:root {
  --bg: #f5f7fb;
  --bg-2: #eef2f8;
  --surface: rgba(255, 255, 255, 0.68);
  --surface-strong: rgba(255, 255, 255, 0.9);
  --line: rgba(15, 23, 42, 0.1);
  --text: #0f172a;
  --muted: #475569;
  --blue: #0a84ff;
  --blue-deep: #005dd6;
  --radius-lg: 24px;
  --radius-md: 16px;
  --shadow: 0 24px 60px rgba(15, 23, 42, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(circle at 8% 0%, rgba(126, 181, 255, 0.28), transparent 34%),
    radial-gradient(circle at 92% 10%, rgba(120, 232, 255, 0.22), transparent 38%),
    linear-gradient(180deg, var(--bg), var(--bg-2));
  font-family:
    "SF Pro Display",
    "SF Pro Text",
    "PingFang SC",
    "Hiragino Sans GB",
    "Microsoft YaHei",
    "Helvetica Neue",
    sans-serif;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

.container {
  width: min(1120px, 92vw);
  margin: 0 auto;
}

.ambient {
  position: fixed;
  z-index: -1;
  width: 460px;
  height: 460px;
  filter: blur(70px);
  opacity: 0.4;
  pointer-events: none;
  animation: float 12s ease-in-out infinite;
}

.ambient-a {
  top: -150px;
  left: -140px;
  background: radial-gradient(circle, #93c5fd 0%, transparent 70%);
}

.ambient-b {
  right: -180px;
  bottom: -160px;
  background: radial-gradient(circle, #67e8f9 0%, transparent 72%);
  animation-delay: -5s;
}

@keyframes float {
  0%,
  100% {
    transform: translateY(0) scale(1);
  }
  50% {
    transform: translateY(-18px) scale(1.04);
  }
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(16px) saturate(130%);
  background: rgba(245, 247, 251, 0.74);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  text-decoration: none;
  font-weight: 700;
}

.brand-mark {
  width: 34px;
  height: 34px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  color: #fff;
  background: linear-gradient(135deg, #0f172a, #1d4ed8);
  box-shadow: 0 10px 24px rgba(29, 78, 216, 0.32);
}

.nav {
  display: flex;
  align-items: center;
  gap: 22px;
}

.nav a {
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  font-weight: 600;
  transition: color 0.2s ease;
}

.nav a:hover,
.nav a.active {
  color: var(--text);
}

.menu-toggle {
  display: none;
  width: 38px;
  height: 38px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 0;
}

.menu-toggle span {
  display: block;
  width: 16px;
  height: 2px;
  margin: 3px auto;
  border-radius: 9px;
  background: var(--text);
}

.scroll-progress {
  height: 2px;
  transform-origin: left center;
  transform: scaleX(0);
  background: linear-gradient(90deg, #6cb4ff, var(--blue));
}

.hero {
  padding: 92px 0 42px;
}

.eyebrow {
  margin: 0;
  display: inline-flex;
  padding: 7px 13px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: #175ab4;
  border: 1px solid rgba(23, 90, 180, 0.22);
  background: rgba(23, 90, 180, 0.1);
}

h1 {
  margin: 16px 0 10px;
  font-size: clamp(46px, 9vw, 82px);
  line-height: 1.02;
  letter-spacing: -0.03em;
}

.subtitle {
  margin: 0;
  font-size: clamp(20px, 3vw, 28px);
  color: #1e293b;
  font-weight: 630;
}

.intro {
  margin: 14px 0 0;
  max-width: 760px;
  color: var(--muted);
  line-height: 1.84;
}

.hero-actions {
  margin-top: 24px;
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  padding: 11px 19px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 620;
  transition:
    transform 0.2s ease,
    box-shadow 0.2s ease;
}

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

.btn-primary {
  color: #fff;
  background: linear-gradient(135deg, var(--blue), var(--blue-deep));
  box-shadow: 0 14px 30px rgba(10, 132, 255, 0.28);
}

.btn-ghost {
  color: var(--text);
  border: 1px solid var(--line);
  background: var(--surface);
}

.meta-list {
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
  color: #334155;
  font-size: 14px;
}

.stat-grid {
  margin-top: 24px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.stat-grid article {
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: var(--surface-strong);
  box-shadow: var(--shadow);
  padding: 16px;
}

.stat-grid h3 {
  margin: 0;
  font-size: clamp(22px, 3vw, 30px);
  line-height: 1.2;
}

.stat-grid p {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.section {
  padding: 30px 0;
}

.section-head h2 {
  margin: 0 0 14px;
  font-size: clamp(28px, 5vw, 40px);
  letter-spacing: -0.02em;
}

.grid-two,
.project-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.card,
.timeline-item,
.contact-card {
  border-radius: var(--radius-lg);
  border: 1px solid var(--line);
  background: var(--surface-strong);
  box-shadow: var(--shadow);
  padding: 22px;
}

.card.highlight {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.96), rgba(255, 255, 255, 0.74)),
    radial-gradient(circle at 88% 0%, rgba(10, 132, 255, 0.22), transparent 35%);
}

.time {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: #1d4ed8;
}

.card h3 {
  margin: 8px 0 10px;
  font-size: clamp(18px, 2.5vw, 24px);
}

.card p,
.timeline-item p,
.card li,
.contact-card p {
  margin: 0;
  color: #334155;
  line-height: 1.78;
}

.card ul {
  margin: 0;
  padding-left: 18px;
}

.card li + li {
  margin-top: 6px;
}

.result {
  margin-top: 10px !important;
  color: #0f4e9f !important;
  font-weight: 600;
}

.chip-wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.chip {
  padding: 9px 14px;
  border-radius: 999px;
  border: 1px solid rgba(16, 108, 214, 0.2);
  background: rgba(16, 108, 214, 0.08);
  color: #0f5bb2;
  font-size: 13px;
  font-weight: 620;
}

.timeline {
  display: grid;
  gap: 12px;
}

.contact-card {
  text-align: center;
  padding: 34px;
}

.contact-card h2 {
  margin: 0;
  font-size: clamp(28px, 4.6vw, 42px);
  letter-spacing: -0.02em;
}

.contact-card p {
  margin-top: 10px;
}

.contact-card .hero-actions {
  justify-content: center;
}

.site-footer {
  padding: 34px 0 48px;
}

.footer-inner {
  border-top: 1px solid var(--line);
  padding-top: 16px;
}

.site-footer p {
  margin: 0;
  font-size: 13px;
  color: #64748b;
}

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition:
    opacity 0.5s ease,
    transform 0.5s ease;
}

.reveal.show {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 900px) {
  .menu-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
  }

  .nav {
    position: absolute;
    left: 4vw;
    right: 4vw;
    top: 72px;
    border-radius: 18px;
    border: 1px solid var(--line);
    background: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow);
    display: none;
    flex-direction: column;
    align-items: flex-start;
    padding: 12px;
    gap: 10px;
  }

  .nav.open {
    display: flex;
  }

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

@media (max-width: 640px) {
  .hero {
    padding-top: 74px;
  }

  .card,
  .timeline-item,
  .contact-card {
    padding: 18px;
  }
}