:root {
  --color-primary: #1a73e8;
  --color-primary-dark: #1557b0;
  --color-primary-light: #4285f4;
  --color-secondary: #5f6368;
  --color-secondary-dark: #3c4043;
  --color-success: #1e8e3e;
  --color-success-light: #e6f4ea;
  --color-error: #d93025;
  --color-error-light: #fce8e6;
  --color-warning: #f9ab00;
  --color-bg: #f8f9fa;
  --color-bg-white: #ffffff;
  --color-text-primary: #202124;
  --color-text-secondary: #5f6368;
  --color-text-tertiary: #80868b;
  --color-border: #dadce0;
  --color-border-light: #f1f3f4;
  --shadow-sm: 0 1px 2px 0 rgba(60,64,67,0.3), 0 1px 3px 1px rgba(60,64,67,0.15);
  --shadow-md: 0 1px 3px 0 rgba(60,64,67,0.3), 0 4px 8px 3px rgba(60,64,67,0.15);
  --shadow-lg: 0 2px 6px 2px rgba(60,64,67,0.15), 0 8px 24px 4px rgba(60,64,67,0.15);
  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --font-family-base: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, 'Noto Sans', sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 2rem;
  --font-size-4xl: 2.5rem;
  --line-height-tight: 1.25;
  --line-height-base: 1.5;
  --line-height-relaxed: 1.75;
  --letter-spacing-normal: 0;
  --letter-spacing-wide: 0.01em;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-base);
  line-height: var(--line-height-base);
  color: var(--color-text-primary);
  background-color: var(--color-bg);
  letter-spacing: var(--letter-spacing-normal);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.content {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1.5rem;
  background-color: var(--color-bg);
  position: relative;
  z-index: 1;
}

.navbar {
  background-color: var(--color-bg-white);
  color: var(--color-text-primary);
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 0.75rem 0;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-base);
}

.navbar:hover {
  box-shadow: var(--shadow-md);
}

.navbar-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 1.5rem;
}

.navbar-logo {
  font-size: var(--font-size-xl);
  font-weight: 700;
  text-decoration: none;
  color: var(--color-primary);
  transition: color var(--transition-fast);
  letter-spacing: var(--letter-spacing-wide);
}

.navbar-logo:hover,
.navbar-logo:focus-visible {
  color: var(--color-primary-dark);
  outline: none;
}

.navbar-links {
  display: flex;
  list-style: none;
  gap: 0.5rem;
}

.navbar-links li {
  margin: 0;
}

.navbar-links a {
  color: var(--color-text-secondary);
  text-decoration: none;
  padding: 0.5rem 1rem;
  border-radius: var(--radius-md);
  font-weight: 500;
  font-size: var(--font-size-sm);
  transition: all var(--transition-fast);
  position: relative;
}

.navbar-links a:hover {
  color: var(--color-primary);
  background-color: rgba(26, 115, 232, 0.08);
}

.navbar-links a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.navbar-links a:active {
  transform: scale(0.98);
  background-color: rgba(26, 115, 232, 0.12);
}

.top-video {
  width: 100%;
  position: relative;
  overflow: hidden;
  height: 75vh;
  min-height: 500px;
  margin-top: 56px;
}

.top-video video {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.carousel {
  margin-top: 70px;
  position: relative;
  width: 35%;
  height: 389px;
  overflow: hidden;
  background-color: rgba(0, 0, 0, 0.3);
  z-index: 2;
  margin-left: 50px;
}

.course-center .carousel {
  width: 100%;
  max-width: 1200px;
  aspect-ratio: 16/9;
  margin: 70px auto 1.5rem;
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  background-color: transparent;
  box-shadow: var(--shadow-md);
}

.course-center .carousel-inner {
  display: flex;
  transition: transform var(--transition-base);
  height: 100%;
}

.course-center .carousel-item {
  min-width: 100%;
  height: 100%;
  position: relative;
  cursor: pointer;
  transition: all var(--transition-base);
}

.course-center .carousel-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.course-center .carousel-caption {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: linear-gradient(to top, rgba(0,0,0,0.85) 0%, rgba(0,0,0,0.4) 50%, transparent 100%);
  color: white;
  padding: 2.5rem 2rem 1.5rem;
  text-align: left;
}

.course-center .carousel-caption h3 {
  font-size: var(--font-size-2xl);
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.course-center .carousel-caption p {
  font-size: var(--font-size-base);
  opacity: 0.95;
  line-height: var(--line-height-relaxed);
}

.course-center .carousel-control-prev,
.course-center .carousel-control-next {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(255, 255, 255, 0.95);
  border: none;
  border-radius: var(--radius-full);
  width: 48px;
  height: 48px;
  font-size: 1.25rem;
  cursor: pointer;
  z-index: 10;
  color: var(--color-text-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-fast);
}

