/* ============================================================
   四季指南 · 共享样式 /assets/site.css
   四季路线手册：海报层 + 手册层，折线短路径母题
   ============================================================ */

:root {
  /* 品牌基色 */
  --ink: #111310;
  --paper: #F6F4EE;
  --moss: #1F3D2B;
  --deep: #0C120E;
  /* 四季 */
  --spring: #9CC069;
  --apricot: #F2D7B6;
  --lake: #2F7FA6;
  --orange: #F26A2E;
  --amber: #C98B2D;
  --brick: #A6402C;
  --mist: #B9BDB8;
  --frost: #E8EDEA;
  --wash: #EFEBE1;
  --muted: #5C6760;

  /* 字体 */
  --font-display: "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "Songti SC", "Source Han Serif SC", "Noto Serif SC", SimSun, Georgia, serif;
  --font-mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;

  /* 度量 */
  --container: 1180px;
  --gutter: clamp(16px, 3.2vw, 40px);
  --line: 2px;
  --shadow-hard: 6px 6px 0 var(--ink);
  --shadow-hard-sm: 4px 4px 0 var(--ink);
  --ease: cubic-bezier(.2, .7, .3, 1);
}

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

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

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd, address {
  margin: 0;
}

ul, ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

img, svg, video {
  display: block;
  max-width: 100%;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

a { color: inherit; }

table { border-collapse: collapse; }

/* ---------- 基础排版 ---------- */
html, body { min-height: 100%; }

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.06;
}

:where(a, button, [tabindex]):focus-visible {
  outline: 3px solid var(--orange);
  outline-offset: 3px;
}

.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;
}

.skip-link {
  position: absolute;
  top: -100px;
  left: var(--gutter);
  z-index: 200;
  padding: 10px 16px;
  background: var(--moss);
  color: var(--paper);
  border: var(--line) solid var(--ink);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: .9rem;
  text-decoration: none;
  transition: top .16s var(--ease);
}

.skip-link:focus {
  top: 8px;
}

/* ---------- 布局工具 ---------- */
.wrap {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section {
  padding-block: clamp(40px, 7vw, 88px);
}

.section-head {
  display: grid;
  gap: clamp(10px, 1.6vw, 18px);
  margin-bottom: clamp(22px, 3.4vw, 40px);
  max-width: 46ch;
}

.section-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.75rem, 4.4vw, 3.25rem);
  letter-spacing: -0.02em;
  line-height: 0.98;
  text-wrap: balance;
}

.section-lede {
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--muted);
  max-width: 40ch;
}

.display {
  font-family: var(--font-display);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 0.95;
  text-wrap: balance;
}

.display--hero {
  font-size: clamp(2.6rem, 9vw, 7.5rem);
}

.display--section {
  font-size: clamp(1.75rem, 4.4vw, 3.25rem);
}

.coord {
  --coord-dot: var(--moss);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .16em;
  color: var(--moss);
}

.coord::before {
  content: "";
  width: 8px;
  height: 8px;
  background: var(--coord-dot);
  flex: none;
}

.coord--spring { --coord-dot: var(--spring); }
.coord--summer { --coord-dot: var(--lake); }
.coord--autumn { --coord-dot: var(--amber); }
.coord--winter { --coord-dot: var(--mist); }

.mono {
  font-family: var(--font-mono);
  letter-spacing: .04em;
  font-size: .9em;
}

.muted { color: var(--muted); }

.lede {
  font-size: clamp(1rem, 1.4vw, 1.12rem);
  color: var(--muted);
  max-width: 44ch;
}

.path-rule {
  position: relative;
  height: var(--line);
  background: var(--ink);
  margin-block: clamp(24px, 4vw, 48px);
}

.path-rule::after {
  content: "";
  position: absolute;
  right: 0;
  top: -5px;
  width: 10px;
  height: 10px;
  border-top: var(--line) solid var(--ink);
  border-right: var(--line) solid var(--ink);
  transform: rotate(45deg);
  transition: right .16s var(--ease);
}

