/* GitHub 文件下载桥 · 设计令牌
   与主站 www.8nj1b.top 共用同一套 8pt 栅格 / 1.25 字阶 / 单一主色，
   但换一套版式：首屏更短、工作台为主、地球只留一角作为低对比呼应。 */
:root {
  --space-1: 8px; --space-2: 16px; --space-3: 24px;
  --space-4: 32px; --space-6: 48px; --space-8: 64px; --space-12: 96px;

  --fs-xs: 12px; --fs-sm: 14px; --fs-body: 16px; --fs-lg: 18px;
  --fs-h4: 20px; --fs-h3: 24px; --fs-h2: 30px; --fs-h1: 36px;

  --radius-sm: 8px; --radius-md: 12px; --radius-lg: 16px; --radius-pill: 999px;

  --color-bg: #0B1020;
  --color-surface: #121A2E;
  --color-surface-2: #17223C;
  --color-on-surface: #E8EDF8;
  --color-muted: #A7B4CC;
  --color-dim: #7E8CA8;
  --color-outline: #2A3557;
  --color-primary: #6B9BFF;
  --color-on-primary: #08132B;
  --color-primary-soft: rgba(107, 155, 255, .12);
  --color-warn: #F0C074;
  --color-warn-soft: rgba(240, 192, 116, .10);
  --color-success: #7FD1A8;
  --color-success-soft: rgba(127, 209, 168, .10);
  --color-danger: #F08A82;

  --min-tap: 44px;
  --motion-fast: 150ms; --motion-normal: 200ms; --motion-slow: 300ms;
  --easing: cubic-bezier(.4, 0, .2, 1);
  --max-width: 1160px;
  --mono: Consolas, "SFMono-Regular", "Courier New", monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 88px; }
body {
  margin: 0; min-height: 100vh;
  background:
    radial-gradient(900px 460px at 8% -6%, rgba(45, 74, 143, .22), transparent 62%),
    radial-gradient(760px 420px at 100% 4%, rgba(28, 71, 105, .18), transparent 58%),
    var(--color-bg);
  color: var(--color-on-surface);
  font-family: "Segoe UI", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  font-size: var(--fs-body); line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--color-primary); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; display: block; }
code, pre { font-family: var(--mono); }
:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 3px; border-radius: 4px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 var(--space-3); }
.muted { color: var(--color-dim); }
.skip { position: absolute; left: -9999px; top: 0; z-index: 100; background: var(--color-primary); color: var(--color-on-primary); padding: var(--space-1) var(--space-2); border-radius: var(--radius-sm); }
.skip:focus { left: var(--space-2); top: var(--space-1); }

/* ---------- Header ---------- */
.site-header {
  position: sticky; top: 0; z-index: 30;
  background: rgba(11, 16, 32, .88); backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-outline);
}
.header-inner { display: flex; align-items: center; gap: var(--space-3); min-height: 72px; }
.brand { display: inline-flex; align-items: center; gap: var(--space-1); color: var(--color-on-surface); font-weight: 600; font-size: var(--fs-lg); }
.brand:hover { text-decoration: none; }
.brand-mark {
  width: 28px; height: 28px; border-radius: var(--radius-sm); flex: none;
  background: linear-gradient(135deg, var(--color-primary), #3C6FD1); position: relative;
}
.brand-mark::after { content: ""; position: absolute; inset: 8px; border: 2px solid var(--color-on-primary); border-radius: 3px; }
.site-nav { display: flex; align-items: center; gap: var(--space-1); margin-left: auto; flex-wrap: wrap; }
.site-nav a {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: var(--min-tap); padding: 0 var(--space-2);
  color: var(--color-muted); font-size: var(--fs-sm); border-radius: var(--radius-sm);
  transition: color var(--motion-fast) var(--easing), background var(--motion-fast) var(--easing);
}
.site-nav a:hover { color: var(--color-on-surface); background: var(--color-surface-2); text-decoration: none; }
/* 回主站的入口刻意做得最轻：颜色更暗、字号更小、没有任何按钮感 */
.site-nav .nav-quiet { color: var(--color-dim); font-size: var(--fs-xs); }
.site-nav .nav-quiet:hover { color: var(--color-muted); background: transparent; text-decoration: underline; }
.nav-toggle {
  display: none; margin-left: auto; min-height: var(--min-tap); min-width: var(--min-tap);
  background: var(--color-surface-2); color: var(--color-on-surface);
  border: 1px solid var(--color-outline); border-radius: var(--radius-sm); cursor: pointer;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-1);
  min-height: var(--min-tap); padding: 0 var(--space-3);
  border-radius: var(--radius-sm); font-size: var(--fs-sm); font-weight: 600;
  border: 1px solid transparent; cursor: pointer; font-family: inherit;
  transition: transform var(--motion-fast) var(--easing), background var(--motion-fast) var(--easing), border-color var(--motion-fast) var(--easing);
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn:disabled { opacity: .55; cursor: not-allowed; transform: none; }
.btn-primary { background: var(--color-primary); color: var(--color-on-primary); }
.btn-primary:hover { background: #85AEFF; }
.btn-ghost { border-color: var(--color-outline); color: var(--color-on-surface); background: transparent; }
.btn-ghost:hover { border-color: var(--color-primary); background: var(--color-primary-soft); }
.btn-sm { min-height: 36px; padding: 0 var(--space-2); font-size: var(--fs-xs); }
.text-btn { background: none; border: 0; padding: var(--space-1) 0; min-height: var(--min-tap); color: var(--color-muted); font-size: var(--fs-sm); cursor: pointer; font-family: inherit; }
.text-btn:hover { color: var(--color-primary); text-decoration: underline; }

