:root {
  --ink: #17231d;
  --muted: #647067;
  --paper: #f5f7f4;
  --lime: #b9d937;
  --coral: #ff725e;
  --line: #d9dfd8;
  --max-width: 1280px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Inter, "Noto Sans SC", "Microsoft YaHei", sans-serif;
  line-height: 1.5;
}

button, a { font: inherit; }
a { color: inherit; text-decoration: none; }

.site-header {
  align-items: center;
  display: flex;
  justify-content: space-between;
  margin: 0 auto;
  max-width: var(--max-width);
  padding: 28px 40px;
}

.brand {
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 0;
}

.brand span { color: var(--coral); }

.site-nav { display: flex; gap: 30px; }
.site-nav a {
  color: var(--muted);
  font-size: 14px;
  transition: color 180ms ease;
}
.site-nav a:hover, .site-nav a:focus-visible { color: var(--ink); }

.menu-toggle { display: none; }

.hero {
  display: grid;
  gap: clamp(32px, 7vw, 96px);
  grid-template-columns: minmax(300px, 0.9fr) minmax(380px, 1.1fr);
  margin: 12px auto 0;
  max-width: var(--max-width);
  min-height: 610px;
  padding: 52px 40px 72px;
}

.hero-copy {
  align-self: center;
  padding-bottom: 22px;
}

.eyebrow {
  align-items: center;
  color: var(--muted);
  display: flex;
  font-size: 12px;
  font-weight: 700;
  gap: 10px;
  letter-spacing: 1.4px;
  margin: 0 0 30px;
}

.eyebrow span {
  background: var(--coral);
  border-radius: 50%;
  display: inline-block;
  height: 8px;
  width: 8px;
}

h1, h2, h3, p { margin-top: 0; }

h1 {
  font-size: clamp(58px, 7.8vw, 112px);
  font-weight: 800;
  letter-spacing: 0;
  line-height: 1.02;
  margin-bottom: 30px;
}

h1 em {
  color: var(--coral);
  font-family: Georgia, "Noto Serif SC", serif;
  font-size: 0.74em;
  font-style: italic;
  font-weight: 400;
}

.intro {
  color: var(--muted);
  font-size: 17px;
  max-width: 315px;
}

.text-link {
  border-bottom: 1px solid var(--ink);
  display: inline-flex;
  font-size: 14px;
  font-weight: 700;
  gap: 20px;
  margin-top: 30px;
  padding-bottom: 7px;
}

.hero-visual {
  min-height: 510px;
  overflow: hidden;
  position: relative;
}

.hero-visual::before {
  background: var(--lime);
  content: "";
  height: 94%;
  position: absolute;
  right: -14px;
  top: -15px;
  width: 94%;
}

.hero-visual img {
  display: block;
  filter: saturate(0.76);
  height: 100%;
  object-fit: cover;
  position: absolute;
  width: 92%;
}

.image-note {
  background: var(--ink);
  bottom: 0;
  color: white;
  font-family: Georgia, serif;
  font-size: 14px;
  padding: 13px 17px;
  position: absolute;
  right: 0;
}

.section {
  display: grid;
  gap: 64px;
  grid-template-columns: 160px minmax(0, 1fr);
  margin: 0 auto;
  max-width: var(--max-width);
  padding: 112px 40px;
}

.section-label {
  color: var(--muted);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 1.3px;
  padding-top: 12px;
}

.section h2, .contact-section h2 {
  font-size: clamp(36px, 4.5vw, 66px);
  letter-spacing: 0;
  line-height: 1.12;
  margin-bottom: 26px;
}

.body-copy {
  color: var(--muted);
  font-size: 18px;
  line-height: 1.9;
  max-width: 620px;
}

.courses-section {
  background: #e9eee8;
  display: grid;
  gap: 64px;
  grid-template-columns: 160px minmax(0, 1fr);
  margin: 0 auto;
  max-width: var(--max-width);
  padding: 112px 40px 124px;
}

.courses-content { min-width: 0; }
.courses-heading {
  align-items: end;
  display: flex;
  gap: 50px;
  justify-content: space-between;
  margin-bottom: 58px;
}
.courses-heading h2 { margin-bottom: 0; }
.courses-heading h2 em {
  color: var(--coral);
  font-family: Georgia, "Noto Serif SC", serif;
  font-size: 0.8em;
  font-style: italic;
  font-weight: 400;
}
.courses-intro {
  color: var(--muted);
  font-size: 16px;
  line-height: 1.8;
  margin: 0 0 4px;
  max-width: 340px;
}
.course-grid {
  display: grid;
  gap: 1px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}
.course-card {
  background: var(--paper);
  display: flex;
  flex-direction: column;
  min-height: 245px;
  padding: 27px 28px 25px;
}
.course-card-featured {
  background: var(--ink);
  color: white;
}
.course-meta {
  color: var(--muted);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 1.2px;
  margin-bottom: 25px;
}
.course-card-featured .course-meta { color: #b7c1ba; }
.course-card h3 { font-size: 23px; margin-bottom: 12px; }
.course-card > p:not(.course-meta) {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.75;
  margin-bottom: 25px;
}
.course-card-featured > p:not(.course-meta) { color: #c5cec8; }
.course-link {
  border-bottom: 1px solid currentColor;
  font-size: 13px;
  font-weight: 800;
  margin-top: auto;
  padding-bottom: 6px;
  width: fit-content;
}
.course-link span { font-size: 18px; font-weight: 400; margin-left: 14px; }
.course-actions { align-items: center; display: flex; gap: 18px; margin-top: auto; }
.course-actions .course-link { margin-top: 0; }
.course-repo { color: var(--muted); font-size: 12px; }
.course-repo:hover, .course-repo:focus-visible { color: var(--ink); }

