/* ==========================================================================
   亿万CN生活站 · 共享样式 /assets/site.css
   暖纸 × 深墨蓝 × 暖橙 —— 一本被翻旧的城市生活手册
   ========================================================================== */

:root{
  --ink-900:#0E1A2B;
  --ink-700:#1C2F47;
  --orange-500:#E4681C;
  --orange-300:#F3A15F;
  --sand-500:#C39A2B;
  --sand-200:#E8D9A8;
  --celadon-500:#4F7D69;
  --paper-100:#F5EFE3;
  --paper-200:#EAE1CE;
  --line-300:#C7BCA8;
  --alert-500:#B34234;

  --font-head:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-body:var(--font-head);
  --font-mono:"IBM Plex Mono","JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  --shell:1180px;
  --gutter:clamp(16px,4vw,44px);
  --stack-gap:1rem;
  --sticky-offset:132px;

  --r-sm:3px;
  --r-md:7px;
  --r-full:999px;

  --shadow-1:0 1px 0 rgba(14,26,43,.05), 0 8px 20px -14px rgba(14,26,43,.40);
  --shadow-2:0 2px 0 rgba(14,26,43,.05), 0 20px 44px -28px rgba(14,26,43,.55);

  --ease:cubic-bezier(.2,.7,.3,1);
  --dur:280ms;
}

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

html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:var(--sticky-offset);
}

body{
  margin:0;
  color:var(--ink-900);
  font-family:var(--font-body);
  font-size:1.05rem;
  font-weight:400;
  line-height:1.8;
  background-color:var(--paper-100);
  background-image:
    radial-gradient(1100px 560px at 88% -8%, rgba(196,154,43,.16), transparent 62%),
    radial-gradient(860px 480px at -12% 6%, rgba(79,125,105,.13), transparent 64%),
    linear-gradient(180deg, rgba(234,225,206,.72), rgba(245,239,227,0) 440px);
  background-repeat:no-repeat;
}

img{max-width:100%;height:auto;}
a{color:inherit;text-decoration:none;}
button{font:inherit;}
h1,h2,h3,h4{font-family:var(--font-head);font-weight:900;line-height:1.28;margin:0;}
p{margin:0 0 1rem;}
p:last-child{margin-bottom:0;}
ul,ol{margin:0;}
table{border-collapse:collapse;}

:focus-visible{
  outline:3px solid var(--orange-500);
  outline-offset:2px;
  border-radius:2px;
}

/* ---------- 跳转链接 ---------- */
.yw-skip{
  position:fixed;
  top:.6rem;
  left:.6rem;
  z-index:200;
  padding:.62rem 1.05rem;
  background:var(--ink-900);
  color:var(--paper-100);
  border:2px solid var(--orange-500);
  border-radius:var(--r-sm);
  font-weight:700;
  font-size:.92rem;
  transform:translateY(-180%);
  transition:transform var(--dur) var(--ease);
}
.yw-skip:focus{transform:translateY(0);}

/* ---------- 布局基座 ---------- */
.yw-shell{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.yw-section{padding-block:clamp(40px,6vw,84px);}
.yw-stack > * + *{margin-top:var(--stack-gap);}

.yw-grid{display:grid;gap:clamp(18px,2.6vw,34px);}
.yw-grid--2{grid-template-columns:repeat(2,minmax(0,1fr));}
.yw-grid--3{grid-template-columns:repeat(3,minmax(0,1fr));}
.yw-grid--6-6{grid-template-columns:repeat(2,minmax(0,1fr));}
.yw-grid--7-5{grid-template-columns:minmax(0,7fr) minmax(0,5fr);}
.yw-grid--8-3{grid-template-columns:minmax(0,8fr) minmax(0,3fr);}
.yw-grid--12{grid-template-columns:repeat(12,minmax(0,1fr));}

/* ---------- 头部 ---------- */
.yw-header{
  position:sticky;
  top:0;
  z-index:60;
  background:var(--paper-100);
}

.yw-header__top{
  background:var(--ink-900);
  color:var(--paper-200);
  border-bottom:3px solid var(--orange-500);
}
.yw-header__top-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:clamp(12px,3vw,32px);
  min-height:60px;
  padding-block:.4rem;
}

