:root {
  --primary-green: #2e8b57;
  --light-green: #9ccc65;
  --dark-green: #1b5e20;
  --mint-green: #e8f5e9;
  --teal: #00897b;
  --light-teal: #b2dfdb;
  --white: #ffffff;
  --light-gray: #f5f7fa;
  --medium-gray: #e0e0e0;
  --dark-gray: #455a64;
  --error-red: #e53935;
  --warning-orange: #fb8c00;
  --text-dark: #263238;
  --text-light: #eceff1;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.12);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.16);
  --shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.1);

  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  scrollbar-width: none;
}

body {
  font-family:
    "Poppins",
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Roboto,
    Oxygen,
    Ubuntu,
    Cantarell,
    sans-serif;
  line-height: 1.6;
  color: var(--text-dark);
  background-color: var(--light-gray);
  -webkit-font-smoothing: antialiased;
}

/* ───────────────────────────────
   ✳️ Layout Components
──────────────────────────────── */
.app-container {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.app-main {
  flex: 1;
  padding: 2.5rem 1.5rem;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

.app-header {
  background: linear-gradient(135deg, var(--primary-green), var(--teal));
  color: var(--white);
  padding: 3rem 1rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
  margin-bottom: 2rem;
}

.app-header h1 {
  font-size: 2.25rem;
  font-weight: 600;
  letter-spacing: -0.5px;
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 10px;
  justify-content: center;
}

.app-header p {
  font-size: 1.1rem;
  font-weight: 300;
  opacity: 0.9;
  line-height: 1.5;
}

.app-header i {
  margin-right: 10px;
}

.app-footer {
  background-color: var(--dark-green);
  color: var(--text-light);
  padding: 1.25rem 1rem;
  margin-top: 4rem;
  font-size: 0.9rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.7rem;
}

.footer-top {
  width: 97%;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-top p {
  margin: 0;
}

.app-footer .version {
  opacity: 0.7;
}

/* Disclaimer block */
.footer-disclaimer {
  width: 100%;
  font-size: 0.8rem;
  line-height: 1.45;
  color: rgba(236, 239, 241, 0.85);
  display: flex;
  gap: 0.5rem;
  text-align: center;
}

.footer-disclaimer i {
  color: #c8e6c9; /* soft mint */
  font-size: 0.95rem;
  margin-top: 2px;
}

.footer-disclaimer b {
  color: #ffffff;
  font-weight: 600;
}
/* ───────────────────────────────
   ✳️ Form & Input Components
──────────────────────────────── */
#add-course {
  padding: 0.92rem 1.5rem;
}
#course-selection h2 {
  margin-bottom: 0.5rem;
}
.form-group {
  margin-bottom: 1 rem;
}

label {
  color: var(--dark-green);
  font-size: 0.95rem;
  font-weight: 500;
  display: block;
  margin-bottom: 0.3rem;
}

select {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  font-family: inherit;
  background-color: var(--white);
  border: 2px solid var(--medium-gray);
  border-radius: 8px;
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  background-size: 1rem;
  appearance: none;
  transition: var(--transition);
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%23455a64' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='m6 8 4 4 4-4'/%3e%3c/svg%3e");
}

select:focus {
  border-color: var(--light-green);
  outline: none;
  box-shadow: 0 0 0 3px rgba(46, 125, 50, 0.2);
}

select[multiple] {
  min-height: 150px;
  background-image: none;
  padding: 0.75rem;
}

select[multiple] option {
  padding: 0.5rem;
  border-radius: 4px;
  margin-bottom: 0.25rem;
}

select[multiple] option:hover {
  background-color: var(--mint-green);
}

small {
  display: block;
  font-size: 0.8rem;
  color: var(--dark-gray);
  margin-top: 0.5rem;
  line-height: 1.4;
}

small i {
  margin-right: 5px;
}

/* ===== Course Picker ===== */
.course-picker {
  display: flex;
  gap: 12px;
  align-items: center;
}

#course-dropdown:focus {
  outline: none;
  border-color: #1f8a5b;
  background: white;
}

.dropdown-menu {
  z-index: 500;
}

/* ===== Course Pills ===== */
.course-tabs {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 14px;
  margin-bottom: 14px;
}