/* ---------- Hero ---------- */
.bridge-hero {
  position: relative; isolation: isolate; overflow: hidden;
  min-height: 60vh; min-height: 60svh;
  display: flex; align-items: center;
  background: #060B18;
  border-bottom: 1px solid rgba(42, 53, 87, .7);
}
.bridge-hero::after {
  content: ""; position: absolute; inset: 0; z-index: 1; pointer-events: none;
  background:
    linear-gradient(90deg, rgba(6, 11, 24, .98) 0%, rgba(6, 11, 24, .90) 38%, rgba(6, 11, 24, .38) 72%, rgba(6, 11, 24, .10) 100%),
    linear-gradient(180deg, rgba(6, 11, 24, .40) 0%, transparent 24%, transparent 70%, var(--color-bg) 100%);
}
/* 只露出主站那颗代码地球的一角，低对比、静态，作为不张扬的呼应 */
.bridge-hero__echo {
  position: absolute; z-index: 0; right: -190px; top: 50%;
  width: 620px; height: 620px; transform: translateY(-50%);
  border-radius: 50%;
  background: url("earth-echo.webp") center / cover no-repeat;
  opacity: .22; filter: blur(2px) saturate(.75);
  -webkit-mask-image: radial-gradient(circle, #000 0 58%, transparent 80%);
  mask-image: radial-gradient(circle, #000 0 58%, transparent 80%);
}
.bridge-hero__echo::after {
  content: ""; position: absolute; inset: -18%; border-radius: 50%;
  background: radial-gradient(circle, rgba(80, 130, 255, .18), transparent 66%);
}
.bridge-hero__stars {
  position: absolute; inset: 0; z-index: 0; opacity: .5; pointer-events: none;
  background-image:
    radial-gradient(1px 1px at 12% 22%, rgba(196, 218, 255, .8) 99%, transparent),
    radial-gradient(1px 1px at 28% 76%, rgba(196, 218, 255, .6) 99%, transparent),
    radial-gradient(1.5px 1.5px at 58% 18%, rgba(150, 190, 255, .7) 99%, transparent),
    radial-gradient(1px 1px at 76% 62%, rgba(196, 218, 255, .55) 99%, transparent),
    radial-gradient(1px 1px at 92% 30%, rgba(196, 218, 255, .65) 99%, transparent);
}
.bridge-hero__inner { position: relative; z-index: 2; width: 100%; padding-top: var(--space-8); padding-bottom: var(--space-8); }
.eyebrow {
  display: inline-flex; align-items: center; gap: var(--space-1);
  font-size: var(--fs-xs); letter-spacing: .14em; color: #BBD2FF;
  background: rgba(107, 155, 255, .10); border: 1px solid rgba(107, 155, 255, .30);
  padding: 6px var(--space-2); border-radius: var(--radius-pill);
}
.bridge-hero h1 {
  margin: var(--space-3) 0 var(--space-2);
  max-width: 16em;
  font-size: clamp(34px, 5.4vw, 62px); line-height: 1.14;
  letter-spacing: -.026em; font-weight: 680;
  text-shadow: 0 4px 30px rgba(0, 0, 0, .5);
}
.bridge-hero h1 .accent {
  background: linear-gradient(100deg, #A8C8FF 0%, var(--color-primary) 48%, #7FD1FF 100%);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: var(--color-primary);
}
.hero-sub { max-width: 620px; font-size: clamp(16px, 1.5vw, 19px); color: #C6D1E7; margin: 0 0 var(--space-3); }
.status-row { display: flex; align-items: center; flex-wrap: wrap; gap: var(--space-2); margin-bottom: var(--space-2); }
.status-pill {
  display: inline-flex; align-items: center; gap: var(--space-1);
  min-height: 30px; padding: 0 var(--space-2);
  font-size: var(--fs-xs); border-radius: var(--radius-pill);
  background: rgba(18, 26, 46, .7); border: 1px solid var(--color-outline); color: var(--color-muted);
}
.status-pill i { width: 7px; height: 7px; border-radius: 50%; background: var(--color-dim); flex: none; }
.status-pill.is-online i { background: var(--color-success); box-shadow: 0 0 8px rgba(127, 209, 168, .7); }
.status-pill.is-down i { background: var(--color-warn); box-shadow: 0 0 8px rgba(240, 192, 116, .6); }
.status-meta { font-size: var(--fs-xs); color: var(--color-dim); }
.from-note { margin: 0 0 var(--space-2); font-size: var(--fs-xs); color: var(--color-dim); letter-spacing: .02em; }
.hero-actions { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-top: var(--space-3); }
.bridge-hero .btn { min-height: 48px; padding: 0 var(--space-4); font-size: var(--fs-body); }
.bridge-hero .btn-ghost { background: rgba(255, 255, 255, .04); border-color: rgba(168, 190, 235, .38); }

