/* ============================================================
   6686官方 · 共享样式 /assets/site.css
   框架式导航 + 编辑部版式 + 冰城蓝/信号橙体系
   ============================================================ */

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

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

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

/* ---------- 变量 ---------- */
:root {
  --paper: #F4F1EA;
  --fog: #E3E8E8;
  --ice: #2C6E9B;
  --deep: #12384F;
  --ink: #101820;
  --signal: #F26B21;
  --frost: #A9D3E6;
  --snow: #FFFFFF;
  --pine: #2F6B55;
  --brick: #A93E2A;

  --line: 2px solid var(--ink);
  --shadow-hard: 6px 6px 0 var(--ink);

  --font-display: "Barlow Condensed", "Noto Sans SC", "Source Han Sans SC", "PingFang SC", sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "IBM Plex Mono", "JetBrains Mono", "Roboto Mono", ui-monospace, monospace;

  --wrap: 1240px;
  --gutter: clamp(16px, 4vw, 40px);
  --ease: cubic-bezier(.2, .7, .3, 1);
}

/* ---------- 基础排版 ---------- */
body {
  background-color: var(--paper);
  background-image: repeating-linear-gradient(115deg, rgba(44, 110, 155, .055) 0 1px, transparent 1px 26px);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: clamp(16px, 1.05vw, 17px);
  line-height: 1.8;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
}

p, li, dd { text-wrap: pretty; }

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

:focus-visible {
  outline: 3px solid var(--signal);
  outline-offset: 3px;
}
:focus:not(:focus-visible) { outline: none; }

#main-content { display: block; }

/* ---------- skip link ---------- */
.skip-link {
  position: fixed;
  top: -140px;
  left: 12px;
  z-index: 200;
  padding: 10px 18px;
  background: var(--ink);
  color: var(--paper);
  border: 2px solid var(--signal);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .04em;
  transition: top .18s var(--ease);
}
.skip-link:focus { top: 12px; }

/* ============================================================
   头部：浏览器窗口外框
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  background: var(--paper);
  border-bottom: var(--line);
}

.scroll-meter {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 2px;
  background: transparent;
  z-index: 3;
  pointer-events: none;
}
.scroll-meter__bar {
  display: block;
  width: 0;
  height: 100%;
  background: var(--signal);
  transition: width .12s linear;
}

/* 窗口把手条 */
.frame-bar {
  background: var(--deep);
  color: var(--frost);
  border-bottom: 2px solid var(--ink);
}
.frame-bar__inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 5px var(--gutter);
  display: flex;
  align-items: center;
  gap: 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  line-height: 1.6;
  letter-spacing: .1em;
}
.traffic { display: inline-flex; align-items: center; gap: 5px; flex: 0 0 auto; }
.traffic__dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--frost);
  opacity: .45;
}
.traffic__dot--one { background: var(--signal); opacity: 1; }
.traffic__dot--two { background: var(--frost); opacity: .9; }
.traffic__dot--three { background: var(--pine); opacity: .95; }

.frame-url {
  color: var(--snow);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.frame-meta {
  margin-left: auto;
  color: var(--frost);
  opacity: .72;
  white-space: nowrap;
}
.frame-chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 2px 9px;
  background: var(--signal);
  color: var(--ink);
  border: 1.5px solid var(--ink);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .06em;
  white-space: nowrap;
  transition: background-color .16s var(--ease), transform .16s var(--ease);
}
.frame-chip:hover { background: var(--frost); transform: translateY(-1px); }
.frame-chip__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--ink);
  flex: 0 0 auto;
}

/* 主体三栏 */
.header-main {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 12px var(--gutter);
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: clamp(14px, 2.4vw, 32px);
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
}
.brand__mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  background: var(--ice);
  color: var(--snow);
  border: 2px solid var(--ink);
  box-shadow: 3px 3px 0 var(--ink);
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 600;
  line-height: 1;
  transition: background-color .16s var(--ease);
}
.brand:hover .brand__mark { background: var(--signal); color: var(--ink); }
.brand__text { display: flex; flex-direction: column; line-height: 1.08; }
.brand__name {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 800;
  letter-spacing: .02em;
  color: var(--ink);
}
.brand__tag {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .3em;
  color: var(--ice);
}

