@import url("fonts/fonts.css");

/* ── tokens ────────────────────────────────────────────────────────────
   取自 TerraForge 应用自身的暗色主题（static/css/style.css）：
   ink 系是 --color-bg-*，paper 系是 --color-text-*，sky 是 --color-accent。
   ramp 八档是等高线默认分层设色配色（contourTintPalette），页面上作为
   真实高程图例使用，不当装饰色。
   ------------------------------------------------------------------- */
:root {
  --ink:        #0c0d10;
  --ink-1:      #101217;
  --ink-2:      #161920;
  --line:       rgba(232, 234, 237, .10);
  --line-hi:    rgba(232, 234, 237, .20);

  --paper:      #e8eaed;
  --paper-2:    #9aa3ad;
  --paper-3:    #6b7480;

  --sky:        #38bdf8;
  --sky-hi:     #7dd3fc;
  --sky-dim:    rgba(56, 189, 248, .12);
  --sky-glow:   rgba(56, 189, 248, .55);
  --sky-ink:    #041e2b;

  --amber:      #dcd98e;

  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
          "HarmonyOS Sans SC", "Source Han Sans SC", "Noto Sans SC",
          "Microsoft YaHei", sans-serif;

  --gut: clamp(1.25rem, 4vw, 3rem);
  --max: 1180px;
}

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

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

body {
  margin: 0;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a { color: var(--sky); text-decoration: none; }
a:hover { color: var(--sky-hi); }

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

.wrap { width: 100%; max-width: var(--max); margin-inline: auto; padding-inline: var(--gut); }

.mono {
  font-family: var(--mono);
  font-feature-settings: "tnum" 1;
}

/* eyebrow ─ 小写 latin 标签，全站唯一的「仪表盘」声音 */
.eyebrow {
  font-family: var(--mono);
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--paper-3);
  margin: 0 0 1rem;
}
.eyebrow b { color: var(--sky); font-weight: 600; }

.skip {
  position: absolute; left: -9999px;
  background: var(--sky); color: var(--sky-ink);
  padding: .6rem 1rem; font-weight: 600; z-index: 99;
}
.skip:focus { left: var(--gut); top: .5rem; }

/* 粘顶导航会盖住锚点目标，给所有带 id 的区块留出让位 */
[id] { scroll-margin-top: 76px; }

/* ── masthead ──────────────────────────────────────────────────────── */
.masthead {
  position: sticky; top: 0; z-index: 50;
  background: rgba(12, 13, 16, .82);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.masthead .wrap {
  display: flex; align-items: center; gap: 1.5rem;
  height: 60px;
}
.wordmark {
  font-family: var(--mono);
  font-size: .92rem; font-weight: 700; letter-spacing: .14em;
  color: var(--paper); white-space: nowrap;
}
.wordmark span { color: var(--sky); }
.masthead nav { margin-left: auto; display: flex; align-items: center; gap: clamp(.9rem, 2.5vw, 1.9rem); }
.masthead nav a {
  position: relative;
  font-size: .875rem; color: var(--paper-2);
  padding-bottom: 3px;
  transition: color .2s ease;
}
/* 下划线从左侧生长，而不是整条一起出现 —— 用伪元素才能 scaleX，
   border-bottom 做不到（它只能整条切换颜色）。 */
.masthead nav a::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: 0; height: 1px;
  background: var(--sky); transform: scaleX(0); transform-origin: left;
  transition: transform .28s cubic-bezier(.22, 1, .36, 1);
}
.masthead nav a:hover { color: var(--paper); }
.masthead nav a:hover::after,
.masthead nav a:focus-visible::after { transform: scaleX(1); }
.masthead nav a.ext { font-family: var(--mono); font-size: .8rem; letter-spacing: .04em; }
@media (max-width: 560px) { .masthead nav a.hide-sm { display: none; } }

/* ── hero ──────────────────────────────────────────────────────────── */
.hero { padding: clamp(3.5rem, 9vw, 7rem) 0 clamp(2.5rem, 5vw, 3.5rem); }

