/* ==========================================================================
   全站共享样式 /assets/site.css
   骨架：岩褐暗区 + 沙白亮区 + 沙金细线 + 湖青状态 + 石榴红关键入口
   ========================================================================== */

/* ---------- 0. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd, fieldset { 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; }
table { border-collapse: collapse; width: 100%; }

/* ---------- 1. 设计变量 ---------- */
:root {
  --rock: #3E2F23;
  --rock-2: #4A3A2C;
  --sand: #C9A24B;
  --sand-lite: #E4CE97;
  --lake: #2E7E7B;
  --lake-deep: #1D5754;
  --pome: #C0392B;
  --paper: #F3EBDC;
  --ink: #221912;
  --clay: #8A6F52;
  --stone: #6E7A72;

  --hair-col: rgba(201, 162, 75, .35);
  --hair: 1px solid var(--hair-col);
  --hair-strong: 1px solid rgba(201, 162, 75, .62);
  --hair-dark: 1px solid rgba(243, 235, 220, .16);
  --dash: 1px dashed rgba(201, 162, 75, .38);

  --cut-shape: polygon(0 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%);
  --cut-lg: polygon(0 0, 100% 0, 100% calc(100% - 14px), calc(100% - 14px) 100%, 0 100%);

  --ease: cubic-bezier(.22, .61, .36, 1);
  --dur: 220ms;
  --dur-slow: 260ms;

  --pad: 72px;
  --maxw: 1440px;

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

@media (max-width: 1024px) { :root { --pad: 36px; } }
@media (max-width: 640px)  { :root { --pad: 20px; } }

/* ---------- 2. 中文排版与基础元素 ---------- */
body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-weight: 500;
  font-size: 1.02rem;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4 {
  font-weight: 900;
  letter-spacing: -.02em;
  line-height: 1.25;
}

h1 { font-size: clamp(1.6rem, 3vw, 2.4rem); }
h2 { font-size: 1.15rem; letter-spacing: 0; }
h3 { font-size: 1.05rem; letter-spacing: 0; }

p + p { margin-top: 1.2em; }

.mono {
  font-family: var(--mono);
  letter-spacing: .04em;
  font-weight: 500;
  font-variant-numeric: tabular-nums;
}

.u-num {
  font-family: var(--mono);
  letter-spacing: .04em;
  font-weight: 700;
  color: var(--clay);
}

a.link {
  color: var(--lake-deep);
  text-decoration: none;
  border-bottom: 1px solid var(--hair-col);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
a.link:hover { color: var(--pome); border-color: var(--pome); }

:focus-visible {
  outline: 2px solid var(--lake);
  outline-offset: 2px;
}
.site-header :focus-visible,
.site-footer :focus-visible,
.section--dark :focus-visible {
  outline-color: var(--sand-lite);
}

/* ---------- 3. 布局容器与栅格 ---------- */
.shell {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--pad);
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 24px;
}

.grid--split5-7 { grid-template-columns: repeat(12, minmax(0, 1fr)); }
.grid--split5-7 > .grid__a { grid-column: 1 / span 5; }
.grid--split5-7 > .grid__b { grid-column: 6 / span 7; }

.grid--main-aside > .grid__main { grid-column: 1 / span 7; }
.grid--main-aside > .grid__aside { grid-column: 9 / span 3; }

.stack > * + * { margin-top: 20px; }

@media (max-width: 1024px) {
  .grid--split5-7 > .grid__a,
  .grid--split5-7 > .grid__b,
  .grid--main-aside > .grid__main,
  .grid--main-aside > .grid__aside { grid-column: 1 / -1; }
}

/* ---------- 4. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  font-family: var(--sans);
  font-weight: 900;
  font-size: .88rem;
  letter-spacing: .06em;
  line-height: 1.3;
  text-decoration: none;
  border: 1px solid transparent;
  background: transparent;
  color: inherit;
  clip-path: var(--cut-shape);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease),
              border-color var(--dur) var(--ease);
}

.btn--entry { background: var(--sand); color: var(--ink); }
.btn--entry:hover { background: var(--sand-lite); }

.btn--ghost { border-color: rgba(201, 162, 75, .55); color: var(--sand-lite); }
.btn--ghost:hover { background: rgba(201, 162, 75, .16); color: var(--paper); }