.course-tab {
  background: #e7f5f0;
  color: #0f5132;
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 8px;
}

.course-tab span {
  cursor: pointer;
  opacity: 0.6;
}

.course-tab span:hover {
  opacity: 1;
}

/* ───────────────────────────────
   ✳️ Button Components
──────────────────────────────── */
button {
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 500;
  border: none;
  border-radius: 8px;
  letter-spacing: 0.5px;
  cursor: pointer;
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

button i {
  margin-right: 8px;
}

button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.primary-btn {
  background-color: var(--primary-green);
  color: var(--white);
  box-shadow: var(--shadow-sm);
}

.primary-btn:hover:not(:disabled) {
  background-color: var(--dark-green);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.primary-btn:active:not(:disabled) {
  transform: translateY(0);
}

.secondary-btn {
  background-color: var(--white);
  color: var(--primary-green);
  border: 1px solid var(--medium-gray);
}

.secondary-btn:hover:not(:disabled) {
  background-color: var(--light-gray);
  border-color: var(--light-green);
}

.section-header {
  margin-top: 2rem;
}

.action-buttons,
.header-actions,
.export-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  justify-content: space-between;
  margin: 0.5rem 0;
}

/* ───────────────────────────────
   ✳️ Card & Section Components
──────────────────────────────── */
.card {
  background: var(--white);
  border-radius: 12px;
  padding: 2rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow-sm);
  border: 1px solid rgba(0, 0, 0, 0.05);
  transition: var(--transition);
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.course-section {
  margin-bottom: 3rem;
  padding: 2rem;
  border-radius: 12px;
  background-color: var(--white);
  box-shadow: var(--shadow-sm);
}

.course-section h3 {
  color: var(--primary-green);
  font-size: 1.25rem;
  font-weight: 500;
  margin-bottom: 1.5rem;
}

#course-dropdown[multiple] {
  height: auto;
  min-height: 160px;
  padding: 10px;
  border-radius: 10px;
  background: #f8fdfc;
}

.multi-dropdown {
  position: relative;
  width: 100%;
}

.dropdown-toggle {
  width: 100%;
  padding: 12px 16px;
  border-radius: 10px;
  border: 1.5px solid #cfe9e3;
  background: #f7fdfb;
  font-family: Poppins;
  display: flex;
  justify-content: space-between;
  cursor: pointer;
}

.dropdown-menu {
  position: absolute;
  top: 110%;
  width: 100%;
  background: white;
  border-radius: 14px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  padding: 10px;
  z-index: 10;
}

.dropdown-menu label {
  display: flex;
  gap: 10px;
  padding: 8px;
  border-radius: 8px;
  cursor: pointer;
}

.dropdown-menu label:hover {
  background: #f0faf7;
}
.multi-dropdown {
  position: relative;
  z-index: 9999; /* stays above everything */
}

.dropdown-menu {
  z-index: 1000;
  max-height: 260px;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: rgba(0, 128, 0, 0.5) transparent;
}

/* Checkbox alignment */
.dropdown-menu label {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
}
.dropdown-menu::-webkit-scrollbar {
  width: 8px;
}

.dropdown-menu::-webkit-scrollbar-track {
  background: transparent;
}

.dropdown-menu::-webkit-scrollbar-thumb {
  background: rgba(0, 128, 0, 0.35); /* soft green */
  border-radius: 8px;
}

.dropdown-menu::-webkit-scrollbar-thumb:hover {
  background: rgba(0, 128, 0, 0.55);
}

/* Hover */
.dropdown-menu label:hover {
  background: #eefaf6;
}

/* Selected / locked course */
.dropdown-menu label.selected-course {
  background: #e6f7f2;
  opacity: 0.7;
  cursor: not-allowed;
}

/* Add checkmark */
.dropdown-menu label.selected-course::after {
  content: "✓";
  margin-left: auto;
  color: var(--primary-green);
  font-weight: 600;
}

.hidden {
  display: none;
}

/* ───────────────────────────────
   ✳️ Teacher Selection Components
──────────────────────────────── */
.teachers-grid {
  padding-top: 1rem;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 16px;

  max-height: 320px; /* 👈 adjust if needed */
  overflow-y: auto;
  padding-right: 6px; /* space for scrollbar */
}
.teachers-grid::-webkit-scrollbar {
  width: 8px;
}

