/* Longer Vision Technology — longervision.com
   Design: celestial-atlas. Night-indigo sky for hero & footer,
   porcelain daylight for content, starlight gold as the single accent. */

:root {
  --night: #0c1a2e;
  --night-2: #13233e;
  --ink: #1b2b45;
  --slate: #5c6e8a;
  --porcelain: #f2f4f8;
  --paper: #ffffff;
  --gold: #c28f2c;
  --gold-bright: #e8c46a;
  --hair: rgba(27, 43, 69, 0.14);
  --hair-soft: rgba(27, 43, 69, 0.08);
  --star-line: rgba(232, 196, 106, 0.34);
  --grid-line: rgba(231, 236, 244, 0.1);
  --radius: 14px;
  --font-display: "Fraunces", "Noto Serif SC", Georgia, serif;
  --font-body:
    "IBM Plex Sans", "Noto Sans SC", -apple-system, "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
}
@media (prefers-color-scheme: dark) {
  :root {
    --porcelain: #0f1f38;
    --paper: #152846;
    --ink: #e7ecf4;
    --slate: #9fb0c8;
    --gold: #e0b254;
    --hair: rgba(231, 236, 244, 0.16);
    --hair-soft: rgba(231, 236, 244, 0.09);
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }
}
body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  color: var(--ink);
  background: var(--porcelain);
  -webkit-font-smoothing: antialiased;
}
img {
  max-width: 100%;
  display: block;
}
a {
  color: inherit;
}
:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
  border-radius: 2px;
}

.wrap {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 28px;
}

/* ---------- header ---------- */
.site-head {
  position: absolute;
  inset: 0 0 auto 0;
  z-index: 5;
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1100px;
  margin: 0 auto;
  padding: 26px 28px;
}
.wordmark {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.18em;
  color: #e7ecf4;
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 10px;
}
.wordmark b {
  font-weight: 500;
  color: var(--gold-bright);
}
.lang-switch {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: #b9c6db;
  text-decoration: none;
  border: 1px solid rgba(231, 236, 244, 0.28);
  border-radius: 999px;
  padding: 6px 16px;
}
.lang-switch:hover {
  color: #fff;
  border-color: var(--gold-bright);
}

/* ---------- hero ---------- */
.hero {
  background:
    radial-gradient(1100px 540px at 78% 18%, #16294a 0%, transparent 62%),
    var(--night);
  color: #e7ecf4;
  position: relative;
  overflow: hidden;
}
.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 40px;
  align-items: center;
  max-width: 1100px;
  margin: 0 auto;
  padding: 140px 28px 96px;
}
.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--gold-bright);
  margin: 0 0 22px;
}
.hero h1 {
  font-family: var(--font-display);
  font-weight: 550;
  font-size: clamp(38px, 5vw, 58px);
  line-height: 1.14;
  letter-spacing: 0.005em;
  margin: 0 0 24px;
  color: #f4f7fb;
}
.hero p.lede {
  font-size: 18px;
  line-height: 1.85;
  color: #b9c6db;
  max-width: 34em;
  margin: 0 0 34px;
}
.hero-cta {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--night);
  background: var(--gold-bright);
  text-decoration: none;
  padding: 13px 26px;
  border-radius: 999px;
}
.hero-cta:hover {
  background: #f2d488;
}
.hero-cta.ghost {
  background: transparent;
  color: #d7dfec;
  border: 1px solid rgba(231, 236, 244, 0.3);
  margin-left: 12px;
}
.hero-cta.ghost:hover {
  border-color: var(--gold-bright);
  color: #fff;
}

/* constellation */
.sky {
  width: 100%;
  height: auto;
}
.sky .grid {
  stroke: var(--grid-line);
  fill: none;
  stroke-width: 1;
}
.sky .link-line {
  stroke: var(--star-line);
  stroke-width: 1;
}
.sky .star-core {
  fill: #eaf0f8;
}
.sky .star-core.gold {
  fill: var(--gold-bright);
}
.sky text {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  fill: #9fb0c8;
}
.sky text.bright {
  fill: var(--gold-bright);
}
.sky a {
  cursor: pointer;
}
.sky a:hover .star-core {
  fill: #fff;
}
.sky a:hover text {
  fill: #e7ecf4;
}
.sky .dust {
  fill: #8fa3c2;
}
@keyframes twinkle {
  0%,
  100% {
    opacity: 0.25;
  }
  50% {
    opacity: 0.9;
  }
}
@media (prefers-reduced-motion: no-preference) {
  .sky .dust {
    animation: twinkle 2.6s ease-in-out infinite;
  }
  .sky .dust:nth-child(2n) {
    animation-delay: 0.9s;
  }
  .sky .dust:nth-child(3n) {
    animation-delay: 1.6s;
  }
}