.btn--solid { background: var(--lake); color: #fff; }
.btn--solid:hover { background: var(--lake-deep); }

.btn--alert { background: var(--pome); color: #fff; }
.btn--alert:hover { background: #A52F23; }

.btn--block { display: flex; width: 100%; }

.btn--line { border-color: var(--hair-col); color: var(--lake-deep); }
.btn--line:hover { background: rgba(46, 126, 123, .1); border-color: var(--lake); }

/* ---------- 5. 跳转链接 ---------- */
.skip-link {
  position: absolute;
  top: -100px;
  left: 12px;
  z-index: 300;
  padding: 10px 18px;
  background: var(--sand);
  color: var(--ink);
  font-weight: 900;
  text-decoration: none;
  clip-path: var(--cut-shape);
  transition: top var(--dur) var(--ease);
}
.skip-link:focus { top: 10px; }

/* ---------- 6. 页头 ---------- */
.site-header {
  position: relative;
  z-index: 80;
  background: var(--rock);
  color: var(--paper);
}

/* 6.1 索引带 */
.index-band {
  position: sticky;
  top: 0;
  z-index: 90;
  background: var(--rock);
  border-bottom: var(--hair);
}

.index-band__inner {
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--pad);
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  font-family: var(--mono);
  font-size: .7rem;
  letter-spacing: .12em;
  line-height: 1;
}

.index-band__path { display: flex; align-items: center; gap: 8px; margin: 0; }
.index-band__key { color: var(--sand); }
.index-band__sep { color: var(--clay); }

.index-band__now {
  position: relative;
  color: var(--paper);
  padding-bottom: 2px;
}
.index-band__now::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -3px;
  height: 1px;
  background: var(--lake);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur-slow) var(--ease);
}
.index-band__now.is-live::after { transform: scaleX(1); }

.index-band__meta {
  margin: 0;
  color: var(--clay);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.scroll-progress {
  display: block;
  height: 1px;
  width: 100%;
  background: var(--lake);
  transform: scaleX(0);
  transform-origin: left center;
}

/* 6.2 刊头 */
.masthead {
  position: relative;
  overflow: hidden;
  background: var(--rock);
}

.masthead::before {
  content: "";
  position: absolute;
  inset: -24px;
  pointer-events: none;
  background-image: radial-gradient(rgba(201, 162, 75, .26) 1px, transparent 1.4px);
  background-size: 9px 9px;
  opacity: .32;
  animation: halftone-drift 24s ease-in-out infinite alternate;
}

@keyframes halftone-drift {
  from { transform: translate3d(0, 0, 0); }
  to   { transform: translate3d(-9px, -9px, 0); }
}

.masthead__inner {
  position: relative;
  z-index: 1;
  max-width: var(--maxw);
  margin-inline: auto;
  padding: 24px var(--pad) 16px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 18px;
}

.masthead__meta {
  margin: 0;
  font-family: var(--mono);
  font-size: .66rem;
  letter-spacing: .22em;
  color: var(--clay);
  justify-self: start;
}

.masthead__center { justify-self: center; text-align: center; }

.masthead__brand {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  text-decoration: none;
  color: inherit;
}

.masthead__mark {
  font-family: var(--mono);
  font-size: .68rem;
  letter-spacing: .38em;
  color: var(--sand);
  text-indent: .38em;
}

.masthead__name {
  font-size: clamp(1.5rem, 2.8vw, 2.15rem);
  font-weight: 900;
  letter-spacing: .06em;
  line-height: 1.15;
  color: var(--paper);
  transition: color var(--dur) var(--ease);
}
.masthead__brand:hover .masthead__name { color: var(--sand-lite); }

.masthead__tagline {
  margin-top: 4px;
  font-family: var(--mono);
  font-size: .68rem;
  letter-spacing: .2em;
  color: var(--clay);
}

.masthead__actions {
  justify-self: end;
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav-toggle { display: none; }
.nav-toggle__close { display: none; }
.nav-toggle[aria-expanded="true"] .nav-toggle__open { display: none; }
.nav-toggle[aria-expanded="true"] .nav-toggle__close { display: inline; }