/* 首屏 eyebrow 就是下方那张图里选区的真实四至 */
.coords {
  display: flex; flex-wrap: wrap; gap: .35rem 1.15rem;
  font-family: var(--mono); font-size: .76rem; letter-spacing: .06em;
  color: var(--paper-3); margin: 0 0 1.6rem;
}
.coords b { color: var(--paper-2); font-weight: 400; }
.coords em { font-style: normal; color: var(--sky); }

h1 {
  margin: 0 0 1.4rem;
  font-size: clamp(2.1rem, 5.4vw, 4.1rem);
  font-weight: 700; line-height: 1.12; letter-spacing: -.02em;
  text-wrap: balance;
}
/* 标题固定在逗号处断行。CJK 逐字回绕会把「把/它」这类词劈开，text-wrap: balance
   管不到标点，只能显式给一个断点；窄到放不下时仍会自然回绕。 */
.lede {
  margin: 0 0 2.2rem; max-width: 58ch;
  font-size: clamp(1rem, 1.35vw, 1.14rem);
  line-height: 1.85; color: var(--paper-2);
}

.cta { display: flex; flex-wrap: wrap; gap: .75rem; margin-bottom: 1.5rem; }
.btn {
  display: inline-flex; align-items: center; gap: .5rem;
  padding: .72rem 1.4rem; border-radius: 3px;
  font-size: .93rem; font-weight: 600; line-height: 1.4;
  border: 1px solid transparent;
  transition: background .18s ease, border-color .18s ease, color .18s ease,
              box-shadow .22s ease, transform .18s cubic-bezier(.22, 1, .36, 1);
}
.btn:hover { transform: translateY(-2px); }
/* 按下时落回原位，且快得多 —— 抬起要缓、落下要脆，否则点击没有手感 */
.btn:active { transform: translateY(0); transition-duration: .05s; }
.btn-solid { background: var(--sky); color: var(--sky-ink); }
.btn-solid:hover { background: var(--sky-hi); box-shadow: 0 10px 26px -12px var(--sky-glow); }
.btn-ghost { border-color: var(--line-hi); color: var(--paper); }
.btn-ghost:hover { border-color: var(--sky); color: var(--sky); background: var(--sky-dim); }
.btn .v { font-family: var(--mono); font-size: .85rem; letter-spacing: .02em; }

.hero-meta {
  font-family: var(--mono); font-size: .76rem; letter-spacing: .04em;
  color: var(--paper-3); margin: 0;
}

/* ── hero shot + 高程图例（签名元素）───────────────────────────────── */
.shot-hero { margin: 0; padding-inline: var(--gut); }
.shot-hero img {
  width: 100%; max-width: 1520px; margin-inline: auto;
  /* 首屏图铺满宽度时会高到吃掉整屏，压到 68vh 让下面的高程图例进入视野。
     裁掉的是地图边缘，对内容没有损失。 */
  max-height: 68vh; object-fit: cover; object-position: center 42%;
  border: 1px solid var(--line); border-bottom: 0;
  background: var(--ink-1);
}

/* 图例必须和上面那张图等宽：两者都是「先留 gut 内边距，再限 1520」 */
.legend { margin: 0 0 clamp(4rem, 8vw, 6.5rem); padding-inline: var(--gut); }
.legend-inner { max-width: 1520px; margin-inline: auto; }
.legend-ramp { display: flex; height: 7px; }
.legend-ramp i { flex: 1; display: block; }
.legend-scale {
  display: flex; margin-top: .45rem;
  font-family: var(--mono); font-size: .64rem; letter-spacing: .05em; color: var(--paper-3);
}
.legend-scale i { flex: 1; font-style: normal; }
.legend-cap {
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: .5rem 1.5rem;
  margin-top: .9rem;
  font-family: var(--mono); font-size: .7rem; letter-spacing: .05em; color: var(--paper-3);
}
@media (max-width: 620px) { .legend-scale i:nth-child(even) { color: transparent; } }