.teachers-grid::-webkit-scrollbar-track {
  background: transparent;
}

.teachers-grid::-webkit-scrollbar-thumb {
  background: rgba(0, 128, 0, 0.35); /* soft green */
  border-radius: 8px;
}

.teachers-grid::-webkit-scrollbar-thumb:hover {
  background: rgba(0, 128, 0, 0.55);
}

.teachers-grid {
  scrollbar-width: thin;
  scrollbar-color: rgba(0, 128, 0, 0.5) transparent;
}

.teacher-card {
  position: relative;
}

.teacher-card input[type="radio"] {
  position: absolute;
  opacity: 0;
}

.card-ui {
  display: block;
  height: 100%;
  width: 100%;
  background: var(--white);
  border-left: 4px solid var(--light-teal);
  border-radius: 10px;
  box-shadow: var(--shadow-sm);
  padding: 1.25rem;
  box-sizing: border-box;
  cursor: pointer;
  transition: var(--transition);
}

.card-ui:hover {
  transform: translateY(-3px);
  border-left-color: var(--teal);
  box-shadow: var(--shadow-md);
}

.card-ui.selected {
  background-color: var(--mint-green);
  border-left-color: var(--primary-green);
  box-shadow: 0 0 0 3px rgba(46, 125, 50, 0.1);
}

.teacher-name {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 0.75rem;
  line-height: 1.3;
}

.teacher-meta {
  display: flex;
  justify-content: space-between;
  font-size: 0.9rem;
  color: var(--dark-gray);
  margin-bottom: 0.25rem;
}

.teacher-meta .rating {
  color: var(--medium-gray);
}

.teacher-type {
  font-size: 0.75rem;
  color: var(--dark-gray);
  opacity: 0.8;
  font-style: italic;
  margin-top: 0.5rem;
}

.teacher-type-label {
  font-size: 0.85rem;
  font-weight: 600;
  margin: 1.5rem 0 1rem 0;
  padding: 0.75rem 1rem;
  color: var(--dark-green);
  border-left: 4px solid var(--light-green);
  border-radius: 6px;
  background: linear-gradient(to right, var(--mint-green), var(--light-teal));
}

.teacher-section {
  margin-bottom: 2rem;
  padding: 1.5rem;
  background: linear-gradient(to right, #fcfcfc, #f8faf8);
  border-radius: 8px;
  border: 1px solid var(--medium-gray);
}

#teacher-options-container {
  display: block;
}

.no-teacher-msg {
  margin: 10px 0 20px;
  padding: 10px 14px;
  background: #f5f7f6;
  border-left: 4px solid #aaa;
  color: #555;
  font-size: 0.9rem;
  border-radius: 6px;
}

.hidden {
  display: none;
}

/* ===== Teacher Tabs ===== */
#teacher-tabs {
  display: flex;
  flex-wrap: nowrap; /* 🔥 prevent wrapping */
  gap: 12px;
  border-bottom: 2px solid #e6f2ef;
  margin: 10px 0 20px;

  overflow-x: auto; /* 🔥 horizontal slider */
  overflow-y: hidden;
  white-space: nowrap; /* 🔥 force one row */
  scroll-behavior: smooth;

  padding-bottom: 1.5px;

  scrollbar-width: thin; /* Firefox */
  scrollbar-color: var(--teal) transparent;
}

/* Chrome / Edge scrollbar */
#teacher-tabs::-webkit-scrollbar {
  height: 6px;
}

#teacher-tabs::-webkit-scrollbar-track {
  background: transparent;
}

#teacher-tabs::-webkit-scrollbar-thumb {
  background: linear-gradient(135deg, var(--primary-green), var(--teal));
  border-radius: 10px;
}

#teacher-tabs button {
  flex-shrink: 0;
  white-space: nowrap;

  background: transparent;
  border: none;
  padding: 8px 20px;
  font-family: "Poppins", sans-serif;
  font-size: 0.9rem;
  cursor: pointer;
  color: #6b7280;
  position: relative;
}

#teacher-tabs button.active {
  background-color: var(--mint-green);
  border-radius: 10px 10px 0 0;
  color: #0f5132;
  font-weight: 600;
  transition: ease-in-out;
}

