====================
   Homework Page
   ===================== */
.main-content {
  padding: 2rem;
  max-width: 1400px;
  margin: 0 auto;
}

.container {
  width: 100%;
}

/* Filters Bar */
.filters-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.filter-tabs {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.filter-tab {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s;
}

.filter-tab:hover {
  border-color: var(--accent);
  color: var(--text-primary);
}

.filter-tab.active {
  background-color: var(--accent);
  border-color: var(--accent);
  color: white;
}

.filter-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 20px;
  height: 20px;
  padding: 0 6px;
  background-color: var(--bg-tertiary);
  border-radius: 10px;
  font-size: 0.75rem;
  font-weight: 600;
}

.filter-tab.active .filter-count {
  background-color: rgba(255, 255, 255, 0.2);
}

.filter-count.success {
  background-color: var(--success-light);
  color: var(--success);
}

.filter-count.danger {
  background-color: var(--danger-light);
  color: var(--danger);
}

.filter-search {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  min-width: 250px;
}

.filter-search.select-filter {
  padding: 0;
  overflow: hidden;
}

#studentFilter {
  flex: 1;
  border: none;
  background: transparent;
  font-size: 0.875rem;
  color: var(--text-primary);
  outline: none;
  padding: 0.5rem 1rem;
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml;charset=UTF-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23666' stroke-width='2'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  background-size: 18px;
  padding-right: 2.5rem;
}

[data-theme="dark"] #studentFilter {
  background-image: url("data:image/svg+xml;charset=UTF-8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23999' stroke-width='2'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
}

#studentFilter:hover {
  background-color: var(--bg-tertiary);
}

#studentFilter option {
  background-color: var(--bg-secondary);
  color: var(--text-primary);
}

.filter-search svg {
  color: var(--text-muted);
  flex-shrink: 0;
}

.search-input {
  flex: 1;
  border: none;
  background: transparent;
  font-size: 0.875rem;
  color: var(--text-primary);
  outline: none;
}

.search-input::placeholder {
  color: var(--text-muted);
}

/* Homework Table */
.homework-table {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  overflow: hidden;
}

.homework-table-header {
  display: grid;
  grid-template-columns: 60px 1fr 180px 120px 80px 80px;
  gap: 1rem;
  padding: 0.875rem 1.25rem;
  background-color: var(--bg-tertiary);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.homework-row {
  display: grid;
  grid-template-columns: 60px 1fr 180px 120px 80px 80px;
  gap: 1rem;
  padding: 1rem 1.25rem;
  align-items: center;
  border-bottom: 1px solid var(--border-color);
  cursor: pointer;
  transition: background-color 0.2s;
}

.homework-row:last-child {
  border-bottom: none;
}

.homework-row:hover {
  background-color: var(--bg-tertiary);
}

.homework-row.overdue {
  background-color: var(--danger-light);
}

.homework-row.overdue:hover {
  background-color: rgba(239, 68, 68, 0.15);
}

.hw-col-status {
  display: flex;
  justify-content: center;
}

.hw-status-badge {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
}

.hw-status-badge.success {
  background-color: var(--success-light);
  color: var(--success);
}

.hw-status-badge.warning {
  background-color: var(--warning-light);
  color: var(--warning);
}

.hw-status-badge.danger {
  background-color: var(--danger-light);
  color: var(--danger);
}

.hw-col-title {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.hw-title {
  font-weight: 500;
  color: var(--text-primary);
}

.hw-files-count {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.75rem;
  color: var(--text-muted);
}

.hw-col-student {
  display: flex;
  align-items: center;
}

.hw-student {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
}

.hw-student-avatar {
  width: 24px;
  height: 24px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.625rem;
  font-weight: 600;
  color: white;
  flex-shrink: 0;
}

.hw-col-date {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.overdue-date {
  display: block;
  color: var(--danger);
}

.overdue-label {
  display: block;
  font-size: 0.6875rem;
  color: var(--danger);
  font-weight: 500;
}

.hw-col-downloaded,
.hw-col-submitted {
  display: flex;
  justify-content: center;
}

.hw-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 6px;
}

.hw-icon.success {
  background-color: var(--success-light);
  color: var(--success);
}

.hw-icon.muted {
  background-color: var(--bg-tertiary);
  color: var(--text-muted);
}

/* Pagination */
.pagination {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
}

