:root {
  --primary: #1a73e8;
  --primary-dark: #0d47a1;
  --primary-light: #e3f2fd;
  --accent: #00bcd4;
  --text-dark: #1a1a2e;
  --text-gray: #555;
  --text-light: #888;
  --bg-white: #fff;
  --bg-gray: #f5f8fe;
  --bg-dark: #0d47a1;
  --shadow: 0 4px 20px rgba(0,0,0,0.08);
  --shadow-hover: 0 8px 30px rgba(0,0,0,0.15);
  --radius: 12px;
  --transition: all 0.3s ease;
  --max-width: 1200px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text-dark);
  line-height: 1.6;
  background: var(--bg-white);
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; transform: scale(0.8); transform-origin: center center; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* Header / Navigation */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
  transition: var(--transition);
}

.header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary-dark);
}

.logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 1.1rem;
  font-weight: 700;
}

.nav { display: flex; align-items: center; gap: 5px; }

.nav a {
  padding: 8px 16px;
  border-radius: 6px;
  font-size: 0.9rem;
  color: var(--text-gray);
  transition: var(--transition);
  white-space: nowrap;
}

.nav a:hover,
.nav a.active {
  background: var(--primary-light);
  color: var(--primary);
}

.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 5px;
  background: none;
  border: none;
}

.mobile-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-dark);
  border-radius: 2px;
  transition: var(--transition);
}

/* Page Hero */
.page-hero {
  padding: 140px 0 60px;
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 50%, var(--accent) 100%);
  color: #fff;
  text-align: center;
}

.page-hero h1 {
  font-size: 2.8rem;
  margin-bottom: 16px;
  font-weight: 800;
}

.page-hero p {
  font-size: 1.15rem;
  opacity: 0.9;
  max-width: 700px;
  margin: 0 auto;
}

/* Sections */
.section {
  padding: 80px 0;
}

.section-title {
  text-align: center;
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary-dark);
  margin-bottom: 16px;
}

.section-subtitle {
  text-align: center;
  color: var(--text-gray);
  font-size: 1.05rem;
  max-width: 700px;
  margin: 0 auto 50px;
}

.section:nth-child(even) { background: var(--bg-gray); }

/* Cards */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
}

.card {
  background: var(--bg-white);
  border-radius: var(--radius);
  padding: 35px 30px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  border: 1px solid rgba(0,0,0,0.04);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.card-icon {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  margin-bottom: 20px;
}

.card-icon.blue { background: #e3f2fd; color: #1a73e8; }
.card-icon.green { background: #e8f5e9; color: #2e7d32; }
.card-icon.purple { background: #f3e5f5; color: #7b1fa2; }
.card-icon.orange { background: #fff3e0; color: #e65100; }
.card-icon.teal { background: #e0f2f1; color: #00695c; }
.card-icon.red { background: #ffebee; color: #c62828; }

.card h3 {
  font-size: 1.2rem;
  margin-bottom: 12px;
  color: var(--text-dark);
}

.card p {
  color: var(--text-gray);
  font-size: 0.95rem;
  line-height: 1.7;
}

.card-img {
  width: 100%;
  border-radius: 8px;
  margin-bottom: 16px;
  aspect-ratio: 4/3;
  object-fit: cover;
}

/* Timeline */
.timeline {
  position: relative;
  max-width: 800px;
  margin: 0 auto;
  padding-left: 40px;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 15px;
  top: 0;
  bottom: 0;
  width: 3px;
  background: linear-gradient(to bottom, var(--primary), var(--accent));
  border-radius: 2px;
}

.timeline-item {
  position: relative;
  padding: 0 0 50px 40px;
}

.timeline-item:last-child { padding-bottom: 0; }

.timeline-dot {
  position: absolute;
  left: -35px;
  top: 5px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--primary);
  border: 3px solid var(--bg-white);
  box-shadow: 0 0 0 3px var(--primary-light);
}

.timeline-date {
  font-size: 0.85rem;
  color: var(--primary);
  font-weight: 600;
  margin-bottom: 6px;
}

.timeline-content h3 {
  font-size: 1.15rem;
  margin-bottom: 8px;
}

.timeline-content p {
  color: var(--text-gray);
  font-size: 0.95rem;
}

/* Feature list */
.feature-list {
  max-width: 800px;
  margin: 0 auto;
}

.feature-item {
  display: flex;
  gap: 20px;
  padding: 25px 0;
  border-bottom: 1px solid rgba(0,0,0,0.06);
}