/* 6.3 核心索引面板 */
.quick-index { position: relative; z-index: 1; }
.quick-index[hidden] { display: none; }

.quick-index__inner {
  max-width: var(--maxw);
  margin-inline: auto;
  padding: 0 var(--pad) 20px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  background: var(--hair-col);
  border-top: 1px solid var(--hair-col);
}

.quick-index__item {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-rows: auto auto;
  gap: 2px 12px;
  padding: 14px 16px;
  background: var(--rock);
  text-decoration: none;
  color: var(--paper);
  border-left: 2px solid transparent;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease),
              color var(--dur) var(--ease);
  animation: quickFade var(--dur-slow) var(--ease) both;
}
.quick-index__item:nth-child(2) { animation-delay: 60ms; }
.quick-index__item:nth-child(3) { animation-delay: 120ms; }

.quick-index__item:hover,
.quick-index__item:focus-visible {
  background: var(--rock-2);
  border-left-color: var(--pome);
}

@keyframes quickFade {
  from { opacity: 0; transform: translateY(-6px); }
  to   { opacity: 1; transform: none; }
}

.quick-index__no {
  grid-row: 1 / span 2;
  align-self: center;
  font-family: var(--mono);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--sand);
}

.quick-index__label { font-weight: 900; font-size: .96rem; letter-spacing: .04em; }

.quick-index__path {
  font-family: var(--mono);
  font-size: .68rem;
  color: var(--clay);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* 6.4 刊头下栏目 */
.site-nav {
  background: var(--rock);
  border-top: var(--hair);
  border-bottom: var(--hair);
  counter-reset: navidx;
}

.site-nav__list {
  max-width: var(--maxw);
  margin-inline: auto;
  padding: 0 var(--pad);
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0 4px;
}

.site-nav__item { counter-increment: navidx; }

.site-nav__link {
  position: relative;
  display: block;
  padding: 12px 14px;
  font-size: .92rem;
  font-weight: 500;
  letter-spacing: .08em;
  color: var(--sand-lite);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}

.site-nav__link::before {
  content: counter(navidx, decimal-leading-zero);
  font-family: var(--mono);
  font-size: .6rem;
  letter-spacing: .04em;
  color: var(--clay);
  margin-right: 8px;
  vertical-align: 2px;
}

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 8px;
  height: 2px;
  background: var(--sand);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform var(--dur) var(--ease), background var(--dur) var(--ease);
}

.site-nav__link:hover { color: var(--paper); }
.site-nav__link:hover::after { background: var(--lake); transform: scaleX(1); }

.site-nav__link[aria-current="page"] { color: var(--paper); font-weight: 900; }
.site-nav__link[aria-current="page"]::before { color: var(--sand); }
.site-nav__link[aria-current="page"]::after { background: var(--sand); transform: scaleX(1); }

.site-nav__link[aria-current="page"]:hover::after { background: var(--sand); }

/* ---------- 7. 页脚 ---------- */
.site-footer {
  background: var(--ink);
  color: var(--paper);
  border-top: var(--hair-strong);
  font-size: .92rem;
}

.site-footer__inner {
  max-width: var(--maxw);
  margin-inline: auto;
  padding: 56px var(--pad) 32px;
  display: grid;
  grid-template-columns: minmax(220px, 1fr) 3fr;
  gap: 40px;
}

.site-footer__mark {
  margin: 0;
  font-family: var(--mono);
  font-size: .68rem;
  letter-spacing: .22em;
  color: var(--sand);
}

.site-footer__name {
  margin-top: 8px;
  font-size: 1.35rem;
  font-weight: 900;
  letter-spacing: .06em;
  color: var(--paper);
}

.site-footer__tagline {
  margin-top: 6px;
  font-family: var(--mono);
  font-size: .68rem;
  letter-spacing: .16em;
  color: var(--clay);
}

.site-footer__nav {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 28px;
}

.footer-col__title {
  font-size: .74rem;
  font-weight: 900;
  letter-spacing: .16em;
  color: var(--sand);
  padding-bottom: 10px;
  margin-bottom: 12px;
  border-bottom: var(--hair);
}