/* ---------- Sections ---------- */
.section { padding: var(--space-6) 0; }
.section-head { display: flex; align-items: flex-end; justify-content: space-between; gap: var(--space-3); flex-wrap: wrap; margin-bottom: var(--space-3); }
.section-head h2 { margin: 0; font-size: var(--fs-h2); line-height: 1.25; font-weight: 600; }
.section-head p { margin: var(--space-1) 0 0; color: var(--color-muted); font-size: var(--fs-sm); }
.section-kicker { color: var(--color-primary); font-size: var(--fs-xs); letter-spacing: .14em; margin-bottom: var(--space-1); }

/* ---------- Workbench ---------- */
.workbench { display: grid; grid-template-columns: minmax(0, 1fr) 280px; gap: var(--space-3); align-items: start; }
.panel {
  background: linear-gradient(160deg, var(--color-surface-2), var(--color-surface));
  border: 1px solid var(--color-outline); border-radius: var(--radius-lg);
  padding: var(--space-4);
}
.panel-head { display: flex; align-items: flex-start; gap: var(--space-2); margin-bottom: var(--space-3); }
.panel-icon {
  display: grid; place-items: center; width: 40px; height: 40px; flex: none;
  border-radius: var(--radius-sm); background: var(--color-primary-soft);
  border: 1px solid rgba(107, 155, 255, .34); color: var(--color-primary); font-size: var(--fs-lg);
}
.panel-head h3 { margin: 0 0 4px; font-size: var(--fs-h4); font-weight: 600; }
.panel-head p { margin: 0; font-size: var(--fs-sm); color: var(--color-muted); }
.form { display: grid; gap: var(--space-2); max-width: 420px; }
.form .btn { justify-self: start; }
.field { display: grid; gap: 6px; font-size: var(--fs-sm); color: var(--color-muted); }
.field input, .field select, .url-form input {
  min-height: var(--min-tap); width: 100%;
  background: #0C1428; border: 1px solid var(--color-outline);
  border-radius: var(--radius-sm); color: var(--color-on-surface);
  padding: 0 var(--space-2); font-size: var(--fs-sm); font-family: inherit;
}
.field input::placeholder, .url-form input::placeholder { color: #6E7C9A; }
.field input:focus, .field select:focus, .url-form input:focus { border-color: var(--color-primary); }
.form-msg { min-height: 20px; margin: var(--space-2) 0 0; font-size: var(--fs-sm); }
.form-msg.is-error { color: var(--color-danger); }
.form-msg.is-ok { color: var(--color-success); }
.auth-foot { border-top: 1px solid var(--color-outline); margin-top: var(--space-3); padding-top: var(--space-1); }