.pagination-info {
  font-size: 0.875rem;
  color: var(--text-muted);
}

.pagination-controls {
  display: flex;
  align-items: center;
  gap: 0.375rem;
}

.pagination-btn,
.pagination-num {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  height: 36px;
  padding: 0 0.5rem;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s;
}

.pagination-btn:hover:not(.disabled),
.pagination-num:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.pagination-btn.disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

.pagination-num.active {
  background-color: var(--accent);
  border-color: var(--accent);
  color: white;
}

.pagination-dots {
  padding: 0 0.5rem;
  color: var(--text-muted);
}

/* Modal Large */
.modal-lg {
  max-width: 600px;
}

/* File Selector */
.file-selector {
  border: 1px solid var(--border-color);
  border-radius: 8px;
  overflow: hidden;
}

.file-selector-header {
  padding: 0.75rem 1rem;
  background-color: var(--bg-tertiary);
  border-bottom: 1px solid var(--border-color);
}

.file-selector-path {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.8125rem;
}

.path-item {
  color: var(--text-muted);
  cursor: pointer;
  transition: color 0.2s;
}

.path-item:hover {
  color: var(--accent);
}

.path-item.active {
  color: var(--text-primary);
  font-weight: 500;
}

.path-separator {
  color: var(--text-muted);
}

.file-selector-list {
  max-height: 250px;
  overflow-y: auto;
}

.file-selector-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.625rem 1rem;
  cursor: pointer;
  transition: background-color 0.15s;
  border-bottom: 1px solid var(--border-color);
}

.file-selector-item:last-child {
  border-bottom: none;
}

.file-selector-item:hover {
  background-color: var(--bg-tertiary);
}

.file-selector-item.file {
  cursor: pointer;
}

.file-checkbox {
  width: 16px;
  height: 16px;
  accent-color: var(--accent);
  cursor: pointer;
}

.file-selector-icon {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  flex-shrink: 0;
}

.file-selector-icon.folder {
  background-color: var(--warning-light);
  color: var(--warning);
}

.file-selector-icon.pdf {
  background-color: var(--danger-light);
  color: var(--danger);
}

.file-selector-icon.doc {
  background-color: var(--accent-light);
  color: var(--accent);
}

.file-selector-icon.image {
  background-color: var(--success-light);
  color: var(--success);
}

.file-selector-name {
  flex: 1;
  font-size: 0.875rem;
  min-width: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.file-selector-size {
  font-size: 0.75rem;
  color: var(--text-muted);
  flex-shrink: 0;
}

.file-selector-footer {
  padding: 0.75rem 1rem;
  background-color: var(--bg-tertiary);
  border-top: 1px solid var(--border-color);
  font-size: 0.8125rem;
  color: var(--text-secondary);
}

.files-selected strong {
  color: var(--accent);
}

.form-hint {
  font-weight: 400;
  color: var(--text-muted);
}

.form-help {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.375rem;
}

.audio-item {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}
.audio-toggle {
  background-color: var(--accent-light);
  width: 34px;
  height: 34px;
  border-radius: 10px;
  border: 0px;
  /* background: var(--bg-tertiary); */
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  line-height: 1;
  color: currentColor;
}

/* =====================
   Upcoming Lesson Alert
   ===================== */
.upcoming-lesson-alert {
  animation: slideDown 0.3s ease;
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.upcoming-lesson-alert .btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: all 0.2s;
}

.upcoming-lesson-alert .btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.upcoming-lesson-alert .btn-secondary {
  background-color: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: var(--text-primary);
}

.upcoming-lesson-alert .btn-secondary:hover {
  background-color: rgba(255, 255, 255, 0.15);
  border-color: rgba(59, 130, 246, 0.5);
}

/* =====================
   Mobile Menu
   ===================== */
.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: none;
  border-radius: 8px;
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  cursor: pointer;
  transition: background-color 0.2s;
}

.menu-toggle:hover {
  background-color: var(--border-color);
}

.menu-toggle svg {
  width: 20px;
  height: 20px;
}

.mobile-menu-overlay {
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: 150;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s;
}

.mobile-menu-overlay.active {
  opacity: 1;
  visibility: visible;
}

.mobile-menu {
  position: fixed;
  top: 0;
  left: 0;
  width: 280px;
  height: 100vh;
  background-color: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  z-index: 151;
  transform: translateX(-100%);
  transition: transform 0.3s ease;
  display: flex;
  flex-direction: column;
}