.course-center .carousel-control-prev:hover,
.course-center .carousel-control-next:hover {
  background: white;
  transform: translateY(-50%) scale(1.05);
  box-shadow: var(--shadow-lg);
}

.course-center .carousel-control-prev:active,
.course-center .carousel-control-next:active {
  transform: translateY(-50%) scale(0.95);
}

.course-center .carousel-control-prev:focus-visible,
.course-center .carousel-control-next:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.course-center .carousel-control-prev {
  left: 1.25rem;
}

.course-center .carousel-control-next {
  right: 1.25rem;
}

.school-name {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(calc(-50% - 350px), -50%);
  text-align: center;
  color: white;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.8), 0 4px 16px rgba(0, 0, 0, 0.4);
  padding: 3rem 2rem;
  max-width: 900px;
  width: 90%;
  z-index: 2;
  animation: fadeInUp 0.8s ease-out;
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translate(calc(-50% - 350px), calc(-50% + 30px));
  }
  to {
    opacity: 1;
    transform: translate(calc(-50% - 350px), -50%);
  }
}

.school-name h1 {
  font-size: var(--font-size-4xl);
  margin-bottom: 1.5rem;
  line-height: var(--line-height-tight);
  font-weight: 700;
  letter-spacing: var(--letter-spacing-wide);
}

.school-name h2 {
  font-size: var(--font-size-2xl);
  margin-bottom: 0;
  font-weight: 400;
  opacity: 0.95;
}

.site-collection-carousel {
  width: 100%;
  max-width: 1200px;
  margin: 70px auto 0;
  aspect-ratio: 16/9;
}

.carousel-container {
  display: flex;
  transition: transform var(--transition-base);
  height: 100%;
}

.carousel-item {
  flex: 0 0 100%;
  height: 100%;
  position: relative;
}

.carousel-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  cursor: pointer;
  transition: transform var(--transition-slow);
}

.carousel-item:hover img {
  transform: scale(1.02);
}

.carousel-item .site-favicon {
  object-fit: contain;
  background-color: rgba(255, 255, 255, 0.95);
  padding: 2.5rem;
}

.carousel-controls {
  position: absolute;
  top: 50%;
  left: 0;
  right: 0;
  transform: translateY(-50%);
  display: flex;
  justify-content: space-between;
  padding: 0 1.25rem;
}

.carousel-control {
  background-color: rgba(0, 0, 0, 0.6);
  color: white;
  border: none;
  padding: 0.75rem;
  border-radius: var(--radius-full);
  cursor: pointer;
  font-size: 1.25rem;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
}

.carousel-control:hover {
  background-color: rgba(0, 0, 0, 0.8);
  transform: scale(1.05);
}

.carousel-control:focus-visible {
  outline: 2px solid white;
  outline-offset: 2px;
}

.carousel-control:active {
  transform: scale(0.95);
}

.carousel-indicators {
  position: absolute;
  bottom: 1.25rem;
  left: 0;
  right: 0;
  display: flex;
  justify-content: center;
  gap: 0.5rem;
}

.carousel-indicator {
  width: 10px;
  height: 10px;
  border-radius: var(--radius-full);
  background-color: rgba(255, 255, 255, 0.5);
  margin: 0;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: 2px solid transparent;
}

.carousel-indicator:hover {
  background-color: rgba(255, 255, 255, 0.8);
  transform: scale(1.1);
}

.carousel-indicator.active {
  background-color: white;
  transform: scale(1.2);
}

.carousel-indicator:focus-visible {
  outline: 2px solid white;
  outline-offset: 2px;
}

.content {
  max-width: 1200px;
  margin: 1.5rem auto;
  padding: 0 1.5rem;
}

.course-content {
  max-width: 1200px;
  margin: 150px auto 1.5rem;
  padding: 0 1.5rem;
}

.link-list {
  background-color: var(--color-bg-white);
  padding: 1.5rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  margin-top: 1.5rem;
}

.link-list h2 {
  margin-bottom: 1rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-xl);
  font-weight: 600;
}

.link-list ul {
  list-style: none;
}

.link-list li {
  margin-bottom: 0.5rem;
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--color-border-light);
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast);
}

.link-list li:hover {
  background-color: var(--color-bg);
}

.link-list li:last-child {
  border-bottom: none;
}

.link-list a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition-fast);
}

.link-list a:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

.tool-site-container {
  display: flex;
  gap: 1.5rem;
  margin-top: 2rem;
}

.tool-section {
  flex: 1;
  background-color: var(--color-bg-white);
  padding: 2rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  text-align: center;
  transition: all var(--transition-base);
}

.tool-section:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.tool-section h2 {
  margin-bottom: 1.25rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-xl);
  font-weight: 600;
}

