:root {
  --ink: #132c35;
  --muted: #52676e;
  --paper: #f5f2e9;
  --card: #fffdf8;
  --line: #cfd7d3;
  --teal: #176e75;
  --teal-dark: #104c52;
  --orange: #e46f2e;
  --lime: #dce89b;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 90% 1%, rgb(220 232 155 / 62%), transparent 21rem),
    linear-gradient(90deg, rgb(19 44 53 / 4%) 1px, transparent 1px),
    var(--paper);
  background-size: auto, 36px 36px, auto;
  font-family: "Avenir Next", "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.7;
}

a {
  color: inherit;
}

.skip-link {
  padding: 9px 14px;
  color: #fff;
  background: var(--teal-dark);
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 20;
  transform: translateY(-150%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  min-height: 76px;
  padding: 0 clamp(22px, 5vw, 76px);
  background: rgb(245 242 233 / 88%);
  border-bottom: 1px solid rgb(19 44 53 / 12%);
  backdrop-filter: blur(16px);
  display: flex;
  align-items: center;
  gap: 34px;
  position: sticky;
  top: 0;
  z-index: 10;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}

.brand span {
  width: 36px;
  height: 36px;
  color: #fff;
  background: var(--teal-dark);
  border-radius: 50% 50% 50% 10px;
  display: grid;
  place-items: center;
  font-size: 12px;
  font-weight: 900;
  letter-spacing: -0.04em;
}

.brand strong {
  font-size: 18px;
  letter-spacing: -0.02em;
}

.site-header nav {
  margin-left: auto;
  display: flex;
  gap: 28px;
}

.site-header nav a {
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
}

.site-header nav a:hover {
  color: var(--teal);
}

.header-cta,
.hero-actions a,
.final-cta > a {
  border-radius: 99px;
  font-weight: 800;
  text-decoration: none;
}

.header-cta {
  padding: 9px 16px;
  color: #fff;
  background: var(--teal-dark);
  font-size: 13px;
}

main,
footer {
  width: min(1180px, calc(100% - 44px));
  margin-inline: auto;
}

.hero {
  min-height: 690px;
  padding: 84px 0 68px;
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(460px, 1.1fr);
  align-items: center;
  gap: clamp(42px, 7vw, 96px);
}

.kicker,
.section-number {
  margin: 0;
  color: var(--orange);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: 0.16em;
}

.hero h1 {
  max-width: 620px;
  margin: 14px 0 24px;
  font-family: "Songti SC", "STSong", serif;
  font-size: clamp(48px, 6vw, 82px);
  font-weight: 800;
  line-height: 1.04;
  letter-spacing: -0.05em;
}

.lede {
  max-width: 600px;
  margin: 0;
  color: var(--muted);
  font-size: clamp(18px, 2vw, 22px);
  line-height: 1.75;
}

.hero-actions {
  margin-top: 34px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.hero-actions a {
  padding: 13px 21px;
}

.hero-actions .primary {
  color: #fff;
  background: var(--teal-dark);
  box-shadow: 0 8px 24px rgb(16 76 82 / 18%);
}

.hero-actions .secondary {
  border: 1px solid var(--teal-dark);
}

.hero-facts {
  margin: 44px 0 0;
  display: flex;
  gap: 34px;
}

.hero-facts div {
  padding-left: 12px;
  border-left: 2px solid var(--orange);
}

.hero-facts dt {
  color: var(--muted);
  font-size: 11px;
}

.hero-facts dd {
  margin: 0;
  font-weight: 800;
}

.hero-visual {
  margin: 0;
  padding: 15px;
  background: #fff;
  border: 1px solid rgb(19 44 53 / 18%);
  border-radius: 10px 10px 56px 10px;
  box-shadow: 18px 22px 0 var(--lime), 0 20px 60px rgb(19 44 53 / 14%);
  transform: rotate(1.3deg);
}

.hero-visual img {
  width: 100%;
  height: auto;
  border-radius: 5px 5px 44px 5px;
  display: block;
}

.hero-visual figcaption {
  padding: 11px 4px 0;
  color: var(--muted);
  font-size: 11px;
}

.boundary {
  padding: 18px 22px;
  color: #fff;
  background: var(--teal-dark);
  border-radius: 8px;
  display: grid;
  grid-template-columns: 150px minmax(0, 1fr);
  gap: 20px;
}

.boundary p {
  margin: 0;
  color: #dce9e6;
  font-size: 13px;
}

.section-grid,
.path,
.modules,
.questions {
  padding: 110px 0;
}

.section-grid {
  display: grid;
  grid-template-columns: minmax(250px, 0.7fr) minmax(0, 1.3fr);
  gap: clamp(40px, 8vw, 120px);
}

.section-grid h2,
.section-heading h2 {
  margin: 10px 0 0;
  font-family: "Songti SC", "STSong", serif;
  font-size: clamp(34px, 4vw, 52px);
  line-height: 1.18;
  letter-spacing: -0.035em;
}

.prose p {
  margin: 0 0 20px;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.9;
}

.section-heading {
  margin-bottom: 40px;
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 40px;
}

.section-heading > p {
  max-width: 470px;
  margin: 0;
  color: var(--muted);
}

.path {
  border-top: 1px solid rgb(19 44 53 / 18%);
}

.path-list {
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--ink);
  list-style: none;
}