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

.feature-num {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
}

.feature-text h4 {
  font-size: 1.05rem;
  margin-bottom: 6px;
}

.feature-text p {
  color: var(--text-gray);
  font-size: 0.92rem;
}

/* Course Table */
.course-section {
  margin-bottom: 40px;
}

.course-section h3 {
  font-size: 1.3rem;
  color: var(--primary-dark);
  margin-bottom: 16px;
  padding-left: 16px;
  border-left: 4px solid var(--primary);
}

.course-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
}

.course-card {
  background: var(--bg-white);
  border: 1px solid rgba(0,0,0,0.06);
  border-radius: 10px;
  padding: 18px 20px;
  transition: var(--transition);
}

.course-card:hover {
  border-color: var(--primary);
  box-shadow: 0 4px 15px rgba(26,115,232,0.1);
}

.course-card .code {
  font-weight: 700;
  color: var(--primary);
  font-size: 0.85rem;
  margin-bottom: 4px;
}

.course-card .name {
  color: var(--text-dark);
  font-size: 0.95rem;
}

/* Achievement badges */
.badge-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.badge-item {
  background: var(--bg-white);
  border-radius: var(--radius);
  padding: 30px;
  text-align: center;
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,0,0,0.04);
}

.badge-icon {
  font-size: 2.8rem;
  margin-bottom: 16px;
}

.badge-item h4 {
  font-size: 1.1rem;
  margin-bottom: 8px;
}

.badge-item p {
  color: var(--text-gray);
  font-size: 0.9rem;
}

/* Contact page */
.contact-wrapper {
  display: grid;
  grid-template-columns: auto auto;
  gap: 30px;
  justify-content: center;
}

.contact-info h3 {
  font-size: 1.3rem;
  color: var(--primary-dark);
  margin-bottom: 24px;
}

.contact-detail {
  display: flex;
  align-items: flex-start;
  gap: 15px;
  margin-bottom: 20px;
}

.contact-detail .icon {
  flex-shrink: 0;
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
}

.contact-detail .label {
  font-size: 0.85rem;
  color: var(--text-light);
  margin-bottom: 2px;
}

.contact-detail .value {
  font-weight: 500;
}

.contact-form h3 {
  font-size: 1.3rem;
  color: var(--primary-dark);
  margin-bottom: 24px;
}

.form-group {
  margin-bottom: 18px;
}

.form-group label {
  display: block;
  font-size: 0.9rem;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--text-dark);
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 12px 16px;
  border: 1.5px solid #e0e0e0;
  border-radius: 8px;
  font-size: 0.95rem;
  transition: var(--transition);
  font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(26,115,232,0.1);
}

.form-group textarea {
  height: 120px;
  resize: vertical;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  font-family: inherit;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(26,115,232,0.35);
}

.btn-outline {
  background: transparent;
  color: #fff;
  border: 2px solid rgba(255,255,255,0.5);
}

.btn-outline:hover {
  border-color: #fff;
  background: rgba(255,255,255,0.1);
}

/* Home page specific */
.home-hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #0d47a1 0%, #1a73e8 50%, #00bcd4 100%);
  color: #fff;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.home-hero::before {
  content: '';
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  background: rgba(255,255,255,0.04);
  top: -200px;
  right: -200px;
}

.home-hero::after {
  content: '';
  position: absolute;
  width: 400px;
  height: 400px;
  border-radius: 50%;
  background: rgba(255,255,255,0.03);
  bottom: -150px;
  left: -150px;
}

.home-hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
  padding: 0 20px;
}

.home-hero .tagline {
  font-size: 1rem;
  letter-spacing: 6px;
  text-transform: uppercase;
  opacity: 0.8;
  margin-bottom: 24px;
  font-weight: 500;
}

.home-hero h1 {
  font-size: 3.8rem;
  font-weight: 800;
  margin-bottom: 12px;
  line-height: 1.2;
}

.home-hero h1 span {
  background: linear-gradient(to right, #fff, #80deea);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.home-hero .subtitle {
  font-size: 1.2rem;
  opacity: 0.9;
  margin-bottom: 40px;
  line-height: 1.7;
}

.home-hero .hero-btns {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* Overview section */
.overview-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.overview-card {
  text-align: center;
  padding: 40px 24px;
  border-radius: var(--radius);
  background: var(--bg-white);
  box-shadow: var(--shadow);
  transition: var(--transition);
  border: 1px solid rgba(0,0,0,0.04);
}

.overview-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.overview-card .emoji {
  font-size: 3rem;
  margin-bottom: 16px;
}