/* 导航（标签页感） */
.site-nav { min-width: 0; justify-self: start; }
.site-nav__list {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 2px;
}
.site-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 9px 11px 7px;
  border-bottom: 3px solid transparent;
  font-size: 14.5px;
  font-weight: 600;
  color: var(--deep);
  transition: background-color .16s var(--ease), border-color .16s var(--ease), color .16s var(--ease);
}
.site-nav__link:hover {
  background: var(--fog);
  border-bottom-color: var(--ice);
}
.site-nav__index {
  font-family: var(--font-mono);
  font-size: 9.5px;
  font-weight: 400;
  letter-spacing: .08em;
  color: var(--ice);
  opacity: .85;
}
.site-nav__link[aria-current="page"] {
  background: var(--ice);
  color: var(--snow);
  border-bottom-color: var(--signal);
}
.site-nav__link[aria-current="page"] .site-nav__index { color: var(--frost); opacity: 1; }

/* 头部工具区 */
.header-tools {
  display: flex;
  align-items: center;
  gap: 8px;
  justify-self: end;
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border: 2px solid var(--ink);
  background: var(--snow);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  transition: background-color .16s var(--ease);
}
.nav-toggle__bars {
  display: inline-flex;
  flex-direction: column;
  gap: 3px;
  width: 18px;
}
.nav-toggle__bar {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--ink);
  transition: transform .2s var(--ease), opacity .2s var(--ease);
}
.nav-toggle__label { line-height: 1; }
.site-header[data-open] .nav-toggle { background: var(--signal); }
.site-header[data-open] .nav-toggle__bar:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bar:nth-child(2) { opacity: 0; }
.site-header[data-open] .nav-toggle__bar:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }

/* ============================================================
   通用按钮
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 18px;
  border: 2px solid var(--ink);
  background: var(--snow);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 14.5px;
  font-weight: 700;
  letter-spacing: .02em;
  line-height: 1.25;
  cursor: pointer;
  transition: transform .16s var(--ease), box-shadow .16s var(--ease), background-color .16s var(--ease), color .16s var(--ease);
}
.btn:hover { transform: translate(-2px, -2px); box-shadow: 4px 4px 0 var(--ink); }
.btn:active { transform: translate(0, 0); box-shadow: none; }
.btn--signal { background: var(--signal); color: var(--ink); }
.btn--ink { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.btn--ghost { background: transparent; color: var(--deep); }
.btn--ghost:hover { background: var(--fog); }
.btn--sm { padding: 8px 13px; font-size: 13px; }

/* ============================================================
   页脚：深冰蓝闭合版面
   ============================================================ */
.site-footer {
  background-color: var(--deep);
  background-image: repeating-linear-gradient(90deg, rgba(169, 211, 230, .07) 0 1px, transparent 1px 96px);
  color: var(--paper);
  border-top: 3px solid var(--ink);
}

.footer-top {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: clamp(36px, 6vw, 72px) var(--gutter) clamp(28px, 4vw, 48px);
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.4fr);
  gap: clamp(28px, 4vw, 60px);
  border-bottom: 1px solid rgba(169, 211, 230, .25);
}

.footer-lead {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 18px;
}

.brand--footer .brand__mark {
  background: var(--signal);
  color: var(--ink);
  box-shadow: 3px 3px 0 rgba(0, 0, 0, .55);
}
.brand--footer .brand__name { color: var(--snow); }
.brand--footer .brand__tag { color: var(--frost); }
.brand--footer:hover .brand__mark { background: var(--frost); }

.footer-words {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 4.4vw, 3.4rem);
  font-weight: 800;
  line-height: 1.02;
  letter-spacing: .01em;
  color: var(--snow);
}
.footer-words__accent { color: var(--signal); }

.footer-stamp {
  display: inline-block;
  transform: rotate(-2.5deg);
  padding: 4px 12px;
  border: 2px solid var(--signal);
  color: var(--signal);
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .22em;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 40px);
  align-items: start;
}

