/* CSS Custom Properties for Theming */
:root {
  /* Light theme colors - WCAG 2.1 AA compliant */
  --bg-primary: #eef2f5;
  --bg-secondary: #ffffff;
  --text-primary: #1a1a1a; /* Improved contrast */
  --text-secondary: #2d2d2d; /* Improved contrast */
  --text-muted: #4a4a4a; /* Improved contrast */
  --border-color: #666666; /* Improved contrast */
  --shadow-color: rgba(0, 0, 0, 0.1);
  --shadow-color-light: rgba(0, 0, 0, 0.05);
  --navbar-bg: #003366;
  --button-primary: #0066cc;
  --button-primary-hover: #004999;
  --button-secondary: #7a212a;
  --button-secondary-hover: #b52a37;
  --preset-bg: #004080;
  --preset-hover: #003060;
  --week-header-teaching: #004080;
  --week-header-reading: #d97706; /* Improved contrast */
  --week-header-assessment: #dc2626; /* Improved contrast */
  --week-header-break: #9333ea; /* Improved contrast */
  --toast-bg: #1f2937; /* Improved contrast */
  --modal-overlay: rgba(0, 0, 0, 0.5);
  --modal-bg: #ffffff;
  --input-bg: #ffffff;
  --input-border: #666666; /* Improved contrast */
  --input-focus: #0073e6;
  --input-focus-shadow: rgba(0, 115, 230, 0.3);
  
  /* Accessibility focus indicators */
  --focus-outline: 3px solid #0073e6;
  --focus-outline-offset: 2px;
  --focus-ring: 0 0 0 3px rgba(0, 115, 230, 0.3);
  
  /* Hover backgrounds */
  --hover-bg: rgba(0, 0, 0, 0.05);
  
  /* Skip link styles */
  --skip-link-bg: #0073e6;
  --skip-link-color: #ffffff;
  --skip-link-hover-bg: #0056b3;
}

/* Dark theme colors - WCAG 2.1 AA compliant */
[data-theme="dark"] {
  --bg-primary: #1a1a1a;
  --bg-secondary: #2d2d2d;
  --text-primary: #ffffff;
  --text-secondary: #e5e7eb; /* Improved contrast */
  --text-muted: #d1d5db; /* Improved contrast */
  --border-color: #6b7280; /* Improved contrast */
  --shadow-color: rgba(0, 0, 0, 0.3);
  --shadow-color-light: rgba(0, 0, 0, 0.2);
  --navbar-bg: #1a1a1a;
  --button-primary: #0073e6;
  --button-primary-hover: #0056b3;
  --button-secondary: #dc3545;
  --button-secondary-hover: #c82333;
  --preset-bg: #2d2d2d;
  --preset-hover: #404040;
  --week-header-teaching: #0073e6;
  --week-header-reading: #f59e0b; /* Improved contrast */
  --week-header-assessment: #ef4444; /* Improved contrast */
  --week-header-break: #a855f7; /* Improved contrast */
  --toast-bg: #374151; /* Improved contrast */
  --modal-overlay: rgba(0, 0, 0, 0.7);
  --modal-bg: #2d2d2d;
  --input-bg: #404040;
  --input-border: #6b7280; /* Improved contrast */
  --input-focus: #0073e6;
  --input-focus-shadow: rgba(0, 115, 230, 0.4);
  
  /* Dark theme focus indicators */
  --focus-outline: 3px solid #0073e6;
  --focus-outline-offset: 2px;
  --focus-ring: 0 0 0 3px rgba(0, 115, 230, 0.4);
  
  /* Dark theme hover backgrounds */
  --hover-bg: rgba(255, 255, 255, 0.1);
  
  /* Dark theme skip link styles */
  --skip-link-bg: #0073e6;
  --skip-link-color: #ffffff;
  --skip-link-hover-bg: #0056b3;
}

[data-theme="dark"] .dropdown-content {
  background: #374151; /* Improved contrast */
}

[data-theme="dark"] .dropdown-content a {
  color: #f9fafb; /* Improved contrast */
}

/* WCAG 2.1 AA Accessibility Improvements */

/* Skip to main content link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 6px;
  background: var(--skip-link-bg);
  color: var(--skip-link-color);
  padding: 8px 16px;
  text-decoration: none;
  border-radius: 4px;
  font-weight: 600;
  z-index: 10000;
  transition: top 0.3s ease;
}

