:root {
  --navy: #0b2239;
  --navy-soft: #123a5f;
  --blue: #1f6feb;
  --cyan: #16a7b8;
  --ink: #1b2a3a;
  --muted: #5e6f80;
  --line: #dce5ee;
  --paper: #ffffff;
  --alt-bg: #f3f7fb;
  --shadow: 0 20px 45px rgba(11, 34, 57, 0.09);
  --radius: 18px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 86px;
}

body {
  margin: 0;
  color: var(--ink);
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", "Segoe UI", sans-serif;
  line-height: 1.75;
  background: var(--paper);
}

a {
  color: var(--blue);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid rgba(220, 229, 238, 0.9);
  backdrop-filter: blur(14px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 78px;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--navy);
}

.brand:hover {
  text-decoration: none;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border-radius: 14px;
  background: linear-gradient(135deg, var(--navy), var(--blue));
  color: #fff;
  font-weight: 800;
  letter-spacing: 0.04em;
  box-shadow: 0 8px 20px rgba(31, 111, 235, 0.25);
}

.brand-text {
  font-size: 18px;
  font-weight: 700;
  line-height: 1.2;
}

.brand-text small {
  display: block;
  color: var(--muted);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.03em;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.main-nav a {
  padding: 9px 12px;
  border-radius: 10px;
  color: #33475c;
  font-size: 14px;
  font-weight: 500;
  white-space: nowrap;
  transition: background 0.2s ease, color 0.2s ease;
}

.main-nav a:hover,
.main-nav a.active {
  background: #eaf2ff;
  color: var(--blue);
  text-decoration: none;
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 0;
  border-radius: 10px;
  background: #eaf2ff;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 5px auto;
  background: var(--navy);
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle.open span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.hero {
  position: relative;
  overflow: hidden;
  color: #fff;
  background:
    radial-gradient(circle at 78% 15%, rgba(31, 111, 235, 0.55), transparent 30%),
    radial-gradient(circle at 15% 85%, rgba(22, 167, 184, 0.42), transparent 28%),
    linear-gradient(135deg, #081a2c 0%, #0b2239 45%, #0f3f6b 100%);
}

.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.85), transparent);
}

.hero-inner {
  position: relative;
  z-index: 1;
  padding: 92px 0 100px;
  max-width: 900px;
}

.eyebrow {
  margin: 0 0 22px;
  color: #b9d8ff;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.08em;
}

.hero h1 {
  margin: 0 0 22px;
  font-size: clamp(40px, 7vw, 72px);
  line-height: 1.08;
  letter-spacing: -0.04em;
}

.hero-subtitle {
  max-width: 720px;
  margin: 0;
  color: #d9e7f5;
  font-size: clamp(17px, 2vw, 22px);
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 34px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 20px;
  border-radius: 12px;
  font-size: 15px;
  font-weight: 600;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
  text-decoration: none;
}

.btn-primary {
  background: #fff;
  color: var(--navy);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.18);
}

.btn-ghost {
  border: 1px solid rgba(255, 255, 255, 0.42);
  color: #fff;
  background: rgba(255, 255, 255, 0.06);
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 34px;
}

.hero-badges span {
  padding: 7px 12px;
  border: 1px solid rgba(255, 255, 255, 0.24);
  border-radius: 999px;
  color: #e8f3ff;
  font-size: 13px;
  background: rgba(255, 255, 255, 0.08);
}

.section {
  padding: 84px 0;
}

.section-alt {
  background: var(--alt-bg);
}

.section-heading {
  display: flex;
  align-items: flex-start;
  gap: 18px;
  margin-bottom: 34px;
}

.section-index {
  display: inline-grid;
  place-items: center;
  width: 44px;
  height: 44px;
  flex: 0 0 44px;
  border-radius: 12px;
  background: #eaf2ff;
  color: var(--blue);
  font-size: 14px;
  font-weight: 700;
}