.mobile-menu-overlay.active .mobile-menu {
  transform: translateX(0);
}

.mobile-menu-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-color);
}

.mobile-menu-logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent);
}

.mobile-menu-close {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: none;
  border-radius: 8px;
  background-color: transparent;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s;
}

.mobile-menu-close:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.mobile-menu-close svg {
  width: 20px;
  height: 20px;
}

.mobile-menu-nav {
  flex: 1;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  border-radius: 8px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s;
}

.mobile-nav-link:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.mobile-nav-link.active {
  background-color: var(--accent-light);
  color: var(--accent);
}

.mobile-nav-link svg {
  width: 20px;
  height: 20px;
}

.mobile-menu-footer {
  padding: 1rem 1.25rem;
  border-top: 1px solid var(--border-color);
}

.mobile-user-info {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.mobile-user-name {
  font-weight: 500;
  font-size: 0.9375rem;
}

/* =====================
   Mobile Menu
   ===================== */
.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: none;
  border-radius: 8px;
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  cursor: pointer;
  transition: background-color 0.2s;
}

.menu-toggle:hover {
  background-color: var(--border-color);
}

.menu-toggle svg {
  width: 20px;
  height: 20px;
}

.mobile-menu-overlay {
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: 150;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s;
}

.mobile-menu-overlay.active {
  opacity: 1;
  visibility: visible;
}

.mobile-menu {
  position: fixed;
  top: 0;
  left: 0;
  width: 280px;
  height: 100vh;
  background-color: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  z-index: 151;
  transform: translateX(-100%);
  transition: transform 0.3s ease;
  display: flex;
  flex-direction: column;
}

.mobile-menu-overlay.active .mobile-menu {
  transform: translateX(0);
}

.mobile-menu-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-color);
}

.mobile-menu-logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent);
}

.mobile-menu-close {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: none;
  border-radius: 8px;
  background-color: transparent;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s;
}

.mobile-menu-close:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.mobile-menu-close svg {
  width: 20px;
  height: 20px;
}

.mobile-menu-nav {
  flex: 1;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  overflow-y: auto;
}

.mobile-nav-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  border-radius: 8px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: all 0.2s;
}

.mobile-nav-link:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.mobile-nav-link.active {
  background-color: var(--accent-light);
  color: var(--accent);
}

.mobile-nav-link svg {
  width: 20px;
  height: 20px;
}

.mobile-menu-footer {
  padding: 1rem 1.25rem;
  border-top: 1px solid var(--border-color);
}

.mobile-user-info {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.mobile-user-name {
  font-weight: 500;
  font-size: 0.9375rem;
}

/* =====================
   Notifications
   ===================== */
.notifications-wrapper {
  position: relative;
}

.notification-badge {
  position: absolute;
  top: -4px;
  right: -4px;
  width: 12px;
  height: 12px;
  background-color: var(--danger);
  border-radius: 50%;
  border: 2px solid var(--bg-secondary);
}

.notifications-dropdown {
  position: absolute;
  top: 100%;
  right: 0;
  width: 320px;
  max-height: 400px;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  box-shadow: var(--shadow-lg);
  z-index: 200;
  opacity: 0;
  visibility: hidden;
  transition: all 0.2s;
  pointer-events: none;
  margin-top: 0.5rem;
}

.notifications-dropdown.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.notifications-header {
  padding: 0.875rem 1rem;
  font-weight: 600;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.875rem;
}

.notifications-list {
  max-height: 350px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
}

.notification-item {
  display: flex;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  border-bottom: 1px solid var(--border-color);
  cursor: pointer;
  transition: background-color 0.2s;
}

.notification-item:hover {
  background-color: var(--bg-tertiary);
}

.notification-item.unread {
  background-color: var(--accent-light);
}

.notification-icon {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.notification-icon.homework {
  background-color: var(--success-light);
  color: var(--success);
}

.notification-icon.reminder {
  background-color: var(--warning-light);
  color: var(--warning);
}

.notification-icon.overdue {
  background-color: var(--danger-light);
  color: var(--danger);
}

.notification-icon svg {
  width: 16px;
  height: 16px;
}

.notification-content {
  flex: 1;
  min-width: 0;
}

.notification-text {
  font-size: 0.8125rem;
  line-height: 1.4;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.notification-time {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* =====================
   Chats Page
   ===================== */
.chats-container {
  display: flex;
  height: calc(100vh - 73px);
  background-color: var(--bg-primary);
}