/* ── generic band ──────────────────────────────────────────────────── */
.band { padding-block: clamp(3.5rem, 8vw, 6rem); border-top: 1px solid var(--line); }
.band-head { max-width: 62ch; margin-bottom: clamp(2.5rem, 5vw, 3.75rem); }
.band-head h2 {
  margin: 0 0 .9rem;
  font-size: clamp(1.55rem, 3vw, 2.3rem); font-weight: 700;
  line-height: 1.25; letter-spacing: -.015em;
}
.band-head p { margin: 0; color: var(--paper-2); font-size: 1.02rem; }

/* ── pipelines ─────────────────────────────────────────────────────── */
.pipe { display: grid; gap: clamp(1.75rem, 4vw, 3.25rem); align-items: start; }
.pipe + .pipe { margin-top: clamp(3.5rem, 7vw, 5.5rem); padding-top: clamp(3.5rem, 7vw, 5.5rem); border-top: 1px solid var(--line); }
@media (min-width: 900px) {
  .pipe { grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr); }
  .pipe.flip .pipe-text { order: 2; }
}
.pipe h3 {
  margin: 0 0 1rem;
  font-size: clamp(1.3rem, 2.2vw, 1.72rem); font-weight: 650;
  line-height: 1.4; letter-spacing: -.01em;
}
.pipe p { margin: 0 0 1.5rem; color: var(--paper-2); }

/* spec = 真实参数键值对，用等宽标签排成仪表盘 */
.spec { margin: 0; display: grid; gap: .7rem; }
.spec > div {
  display: grid; grid-template-columns: 5.5rem minmax(0, 1fr); gap: .9rem;
  padding-top: .7rem; border-top: 1px solid var(--line);
  font-size: .89rem; line-height: 1.65;
}
.spec dt {
  font-family: var(--mono); font-size: .7rem; font-weight: 600;
  letter-spacing: .12em; text-transform: uppercase;
  color: var(--paper-3); padding-top: .28rem;
}
.spec dd { margin: 0; color: var(--paper-2); }
.spec dd code {
  font-family: var(--mono); font-size: .86em; color: var(--paper);
  background: var(--ink-2); padding: .05em .38em; border-radius: 2px;
}
@media (max-width: 420px) { .spec > div { grid-template-columns: 1fr; gap: .2rem; } }

.shot {
  margin: 0; border: 1px solid var(--line); background: var(--ink-1);
  overflow: hidden;
}
.shot img { width: 100%; }
.shot figcaption {
  font-family: var(--mono); font-size: .68rem; letter-spacing: .05em;
  color: var(--paper-3); padding: .6rem .85rem; border-top: 1px solid var(--line);
}

/* ── claims ────────────────────────────────────────────────────────── */
.claims { display: grid; gap: 1px; background: var(--line); border: 1px solid var(--line); }
@media (min-width: 760px) { .claims { grid-template-columns: 1fr 1fr; } }
.claim { background: var(--ink); padding: clamp(1.5rem, 3vw, 2.1rem); }
.claim h3 {
  margin: 0 0 .7rem; font-size: 1.06rem; font-weight: 650; letter-spacing: -.005em;
}
.claim p { margin: 0; color: var(--paper-2); font-size: .93rem; line-height: 1.8; }
.claim p code {
  font-family: var(--mono); font-size: .86em; color: var(--paper);
  background: var(--ink-2); padding: .05em .38em; border-radius: 2px;
}

/* 工程一节只挂一张配置面板图：纵向截图铺满宽度会失真，限宽居中 */
.shot.solo { max-width: 480px; margin: clamp(2.5rem, 5vw, 3.5rem) auto 0; }