.footer-col__title {
  font-family: var(--font-mono);
  font-size: 11.5px;
  font-weight: 500;
  letter-spacing: .2em;
  color: var(--frost);
  margin-bottom: 14px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(169, 211, 230, .3);
}

.footer-list { display: flex; flex-direction: column; gap: 9px; }
.footer-link {
  display: inline-block;
  font-size: 14.5px;
  color: var(--paper);
  border-bottom: 1px solid transparent;
  transition: color .16s var(--ease), border-color .16s var(--ease);
}
.footer-link:hover { color: var(--signal); border-bottom-color: var(--signal); }

.footer-contact__line {
  display: flex;
  gap: 8px;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--paper);
  word-break: break-word;
}
.footer-contact__key {
  flex: 0 0 auto;
  padding-top: 3px;
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--frost);
}

.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin: 0 0 12px;
  padding: 6px 12px;
  border: 1.5px solid var(--frost);
  background: transparent;
  color: var(--frost);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  transition: background-color .16s var(--ease), color .16s var(--ease), border-color .16s var(--ease);
}
.copy-btn:hover { background: var(--frost); color: var(--deep); }
.copy-btn.is-done {
  background: var(--signal);
  border-color: var(--signal);
  color: var(--ink);
}

.footer-note {
  margin-top: 8px;
  padding-left: 10px;
  border-left: 2px solid var(--signal);
  font-size: 12.5px;
  line-height: 1.75;
  color: rgba(244, 241, 234, .7);
}

.footer-bottom {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 16px var(--gutter) 26px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 24px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .08em;
  color: var(--frost);
}
.footer-legal { display: inline-flex; align-items: center; gap: 8px; }
.footer-legal__key { color: rgba(169, 211, 230, .6); }
.footer-sign { margin-left: auto; color: rgba(169, 211, 230, .78); }

/* ============================================================
   版式容器与通用组件
   ============================================================ */
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.wrap--narrow { max-width: 840px; }

.section { padding-block: clamp(44px, 7vw, 92px); }
.section--fog { background: var(--fog); }
.section--deep { background: var(--deep); color: var(--paper); }
.section--deep .lead { color: rgba(244, 241, 234, .82); }
.section--deep .rule { border-top-color: rgba(169, 211, 230, .45); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .22em;
  color: var(--ice);
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 8px;
  background: var(--signal);
  border: 1.5px solid var(--ink);
  flex: 0 0 auto;
}
.section--deep .eyebrow { color: var(--frost); }
.section--deep .eyebrow::before { border-color: var(--frost); }

.display {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.4rem, 6.2vw, 5.2rem);
  line-height: .94;
  letter-spacing: -.02em;
  color: var(--ink);
  text-wrap: balance;
}
.section--deep .display { color: var(--snow); }

.lead {
  max-width: 62ch;
  font-size: clamp(1.02rem, 1.4vw, 1.19rem);
  line-height: 1.8;
  color: var(--deep);
}

.rule {
  border: 0;
  border-top: 2px solid var(--ink);
  margin-block: clamp(20px, 3vw, 32px);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border: 2px solid var(--ink);
  background: var(--snow);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  line-height: 1.6;
}
.tag--signal { background: var(--signal); }
.tag--ice { background: var(--ice); color: var(--snow); }

.panel {
  background: var(--snow);
  border: 2px solid var(--ink);
  box-shadow: var(--shadow-hard);
  padding: clamp(18px, 3vw, 30px);
}
.panel--fog { background: var(--fog); box-shadow: none; }

/* 面包屑 */
.crumbs {
  padding-block: 14px;
  border-bottom: 1px solid rgba(16, 24, 32, .16);
}
.crumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .08em;
  color: var(--deep);
}
.crumbs__item { display: inline-flex; align-items: center; gap: 8px; }
.crumbs__item + .crumbs__item::before {
  content: "›";
  color: var(--ice);
  font-size: 13px;
}
.crumbs__link {
  border-bottom: 1px solid rgba(44, 110, 155, .5);
  transition: color .16s var(--ease), border-color .16s var(--ease);
}
.crumbs__link:hover { color: var(--ice); border-bottom-color: var(--ice); }
.crumbs__item[aria-current="page"] { color: var(--ink); font-weight: 600; }