.path-rule:hover::after { right: 8px; }

.hr-rule {
  height: var(--line);
  background: var(--ink);
  margin-block: clamp(20px, 3vw, 36px);
  opacity: .9;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 18px;
  border: var(--line) solid var(--ink);
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: .95rem;
  line-height: 1.2;
  letter-spacing: .01em;
  text-decoration: none;
  box-shadow: var(--shadow-hard-sm);
  transition: transform .16s var(--ease), box-shadow .16s var(--ease), background-color .12s var(--ease), color .12s var(--ease);
}

.btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-hard);
}

.btn:active {
  transform: translate(2px, 2px);
  box-shadow: 0 0 0 var(--ink);
}

.btn--cta {
  background: var(--orange);
  color: #151210;
}

.btn--solid {
  background: var(--moss);
  color: var(--paper);
}

.btn--ghost {
  background: transparent;
  box-shadow: none;
}

.btn--ghost:hover {
  background: var(--frost);
  box-shadow: var(--shadow-hard-sm);
  transform: translate(-2px, -2px);
}

.btn--sm {
  padding: 8px 12px;
  font-size: .82rem;
  box-shadow: 3px 3px 0 var(--ink);
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  border-top: var(--line) solid var(--ink);
  border-bottom: var(--line) solid var(--ink);
  background: var(--wash);
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: 10px;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
}

.breadcrumb-item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb-link {
  color: var(--moss);
  text-decoration: none;
  border-bottom: var(--line) solid transparent;
  transition: border-color .16s var(--ease), color .12s var(--ease);
}

.breadcrumb-link:hover {
  color: var(--ink);
  border-bottom-color: var(--orange);
}

.breadcrumb-sep {
  color: var(--mist);
}

.breadcrumb-current {
  color: var(--ink);
}

/* ---------- 正文 ---------- */
.prose {
  max-width: 68ch;
}

.prose p {
  margin-block: 0 1.2em;
}

.prose h2,
.prose h3 {
  margin-block: 1.6em .6em;
}

.prose h2 { font-size: clamp(1.4rem, 2.4vw, 1.9rem); }
.prose h3 { font-size: clamp(1.1rem, 1.7vw, 1.3rem); }

.prose ul {
  list-style: square;
  padding-left: 1.2em;
  margin-block: 0 1.2em;
}

.prose li { margin-block: .35em; }

.prose a {
  color: var(--moss);
  text-decoration: none;
  border-bottom: var(--line) solid var(--spring);
}

.prose a:hover {
  border-bottom-color: var(--orange);
}

/* ---------- 网格 ---------- */
.grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 32px);
}

.grid--12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.col-4 { grid-column: span 4; }
.col-5 { grid-column: span 5; }
.col-6 { grid-column: span 6; }
.col-7 { grid-column: span 7; }
.col-8 { grid-column: span 8; }
.col-12 { grid-column: span 12; }

/* ---------- 卡片 ---------- */
.card {
  position: relative;
  border: var(--line) solid var(--ink);
  background: var(--paper);
  padding: clamp(16px, 2.4vw, 26px);
  box-shadow: var(--shadow-hard);
  transition: transform .16s var(--ease), box-shadow .16s var(--ease), background-color .12s var(--ease);
}

.card:hover {
  transform: translate(-2px, -2px);
  box-shadow: 8px 8px 0 var(--ink);
}

.card-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.15rem;
  letter-spacing: -0.01em;
  line-height: 1.2;
}

.card-meta {
  display: inline-block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .12em;
  color: var(--moss);
}

.card-body {
  margin-top: 10px;
  font-size: .95rem;
  color: var(--muted);
}

/* ---------- 差异标签 / 图例 ---------- */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 2px 8px;
  border: var(--line) solid var(--ink);
  background: var(--paper);
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  line-height: 1.6;
  white-space: nowrap;
}

.chip--add { background: var(--spring); color: var(--ink); }
.chip--change { background: var(--amber); color: var(--ink); }
.chip--remove { background: var(--brick); color: var(--paper); }

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  padding: 12px 14px;
  border: var(--line) solid var(--ink);
  background: var(--frost);
}