/* ── download ──────────────────────────────────────────────────────── */
.plats { display: grid; gap: 1px; background: var(--line); border: 1px solid var(--line); }
@media (min-width: 820px) { .plats { grid-template-columns: repeat(3, 1fr); } }
.plat {
  position: relative; overflow: hidden;
  background: var(--ink); padding: clamp(1.4rem, 3vw, 1.9rem);
  display: flex; flex-direction: column; gap: .55rem;
  transition: background .2s ease;
}
/* 左侧色条从下往上长出来 —— 卡片是链接，需要一个比变底色更明确的「选中」信号 */
.plat::before {
  content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 2px;
  background: var(--sky); transform: scaleY(0); transform-origin: bottom;
  transition: transform .3s cubic-bezier(.22, 1, .36, 1);
}
.plat:hover, .plat:focus-visible { background: var(--ink-1); }
.plat:hover::before, .plat:focus-visible::before { transform: scaleY(1); }
.plat-os { font-size: 1.12rem; font-weight: 650; color: var(--paper); }
.plat-arch { font-family: var(--mono); font-size: .74rem; letter-spacing: .06em; color: var(--paper-3); }
.plat-file {
  font-family: var(--mono); font-size: .76rem; color: var(--sky);
  word-break: break-all; margin-top: auto; padding-top: .8rem;
  transition: color .2s ease, transform .3s cubic-bezier(.22, 1, .36, 1);
}
.plat:hover .plat-file,
.plat:focus-visible .plat-file { color: var(--sky-hi); transform: translateX(4px); }

.notes { margin: clamp(2rem, 4vw, 2.75rem) 0 0; padding: 0; list-style: none; display: grid; gap: .95rem; }
.notes li {
  padding-left: 1.6rem; position: relative;
  font-size: .92rem; line-height: 1.75; color: var(--paper-2);
}
.notes li::before {
  content: "—"; position: absolute; left: 0; top: 0;
  font-family: var(--mono); color: var(--paper-3);
}
.notes li code {
  font-family: var(--mono); font-size: .86em; color: var(--paper);
  background: var(--ink-2); padding: .05em .38em; border-radius: 2px;
}
.notes li.warn { color: var(--paper); }
.notes li.warn::before { content: "!"; color: var(--amber); font-weight: 700; }
.notes li.warn strong { color: var(--amber); font-weight: 600; }

.tail { margin-top: 2rem; font-family: var(--mono); font-size: .8rem; display: flex; flex-wrap: wrap; gap: .5rem 1.4rem; }

/* ── docs ──────────────────────────────────────────────────────────── */
.docs { display: grid; gap: 1px; background: var(--line); border: 1px solid var(--line); }
@media (min-width: 700px) { .docs { grid-template-columns: 1fr 1fr; } }
.doc {
  position: relative; overflow: hidden;
  background: var(--ink); padding: 1.35rem clamp(1.25rem, 3vw, 1.75rem);
  display: grid; gap: .3rem; transition: background .2s ease;
}
/* 与平台卡同一套语言：左侧色条 + 标题右移，保持整站交互词汇一致 */
.doc::before {
  content: ""; position: absolute; left: 0; top: 0; bottom: 0; width: 2px;
  background: var(--sky); transform: scaleY(0); transform-origin: bottom;
  transition: transform .3s cubic-bezier(.22, 1, .36, 1);
}
.doc:hover, .doc:focus-visible { background: var(--ink-1); }
.doc:hover::before, .doc:focus-visible::before { transform: scaleY(1); }
.doc-name {
  font-weight: 600; color: var(--paper); font-size: 1rem;
  transition: color .2s ease, transform .3s cubic-bezier(.22, 1, .36, 1);
}
.doc:hover .doc-name,
.doc:focus-visible .doc-name { color: var(--sky); transform: translateX(4px); }
.doc-desc { color: var(--paper-2); font-size: .88rem; line-height: 1.7; }
.doc-file { font-family: var(--mono); font-size: .7rem; letter-spacing: .04em; color: var(--paper-3); }