.skip-link:focus {
  top: 6px;
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}

/* Focus indicators for all interactive elements */
button:focus,
input:focus,
select:focus,
textarea:focus,
a:focus,
[tabindex]:focus {
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}

/* Remove default focus outline and use custom one */
button:focus,
input:focus,
select:focus,
textarea:focus,
a:focus {
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}

/* High contrast focus for keyboard navigation */
*:focus-visible {
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}

/* Theme transition */
* {
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

/* Base accessibility improvements */
body { 
  font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, 'Roboto', sans-serif; 
  padding: 0 0 80px 0; /* top, right, bottom, left */
  background: var(--bg-primary); 
  margin: 0; 
  color: var(--text-primary);
  line-height: 1.6; /* Improved readability */
  font-size: 16px; /* Minimum readable font size */
}

/* Improved heading hierarchy and contrast */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  line-height: 1.3;
  margin-top: 1.5em;
  margin-bottom: 0.5em;
}

h1 { 
  text-align: center; 
  color: var(--text-primary); 
  margin-bottom: 30px; 
  font-size: 2rem;
  font-weight: 700;
}

h2 {
  font-size: 1.5rem;
  font-weight: 600;
}

h3 {
  font-size: 1.25rem;
  font-weight: 600;
}

/* Improved label accessibility */
label { 
  font-weight: 500; 
  display: block; 
  margin-bottom: 8px; 
  color: var(--text-primary); 
  font-size: 1rem;
}

/* Required field indicators */
label.required::after {
  content: " *";
  color: #dc2626;
  font-weight: bold;
}

[data-theme="dark"] label.required::after {
  color: #ef4444;
}

/* Improved form controls */
input, select, textarea {
  padding: 12px 16px;
  margin-bottom: 16px;
  border-radius: 8px;
  border: 2px solid var(--input-border);
  font-size: 16px; /* Minimum readable font size */
  width: 100%;
  box-sizing: border-box;
  background-color: var(--input-bg);
  color: var(--text-primary);
  line-height: 1.5;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

input:focus,
select:focus,
textarea:focus {
  border-color: var(--input-focus);
  box-shadow: var(--focus-ring);
  outline: none;
}

/* Improved select styling */
select {
  appearance: none;
  -webkit-appearance: none;
  -moz-appearance: none;
  background-color: var(--input-bg);
  border: 2px solid var(--input-border);
  padding: 12px 16px;
  font-size: 16px;
  border-radius: 8px;
  background-image: url("data:image/svg+xml;utf8,<svg fill='%23666' height='16' viewBox='0 0 20 20' width='16' xmlns='http://www.w3.org/2000/svg'><path d='M5.516 7.548l4.484 4.484 4.484-4.484L15.484 9 10 14.484 4.516 9z'/></svg>");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 16px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

[data-theme="dark"] select {
  background-image: url("data:image/svg+xml;utf8,<svg fill='%23fff' height='16' viewBox='0 0 20 20' width='16' xmlns='http://www.w3.org/2000/svg'><path d='M5.516 7.548l4.484 4.484 4.484-4.484L15.484 9 10 14.484 4.516 9z'/></svg>");
}

/* Improved date input */
input[type="date"] {
  appearance: none;
  -webkit-appearance: none;
  background-color: var(--input-bg);
  border: 2px solid var(--input-border);
  padding: 12px 16px;
  font-size: 16px;
  border-radius: 8px;
  box-sizing: border-box;
  height: 48px; 
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
  color: var(--text-primary);
}

input[type="date"]:focus {
  border-color: var(--input-focus);
  box-shadow: var(--focus-ring);
  outline: none;
}

/* Fix for Chrome calendar icon spacing */
input[type="date"]::-webkit-calendar-picker-indicator {
  filter: invert(0.5);
  cursor: pointer;
  margin-left: 8px;
  width: 20px;
  height: 20px;
}

/* Dark mode calendar icon */
[data-theme="dark"] input[type="date"]::-webkit-calendar-picker-indicator {
  filter: invert(1);
}

/* Modern responsive navbar */
.main-navbar {
  background: var(--navbar-bg);
  padding: 8px 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: white;
  width: 100%;
  margin: 0;
  box-sizing: border-box;
  min-height: 56px;
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* Hamburger menu button */
.hamburger-menu {
  display: none;
  flex-direction: column;
  cursor: pointer;
  padding: 8px;
  border: none;
  background: none;
  color: white;
  gap: 4px;
  min-width: 40px;
  min-height: 40px;
  justify-content: center;
  align-items: center;
  border-radius: 6px;
  transition: all 0.2s ease;
}