.legend-item {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .08em;
  color: var(--ink);
}

.legend-swatch {
  width: 12px;
  height: 12px;
  border: var(--line) solid var(--ink);
  background: var(--mist);
  flex: none;
}

.legend-swatch--spring { background: var(--spring); }
.legend-swatch--summer { background: var(--lake); }
.legend-swatch--autumn { background: var(--amber); }
.legend-swatch--winter { background: var(--mist); }
.legend-swatch--moss { background: var(--moss); }
.legend-swatch--orange { background: var(--orange); }

/* ---------- 对照表 ---------- */
.matrix-wrap {
  border: var(--line) solid var(--ink);
  background: var(--paper);
  box-shadow: var(--shadow-hard);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.matrix {
  width: 100%;
  min-width: 560px;
  font-size: .95rem;
}

.matrix caption {
  padding: 12px 14px;
  text-align: left;
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .12em;
  color: var(--moss);
  border-bottom: var(--line) solid var(--ink);
}

.matrix th,
.matrix td {
  padding: 11px 14px;
  text-align: left;
  border-bottom: 1px solid rgba(17, 19, 16, .18);
  vertical-align: top;
}

.matrix thead th {
  background: var(--frost);
  font-family: var(--font-mono);
  font-size: .74rem;
  letter-spacing: .1em;
  font-weight: 600;
  border-bottom: var(--line) solid var(--ink);
}

.matrix tbody tr:nth-child(even) { background: var(--wash); }
.matrix tbody tr:hover { background: var(--apricot); }

/* ---------- 提示条 ---------- */
.note-strip {
  border: var(--line) solid var(--ink);
  border-left: 8px solid var(--orange);
  background: var(--frost);
  padding: 14px 16px;
  font-size: .95rem;
}

.note-strip--warn {
  border-left-color: var(--brick);
  background: #F7EEE9;
}

/* ---------- 步骤 ---------- */
.step-list {
  display: grid;
  gap: 0;
  border-top: var(--line) solid var(--ink);
}

.step {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 14px;
  padding-block: 16px;
  border-bottom: var(--line) solid var(--ink);
  transition: background-color .12s var(--ease);
}

.step:hover { background: var(--frost); }

.step-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  background: var(--moss);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: .8rem;
  letter-spacing: .06em;
}

.step-body { min-width: 0; }

.step-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.02rem;
  letter-spacing: -0.01em;
}

/* ---------- 图片容器 ---------- */
.media-frame {
  position: relative;
  border: var(--line) solid var(--ink);
  background: var(--frost);
  box-shadow: var(--shadow-hard);
  overflow: hidden;
  aspect-ratio: 4 / 3;
  border-top: 8px solid var(--moss);
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }

.media-frame--spring { border-top-color: var(--spring); background: var(--apricot); }
.media-frame--summer { border-top-color: var(--lake); background: var(--frost); }
.media-frame--autumn { border-top-color: var(--amber); background: var(--wash); }
.media-frame--winter { border-top-color: var(--mist); background: var(--frost); }

/* ---------- 复制交互 ---------- */
[data-copy] {
  cursor: copy;
  transition: background-color .12s var(--ease), color .12s var(--ease);
}

[data-copy].is-copied {
  background: var(--spring);
  color: var(--ink);
}

/* ============================================================
   页头
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: var(--paper);
  border-bottom: var(--line) solid var(--ink);
}

.header-rail {
  height: 4px;
  background: linear-gradient(90deg,
      var(--moss) 0 40%,
      var(--spring) 40% 55%,
      var(--lake) 55% 70%,
      var(--amber) 70% 85%,
      var(--mist) 85% 100%);
}

.header-inner {
  position: relative;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
  min-height: 72px;
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding: 10px var(--gutter);
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
  color: var(--ink);
  flex: none;
}

.brand-mark {
  width: 30px;
  height: 26px;
  flex: none;
  background: var(--moss);
  clip-path: polygon(0 100%, 62% 100%, 62% 52%, 100% 52%, 100% 30%, 44% 30%, 44% 74%, 0 74%);
  transition: background-color .12s var(--ease), transform .16s var(--ease);
}