/* ---------- sections ---------- */
section {
  padding: 96px 0;
}
.sec-head {
  margin: 0 0 52px;
}
.kicker {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--gold);
  margin: 0 0 14px;
}
h2 {
  font-family: var(--font-display);
  font-weight: 550;
  font-size: clamp(28px, 3.4vw, 38px);
  line-height: 1.2;
  margin: 0;
}
.sec-head p {
  color: var(--slate);
  max-width: 42em;
  margin: 16px 0 0;
}

/* pillars */
.pillars {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
}
.pillar {
  padding: 8px 36px 8px 0;
  border-left: 1px solid var(--hair);
  padding-left: 28px;
}
.pillar:first-child {
  border-left: none;
  padding-left: 0;
}
.pillar h3 {
  font-family: var(--font-display);
  font-weight: 550;
  font-size: 21px;
  margin: 0 0 12px;
}
.pillar p {
  color: var(--slate);
  font-size: 15.5px;
  margin: 0;
}
.pillar .glyph {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--gold);
  display: block;
  margin-bottom: 16px;
}

/* constellation cards */
.bg-paper {
  background: var(--paper);
}
.charts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 22px;
}
.chart-card {
  position: relative;
  display: block;
  text-decoration: none;
  border: 1px solid var(--hair);
  border-radius: var(--radius);
  padding: 28px 30px 26px;
  background: var(--porcelain);
  transition:
    border-color 0.2s,
    transform 0.2s;
}
.chart-card:hover {
  border-color: var(--gold);
  transform: translateY(-2px);
}
.chart-card .cat {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--slate);
  margin-bottom: 14px;
}
.chart-card .cat .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #3fa776;
  flex: none;
}
.chart-card h3 {
  font-family: var(--font-display);
  font-weight: 550;
  font-size: 22px;
  margin: 0 0 8px;
}
.chart-card .domain {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--gold);
  margin: 0 0 14px;
}
.chart-card p.desc {
  color: var(--slate);
  font-size: 15.5px;
  margin: 0;
}
.chart-card .go {
  position: absolute;
  top: 26px;
  right: 26px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--slate);
}
.chart-card:hover .go {
  color: var(--gold);
}

.affiliates {
  margin-top: 48px;
  padding-top: 34px;
  border-top: 1px solid var(--hair);
}
.affiliates h4 {
  font-family: var(--font-mono);
  font-weight: 400;
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--slate);
  margin: 0 0 18px;
}
.affiliates ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 28px;
}
.affiliates a {
  font-size: 15px;
  color: var(--slate);
  text-decoration: none;
  border-bottom: 1px solid var(--hair);
}
.affiliates a:hover {
  color: var(--gold);
  border-color: var(--gold);
}

/* journey */
.journey {
  position: relative;
}
.route {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 26px;
  position: relative;
}
.route::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 64px;
  height: 1px;
  background: repeating-linear-gradient(
    90deg,
    var(--gold) 0 6px,
    transparent 6px 14px
  );
  opacity: 0.55;
}
.stop {
  position: relative;
  text-align: left;
}
.stop .lens {
  width: 128px;
  height: 128px;
  border-radius: 50%;
  overflow: hidden;
  border: 2px solid var(--gold);
  outline: 6px solid var(--porcelain);
  position: relative;
  z-index: 1;
  margin-bottom: 20px;
}
.bg-paper .stop .lens {
  outline-color: var(--paper);
}
.stop .lens img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.stop .when {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--gold);
  margin: 0 0 6px;
}
.stop h3 {
  font-family: var(--font-display);
  font-weight: 550;
  font-size: 18px;
  margin: 0 0 8px;
}
.stop p {
  font-size: 14.5px;
  color: var(--slate);
  margin: 0;
  line-height: 1.65;
}

