@import url('https://fonts.googleapis.com/css2?family=Bebas+Neue&family=Source+Sans+3:wght@300;400;500;600;700&display=swap');

:root {
  --mint: #b4fde1;
  --blue: #add8e6;
  --ink: #172620;
  --mint-soft: #ddfff2;
  --blue-soft: #dcf0f7;
  --paper: #effbf6;
  --out: 6px 7px 16px rgba(23, 38, 32, 0.15);
  --in: inset -3px -3px 9px rgba(23, 38, 32, 0.1), inset 3px 3px 9px rgba(255, 255, 255, 0.85);
  --r: 18px;
  --r-lg: 24px;
  --font: "Source Sans 3", -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

*,
*::before,
*::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.75;
  color: var(--ink);
  background:
    radial-gradient(1100px 560px at 82% -8%, var(--blue-soft), transparent 62%),
    radial-gradient(820px 480px at 8% 2%, var(--mint-soft), transparent 58%),
    var(--paper);
  overflow-x: hidden;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }
h1, h2, h3 { letter-spacing: 0.01em; }

:focus-visible {
  outline: 3px solid #0f6a51;
  outline-offset: 3px;
}

/* ---------- 顶部 ---------- */
.top {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 14px;
  padding: 10px 18px;
  background: rgba(239, 251, 246, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 3px solid rgba(23, 38, 32, 0.85);
}

.logo {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  flex: 0 0 auto;
  border-radius: 16px;
  background: linear-gradient(150deg, var(--mint), var(--blue));
  border: 3px solid var(--ink);
  box-shadow: var(--in), 3px 4px 0 rgba(23, 38, 32, 0.8);
  text-decoration: none;
  transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.logo:hover { transform: translateY(-2px) rotate(-4deg); }
.logo:active { transform: translateY(2px); }

.logo-img {
  width: 28px;
  height: 28px;
  border-radius: 8px;
  object-fit: contain;
}

.logo-txt {
  font-size: 20px;
  font-weight: 700;
  line-height: 1;
}

.top nav { min-width: 0; }

.top nav p {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  justify-content: flex-end;
}

.top nav a {
  display: inline-flex;
  align-items: center;
  min-height: 42px;
  padding: 6px 14px;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  border-radius: 999px;
  border: 3px solid var(--ink);
  background: linear-gradient(160deg, #ffffff, var(--mint));
  box-shadow: var(--in), 3px 3px 0 rgba(23, 38, 32, 0.78);
  transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.2s ease-out, background 0.2s ease-out;
}

.top nav a:hover {
  transform: translateY(-3px);
  background: linear-gradient(160deg, #ffffff, var(--blue));
}

.top nav a:active {
  transform: translateY(2px);
  box-shadow: var(--in), 1px 1px 0 rgba(23, 38, 32, 0.7);
}

/* ---------- 首屏 ---------- */
.hero {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 45vh;
  padding: 26px 18px 34px;
  overflow: hidden;
  text-align: center;
}

.ghost {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-family: "Bebas Neue", var(--font);
  font-size: clamp(56px, 15vw, 168px);
  line-height: 0.9;
  letter-spacing: 0.08em;
  color: rgba(23, 38, 32, 0.075);
  white-space: nowrap;
  pointer-events: none;
  user-select: none;
  will-change: transform;
}

.hero h1 {
  position: relative;
  margin: 0;
  max-width: 22ch;
  font-size: clamp(31px, 7.4vw, 62px);
  line-height: 1.14;
  font-weight: 700;
  animation: rise 0.55s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

.lead {
  position: relative;
  margin: 14px auto 0;
  max-width: 40ch;
  font-size: 16.5px;
  line-height: 1.7;
  color: rgba(23, 38, 32, 0.78);
  animation: rise 0.55s cubic-bezier(0.34, 1.56, 0.64, 1) 0.08s both;
}

@keyframes rise {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: none; }
}

/* ---------- 版心 ---------- */
.wrap {
  display: grid;
  grid-template-columns: 246px minmax(0, 1fr);
  gap: 26px;
  align-items: start;
  max-width: 1120px;
  margin: 0 auto;
  padding: 16px 18px 64px;
}

.side {
  position: sticky;
  top: 88px;
  padding: 16px 14px 18px;
  border: 3px solid var(--ink);
  border-radius: var(--r-lg);
  background: linear-gradient(165deg, #ffffff, var(--mint));
  box-shadow: var(--in), var(--out);
}

.side h2 {
  margin: 0 0 4px;
  font-size: 19px;
  line-height: 1.35;
}

.side .subtitle {
  margin: 0 0 12px;
  font-size: 15px;
  letter-spacing: 0.05em;
  color: rgba(23, 38, 32, 0.62);
}

.side ul {
  display: grid;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.side a {
  display: flex;
  align-items: center;
  min-height: 42px;
  padding: 6px 12px;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  border-radius: 14px;
  border: 2px solid rgba(23, 38, 32, 0.75);
  background: rgba(255, 255, 255, 0.72);
  box-shadow: inset -2px -2px 6px rgba(23, 38, 32, 0.08);
  transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1), background 0.2s ease-out;
}