.brand:hover .brand-mark,
.brand:focus-visible .brand-mark {
  background: var(--summer-blue, var(--lake));
  transform: translateX(2px);
}

.brand-mark--invert {
  background: var(--spring);
}

.brand-text {
  display: flex;
  flex-direction: column;
  gap: 3px;
  line-height: 1;
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.16rem;
  letter-spacing: -0.01em;
}

.brand-tag {
  font-family: var(--font-mono);
  font-size: .64rem;
  letter-spacing: .18em;
  color: var(--moss);
}

/* 导航 */
.site-nav {
  justify-self: end;
  min-width: 0;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav-item { display: block; }

.nav-link {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 8px 10px;
  border: var(--line) solid transparent;
  color: var(--ink);
  text-decoration: none;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(.82rem, .9vw, .95rem);
  line-height: 1.2;
  letter-spacing: -0.01em;
  transition: background-color .12s var(--ease), border-color .12s var(--ease), color .12s var(--ease);
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 10px;
  right: 10px;
  bottom: 3px;
  height: var(--line);
  background: var(--ink);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .16s var(--ease);
}

.nav-link:hover {
  background: var(--frost);
  border-color: var(--ink);
}

.nav-link:hover::after,
.nav-link:focus-visible::after {
  transform: scaleX(1);
}

.nav-num {
  font-family: var(--font-mono);
  font-size: .62rem;
  letter-spacing: .06em;
  color: var(--moss);
  opacity: .6;
}

.nav-link[aria-current="page"] {
  background: var(--moss);
  border-color: var(--moss);
  color: var(--paper);
}

.nav-link[aria-current="page"] .nav-num {
  color: var(--spring);
  opacity: 1;
}

.nav-link[aria-current="page"]::after {
  display: none;
}

/* 工具区 */
.utility {
  display: flex;
  align-items: center;
  gap: 10px;
  justify-self: end;
}

.search-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  max-width: 230px;
  padding: 8px 12px;
  border: var(--line) solid var(--ink);
  background: var(--frost);
  color: #3E4B43;
  text-decoration: none;
  font-family: var(--font-body);
  font-size: .8rem;
  line-height: 1.4;
  transition: background-color .12s var(--ease), transform .16s var(--ease), box-shadow .16s var(--ease);
}

.search-link::before {
  content: "";
  width: 11px;
  height: 11px;
  flex: none;
  border: var(--line) solid var(--moss);
  border-radius: 50%;
}

.search-link:hover {
  background: var(--paper);
  transform: translate(-2px, -2px);
  box-shadow: 3px 3px 0 var(--ink);
}

.search-hint {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.header-cta { white-space: nowrap; }

/* 移动按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 4px;
  width: 44px;
  height: 40px;
  border: var(--line) solid var(--ink);
  background: var(--paper);
  box-shadow: 3px 3px 0 var(--ink);
  transition: transform .16s var(--ease), background-color .12s var(--ease);
}

.nav-toggle:hover { background: var(--frost); }
.nav-toggle:active { transform: translate(2px, 2px); box-shadow: 0 0 0 var(--ink); }

.nav-toggle-bar {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--ink);
  transition: transform .16s var(--ease), opacity .12s var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* 阅读进度 */
.read-rail {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 3px;
  pointer-events: none;
  background: transparent;
}

.read-rail-fill {
  display: block;
  height: 100%;
  width: 100%;
  background: var(--spring);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform .12s linear;
}

/* 移动端快捷路径条 */
.path-bar {
  display: none;
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 70;
  grid-template-columns: repeat(4, 1fr);
  background: var(--deep);
  border-top: var(--line) solid var(--ink);
}

.path-bar-link {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 11px 4px calc(11px + env(safe-area-inset-bottom));
  border-top: 3px solid var(--mist);
  color: var(--frost);
  text-decoration: none;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: .76rem;
  letter-spacing: .01em;
  transition: background-color .12s var(--ease), color .12s var(--ease);
}