.hamburger-menu:hover {
  background-color: rgba(255, 255, 255, 0.15);
}

.hamburger-menu:focus {
  background-color: rgba(255, 255, 255, 0.2);
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}

.hamburger-menu span {
  width: 20px;
  height: 2px;
  background-color: white;
  transition: all 0.3s ease;
  border-radius: 1px;
}

.hamburger-menu.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.hamburger-menu.active span:nth-child(2) {
  opacity: 0;
}

.hamburger-menu.active span:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -6px);
}

.main-navbar .navbar-title {
  display: flex;
  flex-direction: row;
  align-items: center;
  color: white;
  gap: 8px;
  font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, sans-serif;
  flex-shrink: 0;
}

.main-navbar .title-main {
  font-weight: 700;
  font-size: 1.3rem;
  letter-spacing: -0.5px;
  white-space: nowrap;
}

.main-navbar .title-subtitle {
  font-size: 0.9rem;
  font-weight: 500;
  opacity: 0.9;
  letter-spacing: -0.3px;
  white-space: nowrap;
}

.main-navbar .title-separator {
  opacity: 0.6;
  font-size: 1rem;
  font-weight: 300;
}

.main-navbar .navbar-links {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: flex-end;
  flex: 1;
  margin-left: 16px;
}

.main-navbar .navbar-links a {
  color: white;
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  padding: 8px 12px;
  border-radius: 6px;
  transition: all 0.2s ease;
  white-space: nowrap;
  display: flex;
  align-items: center;
  gap: 6px;
}

.main-navbar .navbar-links a:hover {
  background-color: rgba(255, 255, 255, 0.15);
  color: white;
  transform: translateY(-1px);
}

.main-navbar .navbar-links a:focus {
  background-color: rgba(255, 255, 255, 0.2);
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}

/* Responsive navbar */
@media (max-width: 888px) {
  .main-navbar {
    padding: 6px 12px;
  }
  
  .main-navbar .navbar-title {
    gap: 6px;
  }
  
  .main-navbar .title-main {
    font-size: 1.2rem;
  }
  
  .main-navbar .title-subtitle {
    font-size: 0.8rem;
  }
  
  .main-navbar .title-separator {
    font-size: 0.9rem;
  }
  
  .main-navbar .navbar-links {
    gap: 8px;
    margin-left: 12px;
  }
  
  .main-navbar .navbar-links a {
    font-size: 0.85rem;
    padding: 6px 10px;
  }
}

@media (max-width: 640px) {
  .main-navbar {
    padding: 4px 8px;
  }
  
  .main-navbar .navbar-title {
    gap: 4px;
  }
  
  .main-navbar .title-main {
    font-size: 1.1rem;
  }
  
  .main-navbar .title-subtitle {
    font-size: 0.75rem;
  }
  
  .main-navbar .title-separator {
    font-size: 0.8rem;
  }
  
  .main-navbar .navbar-links {
    gap: 6px;
    margin-left: 8px;
  }
  
  .main-navbar .navbar-links a {
    font-size: 0.8rem;
    padding: 5px 8px;
  }
}

@media (max-width: 480px) {
  .main-navbar .title-subtitle {
    display: none;
  }
  
  .main-navbar .title-separator {
    display: none;
  }
  
  .main-navbar .navbar-links {
    gap: 4px;
  }
  
  .main-navbar .navbar-links a {
    font-size: 0.75rem;
    padding: 4px 6px;
  }
}

/* Mobile hamburger menu */
@media (max-width: 888px) {
  .hamburger-menu {
    display: flex;
  }
  
  .main-navbar .navbar-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--navbar-bg);
    flex-direction: column;
    gap: 0;
    margin: 0;
    padding: 0;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    max-height: 0;
    overflow: hidden;
  }
  
  .main-navbar .navbar-links.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
    max-height: 400px;
  }
  
  .main-navbar .navbar-links a,
  .main-navbar .navbar-links .dropdown {
    width: 100%;
    padding: 12px 16px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 1rem;
    justify-content: flex-start;
  }
  
  .main-navbar .navbar-links a:last-child,
  .main-navbar .navbar-links .dropdown:last-child {
    border-bottom: none;
  }
  