/* ── footer ────────────────────────────────────────────────────────── */
footer { border-top: 1px solid var(--line); padding-block: clamp(3rem, 6vw, 4.5rem) 3rem; }
.legal { display: grid; gap: 1.5rem; max-width: 76ch; }
.legal h2 { margin: 0; font-size: .72rem; font-family: var(--mono); font-weight: 600; letter-spacing: .18em; text-transform: uppercase; color: var(--paper-3); }
.legal p { margin: 0; font-size: .88rem; line-height: 1.8; color: var(--paper-2); }
.legal .cite {
  font-family: var(--mono); font-size: .8rem; color: var(--paper);
  border-left: 2px solid var(--line-hi); padding: .2rem 0 .2rem .9rem;
}
.colophon {
  margin-top: clamp(2.5rem, 5vw, 3.5rem); padding-top: 1.5rem; border-top: 1px solid var(--line);
  display: flex; flex-wrap: wrap; gap: .5rem 1.5rem; align-items: baseline;
  font-family: var(--mono); font-size: .75rem; letter-spacing: .04em; color: var(--paper-3);
}
.colophon a { color: var(--paper-2); }
.colophon a:hover { color: var(--sky); }

/* ══ 动效 ═══════════════════════════════════════════════════════════════
   全部入场动效关在 no-preference 里：开了「减少动态效果」的用户拿到的是
   一个完全静止的页面，而不是「动得慢一点」的页面。初始隐藏状态也在这个
   块里 —— 放外面的话，reduce 用户会看到一个永远 opacity:0 的空页面。

   缓动统一用 cubic-bezier(.22,1,.36,1)（easeOutQuint）：起步快、收尾稳，
   适合「东西落到位」而不是「东西弹一下」。
   ═══════════════════════════════════════════════════════════════════════ */
@media (prefers-reduced-motion: no-preference) {

  @keyframes tf-rise   { from { opacity: 0; transform: translateY(18px); } }
  @keyframes tf-settle { from { opacity: 0; transform: scale(1.03); } }
  /* to 必须写死。省略 to 时终值取元素的计算值，而色带的基础规则本身就是
     scaleX(0) —— 那样它会从 0 动到 0，肉眼看到的是色带整条消失。 */
  @keyframes tf-band   { from { transform: scaleX(0); } to { transform: scaleX(1); } }

  /* ── 首屏入场：逐级上浮，一次性编排 ───────────────────────────────
     用 animation 而不是 IntersectionObserver：首屏本来就在视口里，等
     观察器回调会晚一帧，肉眼能看出「先空一下再动」。
     backwards 填充让元素在延迟期间保持起始态，避免闪一下再消失。 */
  .hero .coords,
  .hero h1,
  .hero .lede,
  .hero .cta,
  .hero .hero-meta { animation: tf-rise .7s cubic-bezier(.22, 1, .36, 1) backwards; }
  .hero .coords    { animation-delay: .05s; }
  .hero h1         { animation-delay: .13s; }
  .hero .lede      { animation-delay: .22s; }
  .hero .cta       { animation-delay: .31s; }
  .hero .hero-meta { animation-delay: .39s; }

  /* 地图从 1.03 沉降到 1，像镜头稳下来。比淡入更贴合「这是一张地图」。 */
  .shot-hero img { animation: tf-settle .95s cubic-bezier(.22, 1, .36, 1) .30s backwards; }

  /* ── 签名动作：高程图例逐档展开 ───────────────────────────────────
     八个色块各自从左边缘长出，40ms 一档，读起来是一条分层设色图例被
     「绘制」出来 —— 全站唯一的大动作，其余一切保持克制。 */
  .legend .legend-ramp i { transform: scaleX(0); transform-origin: left; }
  .legend.in .legend-ramp i {
    animation: tf-band .42s cubic-bezier(.22, 1, .36, 1) both;
  }
  .legend.in .legend-ramp i:nth-child(1) { animation-delay: .00s; }
  .legend.in .legend-ramp i:nth-child(2) { animation-delay: .04s; }
  .legend.in .legend-ramp i:nth-child(3) { animation-delay: .08s; }
  .legend.in .legend-ramp i:nth-child(4) { animation-delay: .12s; }
  .legend.in .legend-ramp i:nth-child(5) { animation-delay: .16s; }
  .legend.in .legend-ramp i:nth-child(6) { animation-delay: .20s; }
  .legend.in .legend-ramp i:nth-child(7) { animation-delay: .24s; }
  .legend.in .legend-ramp i:nth-child(8) { animation-delay: .28s; }