.tool-card {
  background-color: rgba(26, 115, 232, 0.08);
  border: 2px solid var(--color-primary);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  cursor: pointer;
  transition: all var(--transition-base);
}

.tool-card:hover {
  background-color: rgba(26, 115, 232, 0.12);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.tool-card:active {
  transform: translateY(-2px);
}

.tool-card:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

.tool-card h3 {
  margin-bottom: 0.5rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-lg);
  font-weight: 600;
}

.tool-card p {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
}

.site-section {
  flex: 1;
  background-color: var(--color-bg-white);
  padding: 2rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  text-align: center;
  transition: all var(--transition-base);
}

.site-section:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.site-section h2 {
  margin-bottom: 1.25rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-xl);
  font-weight: 600;
}

.site-card {
  background-color: var(--color-bg);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  cursor: pointer;
  transition: all var(--transition-base);
}

.site-card:hover {
  background-color: var(--color-border-light);
  border-color: var(--color-secondary);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.site-card:active {
  transform: translateY(-2px);
}

.site-card:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

.site-card h3 {
  margin-bottom: 0.5rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-lg);
  font-weight: 600;
}

.site-card p {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
}

.site-grid {
  background-color: var(--color-bg-white);
  padding: 2rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  margin-top: 2rem;
}

.site-grid h2 {
  margin-bottom: 1.5rem;
  color: var(--color-text-primary);
  text-align: center;
  font-size: var(--font-size-2xl);
  font-weight: 600;
}

.grid-container {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.5rem;
  padding: 0 0.5rem;
}

.grid-item {
  display: flex;
  justify-content: center;
}

.site-card {
  background-color: var(--color-bg-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  width: 100%;
  transition: all var(--transition-base);
}

.site-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-primary);
}

.site-image {
  height: 160px;
  overflow: hidden;
  position: relative;
}

.site-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.site-card:hover .site-image img {
  transform: scale(1.05);
}

.site-favicon {
  object-fit: contain;
  background-color: var(--color-bg-white);
  padding: 1.25rem;
}

.site-info {
  padding: 1rem;
  text-align: center;
}

.site-info a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 600;
  display: block;
  margin-bottom: 0.5rem;
  font-size: var(--font-size-base);
  transition: color var(--transition-fast);
}

.site-info a:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

.site-info p {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  margin: 0;
  line-height: var(--line-height-relaxed);
}

.tool-grid {
  background-color: var(--color-bg-white);
  padding: 2rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  margin-top: 2rem;
}

.tool-grid h2 {
  margin-bottom: 1.5rem;
  color: var(--color-text-primary);
  text-align: center;
  font-size: var(--font-size-2xl);
  font-weight: 600;
}

.tool-card {
  background-color: var(--color-bg-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  width: 100%;
  transition: all var(--transition-base);
}

.tool-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-primary);
}

.tool-image {
  height: 160px;
  overflow: hidden;
}

.tool-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.tool-card:hover .tool-image img {
  transform: scale(1.05);
}

.tool-info {
  padding: 1rem;
  text-align: center;
}

.tool-info a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 600;
  display: block;
  margin-bottom: 0.5rem;
  font-size: var(--font-size-base);
  transition: color var(--transition-fast);
}

.tool-info a:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

.tool-info p {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  margin: 0;
  line-height: var(--line-height-relaxed);
}

.form-container {
  max-width: 520px;
  margin: 6.25rem auto 3rem;
  background-color: var(--color-bg-white);
  padding: 2.5rem;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  animation: slideUp 0.4s ease-out;
}

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

.form-container h2 {
  margin-bottom: 1.5rem;
  text-align: center;
  color: var(--color-text-primary);
  font-size: var(--font-size-2xl);
  font-weight: 600;
}

.form-group {
  margin-bottom: 1.5rem;
}

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

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 2px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--font-size-base);
  font-family: var(--font-family-base);
  transition: all var(--transition-fast);
  background-color: var(--color-bg-white);
}

.form-group input:hover,
.form-group textarea:hover {
  border-color: var(--color-secondary);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.15);
}

.form-group textarea {
  height: 150px;
  resize: vertical;
  line-height: var(--line-height-relaxed);
}

.form-buttons {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 2rem;
}

.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-size-base);
  font-weight: 500;
  transition: all var(--transition-fast);
  font-family: var(--font-family-base);
  flex: 1;
}

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

.btn-primary:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

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

.btn-primary:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

.btn-secondary {
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  border: 2px solid var(--color-border);
}

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

.btn-secondary:active {
  transform: translateY(1px);
}

.btn-secondary:focus-visible {
  outline: 3px solid var(--color-secondary);
  outline-offset: 2px;
}

