@import url('https://fonts.googleapis.com/css2?family=Cormorant+Garamond:wght@400;500;600;700&family=Libre+Baskerville:wght@400;700&display=swap');

:root {
  --neon: #87ff71;
  --cyan: #01cdfe;
  --ink: #192617;
  --pink: #ff71ce;
  --violet: #b967ff;
  --text: #e6f6e4;
  --line: rgba(1, 205, 254, .26);
  --serif: "Cormorant Garamond", "Libre Baskerville", "Songti SC", "Noto Serif CJK SC", "Source Han Serif SC", Georgia, serif;
}

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

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

body {
  margin: 0;
  padding-left: 92px;
  background-color: var(--ink);
  background-image:
    radial-gradient(circle, rgba(135, 255, 113, .17) 1px, transparent 1.2px),
    radial-gradient(circle at 88% -8%, rgba(1, 205, 254, .24), transparent 52%),
    radial-gradient(circle at 4% 26%, rgba(185, 103, 255, .16), transparent 46%);
  background-size: 20px 20px, auto, auto;
  background-attachment: fixed, fixed, fixed;
  color: var(--text);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.78;
  overflow-x: hidden;
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 30;
  pointer-events: none;
  opacity: .3;
  background-image: repeating-linear-gradient(180deg, rgba(0, 0, 0, .32) 0 2px, transparent 2px 4px);
}

a { color: var(--cyan); }

img { max-width: 100%; height: auto; display: block; }

:focus-visible { outline: 2px solid var(--neon); outline-offset: 3px; }

/* 左侧固定竖栏 */
.rail {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  z-index: 40;
  width: 92px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
  border-right: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(25, 38, 23, .95), rgba(16, 26, 18, .82));
  backdrop-filter: blur(6px);
}

.mark {
  display: flex;
  align-items: center;
  min-height: 40px;
  padding: 6px 0;
  writing-mode: vertical-rl;
  text-orientation: mixed;
  letter-spacing: .4em;
  font-size: 18px;
  font-weight: 600;
  color: var(--neon);
  text-decoration: none;
  text-shadow: 0 0 16px rgba(135, 255, 113, .65);
}

.burger {
  writing-mode: vertical-rl;
  min-height: 60px;
  padding: 14px 10px;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: rgba(135, 255, 113, .06);
  color: #d6f2d4;
  font: inherit;
  font-size: 16px;
  letter-spacing: .32em;
  cursor: pointer;
  transition: background .2s, color .2s, box-shadow .2s;
}

.burger:hover {
  background: var(--neon);
  color: var(--ink);
  box-shadow: 0 0 26px rgba(135, 255, 113, .6);
}

/* 全屏遮罩菜单 */
.overlay {
  position: fixed;
  inset: 0;
  z-index: 60;
  overflow: auto;
  padding: 68px clamp(20px, 6vw, 72px) 48px;
  background:
    radial-gradient(circle at 50% 118%, rgba(255, 113, 206, .32), transparent 58%),
    linear-gradient(180deg, #14201a, #0b140e 88%);
}

.overlay[hidden] { display: none; }

.overlay-inner { max-width: 760px; margin: 0 auto; }

.closer {
  position: fixed;
  top: 16px;
  right: 16px;
  min-height: 46px;
  padding: 0 20px;
  border: 1px solid var(--pink);
  border-radius: 4px;
  background: transparent;
  color: #ffd9f2;
  font: inherit;
  font-size: 16px;
  letter-spacing: .2em;
  cursor: pointer;
}

.closer:hover { background: var(--pink); color: var(--ink); }

.seek {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0 0 34px;
}

.seek-label {
  width: 100%;
  font-size: 16px;
  letter-spacing: .24em;
  color: var(--cyan);
}

.seek input {
  flex: 1 1 160px;
  min-height: 48px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: rgba(255, 255, 255, .06);
  color: var(--text);
  font: inherit;
  font-size: 16px;
}