.section-heading h2 {
  margin: 0;
  color: var(--navy);
  font-size: clamp(26px, 3vw, 38px);
  line-height: 1.2;
}

.section-subtitle {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 14px;
  letter-spacing: 0.06em;
}

.section-note {
  max-width: 860px;
  margin: -16px 0 24px 62px;
  color: var(--muted);
  font-size: 14px;
}

.overview-grid,
.staff-grid,
.resource-grid,
.project-grid {
  display: grid;
  gap: 22px;
}

.overview-grid {
  grid-template-columns: 1.25fr 0.75fr;
}

.topic-panel {
  margin-top: 22px;
  padding: 26px 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(135deg, #f4f8ff, #eef6f7);
  box-shadow: var(--shadow);
}

.topic-panel h3 {
  margin: 0 0 18px;
  color: var(--navy);
  font-size: 18px;
}

.topic-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.topic-list li {
  padding: 7px 13px;
  border: 1px solid #cfe0f7;
  border-radius: 999px;
  background: #fff;
  color: var(--navy-soft);
  font-size: 14px;
  font-weight: 500;
}

.lead-card,
.outcome-card,
.staff-card,
.resource-card,
.project-timeline,
.project-topics,
.project-deliverable,
.grading-note {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.lead-card {
  padding: 30px;
}

.lead-card p {
  margin: 0 0 18px;
  font-size: 17px;
}

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

.outcome-card {
  padding: 28px;
  background: linear-gradient(135deg, #f4f8ff, #eef6f7);
}

.outcome-card h3,
.project-timeline h3,
.project-topics h3,
.project-deliverable h3,
.grading-note h3 {
  margin: 0 0 16px;
  color: var(--navy);
  font-size: 18px;
}

.outcome-card ul,
.project-topics ul,
.resource-card ul {
  margin: 0;
  padding-left: 20px;
}

.outcome-card li,
.project-topics li,
.resource-card li {
  margin: 9px 0;
}

.staff-grid {
  grid-template-columns: repeat(2, 1fr);
}

.staff-card {
  display: flex;
  gap: 20px;
  padding: 26px;
}

.avatar {
  display: grid;
  place-items: center;
  width: 74px;
  height: 74px;
  flex: 0 0 74px;
  border-radius: 20px;
  background: linear-gradient(135deg, var(--navy), var(--blue));
  color: #fff;
  font-size: 20px;
  font-weight: 800;
}

.staff-info h3 {
  margin: 0 0 4px;
  color: var(--navy);
  font-size: 20px;
}

.staff-info h3 span {
  color: var(--muted);
  font-size: 15px;
  font-weight: 500;
}

.staff-info p {
  margin: 5px 0;
  color: #42566b;
}

.staff-info .role {
  color: var(--blue);
  font-weight: 600;
}

.info-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.info-item {
  display: flex;
  gap: 16px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.info-icon {
  font-size: 26px;
}

.info-item h3 {
  margin: 0 0 8px;
  color: var(--navy);
  font-size: 17px;
}

.info-item p {
  margin: 0;
  color: var(--muted);
}

.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
}

.schedule-table {
  width: 100%;
  min-width: 860px;
  border-collapse: collapse;
}

.schedule-table th,
.schedule-table td {
  padding: 16px 18px;
  border-bottom: 1px solid #e6edf5;
  text-align: left;
  vertical-align: top;
  font-size: 14px;
}

.schedule-table th {
  background: var(--navy);
  color: #fff;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.schedule-table tbody tr:hover {
  background: #f7fbff;
}

.schedule-table tbody tr:last-child td {
  border-bottom: 0;
}

.tag {
  display: inline-block;
  padding: 4px 9px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  white-space: nowrap;
}

.tag-theory {
  background: #eaf2ff;
  color: #1f6feb;
}

.tag-lab {
  background: #e8f8f5;
  color: #0b7c73;
}

.tag-project {
  background: #fff2e5;
  color: #c15b14;
}

.grading-layout {
  display: grid;
  grid-template-columns: 1.5fr 0.7fr;
  gap: 22px;
}