.overview-card h3 {
  font-size: 1.1rem;
  margin-bottom: 10px;
}

.overview-card p {
  color: var(--text-gray);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* Partnership page */
.partner-flow {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}

.partner-box {
  background: var(--bg-white);
  border-radius: var(--radius);
  padding: 36px;
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,0,0,0.04);
}

.partner-box h3 {
  font-size: 1.2rem;
  margin-bottom: 16px;
  color: var(--primary-dark);
}

.partner-box ul li {
  padding: 10px 0;
  padding-left: 24px;
  position: relative;
  color: var(--text-gray);
  font-size: 0.95rem;
}

.partner-box ul li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 700;
}

/* Footer */
.footer {
  background: var(--primary-dark);
  color: rgba(255,255,255,0.7);
  text-align: center;
  padding: 30px 20px;
  font-size: 0.9rem;
}

.footer a { color: rgba(255,255,255,0.9); }
.footer a:hover { color: #fff; }

/* Image styles */
.showcase-img {
  width: 100%;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.showcase-img:hover {
  box-shadow: var(--shadow-hover);
}

.showcase-wrapper {
  text-align: center;
  margin: 30px auto;
  max-width: 800px;
}

.showcase-wrapper img {
  width: 100%;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}


.img-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  margin: 30px 0;
}

.img-row img {
  width: 100%;
  border-radius: 10px;
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.img-row img:hover {
  transform: scale(1.02);
  box-shadow: var(--shadow-hover);
}

.img-grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin: 30px 0;
}

.img-grid-3 img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 10px;
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.img-grid-5 {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 20px;
  margin: 30px 0;
}

.img-grid-5 img {
  width: calc((100% - 40px) / 3);
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 10px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  filter: blur(1.5px);
}

.img-grid-5 img:hover {
  transform: scale(1.02);
  box-shadow: var(--shadow-hover);
}

@media (max-width: 768px) {
  .img-grid-5 img {
    width: calc((100% - 20px) / 2);
  }
}

@media (max-width: 480px) {
  .img-grid-5 img {
    width: 100%;
  }
}

@media (max-width: 768px) {
  .img-grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .img-grid-3 {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 1024px) {
  .card-grid[style*='repeat(4'],
  .card-grid[style*='repeat(3'] {
    grid-template-columns: repeat(2, 1fr) !important;
  }
}

.hero-img {
  max-height: 400px;
  width: auto;
  margin: 0 auto 30px;
  border-radius: var(--radius);
  box-shadow: 0 8px 40px rgba(0,0,0,0.2);
}

.home-hero-bg {
  position: absolute;
  right: -5%;
  top: 50%;
  transform: translateY(-50%);
  width: 45%;
  opacity: 0.15;
  pointer-events: none;
}

@media (max-width: 768px) {
  .home-hero-bg { display: none; }
  .hero-img { max-height: 250px; }
}

/* Animations */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Responsive */
@media (max-width: 1024px) {
  .page-hero h1 {
    font-size: 2.2rem;
  }
  .home-hero h1 {
    font-size: 2.8rem;
  }
  .partner-flow {
    grid-template-columns: 1fr;
  }
  .contact-wrapper {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .mobile-toggle { display: flex; }

  .nav {
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: var(--bg-white);
    flex-direction: column;
    padding: 20px;
    gap: 4px;
    border-bottom: 1px solid rgba(0,0,0,0.06);
    transform: translateY(-110%);
    opacity: 0;
    transition: var(--transition);
    box-shadow: var(--shadow);
  }

  .nav.open {
    transform: translateY(0);
    opacity: 1;
  }

  .nav a {
    width: 100%;
    padding: 12px 16px;
  }

  .home-hero h1 {
    font-size: 2rem;
  }

  .page-hero {
    padding: 120px 0 40px;
  }

  .page-hero h1 {
    font-size: 1.8rem;
  }

  .section {
    padding: 50px 0;
  }

  .section-title {
    font-size: 1.6rem;
  }

  .card-grid {
    grid-template-columns: 1fr;
  }

  .course-grid {
    grid-template-columns: 1fr;
  }

  .timeline {
    padding-left: 30px;
  }

  .timeline-item {
    padding-left: 30px;
  }

  .timeline-dot {
    left: -29px;
    width: 14px;
    height: 14px;
  }

  .feature-item {
    flex-direction: column;
    gap: 10px;
  }

  .home-hero .tagline {
    font-size: 0.85rem;
    letter-spacing: 4px;
  }

  .home-hero .subtitle {
    font-size: 1rem;
  }
}