.seek button {
  min-height: 48px;
  padding: 0 22px;
  border: 1px solid var(--neon);
  border-radius: 4px;
  background: rgba(135, 255, 113, .12);
  color: var(--neon);
  font: inherit;
  font-size: 16px;
  letter-spacing: .18em;
  cursor: pointer;
}

.seek button:hover { background: var(--neon); color: var(--ink); }

.menu-nav ol {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0 32px;
}

.menu-nav a {
  display: flex;
  align-items: center;
  gap: 14px;
  min-height: 52px;
  padding: 12px 4px;
  border-bottom: 1px solid rgba(1, 205, 254, .18);
  color: #eafbe8;
  font-size: clamp(1.1rem, 2.4vw, 1.6rem);
  text-decoration: none;
  transition: color .18s, transform .18s;
}

.menu-nav a:hover {
  color: var(--neon);
  transform: translateX(6px);
  text-shadow: 0 0 16px rgba(135, 255, 113, .7);
}

.num {
  font-size: 16px;
  letter-spacing: .16em;
  color: var(--cyan);
}

/* hero */
.hero {
  position: relative;
  isolation: isolate;
  min-height: 100vh;
  display: flex;
  align-items: flex-end;
  justify-content: flex-end;
  padding: 0 clamp(20px, 5vw, 64px) clamp(80px, 14vh, 150px);
  overflow: hidden;
  background: linear-gradient(168deg, #ffa0dd 0%, #ff71ce 24%, #4fc9f2 58%, #7a3bff 100%);
  clip-path: polygon(0 0, 100% 0, 100% 91%, 0 100%);
}

.hero-art {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-art img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(1.25) contrast(1.06);
}

.hero-art::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(202deg, rgba(25, 38, 23, .06), rgba(25, 38, 23, .78));
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background-image:
    radial-gradient(rgba(25, 38, 23, .3) 1px, transparent 1px),
    radial-gradient(circle at 76% 20%, rgba(255, 251, 214, .7), rgba(255, 241, 150, .26) 16%, transparent 42%);
  background-size: 16px 16px, auto;
}

.hero-copy {
  position: relative;
  z-index: 2;
  max-width: 660px;
  text-align: right;
}

.hero h1 {
  margin: 0 0 .55em;
  font-size: clamp(2rem, 6vw, 4.4rem);
  line-height: 1.14;
  color: #fffdf6;
  letter-spacing: .012em;
  text-shadow: 0 0 20px rgba(1, 205, 254, .85), 0 0 52px rgba(255, 113, 206, .65);
  animation: flicker 7s ease-in-out infinite;
}

@keyframes flicker {
  0%, 100% { text-shadow: 0 0 20px rgba(1, 205, 254, .85), 0 0 52px rgba(255, 113, 206, .65); transform: none; }
  46% { text-shadow: 0 0 16px rgba(255, 113, 206, .9), 0 0 42px rgba(135, 255, 113, .55); }
  49% { transform: translate(2px, -1px); }
  52% { transform: none; }
}

.hero-desc {
  margin: 0 0 26px auto;
  max-width: 40ch;
  font-size: 17px;
  line-height: 1.7;
  color: #f4fff1;
  text-shadow: 0 1px 10px rgba(25, 38, 23, .85);
}

.hero-jump {
  display: inline-block;
  min-height: 48px;
  padding: 12px 30px;
  border: 1px solid #14201a;
  border-radius: 4px;
  background: #14201a;
  color: var(--neon);
  font-size: 16px;
  letter-spacing: .26em;
  text-decoration: none;
  box-shadow: 0 14px 34px -18px rgba(0, 0, 0, .9);
  transition: background .2s, color .2s, box-shadow .2s;
}

.hero-jump:hover {
  background: var(--neon);
  color: var(--ink);
  box-shadow: 0 0 30px rgba(135, 255, 113, .75);
}