.footer {
  background-color: var(--color-text-primary);
  color: white;
  text-align: center;
  padding: 2rem;
  margin-top: 3rem;
}

.footer a {
  color: #8ab4f8;
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition-fast);
}

.footer a:hover {
  color: #aecbfa;
  text-decoration: underline;
}

.footer p {
  margin-bottom: 0.5rem;
  font-size: var(--font-size-sm);
  opacity: 0.9;
}

.footer p:last-child {
  margin-bottom: 0;
}

.message {
  position: fixed;
  top: 80px;
  left: 50%;
  transform: translateX(-50%);
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  text-align: center;
  font-weight: 500;
  animation: messageIn 0.3s ease-out;
  z-index: 9999;
  box-shadow: var(--shadow-lg);
  min-width: 300px;
}

@keyframes messageIn {
  from {
    opacity: 0;
    top: 70px;
  }
  to {
    opacity: 1;
    top: 80px;
  }
}

.message.success {
  background-color: var(--color-success-light);
  color: var(--color-success);
  border: 1px solid rgba(30, 142, 62, 0.3);
}

.message.error {
  background-color: var(--color-error-light);
  color: var(--color-error);
  border: 1px solid rgba(217, 48, 37, 0.3);
}

.toggle-buttons {
  display: flex;
  justify-content: center;
  margin-bottom: 1.5rem;
  background-color: var(--color-bg);
  padding: 0.25rem;
  border-radius: var(--radius-md);
}

.toggle-btn {
  padding: 0.625rem 1.25rem;
  border: none;
  background-color: transparent;
  cursor: pointer;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  font-family: var(--font-family-base);
  flex: 1;
}

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

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

.toggle-btn:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.tab-content {
  display: none;
  animation: fadeIn 0.25s ease-out;
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.tab-content.active {
  display: block;
}

.search-container {
  background-color: var(--color-bg-white);
  padding: 2.5rem 1.5rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
  position: relative;
  z-index: 1;
}

.search-box {
  max-width: 720px;
  margin: 0 auto;
  display: flex;
  justify-content: center;
}

.search-box input {
  width: 100%;
  padding: 1rem 1.25rem;
  font-size: var(--font-size-base);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-md) 0 0 var(--radius-md);
  outline: none;
  transition: all var(--transition-fast);
  font-family: var(--font-family-base);
}

.search-box input:hover {
  border-color: var(--color-secondary);
}

.search-box input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.15);
}

.search-btn {
  padding: 1rem 2rem;
  background-color: var(--color-primary);
  color: white;
  border: none;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-size: var(--font-size-base);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-family-base);
  white-space: nowrap;
}

.search-btn:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

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

.search-btn:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

.data-panel {
  background-color: var(--color-bg-white);
  padding: 2.5rem 1.5rem;
  margin: 1.5rem auto;
  max-width: 1200px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

.data-panel h3 {
  text-align: center;
  margin-bottom: 2rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-2xl);
  font-weight: 600;
}

.data-cards {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  overflow-x: auto;
  padding-bottom: 1rem;
  flex-wrap: nowrap;
}

.data-card {
  background: linear-gradient(135deg, var(--color-bg-white) 0%, var(--color-bg) 100%);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  text-align: center;
  min-width: 150px;
  flex: 1;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
  max-width: none;
}

.data-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-light));
  opacity: 0;
  transition: opacity var(--transition-base);
}

.data-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-primary);
}

.data-card:hover::before {
  opacity: 1;
}

.data-card h4 {
  color: var(--color-text-secondary);
  margin-bottom: 0.5rem;
  font-size: var(--font-size-xs);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.data-card p {
  color: var(--color-primary);
  font-size: var(--font-size-2xl);
  font-weight: 700;
  margin: 0;
  line-height: var(--line-height-tight);
}

.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 1.75rem;
  padding: 1.25rem 0;
}

.course-card {
  background-color: var(--color-bg-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-base);
  display: flex;
  flex-direction: column;
}

.course-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-primary);
}

.course-image {
  height: 200px;
  overflow: hidden;
  position: relative;
}

.course-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.course-card:hover .course-image img {
  transform: scale(1.08);
}

.course-info {
  padding: 1.25rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.course-info h3 {
  margin-bottom: 0.5rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-lg);
  font-weight: 600;
  line-height: var(--line-height-tight);
}

.course-info h4 {
  margin-bottom: 0.5rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-base);
  font-weight: 600;
}

.course-info p {
  margin-bottom: 1rem;
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  line-height: var(--line-height-relaxed);
  flex: 1;
}

.course-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1rem;
  font-size: var(--font-size-xs);
  color: var(--color-text-tertiary);
}

.course-meta span {
  background-color: var(--color-bg);
  padding: 0.25rem 0.625rem;
  border-radius: var(--radius-sm);
  font-weight: 500;
}