.footer-col__list { display: grid; gap: 9px; }

.footer-link {
  display: inline-block;
  color: rgba(243, 235, 220, .78);
  text-decoration: none;
  font-size: .9rem;
  transition: color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.footer-link:hover { color: var(--sand-lite); transform: translateX(3px); }

.site-footer__contact {
  max-width: var(--maxw);
  margin-inline: auto;
  padding: 22px var(--pad);
  border-top: var(--hair-dark);
  display: grid;
  gap: 6px;
}

.site-footer__line { margin: 0; font-size: .84rem; color: rgba(243, 235, 220, .72); }
.site-footer__line .mono { color: var(--sand-lite); }
.site-footer__addr { margin: 0; font-size: .8rem; color: var(--clay); }

.site-footer__legal {
  max-width: var(--maxw);
  margin-inline: auto;
  padding: 14px var(--pad) 26px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 24px;
  justify-content: space-between;
  font-size: .74rem;
  color: var(--stone);
  border-top: var(--hair-dark);
}

/* ---------- 8. 正文基础构件 ---------- */
.page-head { padding: 48px 0 32px; }
.page-head__kicker {
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: .2em;
  color: var(--clay);
  margin-bottom: 12px;
}
.page-head__title { margin-bottom: 12px; }
.lede {
  font-size: 1.05rem;
  color: var(--clay);
  max-width: 62ch;
}

.crumbs { padding: 18px 0 0; }
.crumbs__list { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.crumbs__item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: .06em;
  color: var(--clay);
}
.crumbs__item + .crumbs__item::before {
  content: "/";
  color: var(--sand);
  font-family: var(--mono);
}
.crumbs__link {
  color: var(--clay);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.crumbs__link:hover { color: var(--lake-deep); border-color: var(--lake); }

.section { padding: 56px 0; border-top: var(--hair); }
.section--dense { padding: 36px 0; }
.section--dark { background: var(--rock); color: var(--paper); border-top: 0; }
.section--paper { background: var(--paper); }
.section--tint { background: rgba(138, 111, 82, .07); }
.section__title { margin-bottom: 18px; }

.panel {
  position: relative;
  padding: 24px;
  border: var(--hair);
  background: rgba(255, 255, 255, .38);
}
.panel::after {
  content: "";
  position: absolute;
  right: -1px;
  bottom: -1px;
  width: 12px;
  height: 12px;
  background: linear-gradient(to bottom left,
              transparent calc(50% - 1px), var(--hair-col) 50%,
              transparent calc(50% + 1px));
  pointer-events: none;
}

.panel--fill {
  background: var(--rock);
  color: var(--paper);
  border: 0;
  clip-path: var(--cut-lg);
}
.panel--fill::after { display: none; }

.panel--alert {
  border-left: 2px solid var(--pome);
  background: rgba(192, 57, 43, .06);
}
.panel--alert::after { display: none; }

.note {
  font-size: .86rem;
  line-height: 1.75;
  color: var(--clay);
  border-left: 2px solid var(--hair-col);
  padding-left: 14px;
}

.tag {
  display: inline-block;
  padding: 3px 9px;
  font-family: var(--mono);
  font-size: .68rem;
  letter-spacing: .08em;
  color: var(--lake-deep);
  border: 1px solid rgba(46, 126, 123, .45);
  background: rgba(46, 126, 123, .08);
  clip-path: var(--cut-shape);
}
.tag--sand { color: #6B5333; border-color: rgba(201, 162, 75, .6); background: rgba(201, 162, 75, .16); }
.tag--alert { color: #fff; background: var(--pome); border-color: var(--pome); }

.hair { height: 1px; background: var(--hair-col); border: 0; margin: 24px 0; }

/* 编号索引条目 */
.index-list { border-top: var(--hair); }
.index-list__item {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr) auto;
  align-items: baseline;
  gap: 16px;
  padding: 18px 4px;
  border-bottom: var(--hair);
  text-decoration: none;
  color: inherit;
  transition: background var(--dur) var(--ease), padding-left var(--dur) var(--ease);
}
.index-list__item:hover { background: rgba(201, 162, 75, .13); padding-left: 14px; }
.index-list__no {
  font-family: var(--mono);
  font-size: .82rem;
  font-weight: 700;
  color: var(--clay);
}
.index-list__item:hover .index-list__no { color: var(--lake-deep); }
.index-list__title { font-weight: 900; font-size: 1rem; letter-spacing: .02em; }
.index-list__path {
  font-family: var(--mono);
  font-size: .72rem;
  color: var(--clay);
  white-space: nowrap;
}

