/* ============================================================
   6号平台服务 · 共享样式表 /assets/site.css
   深墨背景分区 + 信号橙状态 + 数字青读数 + 暖纸长文区
   ============================================================ */

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

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

body, h1, h2, h3, h4, h5, p, ul, ol, figure, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; }
button, input, select, textarea { font: inherit; color: inherit; }
button {
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }

/* ---------- tokens ---------- */
:root {
  --ink-900: #071A2B;
  --ink-700: #0E2A44;
  --ink-500: #1B4059;
  --orange: #FF6A2B;
  --orange-deep: #D94A12;
  --cyan: #3FE0D0;
  --silver: #C7D0D8;
  --silver-dim: #8A9AA6;
  --paper: #F2E8DA;
  --paper-deep: #E3D5C2;

  --display: "Barlow Semi Condensed", "Archivo Narrow", "Noto Sans SC", "PingFang SC", sans-serif;
  --body: "HarmonyOS Sans SC", "Noto Sans SC", "PingFang SC", system-ui, sans-serif;
  --mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, monospace;

  --rail-w: 72px;
  --maxw: 1180px;
  --gutter: clamp(16px, 4vw, 40px);
  --line: 1px solid var(--ink-500);
  --line-strong: 2px solid var(--ink-500);
  --hard: 5px 5px 0 var(--ink-500);
  --radius: 2px;
}

/* ---------- base ---------- */
body {
  min-height: 100vh;
  background-color: var(--ink-900);
  background-image:
    linear-gradient(to right, rgba(63, 224, 208, 0.045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(63, 224, 208, 0.045) 1px, transparent 1px);
  background-size: 72px 72px;
  background-position: -1px -1px;
  color: var(--silver);
  font-family: var(--body);
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
  font-family: var(--display);
  font-weight: 800;
  letter-spacing: -0.01em;
  line-height: 1.15;
  color: var(--paper);
}
h1 { font-size: clamp(1.75rem, 4vw, 2.75rem); }
h2 { font-size: clamp(1.375rem, 3vw, 2rem); }
h3 { font-size: clamp(1.125rem, 2vw, 1.375rem); }
h4 { font-size: 1.0625rem; }

p { max-width: 72ch; }
small { font-size: 0.875rem; }

::selection {
  background: var(--orange);
  color: var(--ink-900);
}

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

/* ---------- utilities ---------- */
.mono {
  font-family: var(--mono);
  font-size: 0.8125rem;
  letter-spacing: 0.02em;
}
.dim { color: var(--silver-dim); }
.cyan { color: var(--cyan); }
.orange { color: var(--orange); }

.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--gutter);
}
.wrap--narrow { max-width: 820px; }

.rule {
  border: 0;
  border-top: var(--line);
  margin: clamp(28px, 5vw, 48px) 0;
}

.hard-edge {
  border: var(--line-strong);
  box-shadow: var(--hard);
  background: var(--ink-700);
  padding: clamp(18px, 3vw, 32px);
  border-radius: var(--radius);
}

.grid { display: grid; gap: clamp(16px, 3vw, 32px); }
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }

.prose {
  max-width: 68ch;
  color: var(--silver);
}
.prose > * + * { margin-top: 1.1em; }
.prose h2 { margin-top: 1.9em; }
.prose h3 { margin-top: 1.5em; }
.prose ul { list-style: none; }
.prose li {
  position: relative;
  padding-left: 1.1em;
  margin-top: 0.4em;
}
.prose li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 8px;
  height: 2px;
  background: var(--orange);
}
.prose code {
  font-family: var(--mono);
  font-size: 0.875em;
  background: var(--ink-700);
  border: var(--line);
  padding: 1px 6px;
  border-radius: var(--radius);
}
.prose a {
  color: var(--cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* 暖纸长文区 */
.paper-zone {
  background: var(--paper);
  color: var(--ink-900);
}
.paper-zone h1,
.paper-zone h2,
.paper-zone h3,
.paper-zone h4 { color: var(--ink-900); }
.paper-zone a {
  color: var(--orange-deep);
  text-decoration: underline;
  text-underline-offset: 3px;
}
.paper-zone code {
  background: var(--paper-deep);
  border-color: rgba(7, 26, 43, 0.18);
  color: var(--ink-900);
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 18px;
  border: var(--line);
  border-radius: var(--radius);
  font-family: var(--body);
  font-size: 0.9375rem;
  font-weight: 500;
  line-height: 1.2;
  color: var(--silver);
  background: transparent;
  transition: color 150ms ease, border-color 150ms ease, background-color 150ms ease, box-shadow 150ms ease;
}
.btn:hover {
  color: var(--cyan);
  border-color: var(--cyan);
}
.btn--primary {
  background: var(--orange);
  border-color: var(--orange);
  color: var(--ink-900);
  font-weight: 700;
  box-shadow: 4px 4px 0 var(--ink-500);
}
.btn--primary:hover {
  background: var(--orange-deep);
  border-color: var(--orange-deep);
  color: var(--paper);
}
.btn--primary:active {
  transform: translate(2px, 2px);
  box-shadow: 1px 1px 0 var(--ink-500);
}
.btn--ghost {
  border-color: var(--cyan);
  color: var(--cyan);
}
.btn--ghost:hover {
  background: rgba(63, 224, 208, 0.12);
}