.chats-sidebar {
  width: 320px;
  background-color: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
}

.chats-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-color);
}

.chats-header h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0;
}

.chats-search-toggle {
  width: 32px;
  height: 32px;
  border: none;
  background-color: var(--bg-tertiary);
  border-radius: 8px;
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
}

.chats-search-toggle:hover {
  background-color: var(--border-color);
  color: var(--text-primary);
}

.chats-search {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border-color);
}

.chats-search input {
  width: 100%;
  padding: 0.625rem 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  font-size: 0.875rem;
  outline: none;
}

.chats-search input:focus {
  border-color: var(--accent);
  background-color: var(--bg-secondary);
}

.chats-search input::placeholder {
  color: var(--text-muted);
}

.chats-list {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.chat-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  border-bottom: 1px solid var(--border-color);
  cursor: pointer;
  transition: all 0.2s;
  position: relative;
}

.chat-item:hover {
  background-color: var(--bg-tertiary);
}

.chat-item.active {
  background-color: var(--accent-light);
  border-left: 3px solid var(--accent);
  padding-left: calc(1rem - 3px);
}

.chat-avatar {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  color: white;
  background: linear-gradient(135deg, #f97316, #ea580c);
  flex-shrink: 0;
}

.chat-info {
  flex: 1;
  min-width: 0;
}

.chat-name {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.chat-preview {
  font-size: 0.8125rem;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.chat-time {
  font-size: 0.75rem;
  color: var(--text-muted);
  flex-shrink: 0;
}

.chat-unread {
  position: absolute;
  top: 0.5rem;
  right: 1rem;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background-color: var(--accent);
  color: white;
  font-size: 0.7rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Chat content */
.chat-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  background-color: var(--bg-primary);
}

.chat-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
}

.chat-header-info {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.chat-avatar-lg {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  color: white;
  background: linear-gradient(135deg, #f97316, #ea580c);
}

.chat-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin: 0 0 0.25rem 0;
}

.chat-status {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.chat-header-actions {
  display: flex;
  gap: 0.5rem;
}

.chat-action-btn {
  width: 36px;
  height: 36px;
  border: none;
  border-radius: 8px;
  background-color: var(--bg-tertiary);
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
}

.chat-action-btn:hover {
  background-color: var(--accent-light);
  color: var(--accent);
}

/* Messages */
.messages-container {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.message-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.message-time {
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
}

.message {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
}

.message.own {
  justify-content: flex-end;
}

.message-avatar {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  color: white;
  background: linear-gradient(135deg, #f97316, #ea580c);
  flex-shrink: 0;
  font-size: 0.8125rem;
}

.message-content {
  max-width: 60%;
}

.message.own .message-content {
  max-width: 100%;
}

.message-text {
  padding: 0.75rem 1rem;
  border-radius: 12px;
  font-size: 0.9375rem;
  color: var(--text-primary);
  background-color: var(--bg-secondary);
  word-wrap: break-word;
  line-height: 1.4;
}

.message.own .message-text {
  background-color: var(--accent);
  color: white;
  border-radius: 12px 4px 12px 12px;
}

.message.other .message-text {
  background-color: var(--bg-tertiary);
  border-radius: 4px 12px 12px 12px;
}

.message-status {
  display: flex;
  gap: 2px;
  margin-top: 4px;
  justify-content: flex-end;
}

.status-check {
  color: var(--text-muted);
  stroke-linecap: round;
  stroke-linejoin: round;
}

.status-check.read {
  color: var(--accent);
}

/* Message input */
.message-input-container {
  padding: 1rem 1.5rem;
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
}

.message-input-form {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  background-color: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: 24px;
  padding: 0.5rem 0.75rem;
  transition: all 0.2s;
}

.message-input-form:focus-within {
  border-color: var(--accent);
  background-color: var(--bg-secondary);
}

.message-input-btn svg, .message-input-btn, .chat-widget-form svg {
  width: 32px;
  height: 32px;
  border: none;
  background: none;
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.2s;
  flex-shrink: 0;
}

.message-input-btn:hover, .message-input-btn:hover svg, .chat-widget-form svg:hover {
  color: var(--accent);
}

.message-input {
  flex: 1;
  border: none;
  background: transparent;
  color: var(--text-primary);
  font-size: 0.9375rem;
  outline: none;
  resize: none;
  max-height: 100px;
}