  .main-navbar .navbar-links .dropdown-btn {
    width: 100%;
    justify-content: flex-start;
    padding: 12px 16px;
    font-size: 1rem;
  }
  
  .main-navbar .navbar-links .dropdown-content {
    position: static;
    background: rgba(0, 0, 0, 0.2);
    box-shadow: none;
    border: none;
    border-radius: 0;
    margin: 0;
    width: 100%;
    min-width: 100%;
  }
  
  .main-navbar .navbar-links .dropdown-content a {
    padding: 10px 20px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    color: white !important;
  }
  
  .main-navbar .navbar-links .dropdown-content a:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: white !important;
  }
  
  .theme-toggle {
    position: absolute;
    right: 16px;
    top: 50%;
    transform: translateY(-50%);
  }
}

@media (max-width: 480px) {
  .main-navbar .navbar-links a,
  .main-navbar .navbar-links .dropdown {
    padding: 10px 14px;
    font-size: 0.95rem;
  }
  
  .main-navbar .navbar-links .dropdown-btn {
    padding: 10px 14px;
    font-size: 0.95rem;
  }
  
  .main-navbar .navbar-links .dropdown-content a {
    padding: 8px 16px;
    font-size: 0.9rem;
  }
  
  .theme-toggle {
    right: 12px;
  }
}

/* Modern theme toggle button */
.theme-toggle {
  background: none;
  border: none;
  color: white;
  font-size: 1.1rem;
  cursor: pointer;
  padding: 8px;
  border-radius: 6px;
  transition: all 0.2s ease;
  margin-left: 8px;
  min-width: 40px;
  min-height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.theme-toggle:hover {
  background-color: rgba(255, 255, 255, 0.15);
  transform: translateY(-1px) scale(1.05);
}

.theme-toggle:focus {
  background-color: rgba(255, 255, 255, 0.2);
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}

/* Responsive theme toggle */
@media (max-width: 888px) {
  .theme-toggle {
    font-size: 1rem;
    padding: 6px;
    margin-left: 6px;
    min-width: 36px;
    min-height: 36px;
  }
}

@media (max-width: 640px) {
  .theme-toggle {
    font-size: 0.9rem;
    padding: 5px;
    margin-left: 4px;
    min-width: 32px;
    min-height: 32px;
  }
}

@media (max-width: 480px) {
  .theme-toggle {
    font-size: 0.85rem;
    padding: 4px;
    margin-left: 3px;
    min-width: 28px;
    min-height: 28px;
  }
}

.preview-controls {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 20px;
}

#previewFrame {
  width: 100%;
  height: 600px;
  border: 1px solid var(--border-color);
  background: var(--bg-secondary);
  border-radius: 8px;
  box-shadow: 0 2px 8px var(--shadow-color);
  margin-top: 20px;
}

.week-header.teaching { 
  background-color: var(--week-header-teaching); 
  color: #fff; 
}
.week-header.reading { 
  background-color: var(--week-header-reading); 
  color: #fff; 
}
.week-header.assessment { 
  background-color: var(--week-header-assessment); 
  color: #fff; 
}
.week-header.break { 
  background-color: var(--week-header-break); 
  color: #fff; 
}

/* Row highlighting for preset page */
.week-row.row-teaching, tr.week-row.row-teaching {
  background-color: rgba(0, 64, 128, 0.18) !important;
  border-left: 4px solid var(--week-header-teaching) !important;
}

.week-row.row-reading, tr.week-row.row-reading {
  background-color: rgba(240, 173, 78, 0.18) !important;
  border-left: 4px solid var(--week-header-reading) !important;
}

.week-row.row-assessment, tr.week-row.row-assessment {
  background-color: rgba(220, 53, 69, 0.18) !important;
  border-left: 4px solid var(--week-header-assessment) !important;
}

.week-row.row-break, tr.week-row.row-break {
  background-color: rgba(189, 97, 217, 0.18) !important;
  border-left: 4px solid var(--week-header-break) !important;
}

[data-theme="dark"] .week-row.row-teaching, [data-theme="dark"] tr.week-row.row-teaching {
  background-color: rgba(0, 115, 230, 0.25) !important;
  border-left: 4px solid var(--week-header-teaching) !important;
}

[data-theme="dark"] .week-row.row-reading, [data-theme="dark"] tr.week-row.row-reading {
  background-color: rgba(255, 193, 7, 0.25) !important;
  border-left: 4px solid var(--week-header-reading) !important;
}