/* ---------- tags & crumbs ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border: var(--line);
  border-radius: var(--radius);
  font-family: var(--mono);
  font-size: 0.8125rem;
  letter-spacing: 0.02em;
  color: var(--cyan);
  background: transparent;
  transition: color 120ms ease, background-color 120ms ease, border-color 120ms ease;
}
.tag:hover { border-color: var(--cyan); }
.tag--active,
.tag[aria-pressed="true"] {
  background: var(--orange);
  border-color: var(--orange);
  color: var(--ink-900);
  font-weight: 600;
}
.tag--cyan {
  border-color: var(--cyan);
  color: var(--ink-900);
  background: var(--cyan);
}

.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--mono);
  font-size: 0.8125rem;
  letter-spacing: 0.02em;
  color: var(--silver-dim);
}
.crumbs a { color: var(--silver-dim); }
.crumbs a:hover { color: var(--cyan); }
.crumbs__sep { color: var(--ink-500); }

/* ---------- media containers ---------- */
.media {
  position: relative;
  display: block;
  width: 100%;
  overflow: hidden;
  border: var(--line);
  border-radius: var(--radius);
  background: var(--ink-700);
}
.media > img,
.media > svg,
.media > video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.media--16x9 { aspect-ratio: 16 / 9; }
.media--4x3 { aspect-ratio: 4 / 3; }
.media--1x1 { aspect-ratio: 1 / 1; }
.media--4x5 { aspect-ratio: 4 / 5; }
.media--map {
  background-color: var(--ink-700);
  background-image:
    radial-gradient(circle at 22% 30%, rgba(63, 224, 208, 0.24) 0 2px, transparent 2px),
    radial-gradient(circle at 68% 62%, rgba(255, 106, 43, 0.22) 0 2px, transparent 2px),
    radial-gradient(circle at 44% 82%, rgba(199, 208, 216, 0.16) 0 2px, transparent 2px),
    repeating-linear-gradient(115deg, rgba(63, 224, 208, 0.07) 0 1px, transparent 1px 14px);
}
.media__label {
  position: absolute;
  left: 10px;
  bottom: 10px;
  padding: 3px 8px;
  border-radius: var(--radius);
  background: var(--ink-900);
  color: var(--cyan);
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
}
.media__caption {
  margin-top: 8px;
  font-family: var(--mono);
  font-size: 0.8125rem;
  color: var(--silver-dim);
}

/* ---------- skip link ---------- */
.skip-link {
  position: fixed;
  left: 10px;
  top: -80px;
  z-index: 400;
  padding: 10px 16px;
  border-radius: var(--radius);
  background: var(--orange);
  color: var(--ink-900);
  font-family: var(--mono);
  font-size: 0.8125rem;
  font-weight: 600;
  transition: top 180ms ease;
}
.skip-link:focus {
  top: 10px;
}

/* ============================================================
   HEADER
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 200;
  background: var(--ink-900);
  border-bottom: var(--line-strong);
}

/* --- rail --- */
.rail {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px var(--gutter);
  background: var(--ink-700);
  border-bottom: var(--line);
}
.rail__brand {
  font-family: var(--display);
  font-weight: 800;
  font-size: 1.0625rem;
  letter-spacing: 0.04em;
  color: var(--paper);
  line-height: 1;
}
.rail__brand span { color: var(--orange); }
.rail__meta {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: auto;
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--silver-dim);
}
.rail__label { color: var(--ink-500); }
.rail__num { color: var(--cyan); font-weight: 600; }
.rail__track { display: none; }
.rail__top {
  padding: 4px 10px;
  border: var(--line);
  border-radius: var(--radius);
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--silver-dim);
  transition: color 150ms ease, border-color 150ms ease;
}
.rail__top:hover {
  color: var(--cyan);
  border-color: var(--cyan);
}