.message-input::placeholder {
  color: var(--text-muted);
}

.message-send-btn {
  width: 32px;
  height: 32px;
  border: none;
  background: none;
  color: var(--accent);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.2s;
  flex-shrink: 0;
}

.message-send-btn:hover {
  transform: scale(1.1);
}

.chats-sidebar-toggle {
    display: none;
}
/* =====================
   Responsive Design
   ===================== */
@media (max-width: 1024px) {
  .chats-container {
    position: relative;
  }

  /* .dashboard-grid {
    display: flex;
    gap: 2rem;
    flex-direction: column;
  } */


  .chats-sidebar {
    position: fixed;
    left: 0;
    top: 73px;
    width: 320px;
    height: calc(100vh - 73px);
    z-index: 100;
    transform: translateX(-100%);
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  }

  .chats-sidebar.active {
    transform: translateX(0);
  }

  .chats-sidebar-overlay {
    position: fixed;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 99;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
    top: 73px;
    height: calc(100vh - 73px);
  }

  .chats-sidebar-overlay.active {
    opacity: 1;
    visibility: visible;
  }

  .chats-sidebar-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border: none;
    background-color: var(--bg-tertiary);
    border-radius: 8px;
    color: var(--text-secondary);
    cursor: pointer;
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    margin-left: 0.75rem;
    transition: all 0.2s;
  }

  .chats-sidebar-toggle:hover {
    background-color: var(--border-color);
    color: var(--text-primary);
  }

  .chat-content {
    flex: 1;
  }

  /* .chat-header {
    padding-left: 56px;
  } */
}

@media (max-width: 768px) {
  .chats-container {
    flex-direction: column;
  }

  .chats-sidebar {
    width: 280px;
  }

  .chat-header-info {
    /* flex-direction: column; */
    gap: 0.75rem;
  }

  .chat-header-actions {
    flex-wrap: wrap;
    gap: 0.5rem;
  }

  .message-content {
    max-width: 85% !important;
  }

  .messages-container {
    padding: 1rem;
  }

  .message-input-form {
    flex-wrap: wrap;
  }
}

@media (max-width: 1024px) {
  .main-nav {
    display: none;
  }
  .menu-toggle {
    display: flex;
  }
  .header-left {
    gap: 1rem;
  }
}

@media (max-width: 768px) {
  .header {
    padding: 0.75rem 1rem;
  }
  .user-name {
    display: none;
  }
  .header-right {
    gap: 0.5rem;
  }
}











/* Модальный (фон) */
.modal-image {
  display: none; /* Скрыто по умолчанию */
  position: fixed; /* Оставаться на месте */
  z-index: 100; /* Сидеть на вершине */
  padding: 5vh 0px; /* Расположение коробки */
  left: 0;
  top: 0;
  width: 100%; /* Полная ширина */
  height: 100%; /* Полный высота */
  overflow: auto; /* Включите прокрутку, если это необходимо */
  background-color: rgb(0,0,0); /* Цвет запасной вариант */
  background-color: rgba(0,0,0,0.9); /* Черный с непрозрачностью */
  box-sizing: border-box;
}

/* Модальное содержание (изображение) */
.modal-image .modal-content {
  margin: auto;
  display: block;
  max-height: 90vh;
}
  .modal-image .modal-content img, .modal-image .modal-content video {
    display: block;
    height: 90vh;
    margin: auto;
  }

/* Добавить анимацию - величение модели */
.modal-image .modal-content {
  animation-name: zoom;
  animation-duration: 0.6s;
}

@keyframes zoom {
  from {transform:scale(0)}
  to {transform:scale(1)}
}

/* Кнопка закрытия */
.modal-image .close {
  position: absolute;
  top: 15px;
  right: 35px;
  color: #f1f1f1;
  font-size: 40px;
  font-weight: bold;
  transition: 0.3s;
}

.modal-image .close:hover,
.modal-image .close:focus {
  color: #bbb;
  text-decoration: none;
  cursor: pointer;
}

.lessonDelimiter {
  height: 40px;
  justify-content: center;
  align-items: center;
  font-size: 10px;
  pointer-events: none;
  color: var(--text-secondary);
  text-align: center;
  position: relative;
}

/* 100% Ширина изображения на меньших экранах */
@media only screen and (max-width: 700px){
  .modal-image .modal-content {
    width: 100%;
  }
}