.yw-brand{
  display:inline-flex;
  align-items:center;
  gap:.65rem;
  color:inherit;
  flex:none;
}
.yw-brand__mark{
  display:grid;
  place-items:center;
  width:38px;
  height:38px;
  flex:none;
  background:var(--orange-500);
  color:#fff;
  font-weight:900;
  font-size:1.12rem;
  border-radius:var(--r-sm);
  box-shadow:inset 0 -3px 0 rgba(0,0,0,.20);
}
.yw-brand__text{display:flex;flex-direction:column;line-height:1.24;}
.yw-brand__name{font-weight:900;font-size:1.06rem;letter-spacing:.04em;}
.yw-brand__sub{font-size:.76rem;letter-spacing:.14em;color:var(--sand-200);}

.yw-header__note{
  margin:0;
  font-family:var(--font-mono);
  font-size:.79rem;
  letter-spacing:.02em;
  color:rgba(232,217,168,.86);
  text-align:right;
}

.yw-header__bar{
  position:relative;
  background:linear-gradient(180deg, var(--paper-100), var(--paper-200));
  border-bottom:1px solid var(--line-300);
  box-shadow:var(--shadow-1);
  transition:box-shadow var(--dur) var(--ease);
}
.yw-header.is-stuck .yw-header__bar{box-shadow:0 12px 30px -22px rgba(14,26,43,.85);}
.yw-header__bar-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:.75rem;
  min-height:58px;
}

.yw-nav{flex:1 1 auto;min-width:0;}
.yw-nav__list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:.22rem;
  padding:0;
  list-style:none;
}
.yw-nav__link{
  display:block;
  position:relative;
  padding:.5rem .78rem;
  border:1px solid transparent;
  border-radius:var(--r-sm);
  color:var(--ink-900);
  font-weight:700;
  font-size:.97rem;
  letter-spacing:.03em;
  transition:background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.yw-nav__link::before{
  content:"";
  display:inline-block;
  width:6px;
  height:6px;
  margin-right:.46rem;
  background:var(--sand-500);
  transform:translateY(-2px) rotate(45deg);
  transition:background var(--dur) var(--ease);
}
.yw-nav__link:hover{background:var(--ink-900);color:var(--paper-100);}
.yw-nav__link:hover::before{background:var(--orange-300);}
.yw-nav__link[aria-current="page"]{
  background:var(--orange-500);
  border-color:var(--orange-500);
  color:#fff;
  box-shadow:inset 0 -3px 0 var(--sand-500);
}
.yw-nav__link[aria-current="page"]::before{background:var(--sand-200);}

.yw-nav-toggle{
  display:none;
  align-items:center;
  gap:.5rem;
  padding:.5rem .8rem;
  background:var(--ink-900);
  color:var(--paper-100);
  border:1px solid var(--ink-900);
  border-radius:var(--r-sm);
  font-weight:700;
  font-size:.9rem;
  letter-spacing:.06em;
  cursor:pointer;
}
.yw-nav-toggle__bars{display:inline-flex;flex-direction:column;gap:3px;width:16px;}
.yw-nav-toggle__bars span{
  display:block;
  height:2px;
  background:var(--orange-300);
  border-radius:2px;
  transition:transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}
.yw-nav-toggle[aria-expanded="true"] .yw-nav-toggle__bars span:nth-child(1){transform:translateY(5px) rotate(45deg);}
.yw-nav-toggle[aria-expanded="true"] .yw-nav-toggle__bars span:nth-child(2){opacity:0;}
.yw-nav-toggle[aria-expanded="true"] .yw-nav-toggle__bars span:nth-child(3){transform:translateY(-5px) rotate(-45deg);}

.yw-header__cta{flex:none;white-space:nowrap;}

.yw-progress{
  position:absolute;
  left:0;
  right:0;
  bottom:-3px;
  height:3px;
  background:rgba(199,188,168,.55);
  overflow:hidden;
}
.yw-progress__bar{
  display:block;
  width:100%;
  height:100%;
  background:linear-gradient(90deg, var(--orange-500), var(--sand-500));
  transform:scaleX(0);
  transform-origin:0 50%;
  transition:transform 120ms linear;
}