/* footer / contact */
.deep {
  background:
    radial-gradient(900px 420px at 22% 0%, #16294a 0%, transparent 60%),
    var(--night);
  color: #e7ecf4;
}
.deep .kicker {
  color: var(--gold-bright);
}
.deep h2 {
  color: #f4f7fb;
}
.contact-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 56px;
  align-items: start;
}
.deep p {
  color: #b9c6db;
}
.code-links {
  list-style: none;
  margin: 26px 0 0;
  padding: 0;
  display: grid;
  gap: 12px;
}
.code-links a {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.04em;
  color: #d7dfec;
  text-decoration: none;
  display: flex;
  gap: 14px;
  align-items: baseline;
}
.code-links a span {
  color: var(--gold-bright);
}
.code-links a:hover {
  color: #fff;
}
.contact-card {
  border: 1px solid rgba(231, 236, 244, 0.18);
  border-radius: var(--radius);
  padding: 30px 32px;
}
.contact-card dt {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: #8fa3c2;
  margin-bottom: 4px;
}
.contact-card dd {
  margin: 0 0 20px;
  font-size: 16px;
}
.contact-card dd:last-child {
  margin-bottom: 0;
}
.contact-card a {
  color: #e7ecf4;
  text-decoration: none;
  border-bottom: 1px solid rgba(231, 236, 244, 0.3);
}
.contact-card a:hover {
  color: var(--gold-bright);
  border-color: var(--gold-bright);
}
.colophon {
  margin-top: 80px;
  padding-top: 30px;
  border-top: 1px solid rgba(231, 236, 244, 0.14);
  display: flex;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
  font-size: 13.5px;
  color: #8fa3c2;
}
.colophon a {
  color: #b9c6db;
  text-decoration: none;
}
.colophon a:hover {
  color: var(--gold-bright);
}

/* reveal */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition:
    opacity 0.7s ease,
    transform 0.7s ease;
}
.reveal.in {
  opacity: 1;
  transform: none;
}
@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* lang hint bar */
.lang-hint {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 20;
  background: var(--night-2);
  color: #e7ecf4;
  border: 1px solid rgba(231, 236, 244, 0.2);
  border-radius: 999px;
  padding: 10px 10px 10px 22px;
  display: none;
  align-items: center;
  gap: 16px;
  font-size: 14px;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.35);
}
.lang-hint.show {
  display: flex;
}
.lang-hint a {
  color: var(--gold-bright);
  text-decoration: none;
  font-weight: 500;
}
.lang-hint button {
  background: none;
  border: none;
  color: #8fa3c2;
  font-size: 18px;
  cursor: pointer;
  padding: 4px 10px;
  line-height: 1;
}

/* ---------- responsive ---------- */
@media (max-width: 920px) {
  .hero-inner {
    grid-template-columns: 1fr;
    padding-top: 120px;
  }
  .sky {
    max-width: 480px;
    margin: 0 auto;
  }
  .pillars {
    grid-template-columns: 1fr;
    gap: 36px;
  }
  .pillar {
    border-left: none;
    padding-left: 0;
    border-top: 1px solid var(--hair);
    padding-top: 30px;
  }
  .pillar:first-child {
    border-top: none;
    padding-top: 0;
  }
  .charts {
    grid-template-columns: 1fr;
  }
  .route {
    grid-template-columns: 1fr;
    gap: 40px;
    max-width: 460px;
  }
  .route::before {
    left: 63px;
    right: auto;
    top: 0;
    bottom: 0;
    width: 1px;
    height: auto;
    background: repeating-linear-gradient(
      180deg,
      var(--gold) 0 6px,
      transparent 6px 14px
    );
  }
  .stop {
    display: grid;
    grid-template-columns: 128px 1fr;
    gap: 24px;
    align-items: center;
  }
  .stop .lens {
    margin-bottom: 0;
  }
  .stop .stop-info {
    min-width: 0;
  }
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  section {
    padding: 72px 0;
  }
}
@media (max-width: 480px) {
  .stop {
    grid-template-columns: 96px 1fr;
    gap: 18px;
  }
  .stop .lens {
    width: 96px;
    height: 96px;
  }
  .route::before {
    left: 47px;
  }
  .hero-cta.ghost {
    margin-left: 0;
    margin-top: 12px;
  }
}

.wordmark-cube {
  width: 30px;
  height: 30px;
  display: block;
  flex: none;
  /* 立方体本身是透明背景的写实渲染，深色 hero 顶栏上直接可见 */
}
@media (max-width: 480px) {
  .wordmark-cube {
    width: 26px;
    height: 26px;
  }
}