.course-actions {
  display: flex;
  gap: 0.75rem;
}

.action-btn {
  flex: 1;
  padding: 0.75rem;
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-family-base);
}

.action-btn.play {
  background-color: var(--color-primary);
  color: white;
}

.action-btn.play:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.action-btn.play:active {
  transform: translateY(0);
}

.action-btn.play:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}



.more-btn {
  background-color: var(--color-primary);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  padding: 0.875rem 2rem;
  font-size: var(--font-size-base);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-family-base);
  margin-top: 1rem;
}

.more-btn:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

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

.more-btn:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}



.related-courses {
  margin-top: 2rem;
}

.related-courses h3 {
  color: var(--color-text-primary);
  margin-bottom: 1.5rem;
  font-size: var(--font-size-xl);
  font-weight: 600;
}

.profile-container {
  display: flex;
  gap: 2rem;
  margin-top: 6rem;
  flex-wrap: wrap;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
}

.profile-sidebar {
  width: 250px;
  background-color: var(--color-bg-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  box-shadow: var(--shadow-sm);
  min-height: 350px;
  position: sticky;
  top: 88px;
  word-wrap: break-word;
  text-align: center;
  transition: all var(--transition-base);
}

.profile-sidebar:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.profile-content {
  flex: 1;
  min-width: 400px;
  background-color: var(--color-bg-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
}

.profile-content:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

/* 响应式设计 */
@media (max-width: 1024px) {
  .profile-container {
    flex-direction: column;
    align-items: center;
  }
  
  .profile-sidebar {
    width: 100%;
    max-width: 600px;
    position: relative;
    top: 0;
  }
  
  .profile-content {
    width: 100%;
    min-width: auto;
  }
  
  .profile-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
  }
  
  .profile-nav li {
    margin-bottom: 0;
  }
  
  .profile-nav a {
    padding: 0.5rem 1rem;
    white-space: nowrap;
  }
}

@media (max-width: 768px) {
  .profile-container {
    gap: 2rem;
    margin-top: 6rem;
    padding: 0 1rem;
  }
  
  .profile-sidebar {
    padding: 1.5rem;
  }
  
  .profile-content {
    padding: 1.5rem;
  }
  
  .profile-nav {
    gap: 0.25rem;
  }
  
  .profile-nav a {
    padding: 0.4rem 0.8rem;
    font-size: var(--font-size-xs);
  }
}

.user-info {
  text-align: center;
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--color-border-light);
}

.avatar {
  width: 120px;
  height: 120px;
  border-radius: var(--radius-full);
  overflow: hidden;
  margin: 0 auto 1.5rem;
  border: 4px solid var(--color-border-light);
  transition: all var(--transition-base);
  box-shadow: var(--shadow-sm);
}

.avatar:hover {
  border-color: var(--color-primary);
  transform: scale(1.05);
  box-shadow: var(--shadow-md);
}

.avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.user-info h3 {
  margin-bottom: 0.75rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-xl);
  font-weight: 600;
  line-height: var(--line-height-tight);
}

.user-info p {
  color: var(--color-text-secondary);
  font-size: var(--font-size-base);
  margin-bottom: 1.5rem;
  line-height: var(--line-height-base);
}

.user-info p a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 500;
  font-size: var(--font-size-base);
  transition: color var(--transition-fast);
}

.user-info p a:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

.logout-btn {
  margin-top: 1.5rem;
  padding: 0.875rem 2rem;
  background-color: var(--color-error);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--font-size-base);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-family-base);
  width: 100%;
  max-width: 220px;
  margin-left: auto;
  margin-right: auto;
  box-shadow: var(--shadow-sm);
}

.logout-btn:hover {
  background-color: #c1271e;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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

.logout-btn:focus-visible {
  outline: 3px solid var(--color-error);
  outline-offset: 2px;
}

.profile-nav {
  list-style: none;
  margin-top: 1rem;
}

.profile-nav li {
  margin-bottom: 0.5rem;
}

.profile-nav a {
  display: block;
  padding: 0.75rem 1rem;
  color: var(--color-text-secondary);
  text-decoration: none;
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  font-weight: 500;
  font-size: var(--font-size-sm);
  text-align: center;
}

.profile-nav a:hover {
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  transform: translateX(4px);
}

.profile-nav a.active {
  background-color: rgba(26, 115, 232, 0.12);
  color: var(--color-primary);
  font-weight: 600;
  box-shadow: var(--shadow-sm);
}

.profile-nav a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.profile-content {
  flex: 1;
  background-color: var(--color-bg-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-sm);
}

.content-section {
  display: none;
}

.content-section.active {
  display: block;
}

.settings-form {
  max-width: 600px;
}

.form-group {
  margin-bottom: 1.5rem;
}

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

.form-group input {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  transition: border-color var(--transition-fast);
}