#teacher-tabs button.active::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 3px;
  background: #1f8a5b;
  border-radius: 4px;
}

/* ───────────────────────────────
   ✳️ Timetable Components
──────────────────────────────── */
.timetable-container {
  margin-top: 2.5rem;
  padding: 1.5rem;
  overflow-x: auto;
  background: var(--white);
  border-radius: 12px;
  box-shadow: var(--shadow-sm);
  width: 100%;
  scrollbar-width: thin;
  scrollbar-color: rgba(0, 128, 0, 0.5) transparent;
}

.timetable-grid {
  display: grid;
  grid-template-columns: minmax(60px, 80px) repeat(12, 140px);
  gap: 2px;
  min-width: max-content;
}

.timetable-cell {
  position: relative;
  padding: 0.75rem;
  min-height: 70px;
  min-height: 80px;
  background-color: var(--white);
  border: 1px solid #e6eeee;
}

.time-header,
.day-header {
  font-size: smaller;
  font-weight: 500;
  padding: 0;
  background-color: var(--light-teal);
  display: flex;
  align-items: center;
  justify-content: center;
}

.time-header {
  text-align: right;
  justify-content: flex-end;
  padding: 1rem;
}

.lab-only-time {
  background-color: #ffeeee;
  font-weight: bold;
}

.course-slot {
  background: #ecf6f2;
  border-left: 4px solid var(--primary-green);
  border-radius: 6px;
  padding: 6px 8px;
  font-size: 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 2px;
  margin-bottom: 10px;
}

.theory-slot {
  background-color: rgba(46, 125, 50, 0.08);
  border-left: 3px solid var(--primary-green);
  margin-bottom: 10px;
}

.lab-slot {
  background-color: rgba(0, 137, 123, 0.08);
  border-left: 3px solid var(--teal);
  margin-bottom: 10px;
}

.conflict-slot {
  background-color: rgba(229, 57, 53, 0.08);
  border-left: 3px solid var(--error-red);
  margin-bottom: 10px;
}

.slot-code-label {
  position: absolute;
  bottom: 4px;
  right: 6px;
  font-size: 0.5rem;
  color: #777;
  opacity: 0.6;
  pointer-events: none;
  white-space: nowrap;
}

.timetable-cell:has(.course-slot) .slot-code-label {
  opacity: 0.25;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  margin-top: 0.5rem;
  padding: 0 1rem;
  max-height: 44px;
  background: var(--white);
  border-radius: 8px;
  box-shadow: var(--shadow-sm);
}

.legend span {
  display: flex;
  align-items: center;
  font-size: 0.9rem;
  gap: 0.5rem;
}

.theory-legend {
  color: var(--primary-green);
}

.lab-legend {
  color: var(--teal);
}

.conflict-legend {
  color: var(--error-red);
}

.conflict-warnings {
  margin-top: 1.5rem;
  padding: 1rem;
  border-radius: 8px;
  border-left: 3px solid var(--error-red);
  background-color: rgba(229, 57, 53, 0.08);
}

.conflict-warning {
  font-size: 0.9rem;
  color: var(--error-red);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.conflict-warnings:has(.fa-exclamation-triangle) .conflict-warning {
  margin-bottom: 0.5rem;
}

.total-credits {
  margin-top: 1rem;
  font-size: 1.125rem;
  font-weight: bold;
  color: var(--primary-green);
  padding: 1rem;
  background: var(--mint-green);
  border-radius: 8px;
  text-align: center;
}

.course-code {
  font-weight: 600;
  color: #134e3a;
}

.course-slot-code {
  font-size: 0.6rem;
  opacity: 0.7;
}

/* ───────────────────────────────
   ✳️ Table Components
──────────────────────────────── */
.selected-teachers-table {
  margin-bottom: 3rem;
  animation: fadeIn 0.5s ease-in-out;
}

.selected-teachers-table h3 {
  color: var(--primary-green);
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.selected-teachers-table h3 i {
  color: var(--teal);
}

.table-container {
  overflow-x: auto;
  border-radius: 8px;
  border: 1px solid var(--medium-gray);
  box-shadow: var(--shadow-sm);
}