/* 图片容器（页面阶段放置占位图） */
.img-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 4 / 3;
  background: var(--fog);
  border: 2px solid var(--ink);
  box-shadow: var(--shadow-hard);
}
.img-frame > img,
.img-frame > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}
.img-frame--wide { aspect-ratio: 16 / 9; }
.img-frame--banner { aspect-ratio: 21 / 9; }
.img-frame--square { aspect-ratio: 1 / 1; }
.img-frame--tall { aspect-ratio: 3 / 4; }
.img-frame--flat { box-shadow: none; }
.img-frame--placeholder {
  background-image:
    repeating-linear-gradient(135deg, rgba(44, 110, 155, .16) 0 2px, transparent 2px 14px),
    linear-gradient(160deg, var(--fog), var(--snow));
}
.img-frame__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .08em;
  color: var(--deep);
}
.section--deep .img-frame__caption { color: var(--frost); }

/* 显现（JS 协作，无 JS 时保持可见） */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .34s var(--ease), transform .34s var(--ease);
}
html.js [data-reveal].is-in { opacity: 1; transform: none; }
html.js [data-reveal-delay="1"] { transition-delay: .08s; }
html.js [data-reveal-delay="2"] { transition-delay: .16s; }
html.js [data-reveal-delay="3"] { transition-delay: .24s; }

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1080px) {
  .frame-meta { display: none; }
  .frame-chip { margin-left: auto; }
  .site-nav__link { padding: 9px 9px 7px; font-size: 14px; }
}

@media (max-width: 1000px) {
  .header-main {
    grid-template-columns: minmax(0, 1fr) auto;
    padding: 10px var(--gutter);
  }
  .site-nav {
    grid-column: 1 / -1;
    justify-self: stretch;
    display: none;
    margin-top: 10px;
    padding-top: 10px;
    border-top: 2px solid var(--ink);
  }
  .site-header[data-open] .site-nav { display: block; }
  .site-nav__list { flex-direction: column; align-items: stretch; gap: 0; }
  .site-nav__item + .site-nav__item { border-top: 1px solid rgba(16, 24, 32, .16); }
  .site-nav__link {
    width: 100%;
    padding: 12px 4px;
    font-size: 16px;
    border-bottom: 0;
    border-left: 4px solid transparent;
  }
  .site-nav__link:hover { border-bottom: 0; border-left-color: var(--ice); }
  .site-nav__link[aria-current="page"] {
    background: var(--fog);
    color: var(--deep);
    border-bottom: 0;
    border-left-color: var(--signal);
  }
  .site-nav__link[aria-current="page"] .site-nav__index { color: var(--ice); }
  .header-tools .btn { display: none; }
  .nav-toggle { display: inline-flex; }
}

@media (max-width: 900px) {
  .footer-top { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-col--contact { grid-column: 1 / -1; }
}

@media (max-width: 600px) {
  .frame-bar__inner { font-size: 10.5px; gap: 10px; letter-spacing: .06em; }
  .frame-url { max-width: 46%; }
  .frame-chip { font-size: 10px; padding: 2px 7px; }
  .brand__mark { width: 34px; height: 34px; font-size: 13.5px; box-shadow: 2px 2px 0 var(--ink); }
  .brand__name { font-size: 19px; }
  .brand__tag { letter-spacing: .2em; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-sign { margin-left: 0; }
  .img-frame { box-shadow: 4px 4px 0 var(--ink); }
  .panel { box-shadow: 4px 4px 0 var(--ink); }
}

@media (max-width: 420px) {
  .traffic { display: none; }
  .frame-url { max-width: 52%; }
}

/* ---------- 降低动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    transition-delay: 0s !important;
  }
  html.js [data-reveal] { opacity: 1; transform: none; }
  .btn:hover { transform: none; box-shadow: none; }
  .frame-chip:hover { transform: none; }
}