/* 主体 */
.stage {
  display: grid;
  grid-template-columns: minmax(150px, 200px) minmax(0, 1fr);
  gap: clamp(20px, 4vw, 54px);
  max-width: 1180px;
  margin: 0 auto;
  padding: clamp(42px, 7vw, 92px) clamp(18px, 4vw, 48px) 0;
}

.index-rail {
  position: sticky;
  top: 34px;
  align-self: start;
}

.index-rail h2 {
  margin: 0 0 .15em;
  font-size: 1.1rem;
  letter-spacing: .26em;
  color: var(--cyan);
}

.subtitle {
  margin: 0 0 1.1em;
  font-size: 16px;
  letter-spacing: .16em;
  color: rgba(230, 246, 228, .6);
}

.index-rail nav a {
  display: block;
  padding: 11px 0;
  border-bottom: 1px dashed rgba(1, 205, 254, .22);
  color: #d9eed8;
  font-size: 16px;
  text-decoration: none;
  transition: color .18s, padding-left .18s;
}

.index-rail nav a:hover {
  color: var(--neon);
  padding-left: 6px;
}

.prose {
  min-width: 0;
  counter-reset: sec;
}

.prose div {
  counter-increment: sec;
  margin: 0 0 clamp(26px, 4vw, 48px);
  padding: clamp(20px, 3vw, 40px);
  border: 1px solid rgba(1, 205, 254, .2);
  border-radius: 4px;
  background: rgba(255, 255, 255, .038);
  box-shadow: 0 22px 46px -30px rgba(1, 205, 254, .95), inset 0 0 0 1px rgba(135, 255, 113, .05);
  scroll-margin-top: 96px;
  animation: rise .7s cubic-bezier(.2, .7, .3, 1) both;
}

.prose div:nth-child(1) { animation-delay: .02s; }
.prose div:nth-child(2) { animation-delay: .08s; }
.prose div:nth-child(3) { animation-delay: .14s; }
.prose div:nth-child(4) { animation-delay: .2s; }
.prose div:nth-child(5) { animation-delay: .26s; }
.prose div:nth-child(6) { animation-delay: .32s; }
.prose div:nth-child(7) { animation-delay: .38s; }

@keyframes rise {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: none; }
}

.prose div::before {
  content: counter(sec, decimal-leading-zero);
  display: block;
  margin-bottom: .7em;
  font-family: "Libre Baskerville", var(--serif);
  font-size: 16px;
  letter-spacing: .34em;
  color: var(--cyan);
}

.prose h2 {
  margin: 0 0 .45em;
  font-size: clamp(1.4rem, 3vw, 2.1rem);
  line-height: 1.26;
  color: var(--neon);
  text-shadow: 0 0 18px rgba(135, 255, 113, .32);
}

.prose h3 {
  margin: 1.5em 0 .4em;
  font-size: 1.2rem;
  color: #d8f6d5;
}

.prose p,
.prose li {
  max-width: 70ch;
  margin: 0 0 1em;
}

.prose ul,
.prose ol { padding-left: 1.3em; }

.prose blockquote {
  margin: 1.4em 0;
  padding: 4px 0 4px 18px;
  border-left: 2px solid var(--pink);
  color: #f2e2f6;
}

.prose a {
  color: var(--cyan);
  text-underline-offset: 3px;
}

.prose a:hover { color: var(--neon); }

.prose table {
  width: 100%;
  border-collapse: collapse;
  font-size: 16px;
}

.prose th,
.prose td {
  padding: 10px 12px;
  border-bottom: 1px solid rgba(1, 205, 254, .22);
  text-align: left;
  vertical-align: top;
}

.prose th { color: var(--neon); }

.prose img { border-radius: 4px; }

/* 页脚 */
.foot {
  margin-top: clamp(50px, 8vw, 104px);
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(1, 205, 254, .07), transparent 46%), #0e1810;
}

.foot-top {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 22px;
  max-width: 1180px;
  margin: 0 auto;
  padding: clamp(30px, 5vw, 56px) clamp(18px, 4vw, 48px) 6px;
}