.side a:hover {
  background: #ffffff;
  transform: translateX(3px);
}

.side a:active { transform: translateX(1px) scale(0.99); }

/* ---------- 正文 ---------- */
.prose {
  display: grid;
  gap: 18px;
  max-width: 780px;
}

.prose > div {
  padding: 22px 22px 26px;
  border-radius: var(--r);
  background: linear-gradient(160deg, #ffffff, var(--mint-soft));
  scroll-margin-top: 120px;
  box-shadow: 2px 3px 0 rgba(23, 38, 32, 0.06);
}

.prose > div:nth-child(even) {
  background: linear-gradient(160deg, #ffffff, var(--blue-soft));
}

.prose h2 {
  margin: 0 0 12px;
  font-size: clamp(22px, 3.3vw, 30px);
  line-height: 1.28;
}

.prose h3 {
  margin: 22px 0 8px;
  font-size: 19px;
  line-height: 1.4;
}

.prose h2 + .subtitle,
.prose h2 + .subhead,
.prose h2 + .lead {
  margin-top: -6px;
  font-weight: 600;
  color: rgba(23, 38, 32, 0.7);
}

.prose p { margin: 0 0 14px; }
.prose p:last-child { margin-bottom: 0; }

.prose ul,
.prose ol {
  margin: 0 0 14px;
  padding-left: 1.25em;
}

.prose li { margin: 6px 0; }

.prose a {
  color: #0d5c46;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.prose a:hover { color: #08382b; }

.prose blockquote {
  margin: 0 0 14px;
  padding: 12px 16px;
  border-radius: 14px;
  border-left: 5px solid var(--ink);
  background: rgba(173, 216, 230, 0.4);
}

.prose img {
  margin: 12px 0;
  border-radius: 14px;
}

.prose code {
  padding: 1px 6px;
  border-radius: 8px;
  background: rgba(23, 38, 32, 0.08);
  font-size: 15px;
}

/* ---------- 页脚 ---------- */
footer {
  margin-top: 18px;
  padding: 44px 18px 22px;
  border-radius: 36px 36px 0 0;
  background: var(--ink);
  color: var(--mint);
}

.f-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 24px 20px;
  max-width: 1120px;
  margin: 0 auto;
}

.f-brand {
  margin: 0;
  font-size: clamp(29px, 4.6vw, 50px);
  font-weight: 800;
  line-height: 1.06;
  letter-spacing: 0.02em;
  color: #ffffff;
}

footer dl { margin: 0; }

footer dt {
  margin-bottom: 10px;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--blue);
}

footer dd {
  margin: 0 0 6px;
  font-size: 16px;
}

footer dd a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  text-decoration: none;
  color: var(--mint);
  transition: transform 0.2s ease-out, color 0.2s ease-out;
}

footer dd a:hover {
  color: #ffffff;
  transform: translateX(3px);
}

.f-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  max-width: 1120px;
  margin: 28px auto 0;
  padding-top: 14px;
  border-top: 2px solid rgba(180, 253, 225, 0.28);
  font-size: 15px;
}

.cr { margin: 0; color: rgba(180, 253, 225, 0.78); }
.to-top { margin: 0; }

.to-top a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 16px;
  border-radius: 999px;
  border: 3px solid var(--mint);
  background: var(--mint);
  color: var(--ink);
  font-weight: 700;
  text-decoration: none;
  transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.to-top a:hover { transform: translateY(-3px); }
.to-top a:active { transform: translateY(1px); }

/* ---------- 自适应 ---------- */
@media (max-width: 900px) {
  .wrap {
    grid-template-columns: minmax(0, 1fr);
    gap: 18px;
    padding-top: 12px;
  }

  .side { position: static; }

  .side ul {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
  }

  .side a { padding: 6px 12px; }

  .prose { max-width: none; }

  .f-grid { grid-template-columns: 1fr 1fr; }
  .f-brand { grid-column: 1 / -1; }
}

@media (max-width: 860px) {
  .top { position: static; }
  .prose > div { scroll-margin-top: 24px; }
}

@media (max-width: 600px) {
  body { font-size: 16.5px; }

  .top { padding: 10px 14px; }

  .top nav p { justify-content: flex-start; }

  .top nav a {
    padding: 6px 11px;
    font-size: 15.5px;
    min-height: 40px;
  }

  .hero {
    min-height: 42vh;
    padding: 18px 14px 26px;
  }

  .wrap { padding: 12px 14px 48px; }

  .prose > div { padding: 18px 16px 20px; }

  footer { padding: 34px 14px 20px; border-radius: 26px 26px 0 0; }

  .f-grid { grid-template-columns: 1fr; gap: 18px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}

button[aria-expanded]{min-width:44px;min-height:44px}