/* ---------- 按钮 ---------- */
.yw-btn{
  display:inline-flex;
  align-items:center;
  gap:.45rem;
  padding:.62rem 1.05rem;
  border:1px solid transparent;
  border-radius:var(--r-sm);
  font-size:.94rem;
  font-weight:700;
  letter-spacing:.03em;
  text-decoration:none;
  cursor:pointer;
  transition:background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.yw-btn--primary{
  background:var(--orange-500);
  color:#fff;
  box-shadow:0 2px 0 var(--sand-500);
}
.yw-btn--primary:hover{background:var(--ink-900);box-shadow:0 2px 0 var(--orange-500);}
.yw-btn--ghost{
  background:transparent;
  color:var(--ink-900);
  border-color:var(--ink-900);
}
.yw-btn--ghost:hover{background:var(--ink-900);color:var(--paper-100);}
.yw-btn--quiet{
  background:var(--sand-200);
  color:var(--ink-900);
  border-color:var(--sand-500);
}
.yw-btn--quiet:hover{background:var(--sand-500);color:#fff;}
.yw-btn--sm{padding:.4rem .72rem;font-size:.85rem;}

/* ---------- 面包屑 ---------- */
.yw-crumbs{margin:0 0 clamp(14px,2vw,22px);font-size:.85rem;}
.yw-crumbs ol{display:flex;flex-wrap:wrap;gap:.4rem;padding:0;list-style:none;}
.yw-crumbs li{display:flex;align-items:center;gap:.4rem;color:var(--ink-700);}
.yw-crumbs li + li::before{content:"/";color:var(--line-300);}
.yw-crumbs a{color:var(--ink-700);border-bottom:1px solid var(--line-300);}
.yw-crumbs a:hover{color:var(--orange-500);border-color:var(--orange-500);}

/* ---------- 正文与章节 ---------- */
.yw-lead{
  font-size:clamp(1.05rem,1.6vw,1.25rem);
  line-height:1.85;
  color:var(--ink-700);
  max-width:64ch;
}
.yw-prose{max-width:72ch;}
.yw-prose h2{font-size:clamp(1.4rem,2.4vw,1.75rem);margin:2.2rem 0 .8rem;}
.yw-prose h3{font-size:1.2rem;margin:1.6rem 0 .6rem;}
.yw-prose ul,.yw-prose ol{padding-left:1.3rem;margin-bottom:1rem;}
.yw-prose a{color:var(--orange-500);text-decoration:underline;text-underline-offset:3px;}
.yw-prose code{
  font-family:var(--font-mono);
  font-size:.9em;
  background:var(--sand-200);
  padding:.08rem .34rem;
  border-radius:var(--r-sm);
}
.yw-note{
  margin:1.2rem 0;
  padding:.9rem 1.1rem .9rem 1.4rem;
  background:rgba(232,217,168,.45);
  border-left:4px solid var(--sand-500);
  border-radius:0 var(--r-sm) var(--r-sm) 0;
  color:var(--ink-700);
  font-size:.95rem;
}

.yw-chapter{
  display:flex;
  align-items:flex-start;
  gap:clamp(12px,2vw,22px);
  margin-bottom:clamp(16px,2.4vw,28px);
}
.yw-chapter__num{
  flex:none;
  font-family:var(--font-mono);
  font-size:clamp(1.5rem,3.4vw,2.4rem);
  font-weight:700;
  line-height:1;
  color:#fff;
  background:var(--ink-900);
  padding:.34rem .6rem .42rem;
  border-left:5px solid var(--sand-500);
  letter-spacing:.02em;
}
.yw-chapter__title{font-size:clamp(1.5rem,3vw,2rem);}
.yw-chapter__desc{margin:.42rem 0 0;color:var(--ink-700);font-size:1rem;max-width:60ch;}
.yw-kicker{
  display:inline-block;
  font-family:var(--font-mono);
  font-size:.76rem;
  font-weight:700;
  letter-spacing:.2em;
  color:var(--orange-500);
  margin-bottom:.5rem;
}