.teachers-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  background: var(--white);
  min-width: 600px;
}

.teachers-table th {
  background: var(--primary-green);
  color: var(--white);
  font-weight: 500;
  padding: 1.25rem 1rem;
  text-align: left;
  border-bottom: 2px solid var(--dark-green);
  white-space: nowrap;
}

.teachers-table td {
  padding: 1rem;
  border-bottom: 1px solid var(--medium-gray);
  vertical-align: top;
}

.teachers-table tbody tr:nth-child(even) {
  background-color: var(--mint-green);
}

.teachers-table tbody tr:hover {
  background-color: var(--light-teal);
}

.teachers-table tfoot {
  background-color: var(--light-gray);
  font-weight: 600;
}

.teachers-table tfoot td {
  border-bottom: none;
  border-top: 2px solid var(--medium-gray);
}

/* Course code styling */
.teachers-table td:first-child {
  font-weight: 600;
  color: var(--dark-green);
}

/* Teacher name styling */
.teachers-table td:nth-child(3),
.teachers-table td:nth-child(5) {
  font-weight: 500;
  color: var(--text-dark);
}

/* Slot styling */
.teachers-table td:nth-child(4),
.teachers-table td:nth-child(6) {
  font-weight: 600;
  color: var(--dark-green);
}

/* Credits styling */
.teachers-table td:last-child {
  text-align: center;
  font-weight: 600;
  color: var(--primary-green);
  font-size: 1.1rem;
}

/* Empty state */
.empty-selection {
  text-align: center;
  padding: 3rem;
  color: var(--dark-gray);
  font-style: italic;
}

.empty-selection i {
  font-size: 2rem;
  color: var(--medium-gray);
  margin-bottom: 1rem;
  display: block;
}

/* /* ───────────────────────────────
   🔍 Sorting & Search Controls
──────────────────────────────── */

.sorting-controls {
  margin: 1rem 0 2rem;
  padding: 1rem 1.25rem;
  border-radius: 12px;
  background: linear-gradient(135deg, #e8f5f1, #f3fbf8);
  border-left: 6px solid var(--primary-green);
  box-shadow: var(--shadow-sm);
  position: relative;
  z-index: 2;
}

.sort-options {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

/* ─── Search Bar ─── */

.search-bar {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.teacher-search {
  flex: 1;
  min-width: 220px;
  padding: 0.7rem 1rem;
  border-radius: 10px;
  border: 1.5px solid #cfe9e3;
  background: var(--white);
  font-family: Poppins, sans-serif;
  font-size: 0.9rem;
  color: var(--text-dark);
  transition: var(--transition);
}

.teacher-search:focus {
  border-color: var(--light-green);
  outline: none;
  box-shadow: 0 0 0 3px rgba(46, 125, 50, 0.15);
}

.teacher-search::placeholder {
  color: #8fbfb3;
}

/* ─── Sorting Row ─── */
.sorting {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  width: 100%;
}

/* Labels */
.sort-label {
  font-weight: 600;
  color: var(--dark-green);
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--white);
  padding: 0.55rem 0.9rem;
  border-radius: 8px;
  box-shadow: var(--shadow-sm);
  white-space: nowrap;
}

.sort-label i {
  color: var(--teal);
  font-size: 1.05rem;
}

/* Sorting form */
.sorting-form {
  display: flex;
  gap: 12px;
  flex-direction: row;
  width: auto;
  flex: 1;
  min-width: 0;
}

/* Select dropdowns */
.sort-criteria,
.sort-order {
  flex: 1;
  padding: 0.7rem 1rem;
  border: 2px solid var(--medium-gray);
  border-radius: 8px;
  background: var(--white);
  font-size: 0.9rem;
  font-family: inherit;
  color: var(--text-dark);
  transition: var(--transition);
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%232e8b57' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='m6 8 4 4 4-4'/%3e%3c/svg%3e");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  background-size: 1rem;
  appearance: none;
  cursor: pointer;
  min-width: 160px;
  box-shadow: var(--shadow-sm);
}

.sort-criteria:focus,
.sort-order:focus {
  border-color: var(--light-green);
  outline: none;
  box-shadow:
    0 0 0 3px rgba(46, 125, 50, 0.2),
    var(--shadow-sm);
}