[data-theme="dark"] .week-row.row-assessment, [data-theme="dark"] tr.week-row.row-assessment {
  background-color: rgba(220, 53, 69, 0.25) !important;
  border-left: 4px solid var(--week-header-assessment) !important;
}

[data-theme="dark"] .week-row.row-break, [data-theme="dark"] tr.week-row.row-break {
  background-color: rgba(232, 62, 140, 0.25) !important;
  border-left: 4px solid var(--week-header-break) !important;
}

select:focus {
  outline: none;
  border-color: var(--input-focus);
  box-shadow: 0 0 0 3px var(--input-focus-shadow);
}

.form-row {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  margin-bottom: 15px;
}

.form-row > div {
  flex: 1;
  min-width: 150px;
}

/* WCAG 2.1 AA compliant button styles */
button {
  margin: 10px 5px;
  padding: 12px 24px;
  border: none;
  border-radius: 8px;
  background: var(--button-primary);
  color: white;
  cursor: pointer;
  font-size: 16px; /* Minimum readable font size */
  font-weight: 500;
  transition: background 0.2s ease, transform 0.1s ease;
  min-height: 44px; /* Minimum touch target size */
  min-width: 44px; /* Minimum touch target size */
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  line-height: 1.5;
}

button:hover {
  background: var(--button-primary-hover);
  transform: translateY(-1px);
}

button:focus {
  background: var(--button-primary-hover);
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
  transform: translateY(-1px);
}

button:active {
  transform: translateY(0);
}

/* Preset Button Styles (from timetable/generate.html) */
.preset-container {
  display: flex;
  gap: 16px;
  margin: 20px 0;
  justify-content: center;
  flex-wrap: wrap;
}
.preset-btn {
  position: relative;
  padding: 16px 24px;
  border: 2px solid var(--border-color);
  border-radius: 8px;
  background: var(--card-bg);
  color: var(--text-primary);
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  min-width: 160px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  height: 85px;
  justify-content: flex-start;
  overflow: hidden;
}
.preset-btn:hover {
  background: var(--button-primary);
  color: white;
  border-color: var(--button-primary);
  transform: translateY(-2px);
}
.preset-btn:active {
  transform: translateY(0);
}

.module-code {
  position: absolute;
  bottom: 10px;
  left: 12px;
  background-color: #6c757d;
  color: #fff;
  padding: 2px 8px;
  font-size: 0.75rem;
  border-radius: 12px;
  font-weight: 500;
}

.year-tag {
  position: absolute;
  bottom: 10px;
  right: 12px;
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 600;
  color: white;
}

.year-1 {
  background-color: #007bff;
}

.year-2 {
  background-color: #28a745;
}

.year-3 {
  background-color: #fd7e14;
}



.reset-btn {
  background: var(--button-secondary);
  color: white;
  text-align: center;
  padding: 10px 20px !important;
  border: none;
  border-radius: 6px;
  font-size: 0.9rem;
  margin: 0 5px !important;
  cursor: pointer;
  box-shadow: 0 2px 4px var(--shadow-color);
  transition: background 0.3s ease;
  min-width: 80px;
}

.reset-btn:hover {
  background: var(--button-secondary-hover);
}

.week-block {
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: var(--bg-secondary);
  margin-bottom: 20px;
  overflow: hidden;
  box-shadow: 0 2px 6px var(--shadow-color-light);
}

.week-header {
  padding: 15px 20px;
  background: #7e7e7e;
  color: white;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-weight: 600;
}

.week-content {
  display: none;
  padding: 20px;
  background: var(--bg-primary);
}

.week-block.open .week-content {
  display: block;
}

.week-summary {
  font-size: 0.9rem;
  font-weight: 400;
}

#output {
  white-space: pre-wrap;
  background: var(--bg-secondary);
  padding: 12px;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  margin-top: 30px;
  color: var(--text-primary);
}

#toast {
  position: fixed;
  bottom: 30px;
  right: 30px;
  padding: 12px 20px;
  border-radius: 8px;
  font-size: 14px;
  color: white;
  z-index: 9999;
  opacity: 0;
  display: none;
  transition: opacity 0.5s ease-in-out;
  background-color: var(--toast-bg);
}