/* 折叠问答组 */
.fold {
  border: var(--hair);
  background: rgba(255, 255, 255, .4);
}
.fold + .fold { margin-top: -1px; }

.fold__summary {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 16px 18px;
  cursor: pointer;
  font-weight: 900;
  font-size: 1rem;
  list-style: none;
}
.fold__summary::-webkit-details-marker { display: none; }
.fold__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--mono);
  font-size: 1.1rem;
  line-height: 1;
  color: var(--sand);
  transition: transform var(--dur-slow) var(--ease), color var(--dur) var(--ease);
}
.fold[open] > .fold__summary::after { transform: rotate(45deg); color: var(--lake); }

.fold__body {
  padding: 0 18px 20px;
  animation: foldIn var(--dur-slow) var(--ease) both;
}
@keyframes foldIn {
  from { opacity: 0; transform: translateY(-4px); }
  to   { opacity: 1; transform: none; }
}

/* 纯 CSS 终端切换 */
.switcher { display: block; }
.switcher__input {
  position: absolute;
  opacity: 0;
  width: 1px;
  height: 1px;
  overflow: hidden;
}
.switcher__labels {
  display: flex;
  flex-wrap: wrap;
  gap: 1px;
  background: var(--hair-col);
  border: var(--hair);
  margin-bottom: 20px;
}
.switcher__label {
  flex: 1 1 120px;
  padding: 11px 14px;
  text-align: center;
  background: var(--paper);
  cursor: pointer;
  font-weight: 900;
  font-size: .88rem;
  letter-spacing: .06em;
  color: var(--clay);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}
.switcher__label:hover { background: var(--sand-lite); color: var(--ink); }
.switcher__panel { display: none; }

.switcher__input:focus-visible + .switcher__label,
.switcher__labels .switcher__input:focus-visible + .switcher__label {
  outline: 2px solid var(--lake);
  outline-offset: -3px;
}

/* 三个终端：面板按选中项显示 */
.switcher__input--desktop:checked ~ .switcher__labels .switcher__label--desktop,
.switcher__input--android:checked ~ .switcher__labels .switcher__label--android,
.switcher__input--ios:checked ~ .switcher__labels .switcher__label--ios {
  background: var(--rock);
  color: var(--paper);
}
.switcher__input--desktop:checked ~ .switcher__panels .switcher__panel--desktop,
.switcher__input--android:checked ~ .switcher__panels .switcher__panel--android,
.switcher__input--ios:checked ~ .switcher__panels .switcher__panel--ios {
  display: block;
  animation: foldIn var(--dur-slow) var(--ease) both;
}

/* 步骤清单 */
.steps { display: grid; gap: 1px; background: var(--hair-col); border: var(--hair); }
.steps__item {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 16px 18px;
  background: var(--paper);
  cursor: pointer;
}
.steps__box { width: 20px; height: 20px; margin-top: 3px; accent-color: var(--lake); }
.steps__no {
  font-family: var(--mono);
  font-size: .74rem;
  color: var(--clay);
  margin-right: 8px;
}
.steps__text { font-size: .96rem; }
.steps__item:has(.steps__box:checked) { background: rgba(46, 126, 123, .09); }
.steps__item:has(.steps__box:checked) .steps__text { color: var(--lake-deep); }
.steps__bar { height: 3px; background: var(--sand); }

/* 表格 */
.table {
  border: var(--hair);
  font-size: .92rem;
}
.table caption {
  caption-side: top;
  text-align: left;
  padding: 0 0 12px;
  font-family: var(--mono);
  font-size: .72rem;
  letter-spacing: .14em;
  color: var(--clay);
}
.table th,
.table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: var(--hair);
  vertical-align: top;
}
.table thead th {
  background: rgba(62, 47, 35, .07);
  font-weight: 900;
  font-size: .86rem;
  letter-spacing: .04em;
}
.table tbody tr:nth-child(even) { background: rgba(138, 111, 82, .07); }
.table tbody tr:last-child td { border-bottom: 0; }
.table .mono { color: var(--clay); }