.sort-criteria:hover,
.sort-order:hover {
  border-color: var(--teal);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* Apply button */
.sort-apply-btn {
  flex-shrink: 0;
  padding: 0.7rem 1.4rem;
  font-size: 0.9rem;
  font-weight: 500;
  background: linear-gradient(135deg, var(--primary-green), var(--teal));
  color: var(--white);
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 0.5rem;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
  white-space: nowrap;
}

.sort-apply-btn::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.25),
    transparent
  );
  transition: left 0.5s;
}

.sort-apply-btn:hover {
  background: linear-gradient(135deg, var(--dark-green), var(--primary-green));
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.sort-apply-btn:hover::before {
  left: 100%;
}

.sort-apply-btn:active {
  transform: translateY(0);
}

/* ─── Sort Indicator ─── */
.sort-indicator {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  color: var(--primary-green);
  font-size: 0.85rem;
  padding: 0.45rem 0.9rem;
  background: var(--white);
  border-radius: 20px;
  border: 2px solid var(--light-green);
  margin-left: auto;
  box-shadow: var(--shadow-sm);
  animation: pulse 2s infinite;
}

.sort-indicator i {
  color: var(--teal);
  animation: bounce 2s infinite;
}

/* ─── State Classes ─── */

.sorting-controls.active {
  background: linear-gradient(135deg, var(--light-teal), var(--mint-green));
  border-left-color: var(--teal);
  box-shadow: 0 0 0 3px rgba(0, 137, 123, 0.1);
}

.sorting-controls.success {
  border-left-color: var(--light-green);
  background: linear-gradient(135deg, var(--mint-green), #e8f5e9);
}

.sorting-controls.success .sort-indicator {
  border-color: var(--light-green);
  color: var(--dark-green);
}

.sorting-controls.loading {
  opacity: 0.7;
  pointer-events: none;
}

.sorting-controls.loading::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.4),
    transparent
  );
  animation: loading 1.5s infinite;
}

/* ───────────────────────────────
   🔄 Animations
──────────────────────────────── */

@keyframes pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(46, 125, 50, 0.25);
  }
  70% {
    box-shadow: 0 0 0 6px rgba(46, 125, 50, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(46, 125, 50, 0);
  }
}

@keyframes bounce {
  0%,
  20%,
  50%,
  80%,
  100% {
    transform: translateY(0);
  }
  40% {
    transform: translateY(-3px);
  }
  60% {
    transform: translateY(-2px);
  }
}

@keyframes loading {
  0% {
    transform: translateX(-100%);
  }
  100% {
    transform: translateX(100%);
  }
}

.sorting-controls.sort-applied {
  animation: sortApplied 0.5s ease-in-out;
}

/* ───────────────────────────────
   ✳️ Responsive Design
──────────────────────────────── */
@media (max-width: 768px) {
  .app-main {
    padding: 1.5rem 1rem;
  }

  .app-header {
    padding: 2rem 1rem;
    margin-bottom: 1.5rem;
  }

  .app-header h1 {
    font-size: 1.75rem;
  }

  .app-header p {
    font-size: 1rem;
  }

  .card {
    padding: 1.5rem;
    margin-bottom: 1rem;
  }

  .course-section {
    padding: 1.5rem;
    margin-bottom: 1rem;
  }

  .teachers-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
    margin-top: 1rem;
  }

  .card-ui {
    padding: 1rem;
    font-size: 0.9rem;
  }

  .teacher-name {
    font-size: 1rem;
  }

  .teacher-meta {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.25rem;
    font-size: 0.85rem;
  }

  .teacher-type-label {
    margin: 1rem 0 0.75rem 0;
    padding: 0.5rem 0.75rem;
    font-size: 0.8rem;
  }

  .timetable-grid {
    grid-template-columns: 60px repeat(12, 1fr);
    font-size: 0.75rem;
  }