#toast.show {
  display: block;
  opacity: 1;
}

.toast-success { 
  background-color: #28a745; 
}
.toast-info    { 
  background-color: #007bff; 
}
.toast-error   { 
  background-color: #dc3545; 
}
.toast-warning { 
  background-color: #ffc107; color: #000; 
}

.modal-overlay {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: var(--modal-overlay);
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 9999;
}

.modal-box {
  background: var(--modal-bg);
  padding: 24px 32px;
  border-radius: 10px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.2);
  text-align: center;
  max-width: 360px;
}

.modal-box h3 {
  margin-top: 0;
  font-size: 1.3rem;
  color: var(--text-primary);
}

.modal-box p {
  font-size: 0.95rem;
  margin: 10px 0 20px;
  color: var(--text-secondary);
}

.modal-actions {
  display: flex;
  justify-content: space-between;
  gap: 12px;
}

.cancel-btn,
.confirm-btn {
  padding: 8px 16px;
  border: none;
  border-radius: 6px;
  font-size: 0.95rem;
  cursor: pointer;
}

.cancel-btn {
  background: var(--border-color);
  color: var(--text-primary);
}

.cancel-btn:hover {
  background: var(--text-muted);
}

.confirm-btn {
  background: var(--button-secondary);
  color: white;
}

.confirm-btn:hover {
  background: var(--button-secondary-hover);
}

button:disabled {
  background-color: var(--text-muted);
  cursor: not-allowed;
  opacity: 0.6;
}

/* Modern container for preset editor */
.container {
  max-width: 950px;
  margin: 32px auto 32px auto;
  padding: 32px 24px 24px 24px;
  background: var(--bg-secondary);
  border-radius: 16px;
  box-shadow: 0 4px 24px var(--shadow-color);
  border: 1px solid var(--border-color);
}

/* Modern table styles */
#weekTable {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  background: var(--bg-secondary);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 2px 8px var(--shadow-color-light);
  margin-bottom: 24px;

}
#weekTable th, #weekTable td {
  padding: 10px 8px;
  text-align: left;
}
#weekTable th {
  background: var(--navbar-bg);
  color: #fff;
  font-weight: 600;
  font-size: 1rem;
  border-bottom: 2px solid var(--border-color);
}
#weekTable tr {
  background: var(--bg-secondary);
  transition: background 0.2s;
}
#weekTable tr:nth-child(even) {
  background: var(--bg-primary);
}
#weekTable td {
  border-bottom: 1px solid var(--border-color);
}
#weekTable tr:last-child td {
  border-bottom: none;
}
#weekTable input, #weekTable select {
  width: 100%;
  min-width: 60px;
  margin-bottom: 0;
  font-size: 0.97rem;
  padding: 6px 8px;
}

/* Add week button spacing */
.container > button[type="button"] {
  display: block;
  margin: 0 auto 0 0;
  margin-bottom: 0;
  margin-top: 8px;
}

/* Modernize h1 and h2 */
.container h1 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 18px;
  color: var(--text-primary);
  letter-spacing: -1px;
}
.container h2 {
  font-size: 1.2rem;
  font-weight: 600;
  margin-top: 32px;
  margin-bottom: 12px;
  color: var(--text-secondary);
  letter-spacing: -0.5px;
}

/* Responsive for mobile */
@media (max-width: 700px) {
  .container {
    padding: 16px 4px 16px 4px;
  }
  #weekTable th, #weekTable td {
    padding: 6px 2px;
    font-size: 0.95rem;
  }
  .container h1 {
    font-size: 1.3rem;
  }
  .container h2 {
    font-size: 1rem;
  }
}

@media (max-width: 600px) {
  .preset-btns { flex-direction: column; align-items: stretch; }
  
  .sticky-footer {
    padding: 8px 10px;
    gap: 8px;
  }
  
  .sticky-footer button {
    font-size: 0.85rem;
    padding: 8px 12px !important;
    min-width: auto;
  }
  
  .reset-btn {
    min-width: 70px !important;
    font-size: 0.8rem;
  }
}

@media (max-width: 800px) {
  .sticky-footer {
    padding: 10px 15px;
    gap: 8px;
  }
  
  .sticky-footer button {
    font-size: 0.9rem;
    padding: 8px 14px !important;
  }
  
  .reset-btn {
    min-width: 75px !important;
  }
}

.sticky-footer {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  background: var(--navbar-bg);
  padding: 12px 20px;
  box-shadow: 0 -2px 8px var(--shadow-color);
  text-align: center;
  z-index: 1000;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.add-preset-btn {
  padding: 10px 24px;
  font-size: 1rem;
  background: #28a745;
  color: white;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-weight: bold;
  transition: background 0.3s ease;
}