.form-group input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.1);
}

.save-btn {
  padding: 0.75rem 1.5rem;
  background-color: var(--color-primary);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

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

.favorites-list, .history-list {
  margin-top: 1rem;
}

.favorite-item, .history-item {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  padding: 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: 1rem;
  background-color: var(--color-background);
}

.item-info {
  flex: 1;
}

.item-info h4 {
  margin-bottom: 0.5rem;
  color: var(--color-text-primary);
}

.item-info p {
  margin-bottom: 0.75rem;
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
}

.item-info a {
  color: var(--color-primary);
  text-decoration: none;
  font-size: var(--font-size-sm);
  transition: color var(--transition-fast);
}

.item-info a:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

.remove-btn {
  padding: 0.5rem 1rem;
  background-color: var(--color-error);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.remove-btn:hover {
  background-color: #c1271e;
}

.data-section {
  margin-bottom: 2.5rem;
}

.data-section h3 {
  margin-bottom: 1.5rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-xl);
  font-weight: 600;
}

.data-chart {
  margin-top: 2rem;
  background-color: var(--color-bg);
  padding: 1.5rem;
  border-radius: var(--radius-md);
}

.data-chart h4 {
  margin-bottom: 1.5rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-base);
  font-weight: 600;
}

.data-chart .data-cards {
  margin-bottom: 2rem;
}

.chart-placeholder {
  height: 300px;
  background-color: var(--color-bg-white);
  border-radius: var(--radius-md);
  display: flex;
  justify-content: center;
  align-items: center;
  color: var(--color-text-tertiary);
  border: 2px dashed var(--color-border);
  font-weight: 500;
}

.recent-study {
  margin-top: 2rem;
}

.recent-study h3 {
  margin-bottom: 1.5rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-xl);
  font-weight: 600;
}

.study-list {
  list-style: none;
  background-color: var(--color-bg);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.study-list li {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--color-border-light);
  transition: background-color var(--transition-fast);
}

.study-list li:hover {
  background-color: var(--color-border-light);
}

.study-list li:last-child {
  border-bottom: none;
}

.study-list li.no-data {
  text-align: center;
  color: var(--color-text-tertiary);
  padding: 2.5rem;
  font-weight: 500;
}

.filter-bar {
  background-color: var(--color-bg-white);
  padding: 1.25rem 1.5rem;
  margin: 0;
  border-radius: 0;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  align-items: center;
  position: sticky;
  top: 56px;
  left: 0;
  right: 0;
  z-index: 100;
}

.filter-section {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.filter-section label {
  font-weight: 500;
  color: var(--color-text-primary);
  white-space: nowrap;
  font-size: var(--font-size-sm);
}

.filter-section select {
  padding: 0.5rem 0.875rem;
  border: 2px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  outline: none;
  background-color: var(--color-bg-white);
  cursor: pointer;
  font-family: var(--font-family-base);
  transition: all var(--transition-fast);
  min-width: 120px;
}

.filter-section select:hover {
  border-color: var(--color-secondary);
}

.filter-section select:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.15);
}

.filter-btn {
  padding: 0.5rem 1.5rem;
  background-color: var(--color-primary);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: var(--font-family-base);
}

.filter-btn:hover {
  background-color: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

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

.filter-btn:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

.teaching-section {
  margin-bottom: 2.5rem;
}

.section-title {
  color: var(--color-text-primary);
  margin-bottom: 1.25rem;
  font-size: var(--font-size-2xl);
  border-bottom: 3px solid var(--color-primary);
  padding-bottom: 0.75rem;
  font-weight: 600;
  display: inline-block;
}

.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  padding: 1.25rem 0;
}

.tool-card {
  background-color: var(--color-bg-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  text-decoration: none;
  color: var(--color-text-primary);
  transition: all var(--transition-base);
  display: block;
}

.tool-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-primary);
}

.tool-card:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

.tool-info {
  text-align: center;
}

.tool-icon {
  margin-bottom: 1rem;
  font-size: 2.5rem;
}

.tool-title {
  margin-bottom: 0.5rem;
  color: var(--color-text-primary);
  font-size: var(--font-size-lg);
  font-weight: 600;
}

.tool-description {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  line-height: var(--line-height-relaxed);
  margin: 0;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  
  html {
    scroll-behavior: auto;
  }
}

@media (max-width: 1024px) {
  .school-name {
    transform: translate(-50%, -50%);
  }
  