  .timetable-cell {
    padding: 0.5rem;
    min-height: 60px;
  }

  .course-slot {
    font-size: 0.7rem;
    padding: 0.4rem;
  }

  .time-header,
  .day-header {
    padding: 0.5rem;
    font-size: 0.8rem;
  }

  .teachers-table {
    font-size: 0.8rem;
    min-width: 500px;
  }

  .teachers-table th,
  .teachers-table td {
    padding: 0.75rem 0.5rem;
  }

  .teachers-table th:nth-child(2),
  .teachers-table td:nth-child(2) {
    max-width: 100px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .action-buttons,
  .header-actions,
  .export-buttons {
    flex-direction: column;
    gap: 0.75rem;
  }

  .export-buttons button {
    width: 100%;
  }

  .app-footer {
    flex-direction: column;
    gap: 0.5rem;
    padding: 1.25rem;
    margin-top: 3rem;
  }

  .legend {
    flex-direction: column;
    gap: 1rem;
    padding: 1rem;
  }

  .sorting-controls {
    margin: 1rem 0;
    padding: 1rem;
  }

  .sort-options {
    flex-direction: column;
    align-items: stretch;
    gap: 0.75rem;
  }

  .sort-label {
    justify-content: center;
    text-align: center;
    font-size: 0.9rem;
    padding: 0.75rem;
  }

  .sort-criteria,
  .sort-order {
    width: 100%;
    min-width: auto;
    font-size: 0.85rem;
    padding: 0.875rem 1rem;
  }

  .sort-apply-btn {
    width: 100%;
    justify-content: center;
    font-size: 0.85rem;
    padding: 0.875rem 1.5rem;
  }

  .sort-indicator {
    margin-left: 0;
    justify-content: center;
    font-size: 0.8rem;
    padding: 0.75rem 1rem;
  }

  .sort-criteria-container::after,
  .sort-order-container::after {
    right: 1rem;
  }

  .section-header {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 1rem;
  }

  .section-header h2 {
    text-align: center;
  }

  .header-actions {
    width: 100%;
    align-items: stretch;
  }

  .header-actions > * {
    width: 100%;
  }

  .header-actions button {
    width: 100%;
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .app-main {
    padding: 1rem 0.75rem;
  }

  .app-header {
    padding: 1.5rem 0.75rem;
  }

  .app-header h1 {
    font-size: 1.5rem;
  }

  .card {
    padding: 1.25rem;
    border-radius: 10px;
  }

  .course-section {
    padding: 1.25rem;
    border-radius: 10px;
  }

  .card-ui {
    padding: 0.875rem;
    font-size: 0.85rem;
    border-left-width: 3px;
  }

  .teacher-name {
    font-size: 0.95rem;
  }

  .teacher-meta {
    font-size: 0.8rem;
  }

  .timetable-container {
    padding: 1rem;
    margin-left: -0.5rem;
    margin-right: -0.5rem;
    width: calc(100% + 1rem);
    border-radius: 8px;
  }

  .timetable-grid {
    grid-template-columns: 50px repeat(12, 1fr);
    font-size: 0.7rem;
  }

  .timetable-cell {
    padding: 0.375rem;
    min-height: 55px;
  }

  .course-slot {
    font-size: 0.65rem;
    padding: 0.3rem;
  }

  .table-container {
    margin-left: -0.5rem;
    margin-right: -0.5rem;
    width: calc(100% + 1rem);
    border-radius: 6px;
  }

  .teachers-table {
    font-size: 0.75rem;
    min-width: 450px;
  }

  .teachers-table th,
  .teachers-table td {
    padding: 0.5rem 0.375rem;
  }

  .selected-teachers-table h3 {
    font-size: 1.1rem;
  }

  .empty-selection {
    padding: 2rem 1rem;
  }

  .empty-selection i {
    font-size: 1.5rem;
  }

  .conflict-warnings {
    padding: 1rem;
  }

  .total-credits {
    font-size: 1rem;
    padding: 0.75rem;
  }

  .sorting-controls {
    padding: 0.875rem;
    border-radius: 10px;
  }

  .sort-criteria,
  .sort-order {
    padding: 0.75rem 0.875rem;
    font-size: 0.8rem;
  }

  .sort-apply-btn {
    padding: 0.75rem 1.25rem;
    font-size: 0.8rem;
  }

  .sort-label {
    font-size: 0.85rem;
    padding: 0.625rem 0.875rem;
  }

  .sort-indicator {
    font-size: 0.75rem;
    padding: 0.625rem 0.875rem;
  }
}

/* Small height devices */
@media (max-height: 600px) and (max-width: 768px) {
  .app-header {
    padding: 1.5rem 1rem;
  }