.work-top { display: flex; align-items: center; justify-content: space-between; gap: var(--space-2); margin-bottom: var(--space-3); flex-wrap: wrap; }
.who { font-size: var(--fs-sm); color: var(--color-muted); }
.who strong { color: var(--color-on-surface); }
.url-form { display: grid; gap: var(--space-1); }
.url-form > label { font-size: var(--fs-sm); color: var(--color-muted); }
.url-row { display: flex; gap: var(--space-1); }
.url-row input { flex: 1; min-width: 0; font-family: var(--mono); }
.hint { margin: 0; font-size: var(--fs-xs); color: var(--color-dim); }
.hint code { color: var(--color-muted); }

.parse-result { margin-top: var(--space-3); padding: var(--space-3); background: rgba(8, 13, 28, .6); border: 1px solid var(--color-outline); border-radius: var(--radius-md); }
.parse-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-2); }
.field-wide { grid-column: 1 / -1; }
.parse-actions { display: flex; flex-wrap: wrap; gap: var(--space-1); margin-top: var(--space-3); }

.result { margin-top: var(--space-3); }
.result:empty { display: none; }
.result-card { padding: var(--space-2) var(--space-3); border-radius: var(--radius-md); border: 1px solid var(--color-outline); background: var(--color-surface); font-size: var(--fs-sm); }
.result-card.is-ok { border-color: rgba(127, 209, 168, .40); background: var(--color-success-soft); }
.result-card.is-error { border-color: rgba(240, 138, 130, .40); background: rgba(240, 138, 130, .08); }
.result-card.is-warn { border-color: rgba(240, 192, 116, .40); background: var(--color-warn-soft); }
.result-card h4 { margin: 0 0 6px; font-size: var(--fs-sm); font-weight: 600; color: var(--color-on-surface); }
.result-card p { margin: 0 0 var(--space-1); color: var(--color-muted); }
.result-actions { display: flex; flex-wrap: wrap; gap: var(--space-1); margin-top: var(--space-2); }
.progress { height: 4px; border-radius: var(--radius-pill); background: var(--color-outline); overflow: hidden; margin: var(--space-2) 0 0; }
.progress i { display: block; height: 100%; width: 36%; background: var(--color-primary); border-radius: inherit; animation: progressSlide 1.8s ease-in-out infinite; }
@keyframes progressSlide { 0% { transform: translateX(-100%); } 100% { transform: translateX(320%); } }

.tree-box, .search-results, .task-list { margin-top: var(--space-3); }
.list-head { font-size: var(--fs-xs); letter-spacing: .1em; color: var(--color-dim); margin-bottom: var(--space-1); }
.list-row {
  display: flex; align-items: center; gap: var(--space-2);
  min-height: var(--min-tap); padding: var(--space-1) var(--space-2);
  border: 1px solid var(--color-outline); border-radius: var(--radius-sm);
  background: rgba(8, 13, 28, .45); margin-bottom: 6px;
  font-size: var(--fs-sm); color: var(--color-muted);
}
.list-row + .list-row { margin-top: 0; }
.list-row .name { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-family: var(--mono); color: var(--color-on-surface); }
.list-row .sub { color: var(--color-dim); font-size: var(--fs-xs); white-space: nowrap; }
.list-row .btn { flex: none; }
.list-row button.pick { background: none; border: 0; color: var(--color-primary); cursor: pointer; font-size: var(--fs-sm); min-height: var(--min-tap); padding: 0 var(--space-1); font-family: inherit; }
.list-row button.pick:hover { text-decoration: underline; }
.search-box { border-top: 1px solid var(--color-outline); margin-top: var(--space-4); padding-top: var(--space-3); }
.empty { color: var(--color-dim); font-size: var(--fs-sm); margin: 0; }

.side-note {
  padding: var(--space-3); border: 1px solid var(--color-outline);
  border-radius: var(--radius-lg); background: rgba(18, 26, 46, .55);
}
.side-note__mark { width: 28px; height: 3px; border-radius: var(--radius-pill); background: linear-gradient(90deg, var(--color-primary), transparent); margin-bottom: var(--space-2); }
.side-note h3 { margin: 0 0 var(--space-1); font-size: var(--fs-sm); font-weight: 600; }
.side-note p { margin: 0 0 var(--space-2); font-size: var(--fs-sm); color: var(--color-muted); }
.side-note ul { margin: 0; padding-left: var(--space-3); font-size: var(--fs-xs); color: var(--color-dim); }
.side-note li { margin-bottom: 6px; }
.side-note strong { color: var(--color-warn); }