.current-section {
  background: var(--ink);
  color: white;
  max-width: none;
  padding-left: max(40px, calc((100vw - var(--max-width)) / 2 + 40px));
  padding-right: max(40px, calc((100vw - var(--max-width)) / 2 + 40px));
}

.current-section .section-label { color: #b7c1ba; }
.current-content { max-width: 900px; }

.status-grid {
  border-top: 1px solid #425047;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  margin-top: 58px;
}

.status-grid article { padding: 22px 25px 10px 0; }
.status-grid article + article { border-left: 1px solid #425047; padding-left: 25px; }
.status-number { color: var(--lime); font-size: 13px; font-weight: 800; }
.status-grid h3 { font-size: 20px; margin-bottom: 9px; }
.status-grid article p:last-child { color: #c5cec8; font-size: 14px; line-height: 1.75; margin-bottom: 0; }

.contact-section {
  margin: 0 auto;
  max-width: var(--max-width);
  padding: 130px 40px 105px;
}

.contact-section h2 { margin-bottom: 38px; }

.domain-button {
  align-items: center;
  background: var(--coral);
  border: 0;
  color: var(--ink);
  cursor: pointer;
  display: inline-flex;
  font-size: clamp(25px, 3vw, 42px);
  font-weight: 800;
  gap: 30px;
  justify-content: space-between;
  padding: 16px 20px 16px 24px;
  text-align: left;
  transition: background 160ms ease, transform 160ms ease;
}

.domain-button:hover, .domain-button:focus-visible { background: var(--lime); transform: translateY(-3px); }
.copy-icon { font-size: 30px; font-weight: 400; }
.copy-feedback { color: var(--muted); font-size: 14px; margin: 14px 0 0; min-height: 1.5em; }

.site-footer {
  border-top: 1px solid var(--line);
  color: var(--muted);
  display: flex;
  font-size: 12px;
  justify-content: space-between;
  margin: 0 auto;
  max-width: var(--max-width);
  padding: 26px 40px;
}
.site-footer p { margin: 0; }

.sr-only {
  height: 1px;
  margin: -1px;
  overflow: hidden;
  position: absolute;
  width: 1px;
  clip: rect(0, 0, 0, 0);
}

@media (max-width: 700px) {
  .site-header { padding: 22px 22px; }
  .menu-toggle {
    background: none;
    border: 0;
    cursor: pointer;
    display: grid;
    gap: 5px;
    padding: 8px 0 8px 8px;
  }
  .menu-toggle span:not(.sr-only) { background: var(--ink); display: block; height: 2px; width: 22px; }
  .site-nav {
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    display: none;
    flex-direction: column;
    gap: 0;
    left: 0;
    padding: 12px 22px 20px;
    position: absolute;
    right: 0;
    top: 72px;
    z-index: 3;
  }
  .site-nav.is-open { display: flex; }
  .site-nav a { padding: 11px 0; }
  .hero { display: block; min-height: 0; padding: 48px 22px 74px; }
  .hero-copy { padding-bottom: 55px; }
  .hero-visual { min-height: 390px; }
  .hero-visual img { width: 94%; }
  .section { display: block; padding: 80px 22px; }
  .section-label { margin-bottom: 46px; padding: 0; }
  .courses-section { display: block; padding: 80px 22px; }
  .courses-heading { align-items: start; display: block; margin-bottom: 42px; }
  .courses-intro { margin-top: 25px; max-width: 520px; }
  .course-grid { display: block; }
  .course-card { min-height: 0; padding: 25px 22px; }
  .course-card + .course-card { border-top: 1px solid var(--line); }
  .current-section { padding-left: 22px; padding-right: 22px; }
  .status-grid { display: block; margin-top: 44px; }
  .status-grid article { border-bottom: 1px solid #425047; padding: 22px 0; }
  .status-grid article + article { border-left: 0; padding-left: 0; }
  .contact-section { padding: 88px 22px 72px; }
  .domain-button { max-width: 100%; width: 100%; }
  .site-footer { padding: 22px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; }
}