/* 图片容器（供页面阶段放图，禁止实景照片与具象插画） */
.figure {
  position: relative;
  margin: 0;
  overflow: hidden;
  background: var(--rock);
  clip-path: var(--cut-lg);
}
.figure > img,
.figure > svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.72) contrast(1.02);
}
.figure--16-9 { aspect-ratio: 16 / 9; }
.figure--4-3 { aspect-ratio: 4 / 3; }
.figure--1-1 { aspect-ratio: 1 / 1; }
.figure--wide { aspect-ratio: 21 / 9; }
.figure--tall { aspect-ratio: 4 / 5; }

.figure__texture {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    radial-gradient(rgba(243, 235, 220, .2) 1px, transparent 1.4px),
    repeating-linear-gradient(0deg, rgba(201, 162, 75, .12) 0 1px, transparent 1px 14px);
  background-size: 8px 8px, 100% 100%;
  opacity: .55;
}

.figure__caption {
  margin-top: 10px;
  font-family: var(--mono);
  font-size: .74rem;
  letter-spacing: .06em;
  color: var(--clay);
}

/* 复制按钮状态 */
[data-copy] { transition: background var(--dur) var(--ease), color var(--dur) var(--ease); }
[data-copy].is-copied { background: var(--lake); color: #fff; border-color: var(--lake); }

/* 显现 */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease);
}
[data-reveal].is-visible { opacity: 1; transform: none; }

/* ---------- 9. 响应式 ---------- */
@media (max-width: 1280px) {
  .site-nav__link { padding: 12px 10px; font-size: .88rem; }
  .site-footer__inner { gap: 32px; }
}

@media (max-width: 1024px) {
  .masthead__meta { display: none; }
  .masthead__inner { grid-template-columns: 1fr auto; }
  .masthead__center { justify-self: start; text-align: left; }
  .masthead__brand { align-items: flex-start; }
  .site-footer__inner { grid-template-columns: 1fr; gap: 32px; }
  .site-footer__nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .quick-index__inner { grid-template-columns: 1fr; }
}

@media (max-width: 900px) {
  .nav-toggle { display: inline-flex; }

  .site-nav { display: none; background: var(--rock-2); }
  .site-nav[data-open] { display: block; animation: navIn var(--dur-slow) var(--ease) both; }

  @keyframes navIn {
    from { opacity: 0; transform: translateY(-6px); }
    to   { opacity: 1; transform: none; }
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    padding: 6px var(--pad) 16px;
    gap: 0;
  }
  .site-nav__item { border-bottom: var(--dash); }
  .site-nav__item:last-child { border-bottom: 0; }
  .site-nav__link { padding: 14px 4px; font-size: 1rem; }
  .site-nav__link::after { left: 4px; right: auto; width: 34px; bottom: 9px; }
}

@media (max-width: 768px) {
  .index-band__meta { display: none; }
  .masthead__inner { grid-template-columns: 1fr; padding-top: 20px; }
  .masthead__center { justify-self: center; text-align: center; }
  .masthead__brand { align-items: center; }
  .masthead__actions { justify-self: center; width: 100%; }
  .masthead__actions .btn { flex: 1 1 auto; }
  .page-head { padding: 32px 0 24px; }
  .section { padding: 40px 0; }
  .index-list__item { grid-template-columns: 40px minmax(0, 1fr); }
  .index-list__path { grid-column: 2 / -1; }
  .site-footer__legal { flex-direction: column; }
}

@media (max-width: 480px) {
  .site-footer__nav { grid-template-columns: 1fr; }
  .quick-index__item { padding: 12px; }
  .panel { padding: 18px; }
  .table { font-size: .86rem; }
  .table th, .table td { padding: 10px 10px; }
}

@media (max-width: 360px) {
  .masthead__name { font-size: 1.35rem; }
  .site-nav__link { padding: 12px 2px; font-size: .94rem; }
}

/* ---------- 10. 动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
  .masthead::before { animation: none; }
  .index-band__now::after { transform: scaleX(1); }
  [data-reveal] { opacity: 1; transform: none; }
}