/* ---------- How / examples ---------- */
.steps-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: var(--space-2); }
.step-card { padding: var(--space-3); border: 1px solid var(--color-outline); border-radius: var(--radius-md); background: var(--color-surface); }
.step-num { display: block; font-family: var(--mono); font-size: var(--fs-xs); color: var(--color-primary); letter-spacing: .1em; margin-bottom: var(--space-1); }
.step-card h3 { margin: 0 0 6px; font-size: var(--fs-h4); font-weight: 600; }
.step-card p { margin: 0; font-size: var(--fs-sm); color: var(--color-muted); }
.examples { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); gap: var(--space-3); margin-top: var(--space-3); }
.examples__code { position: relative; background: #080D1A; border: 1px solid var(--color-outline); border-radius: var(--radius-md); padding: var(--space-3); overflow-x: auto; }
.examples__label { display: block; font-size: var(--fs-xs); color: var(--color-dim); letter-spacing: .1em; margin-bottom: var(--space-2); }
.examples__code pre { margin: 0; font-size: var(--fs-sm); line-height: 1.9; color: #BBD0F2; white-space: pre; }
.examples__text { padding: var(--space-2) 0; }
.examples__text h3 { margin: 0 0 var(--space-1); font-size: var(--fs-h4); font-weight: 600; }
.examples__text p { margin: 0 0 var(--space-2); font-size: var(--fs-sm); color: var(--color-muted); }

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--color-outline); background: rgba(8, 12, 24, .6); margin-top: var(--space-8); }
.footer-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: var(--space-4); padding: var(--space-6) 0 var(--space-4); }
.footer-grid h3 { font-size: var(--fs-sm); margin: 0 0 var(--space-2); font-weight: 600; }
.footer-grid p, .footer-grid a { display: block; color: var(--color-muted); font-size: var(--fs-sm); margin: 0 0 var(--space-1); }
.footer-grid a:hover { color: var(--color-primary); }
.footer-bottom { border-top: 1px solid var(--color-outline); padding: var(--space-3) 0; display: flex; align-items: center; justify-content: center; flex-wrap: wrap; gap: var(--space-2) var(--space-3); text-align: center; font-size: var(--fs-sm); color: var(--color-muted); }
.footer-bottom a { color: var(--color-muted); }
.footer-bottom a:hover { color: var(--color-primary); }
.footer-note { text-align: center; color: var(--color-dim); font-size: var(--fs-xs); padding-bottom: var(--space-3); }

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .workbench { grid-template-columns: 1fr; }
  .side-note { order: 2; }
}
@media (max-width: 768px) {
  .container { padding: 0 var(--space-2); }
  .header-inner { min-height: 64px; }
  .site-nav { display: none; position: absolute; top: 64px; left: 0; right: 0; padding: var(--space-2); background: var(--color-bg); border-bottom: 1px solid var(--color-outline); flex-direction: column; align-items: stretch; }
  .site-nav.open { display: flex; }
  .site-nav a { justify-content: flex-start; }
  .nav-toggle { display: inline-flex; align-items: center; justify-content: center; }
  .bridge-hero { min-height: 74vh; min-height: 74svh; }
  .bridge-hero__echo { right: -300px; opacity: .14; }
  .bridge-hero::after { background: linear-gradient(180deg, rgba(6, 11, 24, .62), rgba(6, 11, 24, .88) 48%, var(--color-bg) 100%); }
  .bridge-hero__inner { padding-top: var(--space-6); padding-bottom: var(--space-6); }
  .bridge-hero h1 { font-size: clamp(30px, 8.4vw, 44px); }
  .section { padding: var(--space-4) 0; }
  .panel { padding: var(--space-3); }
  .parse-grid { grid-template-columns: 1fr; }
  .field-wide { grid-column: auto; }
  .examples { grid-template-columns: 1fr; }
  .url-row { flex-direction: column; }
  .url-row .btn { width: 100%; }
  .hero-actions .btn { flex: 1 1 auto; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; }
}