/* ---------- 卡片 ---------- */
.yw-card{
  background:var(--paper-200);
  border:1px solid var(--line-300);
  border-radius:var(--r-md);
  padding:clamp(16px,2vw,24px);
  box-shadow:var(--shadow-1);
  transition:transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.yw-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-2);}
.yw-card--ink{
  background:var(--ink-900);
  color:var(--paper-100);
  border-color:var(--ink-700);
}
.yw-card--ink .yw-card__meta{color:var(--sand-200);}
.yw-card--accent{border-left:6px solid var(--orange-500);}
.yw-card__title{margin:0 0 .5rem;font-size:1.15rem;}
.yw-card__meta{
  display:block;
  font-family:var(--font-mono);
  font-size:.79rem;
  letter-spacing:.05em;
  color:var(--celadon-500);
  margin-bottom:.4rem;
}

/* ---------- 标签 / chips ---------- */
.yw-chips{display:flex;flex-wrap:wrap;gap:.45rem;padding:0;list-style:none;}
.yw-chip{
  display:inline-flex;
  align-items:center;
  gap:.35rem;
  padding:.3rem .72rem;
  background:rgba(255,255,255,.42);
  border:1px solid var(--line-300);
  border-radius:var(--r-full);
  color:var(--ink-700);
  font-size:.85rem;
  font-weight:600;
  cursor:pointer;
  transition:background var(--dur) var(--ease), color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.yw-chip:hover{background:var(--sand-200);border-color:var(--sand-500);color:var(--ink-900);}
.yw-chip[aria-pressed="true"],
.yw-chip.is-active{background:var(--orange-500);border-color:var(--orange-500);color:#fff;}
.yw-chip--celadon[aria-pressed="true"],
.yw-chip--celadon.is-active{background:var(--celadon-500);border-color:var(--celadon-500);}

/* ---------- 表格 ---------- */
.yw-table__wrap{
  overflow-x:auto;
  border:1px solid var(--line-300);
  border-radius:var(--r-md);
  background:rgba(255,255,255,.36);
}
.yw-table{width:100%;min-width:520px;font-size:.95rem;}
.yw-table caption{
  text-align:left;
  padding:.7rem .8rem 0;
  font-weight:900;
  color:var(--ink-900);
}
.yw-table th,
.yw-table td{
  padding:.62rem .72rem;
  text-align:left;
  vertical-align:top;
  border-bottom:1px solid var(--line-300);
}
.yw-table thead th{
  background:var(--sand-200);
  border-bottom:2px solid var(--sand-500);
  font-size:.85rem;
  font-weight:900;
  letter-spacing:.05em;
}
.yw-table tbody tr:hover{background:rgba(243,161,95,.20);}
.yw-table .is-num{
  font-family:var(--font-mono);
  font-size:.88rem;
  letter-spacing:.02em;
  white-space:nowrap;
}

/* ---------- 地图底板 ---------- */
.yw-map{
  position:relative;
  min-height:clamp(220px,38vw,420px);
  background-color:var(--paper-200);
  background-image:
    linear-gradient(rgba(199,188,168,.55) 1px, transparent 1px),
    linear-gradient(90deg, rgba(199,188,168,.55) 1px, transparent 1px),
    radial-gradient(420px 260px at 78% 18%, rgba(79,125,105,.18), transparent 70%);
  background-size:38px 38px, 38px 38px, 100% 100%;
  border:1px solid var(--line-300);
  border-radius:var(--r-md);
  overflow:hidden;
}
.yw-map__pin{
  position:absolute;
  display:block;
  width:14px;
  height:14px;
  background:var(--orange-500);
  border:2px solid #fff;
  border-radius:var(--r-full);
  box-shadow:0 4px 10px -4px rgba(14,26,43,.7);
}
.yw-map__label{
  position:absolute;
  padding:.16rem .45rem;
  background:var(--paper-100);
  border:1px solid var(--line-300);
  border-radius:var(--r-sm);
  font-family:var(--font-mono);
  font-size:.74rem;
  letter-spacing:.02em;
  color:var(--ink-900);
  white-space:nowrap;
}
.yw-map__legend{
  position:absolute;
  left:.9rem;
  bottom:.9rem;
  display:flex;
  flex-wrap:wrap;
  gap:.7rem;
  padding:.5rem .7rem;
  background:rgba(245,239,227,.92);
  border:1px solid var(--line-300);
  border-radius:var(--r-sm);
  font-size:.78rem;
  color:var(--ink-700);
}