  .school-name h1 {
    font-size: var(--font-size-3xl);
  }
  
  .school-name h2 {
    font-size: var(--font-size-xl);
  }
  
  .top-video {
    height: 60vh;
  }
  
  .profile-container {
    flex-direction: column;
  }
  
  .profile-sidebar {
    width: 100%;
    position: static;
  }
  
  .profile-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
  }
  
  .profile-nav li {
    flex: 1;
    min-width: 140px;
    margin-bottom: 0;
  }
}

@media (max-width: 768px) {
  .navbar-container {
    flex-direction: column;
    padding: 0.75rem 1rem;
    gap: 0.75rem;
  }
  
  .navbar-links {
    margin-top: 0;
    flex-wrap: wrap;
    justify-content: center;
    width: 100%;
  }
  
  .navbar-links li {
    margin: 0;
  }
  
  .navbar-links a {
    padding: 0.5rem 0.75rem;
    font-size: var(--font-size-xs);
  }
  
  .carousel {
    height: 280px;
  }
  
  .form-container {
    margin: 5rem 1rem 2rem;
    padding: 1.5rem;
  }
  
  .search-box {
    flex-direction: column;
  }
  
  .search-box input {
    width: 100%;
    border-radius: var(--radius-md);
  }
  
  .search-btn {
    width: 100%;
    border-radius: var(--radius-md);
    margin-top: 0.75rem;
  }
  
  .data-cards {
    flex-direction: column;
    align-items: center;
  }
  
  .data-card {
    width: 100%;
    max-width: 300px;
  }
  
  .course-grid {
    grid-template-columns: 1fr;
    padding: 0;
  }
  
  .filter-bar {
    flex-direction: column;
    align-items: stretch;
    padding: 1rem;
    top: 112px;
  }
  
  .filter-section {
    justify-content: space-between;
  }
  
  .filter-section select {
    flex: 1;
  }
  
  .tools-grid {
    grid-template-columns: 1fr;
    padding: 0;
  }
  
  .tool-site-container {
    flex-direction: column;
  }
  
  .content,
  .course-content {
    padding: 0 1rem;
  }
  
  .school-name h1 {
    font-size: var(--font-size-2xl);
  }
  
  .school-name h2 {
    font-size: var(--font-size-lg);
  }
  
  .top-video {
    height: 50vh;
    min-height: 400px;
  }
  
  .form-buttons {
    flex-direction: column;
  }
  
  .btn {
    width: 100%;
  }
  
  .course-center .carousel-control-prev,
  .course-center .carousel-control-next {
    width: 40px;
    height: 40px;
    font-size: 1rem;
  }
  
  .course-center .carousel-control-prev {
    left: 0.75rem;
  }
  
  .course-center .carousel-control-next {
    right: 0.75rem;
  }
  
  .course-center .carousel-caption {
    padding: 1.5rem 1rem 1rem;
  }
  
  .course-center .carousel-caption h3 {
    font-size: var(--font-size-lg);
  }
  
  .course-center .carousel-caption p {
    font-size: var(--font-size-sm);
  }
}

/* 登录页面样式 */
body {
  background: linear-gradient(135deg, #F0F7FF 0%, #FFFFFF 100%);
  min-height: 100vh;
}

.login-container {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: calc(100vh - 120px);
  padding: 2rem 1rem;
}

.login-card {
  width: 100%;
  max-width: 420px;
  background-color: white;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  padding: 40px 32px;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.login-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.12);
}

.tab-buttons {
  display: flex;
  margin-bottom: 2rem;
  border-bottom: 1px solid #E8F3FF;
}

.tab-btn {
  flex: 1;
  padding: 0.75rem 0;
  background: none;
  border: none;
  font-size: var(--font-size-base);
  font-weight: 600;
  color: #666666;
  cursor: pointer;
  transition: all 0.3s ease;
  position: relative;
}

.tab-btn:hover {
  color: #165DFF;
}

.tab-btn.active {
  color: #165DFF;
}

.tab-btn.active::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 3px;
  background-color: #165DFF;
  animation: slideIn 0.3s ease;
}

@keyframes slideIn {
  from {
    width: 0;
    left: 50%;
  }
  to {
    width: 100%;
    left: 0;
  }
}

.tab-content {
  display: none;
  animation: fadeIn 0.3s ease;
}

.tab-content.active {
  display: block;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.login-card h3 {
  margin-bottom: 2rem;
  color: #333333;
  font-size: var(--font-size-xl);
  font-weight: 600;
  text-align: center;
}

.form-group {
  margin-bottom: 1.5rem;
}

.input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
  border-bottom: 2px solid #E8F3FF;
  transition: all 0.3s ease;
}

.input-wrapper:focus-within {
  border-bottom-color: #165DFF;
  transform: translateY(-2px);
}

.input-wrapper i {
  color: #666666;
  margin-right: 0.75rem;
  font-size: var(--font-size-base);
  transition: color 0.3s ease;
}