.path-bar-link:nth-child(1) { border-top-color: var(--spring); }
.path-bar-link:nth-child(2) { border-top-color: var(--lake); }
.path-bar-link:nth-child(3) { border-top-color: var(--amber); }
.path-bar-link:nth-child(4) { border-top-color: var(--mist); }

.path-bar-link:hover,
.path-bar-link[aria-current="page"] {
  background: var(--moss);
  color: var(--paper);
}

.path-bar-label { white-space: nowrap; }

/* ============================================================
   页脚
   ============================================================ */
.site-footer {
  background: var(--deep);
  color: var(--frost);
  border-top: var(--line) solid var(--ink);
}

.footer-rail {
  height: 4px;
  background: linear-gradient(90deg,
      var(--spring) 0 25%,
      var(--lake) 25% 50%,
      var(--amber) 50% 75%,
      var(--mist) 75% 100%);
}

.footer-inner {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding: clamp(30px, 5vw, 60px) var(--gutter) 22px;
}

.footer-brand {
  display: grid;
  gap: 8px;
  padding-bottom: clamp(20px, 3vw, 34px);
  border-bottom: var(--line) solid rgba(246, 244, 238, .22);
}

.footer-brand-link {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
  color: var(--paper);
}

.footer-brand-name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.35rem;
  letter-spacing: -0.01em;
}

.footer-brand-tag {
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .16em;
  color: var(--mist);
}

.footer-coord {
  font-family: var(--font-mono);
  font-size: .68rem;
  letter-spacing: .12em;
  color: var(--spring);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(20px, 3vw, 36px);
  padding-block: clamp(24px, 3.6vw, 40px);
}

.footer-col { min-width: 0; }

.footer-col:nth-child(1) { grid-column: 1 / span 4; --col-dot: var(--spring); }
.footer-col:nth-child(2) { grid-column: 5 / span 3; padding-top: 26px; --col-dot: var(--amber); }
.footer-col:nth-child(3) { grid-column: 8 / span 5; padding-top: 10px; --col-dot: var(--lake); }
.footer-col:nth-child(4) { grid-column: 2 / span 8; padding-top: 30px; --col-dot: var(--mist); }

.footer-col-title {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: .7rem;
  font-weight: 500;
  letter-spacing: .2em;
  color: var(--mist);
}

.footer-col-title::before {
  content: "";
  width: 8px;
  height: 8px;
  flex: none;
  background: var(--col-dot, var(--mist));
}

.footer-list {
  display: grid;
  gap: 6px;
}

.footer-item { display: block; }

.footer-link {
  display: inline-block;
  color: var(--frost);
  text-decoration: none;
  font-family: var(--font-body);
  font-size: .92rem;
  line-height: 1.6;
  border-bottom: var(--line) solid transparent;
  transition: color .12s var(--ease), border-color .16s var(--ease), transform .16s var(--ease);
}

.footer-link:hover {
  color: var(--paper);
  border-bottom-color: var(--spring);
  transform: translateX(2px);
}

.footer-link--static {
  color: var(--mist);
  cursor: default;
  font-family: var(--font-mono);
  font-size: .82rem;
  letter-spacing: .02em;
}

.footer-link--static:hover {
  color: var(--mist);
  border-bottom-color: transparent;
  transform: none;
}

.footer-address {
  font-style: normal;
  font-size: .92rem;
  line-height: 1.7;
  color: var(--frost);
  max-width: 32ch;
}

.footer-note {
  padding: 16px 0 18px;
  border-top: var(--line) solid rgba(246, 244, 238, .22);
  font-size: .84rem;
  line-height: 1.7;
  color: var(--mist);
  max-width: 60ch;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 22px;
  padding-top: 14px;
  border-top: var(--line) solid rgba(246, 244, 238, .22);
}

.footer-legal,
.footer-copy {
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .1em;
  color: var(--mist);
}