/* --- masthead --- */
.site-header__inner {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--gutter);
}
.masthead {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: clamp(18px, 3vw, 30px) 0 clamp(12px, 2vw, 18px);
  text-align: center;
}
.masthead__kicker {
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--silver-dim);
  max-width: none;
}
.masthead__brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
}
.masthead__mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: var(--radius);
  background: var(--orange);
  color: var(--ink-900);
  font-family: var(--display);
  font-weight: 800;
  font-size: 1.5rem;
  line-height: 1;
  box-shadow: 3px 3px 0 var(--ink-500);
}
.masthead__name {
  font-family: var(--display);
  font-weight: 800;
  font-size: clamp(1.75rem, 4.4vw, 2.6rem);
  letter-spacing: -0.01em;
  line-height: 1.05;
  color: var(--paper);
}
.masthead__brand:hover .masthead__name { color: var(--cyan); }
.masthead__tagline {
  font-family: var(--mono);
  font-size: 0.8125rem;
  letter-spacing: 0.2em;
  color: var(--cyan);
  max-width: none;
}

/* --- navbar --- */
.navbar {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 0;
  border-top: var(--line);
}
.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: var(--line);
  border-radius: var(--radius);
  font-family: var(--mono);
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  color: var(--silver);
}
.nav-toggle:hover { border-color: var(--cyan); color: var(--cyan); }
.nav-toggle__bars {
  position: relative;
  display: block;
  width: 16px;
  height: 2px;
  background: currentColor;
}
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 2px;
  background: currentColor;
}
.nav-toggle__bars::before { top: -5px; }
.nav-toggle__bars::after { top: 5px; }
.nav-toggle[aria-expanded="true"] {
  border-color: var(--orange);
  color: var(--orange);
}

.nav { display: none; }
.nav[data-open] { display: block; }

.nav__list {
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  align-items: center;
}
.nav__link {
  position: relative;
  display: inline-block;
  padding: 8px 12px;
  border-radius: var(--radius);
  font-family: var(--body);
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--silver);
  transition: color 150ms ease, background-color 150ms ease;
}
.nav__link:hover {
  color: var(--paper);
  background: var(--ink-700);
}
.nav__link[aria-current="page"] {
  color: var(--paper);
  background: var(--ink-700);
}
.nav__link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: 2px;
  height: 2px;
  background: var(--orange);
}

.utils {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}
.util {
  padding: 7px 11px;
  border: var(--line);
  border-radius: var(--radius);
  background: transparent;
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--silver-dim);
  transition: color 150ms ease, border-color 150ms ease, background-color 150ms ease;
}
.util:hover {
  color: var(--cyan);
  border-color: var(--cyan);
}
.util--cta {
  background: var(--orange);
  border-color: var(--orange);
  color: var(--ink-900);
  font-weight: 600;
}
.util--cta:hover {
  background: var(--orange-deep);
  border-color: var(--orange-deep);
  color: var(--paper);
}

@media (max-width: 1023px) {
  .nav {
    position: absolute;
    left: calc(var(--gutter) * -1);
    right: calc(var(--gutter) * -1);
    top: 100%;
    padding: 6px var(--gutter) 18px;
    background: var(--ink-700);
    border-top: var(--line);
    border-bottom: var(--line-strong);
  }
  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }
  .nav__link {
    display: block;
    padding: 13px 2px;
    border-bottom: var(--line);
    border-radius: 0;
    font-size: 1.0625rem;
  }
  .nav__link[aria-current="page"] { background: transparent; }
  .nav__link[aria-current="page"]::after {
    left: 2px;
    right: auto;
    bottom: 4px;
    width: 22px;
  }
  .utils { margin-left: auto; }
}

@media (min-width: 1024px) {
  .nav-toggle { display: none; }
  .navbar {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    padding: 10px 0 12px;
  }
  .nav { grid-column: 2; display: block; }
  .utils {
    grid-column: 3;
    justify-self: end;
    justify-content: flex-end;
  }
  .util--top { display: none; }
}