  /* 刻度与说明等色带铺完再出现，否则会和色带抢注意力 */
  .legend .legend-scale,
  .legend .legend-cap { opacity: 0; transition: opacity .5s ease .42s; }
  .legend.in .legend-scale,
  .legend.in .legend-cap { opacity: 1; }

  /* ── 通用滚动揭示 ─────────────────────────────────────────────── */
  .rv {
    opacity: 0; transform: translateY(16px);
    transition: opacity .6s cubic-bezier(.22, 1, .36, 1),
                transform .6s cubic-bezier(.22, 1, .36, 1);
  }
  .rv.in { opacity: 1; transform: none; }

  /* 管线段落：文字先落位，截图晚 90ms —— 视线自然从左读到右 */
  .pipe.rv .pipe-text { transition-delay: 0s; }
  .pipe.rv > .shot { opacity: 0; transform: translateY(16px);
    transition: opacity .6s cubic-bezier(.22, 1, .36, 1) .09s,
                transform .6s cubic-bezier(.22, 1, .36, 1) .09s; }
  .pipe.rv.in > .shot { opacity: 1; transform: none; }

  /* 参数行逐条点亮，像仪表盘上电。这里错峰是有理由的：它本来就是逐行读的。 */
  .rv .spec > div {
    opacity: 0; transform: translateY(8px);
    transition: opacity .45s ease, transform .45s cubic-bezier(.22, 1, .36, 1);
  }
  .rv.in .spec > div { opacity: 1; transform: none; }
  .rv.in .spec > div:nth-child(1) { transition-delay: .14s; }
  .rv.in .spec > div:nth-child(2) { transition-delay: .20s; }
  .rv.in .spec > div:nth-child(3) { transition-delay: .26s; }
  .rv.in .spec > div:nth-child(4) { transition-delay: .32s; }

  /* 卡片网格错峰：四条主张 / 三个平台 / 四个文档入口 */
  .rv .claim,
  .rv .plat,
  .rv .doc,
  .notes.rv li {
    opacity: 0; transform: translateY(12px);
    transition: opacity .5s ease, transform .5s cubic-bezier(.22, 1, .36, 1),
                background .2s ease;
  }
  .rv.in .claim,
  .rv.in .plat,
  .rv.in .doc,
  .notes.rv.in li { opacity: 1; transform: none; }

  .rv.in .claim:nth-child(2) { transition-delay: .07s; }
  .rv.in .claim:nth-child(3) { transition-delay: .14s; }
  .rv.in .claim:nth-child(4) { transition-delay: .21s; }

  .rv.in .plat:nth-child(2) { transition-delay: .08s; }
  .rv.in .plat:nth-child(3) { transition-delay: .16s; }

  .rv.in .doc:nth-child(2) { transition-delay: .06s; }
  .rv.in .doc:nth-child(3) { transition-delay: .12s; }
  .rv.in .doc:nth-child(4) { transition-delay: .18s; }

  /* .notes 自己就带 rv 类，所以是 .notes.rv li（同一元素）而不是
     .rv .notes li（两个元素）—— 后者永远匹配不上。 */
  .notes.rv.in li:nth-child(2) { transition-delay: .04s; }
  .notes.rv.in li:nth-child(3) { transition-delay: .08s; }
  .notes.rv.in li:nth-child(4) { transition-delay: .12s; }
  .notes.rv.in li:nth-child(5) { transition-delay: .16s; }
  .notes.rv.in li:nth-child(6) { transition-delay: .20s; }
  .notes.rv.in li:nth-child(7) { transition-delay: .24s; }
}

/* 兜底：即使上面漏了什么，reduce 用户也不会看到任何动效。 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-delay: 0ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    transition-delay: 0ms !important;
  }
}