.to-top {
  margin-left: auto;
  padding: 7px 14px;
  border: var(--line) solid rgba(246, 244, 238, .45);
  background: transparent;
  color: var(--frost);
  font-family: var(--font-mono);
  font-size: .72rem;
  letter-spacing: .12em;
  transition: background-color .12s var(--ease), color .12s var(--ease), border-color .12s var(--ease);
}

.to-top:hover {
  background: var(--orange);
  border-color: var(--orange);
  color: #151210;
}

.site-footer :where(a, button):focus-visible {
  outline-color: var(--spring);
}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1240px) {
  .search-hint { display: none; }

  .search-link {
    width: 40px;
    height: 40px;
    padding: 0;
    justify-content: center;
  }
}

@media (max-width: 1000px) {
  body { padding-bottom: 60px; }

  .path-bar { display: grid; }

  .header-inner {
    grid-template-columns: 1fr auto;
    min-height: 64px;
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    justify-self: stretch;
    display: none;
    background: var(--paper);
    border-bottom: var(--line) solid var(--ink);
    box-shadow: 0 6px 0 rgba(17, 19, 16, .14);
    padding: 14px var(--gutter) 20px;
  }

  .site-header[data-open] .site-nav { display: block; }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
  }

  .nav-link {
    width: 100%;
    justify-content: space-between;
    padding: 12px 14px;
    border: var(--line) solid var(--ink);
    background: var(--paper);
    font-size: 1rem;
  }

  .nav-link::after { display: none; }

  .nav-item:nth-child(1) .nav-link { border-left: 8px solid var(--spring); }
  .nav-item:nth-child(2) .nav-link { border-left: 8px solid var(--lake); }
  .nav-item:nth-child(3) .nav-link { border-left: 8px solid var(--amber); }
  .nav-item:nth-child(4) .nav-link { border-left: 8px solid var(--mist); }
  .nav-item:nth-child(5) .nav-link { border-left: 8px solid var(--moss); }
  .nav-item:nth-child(6) .nav-link { border-left: 8px solid var(--brick); }

  .nav-num { color: var(--moss); opacity: .7; }

  .nav-toggle { display: inline-flex; }

  .grid--12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }

  .col-4,
  .col-5 { grid-column: span 3; }

  .col-6,
  .col-7,
  .col-8 { grid-column: span 6; }

  .footer-col:nth-child(1) { grid-column: 1 / span 6; }
  .footer-col:nth-child(2) { grid-column: 1 / span 3; padding-top: 0; }
  .footer-col:nth-child(3) { grid-column: 4 / span 3; padding-top: 0; }
  .footer-col:nth-child(4) { grid-column: 1 / span 6; padding-top: 0; }
}

@media (max-width: 700px) {
  .grid--3 { grid-template-columns: 1fr; }

  .footer-grid { gap: 22px; }

  .footer-col:nth-child(1),
  .footer-col:nth-child(2),
  .footer-col:nth-child(3),
  .footer-col:nth-child(4) {
    grid-column: 1 / -1;
  }

  .footer-bottom { gap: 10px; }

  .to-top { margin-left: 0; }

  .matrix { font-size: .9rem; }
}

@media (max-width: 600px) {
  body { font-size: 16px; }

  .grid--12 { grid-template-columns: 1fr; }
  .grid--2 { grid-template-columns: 1fr; }

  .col-4,
  .col-5,
  .col-6,
  .col-7,
  .col-8,
  .col-12 { grid-column: auto; }

  .brand-mark { width: 26px; height: 22px; }
  .brand-name { font-size: 1.02rem; }
  .brand-tag { font-size: .58rem; letter-spacing: .12em; }

  .header-cta { padding: 7px 10px; font-size: .74rem; }
  .search-link { width: 36px; height: 36px; }
  .nav-toggle { width: 40px; height: 36px; }
}

@media (max-width: 400px) {
  .brand-tag { display: none; }
  .path-bar-label { font-size: .7rem; }
}

/* ---------- 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }

  .btn:hover,
  .card:hover,
  .footer-link:hover,
  .brand:hover .brand-mark,
  .search-link:hover,
  .path-rule:hover::after {
    transform: none;
  }
}