/* desktop rail */
@media (min-width: 1024px) {
  body { padding-left: var(--rail-w); }
  .rail {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    z-index: 210;
    width: var(--rail-w);
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    gap: 20px;
    padding: 22px 0 16px;
    border-bottom: 0;
    border-right: var(--line);
  }
  .rail__brand {
    writing-mode: vertical-rl;
    font-size: 1rem;
    letter-spacing: 0.2em;
    padding: 4px 0;
  }
  .rail__meta {
    flex-direction: column;
    align-items: center;
    gap: 12px;
    margin: auto 0 0;
  }
  .rail__label { display: none; }
  .rail__num { font-size: 0.8125rem; }
  .rail__track {
    display: block;
    position: relative;
    width: 2px;
    height: 104px;
    background: var(--ink-500);
    overflow: hidden;
    border-radius: 2px;
  }
  .rail__fill {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 0;
    background: var(--orange);
  }
  .rail__top {
    writing-mode: vertical-rl;
    padding: 12px 6px;
    letter-spacing: 0.24em;
  }
}

/* copy feedback */
.toast {
  position: fixed;
  left: var(--gutter);
  bottom: 24px;
  z-index: 320;
  max-width: calc(100vw - 2 * var(--gutter));
  padding: 10px 16px;
  border-radius: var(--radius);
  background: var(--cyan);
  color: var(--ink-900);
  font-family: var(--mono);
  font-size: 0.8125rem;
  font-weight: 600;
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity 180ms ease, transform 180ms ease;
}
.toast[data-show] {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================================
   FOOTER
   ============================================================ */
.site-footer {
  margin-top: clamp(48px, 8vw, 96px);
  background: var(--ink-900);
  border-top: var(--line-strong);
}
.footer__inner {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(32px, 6vw, 56px) var(--gutter) 0;
}
.footer__top {
  display: grid;
  grid-template-columns: minmax(240px, 1fr) 2fr;
  gap: clamp(24px, 5vw, 64px);
  padding-bottom: clamp(24px, 4vw, 40px);
  border-bottom: var(--line);
}
.footer__brand { display: flex; flex-direction: column; align-items: flex-start; gap: 14px; }
.footer__mark {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--display);
  font-weight: 800;
  font-size: 1.375rem;
  letter-spacing: -0.01em;
  color: var(--paper);
  max-width: none;
}
.footer__mark span {
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  border-radius: var(--radius);
  background: var(--orange);
  color: var(--ink-900);
  font-size: 1.0625rem;
  line-height: 1;
}
.footer__tagline {
  max-width: 34ch;
  font-size: 0.9375rem;
  color: var(--silver-dim);
}
.footer__grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(18px, 3vw, 32px);
}
.footer__title {
  font-family: var(--mono);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--cyan);
}
.footer__title::after {
  content: "";
  display: block;
  width: 24px;
  height: 2px;
  margin-top: 8px;
  background: var(--ink-500);
}
.footer__links { margin-top: 14px; }
.footer__links li + li { margin-top: 2px; }
.footer__links a {
  display: inline-block;
  padding: 4px 0;
  font-size: 0.9375rem;
  color: var(--silver);
  transition: color 150ms ease;
}
.footer__links a:hover {
  color: var(--orange);
}

.footer__contact {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 8px clamp(16px, 3vw, 32px);
  padding: clamp(20px, 3vw, 28px) 0;
  border-bottom: var(--line);
}
.footer__line {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-size: 0.9375rem;
  color: var(--silver);
  max-width: none;
}
.footer__line .mono {
  flex: none;
  padding: 1px 7px;
  border: var(--line);
  border-radius: var(--radius);
  color: var(--silver-dim);
  font-size: 0.75rem;
}
.footer__line--note {
  grid-column: 1 / -1;
  font-size: 0.875rem;
  color: var(--silver-dim);
  max-width: 62ch;
}

.footer__legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 22px;
  padding: 18px 0 26px;
  font-family: var(--mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--silver-dim);
}
.footer__legal p { max-width: none; }
.footer__icp { color: var(--silver); }
.footer__copy { margin-left: auto; }

@media (max-width: 900px) {
  .footer__top { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  .footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer__contact { grid-template-columns: 1fr; }
  .footer__copy { margin-left: 0; }
}
@media (max-width: 420px) {
  .footer__grid { grid-template-columns: 1fr; }
}

/* ---------- motion preferences ---------- */
@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;
  }
}