.grading-list {
  padding: 10px 0;
}

.grading-row {
  display: grid;
  grid-template-columns: 130px 1fr 58px;
  align-items: center;
  gap: 16px;
  margin: 18px 0;
}

.grading-name {
  color: var(--navy);
  font-weight: 600;
}

.grading-bar {
  height: 12px;
  overflow: hidden;
  border-radius: 999px;
  background: #e8eef5;
}

.grading-bar span {
  display: block;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--blue), var(--cyan));
}

.grading-percent {
  color: var(--muted);
  font-weight: 700;
  text-align: right;
}

.grading-note {
  align-self: start;
  padding: 26px;
}

.grading-note p {
  margin: 0 0 12px;
  color: var(--muted);
  font-size: 14px;
}

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

.project-timeline,
.project-topics,
.project-deliverable {
  padding: 26px;
}

.timeline {
  margin: 0;
  padding: 0;
  list-style: none;
}

.timeline li {
  position: relative;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  padding: 0 0 22px 24px;
  border-left: 2px solid #cfe0f7;
}

.timeline li:last-child {
  padding-bottom: 0;
  border-left-color: transparent;
}

.timeline li::before {
  content: "";
  position: absolute;
  left: -6px;
  top: 2px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--blue);
  box-shadow: 0 0 0 4px #eaf2ff;
}

.timeline span {
  color: var(--muted);
  font-size: 13px;
  white-space: nowrap;
}

.project-deliverable p {
  margin: 0;
  color: #42566b;
}

.resource-grid {
  grid-template-columns: repeat(2, 1fr);
}

.resource-card {
  padding: 26px;
}

.resource-card h3 {
  margin: 0 0 14px;
  color: var(--navy);
  font-size: 18px;
}

.faq-list {
  max-width: 880px;
}

.faq-list details {
  margin-bottom: 12px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
  overflow: hidden;
}

.faq-list summary {
  padding: 18px 22px;
  color: var(--navy);
  font-weight: 600;
  cursor: pointer;
  list-style: none;
}

.faq-list summary::-webkit-details-marker {
  display: none;
}

.faq-list summary::after {
  content: "+";
  float: right;
  color: var(--blue);
  font-size: 22px;
  line-height: 1;
}

.faq-list details[open] summary::after {
  content: "−";
}

.faq-list details p {
  margin: 0;
  padding: 0 22px 20px;
  color: #42566b;
}

.site-footer {
  padding: 42px 0;
  background: var(--navy);
  color: #d9e7f5;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.footer-inner strong {
  color: #fff;
  font-size: 17px;
}

.footer-inner p {
  margin: 5px 0 0;
  font-size: 13px;
  color: #a9c0d4;
}

.footer-note {
  max-width: 420px;
  text-align: right;
}

@media (max-width: 900px) {
  .main-nav {
    position: absolute;
    top: 78px;
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 12px 20px 20px;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: 0 20px 30px rgba(11, 34, 57, 0.08);
  }

  .main-nav.open {
    display: flex;
  }

  .main-nav a {
    padding: 12px;
  }

  .nav-toggle {
    display: block;
  }

  .overview-grid,
  .staff-grid,
  .grading-layout,
  .project-grid,
  .resource-grid {
    grid-template-columns: 1fr;
  }

  .section-note {
    margin-left: 0;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-note {
    text-align: left;
  }
}

@media (max-width: 560px) {
  .hero-inner {
    padding: 64px 0 72px;
  }

  .section {
    padding: 60px 0;
  }

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

  .grading-row {
    grid-template-columns: 90px 1fr 48px;
    gap: 10px;
  }

  .lead-card,
  .outcome-card,
  .staff-card,
  .info-item,
  .project-timeline,
  .project-topics,
  .project-deliverable,
  .resource-card {
    padding: 20px;
  }
}