.input-wrapper:focus-within i {
  color: #165DFF;
}

.input-wrapper input {
  flex: 1;
  padding: 0.75rem 0;
  border: none;
  outline: none;
  font-size: var(--font-size-base);
  color: #333333;
  background: transparent;
}

.input-wrapper input::placeholder {
  color: #999999;
}

.toggle-password {
  cursor: pointer;
  transition: color 0.3s ease;
}

.toggle-password:hover {
  color: #165DFF;
}

.form-options {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  font-size: var(--font-size-sm);
}

.remember-me {
  display: flex;
  align-items: center;
  cursor: pointer;
  color: #666666;
}

.remember-me input {
  margin-right: 0.5rem;
  accent-color: #165DFF;
}

.forgot-password {
  color: #165DFF;
  text-decoration: none;
  transition: color 0.3s ease;
}

.forgot-password:hover {
  color: #0E42C2;
  text-decoration: underline;
}

.login-btn, .register-btn {
  width: 100%;
  height: 44px;
  background: linear-gradient(135deg, #165DFF 0%, #0E42C2 100%);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: var(--font-size-base);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  margin-bottom: 1.5rem;
}

.login-btn:hover, .register-btn:hover {
  background: linear-gradient(135deg, #0E42C2 0%, #0A3191 100%);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(22, 93, 255, 0.3);
}

.login-btn:active, .register-btn:active {
  transform: translateY(0);
}

.switch-tab {
  text-align: center;
  font-size: var(--font-size-sm);
  color: #666666;
}

.switch-tab a {
  color: #165DFF;
  text-decoration: none;
  font-weight: 600;
  transition: color 0.3s ease;
}

.switch-tab a:hover {
  color: #0E42C2;
  text-decoration: underline;
}

/* 消息弹窗 */
.message-popup {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  justify-content: center;
  align-items: center;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s ease;
  z-index: 1000;
}

.message-popup.show {
  opacity: 1;
  visibility: visible;
}

.message-content {
  background-color: white;
  border-radius: 12px;
  padding: 2rem;
  text-align: center;
  max-width: 400px;
  width: 90%;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
  animation: popupIn 0.3s ease;
}

@keyframes popupIn {
  from {
    opacity: 0;
    transform: scale(0.8);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.message-content p {
  margin-bottom: 1.5rem;
  font-size: var(--font-size-base);
  color: #333333;
}

.message-popup.success p {
  color: #1e8e3e;
}

.message-popup.error p {
  color: #d93025;
}

.close-message {
  padding: 0.75rem 2rem;
  background-color: #165DFF;
  color: white;
  border: none;
  border-radius: 8px;
  font-size: var(--font-size-base);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
}

.close-message:hover {
  background-color: #0E42C2;
  transform: translateY(-1px);
}

/* 导航栏活跃状态 */
.navbar-links a.active {
  color: #165DFF;
  background-color: rgba(22, 93, 255, 0.1);
  font-weight: 600;
}

/* 视图切换按钮 */
.view-toggle {
  display: flex;
  justify-content: flex-end;
  gap: 0.5rem;
  margin: 1rem 0;
  padding: 0 1.5rem;
}

.view-btn {
  padding: 0.5rem 1rem;
  border: 1px solid var(--color-border);
  background-color: var(--color-bg-white);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.view-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.view-btn.active {
  background-color: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

/* 列表视图样式 */
.course-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.course-list .course-card {
  display: flex;
  flex-direction: row;
  align-items: stretch;
}

.course-list .course-image {
  width: 200px;
  height: auto;
  flex-shrink: 0;
}

.course-list .course-info {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

/* 重置按钮 */
.reset-btn {
  padding: 0.5rem 1rem;
  background-color: transparent;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  margin-left: 0.5rem;
}

.reset-btn:hover {
  background-color: var(--color-error-light);
  color: var(--color-error);
  border-color: var(--color-error);
}

@media (max-width: 768px) {
  .login-card {
    padding: 32px 24px;
  }
  
  .form-options {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.75rem;
  }
}

@media (max-width: 480px) {
  html {
    font-size: 14px;
  }
  
  .navbar-links {
    flex-direction: column;
    align-items: stretch;
    gap: 0.25rem;
  }
  
  .navbar-links li {
    margin: 0;
    width: 100%;
    text-align: center;
  }
  
  .navbar-links a {
    display: block;
    width: 100%;
    padding: 0.625rem;
  }
  
  .course-actions {
    flex-direction: column;
  }
  
  .profile-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
  }
  
  .profile-nav li {
    flex: 1;
    min-width: 100px;
    margin-bottom: 0;
  }
  
  .toggle-buttons {
    flex-direction: column;
  }
  
  .toggle-btn {
    width: 100%;
  }
  
  .top-video {
    height: 45vh;
    min-height: 350px;
  }
  
  .login-card {
    padding: 24px 20px;
  }
}