.path-list li {
  padding: 24px 10px;
  border-bottom: 1px solid rgb(19 44 53 / 22%);
  display: grid;
  grid-template-columns: 80px minmax(0, 1fr);
  gap: 12px;
  transition: background 180ms ease, padding 180ms ease;
}

.path-list li:hover {
  padding-inline: 22px;
  background: rgb(255 253 248 / 62%);
}

.path-list > li > span {
  color: var(--orange);
  font-size: 12px;
  font-weight: 900;
}

.path-list h3 {
  margin: 0 0 5px;
  font-size: 20px;
}

.path-list p {
  margin: 0;
  color: var(--muted);
}

.modules {
  padding-inline: clamp(22px, 5vw, 68px);
  background: var(--ink);
  border-radius: 12px 12px 78px 12px;
}

.modules .section-heading h2,
.modules .section-heading > p {
  color: #fff;
}

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

.module-grid article {
  min-height: 260px;
  padding: 28px;
  background: #f4f0e4;
  border-radius: 7px;
  display: flex;
  flex-direction: column;
}

.module-grid article:nth-child(2),
.module-grid article:nth-child(3) {
  background: var(--lime);
}

.module-grid article > span {
  color: var(--teal);
  font-size: 10px;
  font-weight: 900;
  letter-spacing: 0.14em;
}

.module-grid h3 {
  margin: 24px 0 10px;
  font-size: 23px;
}

.module-grid p {
  margin: 0;
  color: #4c626a;
}

.module-grid a {
  margin-top: auto;
  padding-top: 22px;
  color: var(--teal-dark);
  font-size: 13px;
  font-weight: 900;
}

.practice-list {
  display: grid;
  gap: 24px;
}

.practice-list div {
  padding: 0 0 24px 48px;
  border-bottom: 1px solid rgb(19 44 53 / 20%);
  position: relative;
}

.practice-list div::before {
  content: "✓";
  width: 30px;
  height: 30px;
  color: #fff;
  background: var(--teal);
  border-radius: 50%;
  display: grid;
  place-items: center;
  position: absolute;
  left: 0;
  top: 0;
  font-weight: 900;
}

.practice-list b {
  font-size: 18px;
}

.practice-list p {
  margin: 5px 0 0;
  color: var(--muted);
}

.questions {
  border-top: 1px solid rgb(19 44 53 / 18%);
}

.question-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.question-list details {
  padding: 20px 22px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 6px;
}

.question-list summary {
  font-weight: 800;
  cursor: pointer;
}

.question-list p {
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 14px;
}

.final-cta {
  margin-bottom: 90px;
  padding: clamp(48px, 8vw, 92px);
  color: #fff;
  background:
    radial-gradient(circle at 90% 10%, rgb(220 232 155 / 32%), transparent 28%),
    var(--teal-dark);
  border-radius: 12px 12px 70px 12px;
  text-align: center;
}

.final-cta p {
  margin: 0;
  color: var(--lime);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: 0.16em;
}

.final-cta h2 {
  margin: 16px 0 8px;
  font-family: "Songti SC", "STSong", serif;
  font-size: clamp(36px, 5vw, 62px);
  line-height: 1.2;
}

.final-cta > span {
  color: #d4e3e1;
}

.final-cta > a {
  width: fit-content;
  margin: 30px auto 0;
  padding: 13px 26px;
  color: var(--teal-dark);
  background: var(--lime);
  display: block;
}

footer {
  padding: 38px 0 58px;
  border-top: 1px solid rgb(19 44 53 / 18%);
}

.footer-brand {
  margin-bottom: 16px;
}

footer p {
  max-width: 920px;
  margin: 6px 0;
  color: var(--muted);
  font-size: 12px;
}

@media (max-width: 940px) {
  .site-header nav {
    display: none;
  }

  .header-cta {
    margin-left: auto;
  }

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

  .hero-visual {
    max-width: 720px;
  }

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

@media (max-width: 680px) {
  body {
    background-size: auto, 24px 24px, auto;
  }

  .site-header {
    min-height: 66px;
    padding-inline: 18px;
  }

  .brand strong {
    font-size: 15px;
  }

  .header-cta {
    padding: 8px 12px;
    font-size: 11px;
  }

  main,
  footer {
    width: min(100% - 30px, 1180px);
  }

  .hero {
    min-height: auto;
    padding: 62px 0 74px;
    gap: 48px;
  }

  .hero h1 {
    font-size: clamp(44px, 15vw, 62px);
  }

  .hero-facts {
    gap: 16px;
  }

  .hero-visual {
    margin-right: 12px;
    box-shadow: 11px 13px 0 var(--lime), 0 16px 44px rgb(19 44 53 / 13%);
  }

  .boundary {
    grid-template-columns: minmax(0, 1fr);
    gap: 5px;
  }

  .section-grid,
  .path,
  .modules,
  .questions {
    padding-block: 76px;
  }

  .section-heading {
    align-items: flex-start;
    flex-direction: column;
    gap: 18px;
  }

  .path-list li {
    grid-template-columns: 44px minmax(0, 1fr);
  }

  .module-grid,
  .question-list {
    grid-template-columns: minmax(0, 1fr);
  }

  .modules {
    padding-inline: 18px;
    border-radius: 8px 8px 44px 8px;
  }

  .hero-actions a {
    width: 100%;
    text-align: center;
  }
}