.add-preset-btn:hover {
  background: #218838;
}

.compact-tutor input,
.compact-tutor select {
  margin-right: 8px;
  flex: 1;
  min-width: 0;
}

.compact-tutor {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}

.module-details {
  background: var(--bg-secondary);
  padding: 20px;
  border-radius: 12px;
  margin: 20px auto;
  max-width: 800px;
  box-shadow: 0 2px 6px var(--shadow-color-light);
  border: 1px solid var(--border-color);
}
.module-details h2 {
  margin-top: 0;
  color: var(--text-primary);
}
.module-details ul {
  padding-left: 20px;
  margin-top: 5px;
}

#moduleDetails {
  display: none;
}

#previewFrame {
  display: none;
}

/* Modern dropdown styles */
.dropdown {
  position: relative;
  display: inline-block;
}

.dropdown-btn {
  background: var(--navbar-bg);
  border: none;
  color: white;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  padding: 10px 18px 10px 14px;
  border-radius: 8px;
  transition: all 0.2s cubic-bezier(.4,0,.2,1);
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  min-width: 44px;
  white-space: nowrap;
  box-shadow: 0 2px 8px rgba(0,0,0,0.07);
  position: relative;
}
.dropdown-btn::after {
  content: '\25BC'; /* Downward chevron */
  font-size: 0.8em;
  margin-left: 8px;
  opacity: 0.7;
  transition: transform 0.2s;
  color: #fff;
}
.dropdown-btn:hover::after,
.dropdown-btn:focus::after {
  transform: translateY(2px) scale(1.1);
  opacity: 1;
}
.dropdown-btn:hover,
.dropdown-btn:focus {
  background-color: var(--navbar-bg);
  color: #fff;
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}
[data-theme="dark"] .dropdown-btn {
  color: #fff;
  background: var(--navbar-bg);
  box-shadow: 0 2px 8px rgba(0,0,0,0.18);
}
[data-theme="dark"] .dropdown-btn:hover,
[data-theme="dark"] .dropdown-btn:focus {
  background-color: var(--navbar-bg);
  color: #fff;
  box-shadow: 0 4px 16px rgba(0,0,0,0.22);
}

.dropdown-content {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  background: #ffffff;
  width: max-content;
  min-width: 180px;
  box-shadow: 0 8px 24px var(--shadow-color);
  border-radius: 8px;
  border: 1px solid var(--border-color);
  z-index: 1001;
  overflow: hidden;
  margin-top: 4px;
  backdrop-filter: blur(10px);
}

.dropdown:hover .dropdown-content {
  display: block;
  animation: dropdownFadeIn 0.2s ease-out;
}

@keyframes dropdownFadeIn {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.dropdown-content a {
  color: #1a1a1a !important;
  padding: 10px 14px;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 8px;
  transition: all 0.2s ease;
  border-bottom: 1px solid var(--border-color);
  white-space: nowrap;
  line-height: 1.4;
  min-height: 40px;
  font-size: 0.9rem;
  font-weight: 500;
}

.dropdown-content a:last-child {
  border-bottom: none;
}

.dropdown-content a:hover {
  background-color: rgba(0, 0, 0, 0.05);
  color: #1a1a1a !important;
  transform: translateX(2px);
}

.dropdown-content a:focus {
  background-color: rgba(0, 0, 0, 0.05);
  color: #1a1a1a !important;
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}

[data-theme="dark"] .dropdown-content {
  background: #2d2d2d;
  border-color: var(--border-color);
}

[data-theme="dark"] .dropdown-content a {
  color: #ffffff !important;
}

[data-theme="dark"] .dropdown-content a:hover {
  background-color: rgba(255, 255, 255, 0.1);
  color: #ffffff !important;
}

[data-theme="dark"] .dropdown-content a:focus {
  background-color: rgba(255, 255, 255, 0.1);
  color: #ffffff !important;
}

/* Responsive dropdown */
@media (max-width: 888px) {
  .dropdown-btn {
    font-size: 0.85rem;
    padding: 6px 10px;
    gap: 4px;
  }
  
  .dropdown-content {
    min-width: 160px;
    margin-top: 2px;
  }
  
  .dropdown-content a {
    padding: 8px 12px;
    font-size: 0.85rem;
    gap: 6px;
  }
}