  .app-main {
    padding: 1rem;
  }

  .card-ui {
    padding: 0.75rem;
    max-height: 80px;
    overflow: hidden;
  }
}

/* Top action buttons wrapper */
.top-actions {
  position: fixed;
  top: 18px;
  right: 18px;
  display: flex;
  gap: 10px;
  z-index: 10000;
}

/* Video button */
.video-btn {
  width: 40px;
  height: 40px;
  border-radius: 100%;
  padding: 10px;
  border: none;
  background: #444;
  color: white;
  font-size: 1rem;
  cursor: pointer;
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.video-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 22px rgba(0, 0, 0, 0.2);
}

/* Video overlay */
.video-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(4px);
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.video-overlay.hidden {
  display: none;
}

.video-content {
  width: 100%;
  max-width: 1000px;
  background: #ffffff;
  border-radius: 10px;
  box-shadow: 0 18px 45px rgba(0, 0, 0, 0.25);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  animation: helpFadeIn 0.25s ease;
}

.video-header {
  padding: 14px 18px;
  background: linear-gradient(135deg, var(--primary-green), var(--teal));
  color: white;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.video-header h2 {
  font-size: 1.05rem;
  font-weight: 600;
  margin: 0;
}

.close-video {
  background: transparent;
  border: none;
  font-size: 1.6rem;
  color: white;
  cursor: pointer;
  line-height: 1;
}

#demo-video {
  width: 100%;
  max-height: 70vh;
  background: black;
}

.help-btn {
  width: 40px;
  height: 40px;
  padding: 9px;
  border-radius: 50%;
  border: none;
  background: #444;
  color: white;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.15);
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.help-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 22px rgba(0, 0, 0, 0.2);
}

.help-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(4px);
  z-index: 10000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.help-overlay.hidden {
  display: none;
}

.help-content {
  width: 100%;
  max-width: 720px;
  max-height: 90vh;
  background: #ffffff;
  border-radius: 10px;
  box-shadow: 0 18px 45px rgba(0, 0, 0, 0.25);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  animation: helpFadeIn 0.25s ease;
}

@keyframes helpFadeIn {
  from {
    opacity: 0;
    transform: translateY(12px) scale(0.96);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.help-header {
  padding: 18px 22px;
  background: linear-gradient(135deg, var(--primary-green), var(--teal));
  color: white;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.help-header h2 {
  font-size: 1.2rem;
  font-weight: 600;
  margin: 0;
}

.close-help {
  background: transparent;
  border: none;
  font-size: 1.6rem;
  color: white;
  cursor: pointer;
  line-height: 1;
}

.help-body {
  padding: 20px 22px;
  overflow-y: auto;
  font-size: 0.95rem;
  line-height: 1.55;
  color: #333;
  scrollbar-width: thin;
  scrollbar-color: rgba(0, 128, 0, 0.5) transparent;
}

.help-body h3 {
  font-size: 1rem;
  margin: 16px 0 6px;
  color: #2c3e50;
}

.help-body p {
  margin: 0 0 10px;
}

.help-body ul {
  padding-left: 18px;
  margin: 6px 0 12px;
}

.help-body li {
  margin-bottom: 6px;
}

.help-body b {
  color: #27ae60;
}

.help-body::-webkit-scrollbar {
  width: 8px;
}

.help-body::-webkit-scrollbar-track {
  background: transparent;
}

.help-body::-webkit-scrollbar-thumb {
  background: rgba(0, 128, 0, 0.35); /* soft green */
  border-radius: 8px;
}

.help-body::-webkit-scrollbar-thumb:hover {
  background: rgba(0, 128, 0, 0.55);
}

/* ===== Export Mode ===== */
.export-mode #export-wrapper {
  width: 1800px; /* adjust if needed */
  max-width: none;
  margin: 0 auto;
}

.export-mode .timetable-container {
  width: 100%;
  overflow: visible !important;
}

.export-mode .timetable-grid {
  min-width: 100% !important;
}

.export-mode .table-container {
  overflow: visible !important;
}

.export-mode body {
  overflow: hidden;
}