.foot-name {
  margin: 0;
  font-size: 1.3rem;
  letter-spacing: .18em;
  color: var(--neon);
  text-shadow: 0 0 18px rgba(135, 255, 113, .4);
}

.sub {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.sub-label {
  width: 100%;
  font-size: 16px;
  letter-spacing: .22em;
  color: var(--cyan);
}

.sub input {
  min-height: 46px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: rgba(255, 255, 255, .06);
  color: var(--text);
  font: inherit;
  font-size: 16px;
}

.sub button {
  min-height: 46px;
  padding: 0 20px;
  border: 1px solid var(--neon);
  border-radius: 4px;
  background: rgba(135, 255, 113, .12);
  color: var(--neon);
  font: inherit;
  font-size: 16px;
  letter-spacing: .2em;
  cursor: pointer;
}

.sub button:hover:enabled { background: var(--neon); color: var(--ink); }
.sub button:disabled { opacity: .7; cursor: default; }

.foot-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px 24px;
  max-width: 1180px;
  margin: 0 auto;
  padding: 14px clamp(18px, 4vw, 48px) 30px;
}

.foot-cols dt {
  font-size: 16px;
  letter-spacing: .24em;
  color: var(--cyan);
  margin-bottom: 4px;
}

.foot-cols dd { margin: 0; }

.foot-cols a {
  display: inline-block;
  min-height: 42px;
  padding: 10px 0;
  color: #cfe6cf;
  font-size: 16px;
  text-decoration: none;
  transition: color .18s, text-shadow .18s;
}

.foot-cols a:hover {
  color: var(--neon);
  text-shadow: 0 0 14px rgba(135, 255, 113, .6);
}

.foot-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 18px;
  max-width: 1180px;
  margin: 0 auto;
  padding: 12px clamp(18px, 4vw, 48px) 26px;
  border-top: 1px solid rgba(1, 205, 254, .16);
}

.copy {
  margin: 0;
  font-size: 16px;
  color: rgba(230, 246, 228, .66);
}

.bar-links { display: flex; gap: 4px; }

.bar-links a {
  display: inline-block;
  min-height: 42px;
  padding: 10px 8px;
  color: rgba(230, 246, 228, .8);
  font-size: 16px;
  text-decoration: none;
}

.bar-links a:hover { color: var(--neon); }

@media (max-width: 860px) {
  body { padding-left: 0; padding-top: 58px; }

  .rail {
    inset: 0 0 auto 0;
    width: auto;
    height: 58px;
    flex-direction: row;
    padding: 0 14px;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .mark {
    writing-mode: horizontal-tb;
    min-height: 44px;
    letter-spacing: .22em;
    font-size: 16px;
  }

  .burger {
    writing-mode: horizontal-tb;
    min-height: 44px;
    padding: 0 18px;
    letter-spacing: .2em;
  }

  .overlay { padding: 62px 18px 40px; }

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

  .menu-nav a { min-height: 50px; font-size: 1.15rem; }

  .hero {
    min-height: 72vh;
    padding: 0 20px 10vh;
    clip-path: polygon(0 0, 100% 0, 100% 95%, 0 100%);
  }

  .hero h1 { font-size: clamp(1.7rem, 8.4vw, 2.5rem); }

  .hero-desc { max-width: 32ch; }

  .stage {
    grid-template-columns: minmax(0, 1fr);
    padding-top: 34px;
  }

  .index-rail { position: static; }

  .index-rail nav { display: flex; flex-wrap: wrap; gap: 0 20px; }

  .index-rail nav a { border-bottom: 0; }

  .prose div { scroll-margin-top: 74px; }

  .prose table {
    display: block;
    overflow-x: auto;
    white-space: nowrap;
  }

  .foot-cols { grid-template-columns: minmax(0, 1fr); gap: 6px; }

  .foot-bar { flex-direction: column; align-items: flex-start; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }
}

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