@media (max-width: 640px) {
  .dropdown-btn {
    font-size: 0.8rem;
    padding: 5px 8px;
    gap: 3px;
  }
  
  .dropdown-content {
    min-width: 140px;
  }
  
  .dropdown-content a {
    padding: 7px 10px;
    font-size: 0.8rem;
    gap: 5px;
  }
}

@media (max-width: 480px) {
  .dropdown-btn {
    font-size: 0.75rem;
    padding: 4px 6px;
    gap: 2px;
  }
  
  .dropdown-content {
    min-width: 120px;
  }
  
  .dropdown-content a {
    padding: 6px 8px;
    font-size: 0.75rem;
    gap: 4px;
  }
}

#weekTable td .week-number {
  display: block;
  text-align: center;
  font-weight: 600;
  font-size: 1.05em;
}

#weekTable td:first-child {
  text-align: center;
  vertical-align: middle;
}

.week-row.row-highlighted, tr.week-row.row-highlighted {
  border: 2.5px solid #FFD600 !important;
  border-radius: 7px;
  box-shadow: none !important;
  z-index: 2;
}
[data-theme="dark"] .week-row.row-highlighted, [data-theme="dark"] tr.week-row.row-highlighted {
  border: 2.5px solid #FFEB3B !important;
}

#weekTable tr.week-row {
  outline: 2.5px solid transparent;
  outline-offset: -2.5px;
  box-sizing: border-box;
}

#weekTable tr.week-row td {
  box-sizing: border-box;
}

/* Darker background for highlighted rows based on week type */
.week-row.row-teaching.row-highlighted {
  background-color: rgba(0, 64, 128, 0.35) !important;
}

.week-row.row-reading.row-highlighted {
  background-color: rgba(240, 173, 78, 0.35) !important;
}

.week-row.row-assessment.row-highlighted {
  background-color: rgba(220, 53, 69, 0.35) !important;
}

.week-row.row-break.row-highlighted {
  background-color: rgba(189, 97, 217, 0.35) !important;
}

[data-theme="dark"] .week-row.row-teaching.row-highlighted {
  background-color: rgba(0, 115, 230, 0.45) !important;
}

[data-theme="dark"] .week-row.row-reading.row-highlighted {
  background-color: rgba(255, 193, 7, 0.45) !important;
}

[data-theme="dark"] .week-row.row-assessment.row-highlighted {
  background-color: rgba(220, 53, 69, 0.45) !important;
}

[data-theme="dark"] .week-row.row-break.row-highlighted {
  background-color: rgba(232, 62, 140, 0.45) !important;
}

input.valid, textarea.valid, select.valid {
  border-color: #28a745 !important;
  box-shadow: 0 0 0 2px rgba(40,167,69,0.15);
}
input.invalid, textarea.invalid, select.invalid {
  border-color: #dc3545 !important;
  box-shadow: 0 0 0 2px rgba(220,53,69,0.15);
}

[data-theme="dark"] input.valid, [data-theme="dark"] textarea.valid, [data-theme="dark"] select.valid {
  border-color: #27ae60 !important;
}
[data-theme="dark"] input.invalid, [data-theme="dark"] textarea.invalid, [data-theme="dark"] select.invalid {
  border-color: #e74c3c !important;
}

.navbar-dropdown-btn {
  background: var(--navbar-bg) !important;
  color: #fff !important;
  font-weight: 700;
  border: none;
  box-shadow: none;
  padding: 10px 18px 10px 14px;
  border-radius: 8px;
  min-height: 44px;
  min-width: 44px;
  display: flex;
  align-items: center;
  gap: 8px;
  position: relative;
}
.navbar-dropdown-btn::after {
  color: #fff !important;
}
.navbar-dropdown-btn:hover,
.navbar-dropdown-btn:focus {
  background: var(--navbar-bg) !important;
  color: #fff !important;
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
  outline: var(--focus-outline);
  outline-offset: var(--focus-outline-offset);
}
[data-theme="dark"] .navbar-dropdown-btn {
  background: var(--navbar-bg) !important;
  color: #fff !important;
}
[data-theme="dark"] .navbar-dropdown-btn:hover,
[data-theme="dark"] .navbar-dropdown-btn:focus {
  background: var(--navbar-bg) !important;
  color: #fff !important;
}