:root {
  color-scheme: light;
  --ink: #17212b;
  --muted: #66727d;
  --paper: #fbfaf6;
  --panel: #ffffff;
  --line: #dde5e4;
  --teal: #176c72;
  --teal-deep: #0f4a55;
  --gold: #d59c3f;
  --night: #102033;
  --radius: 8px;
  --shadow: 0 24px 70px rgba(22, 37, 45, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  background: var(--paper);
  color: var(--ink);
  font-family:
    "Inter", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui,
    -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
}

a {
  color: inherit;
  text-decoration: none;
}

.site-header {
  position: fixed;
  top: 0;
  right: 0;
  left: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(18px, 4vw, 56px);
  color: #f7f1df;
  background: linear-gradient(180deg, rgba(9, 22, 32, 0.78), rgba(9, 22, 32, 0));
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  min-width: 0;
  font-size: 15px;
  font-weight: 700;
  white-space: nowrap;
}

.brand-mark {
  display: inline-grid;
  flex: 0 0 auto;
  width: 34px;
  height: 34px;
  place-items: center;
  border: 1px solid rgba(247, 241, 223, 0.44);
  border-radius: 50%;
  background: rgba(247, 241, 223, 0.12);
  color: #f6d68e;
  font-weight: 800;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: clamp(14px, 3vw, 30px);
  color: rgba(247, 241, 223, 0.84);
  font-size: 14px;
}

.nav-links a {
  padding: 6px 0;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: #ffffff;
}

.hero {
  position: relative;
  display: grid;
  min-height: 92svh;
  overflow: hidden;
  background: var(--night);
}

.hero-visual,
.hero-shade {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-visual {
  object-fit: cover;
}

.hero-shade {
  background:
    linear-gradient(90deg, rgba(9, 22, 32, 0.88) 0%, rgba(9, 22, 32, 0.72) 34%, rgba(9, 22, 32, 0.18) 72%),
    linear-gradient(180deg, rgba(9, 22, 32, 0.18), rgba(9, 22, 32, 0.38));
}

.hero-content {
  position: relative;
  z-index: 1;
  align-self: center;
  width: min(760px, calc(100% - 36px));
  margin: 0 auto;
  padding: 132px 0 86px;
  color: #fffaf0;
}

.eyebrow {
  margin: 0 0 14px;
  color: #f0c66a;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.eyebrow.dark {
  color: var(--teal);
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1 {
  max-width: 650px;
  margin: 0;
  font-size: clamp(40px, 7.2vw, 86px);
  line-height: 1.06;
  letter-spacing: 0;
}

.hero-copy {
  max-width: 610px;
  margin: 24px 0 0;
  color: rgba(255, 250, 240, 0.84);
  font-size: clamp(17px, 2.2vw, 22px);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 36px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 11px 18px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 700;
}

.button.primary {
  background: #f0c66a;
  color: #16212a;
}

.button.secondary {
  border-color: rgba(255, 250, 240, 0.36);
  background: rgba(255, 250, 240, 0.08);
  color: #fffaf0;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-1px);
}

.section {
  width: min(1120px, calc(100% - 36px));
  margin: 0 auto;
  padding: 84px 0;
}

.section-heading {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(280px, 1.2fr);
  gap: 28px;
  align-items: end;
  margin-bottom: 32px;
}

.section-heading.compact {
  display: block;
  margin-bottom: 24px;
}

.section-heading h2,
.about h2 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(28px, 4vw, 46px);
  line-height: 1.16;
  letter-spacing: 0;
}

.section-heading p:last-child,
.about > p {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
}

.note-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.note-card {
  min-height: 248px;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: var(--shadow);
}

.note-meta {
  margin: 0 0 46px;
  color: var(--teal);
  font-size: 13px;
  font-weight: 800;
}

.note-card h3 {
  margin: 0 0 14px;
  font-size: 21px;
  line-height: 1.28;
}

.note-card p:last-child {
  margin: 0;
  color: var(--muted);
}

.topics {
  padding-top: 18px;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 10px;
}

.topic-grid span {
  display: grid;
  min-height: 58px;
  place-items: center;
  padding: 10px;
  border: 1px solid #cbd9d8;
  border-radius: var(--radius);
  background: #eef4ef;
  color: #21434a;
  font-size: 14px;
  font-weight: 700;
  text-align: center;
}

.about {
  display: grid;
  grid-template-columns: minmax(0, 0.72fr) minmax(280px, 1fr);
  gap: 34px;
  align-items: start;
  border-top: 1px solid var(--line);
}

.site-footer {
  background: #0f1e2a;
  color: rgba(255, 250, 240, 0.82);
}

.footer-inner {
  display: flex;
  width: min(1120px, calc(100% - 36px));
  margin: 0 auto;
  padding: 34px 0;
  align-items: flex-start;
  justify-content: space-between;
  gap: 28px;
}

.footer-brand {
  margin: 0;
  color: #fffaf0;
  font-weight: 800;
}

.beian {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  max-width: 620px;
  color: rgba(255, 250, 240, 0.72);
  font-size: 13px;
  line-height: 1.55;
}

.beian,
.beian a,
.beian span {
  margin: 0;
}

.beian a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: #fffaf0;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.beian img {
  display: block;
  width: 18px;
  height: 18px;
  flex: 0 0 auto;
}

.beian a:hover,
.beian a:focus-visible {
  color: #f0c66a;
}

@media (max-width: 820px) {
  .site-header {
    align-items: flex-start;
  }

  .brand {
    white-space: normal;
    line-height: 1.25;
  }

  .nav-links {
    flex: 0 0 auto;
  }

  .hero {
    min-height: 88svh;
  }

  .hero-shade {
    background:
      linear-gradient(90deg, rgba(9, 22, 32, 0.88), rgba(9, 22, 32, 0.48)),
      linear-gradient(180deg, rgba(9, 22, 32, 0.08), rgba(9, 22, 32, 0.52));
  }

  .hero-content {
    padding-top: 118px;
  }

  .section-heading,
  .about {
    grid-template-columns: 1fr;
  }

  .note-list {
    grid-template-columns: 1fr;
  }

  .note-card {
    min-height: auto;
  }

  .note-meta {
    margin-bottom: 32px;
  }

  .topic-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .footer-inner {
    flex-direction: column;
  }
}

@media (max-width: 560px) {
  .site-header {
    position: absolute;
    display: grid;
    gap: 12px;
  }

  .nav-links {
    width: 100%;
    justify-content: space-between;
  }

  .hero-content {
    width: min(100% - 32px, 760px);
    padding-bottom: 72px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .button {
    width: 100%;
  }

  .section {
    width: min(100% - 32px, 1120px);
    padding: 64px 0;
  }

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