/* ---------- 图片容器 ---------- */
.yw-figure{margin:0;display:flex;flex-direction:column;gap:.6rem;}
.yw-figure__frame{
  position:relative;
  overflow:hidden;
  border:1px solid var(--line-300);
  border-radius:var(--r-md);
  background:linear-gradient(135deg, var(--paper-200), var(--sand-200));
  box-shadow:var(--shadow-1);
}
.yw-figure__frame img{
  display:block;
  width:100%;
  height:100%;
  object-fit:cover;
  aspect-ratio:var(--ratio, 4 / 3);
}
.yw-figure--wide .yw-figure__frame img{aspect-ratio:16 / 9;}
.yw-figure--tall .yw-figure__frame img{aspect-ratio:3 / 4;}
.yw-figure__cap{
  font-family:var(--font-mono);
  font-size:.8rem;
  letter-spacing:.02em;
  color:var(--ink-700);
}

/* ---------- 步骤（技能树式路径） ---------- */
.yw-steps{display:grid;gap:1rem;padding:0;list-style:none;}
.yw-step{position:relative;padding-left:3rem;}
.yw-step__num{
  position:absolute;
  left:0;
  top:.1rem;
  display:grid;
  place-items:center;
  width:2.1rem;
  height:2.1rem;
  background:var(--ink-900);
  color:var(--sand-200);
  font-family:var(--font-mono);
  font-size:.86rem;
  font-weight:700;
  border-radius:var(--r-full);
}
.yw-step__title{display:block;font-size:1.05rem;font-weight:900;margin-bottom:.2rem;}

/* ---------- 状态标识 ---------- */
.yw-badge{
  display:inline-block;
  padding:.1rem .5rem;
  background:var(--celadon-500);
  color:#fff;
  border-radius:var(--r-sm);
  font-size:.74rem;
  font-weight:700;
  letter-spacing:.07em;
}
.yw-badge--alert{background:var(--alert-500);}
.yw-badge--sand{background:var(--sand-200);color:var(--ink-900);}

/* ---------- 粘性目录 ---------- */
.yw-toc{
  position:sticky;
  top:var(--sticky-offset);
  padding:1rem 1.1rem;
  background:var(--paper-200);
  border:1px solid var(--line-300);
  border-radius:var(--r-md);
}
.yw-toc__title{
  margin:0 0 .6rem;
  font-size:.8rem;
  font-weight:900;
  letter-spacing:.16em;
  color:var(--celadon-500);
}
.yw-toc__list{display:flex;flex-direction:column;gap:.28rem;padding:0;list-style:none;}
.yw-toc__link{
  display:block;
  padding:.32rem .55rem;
  border-left:3px solid transparent;
  color:var(--ink-700);
  font-size:.92rem;
  transition:background var(--dur) var(--ease), border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
.yw-toc__link:hover{background:rgba(196,154,43,.18);color:var(--ink-900);}
.yw-toc__link[aria-current]{
  border-left-color:var(--orange-500);
  background:rgba(243,161,95,.20);
  color:var(--ink-900);
  font-weight:700;
}

/* ---------- 显现 ---------- */
[data-reveal]{
  opacity:0;
  transform:translateY(14px);
  transition:opacity 320ms var(--ease), transform 320ms var(--ease);
}
[data-reveal].is-visible{opacity:1;transform:none;}

/* ---------- 页脚 ---------- */
.yw-footer{
  margin-top:clamp(48px,8vw,96px);
  background:var(--ink-900);
  color:var(--paper-200);
  border-top:6px solid var(--orange-500);
}
.yw-footer__grid{
  display:grid;
  grid-template-columns:1.4fr 1fr 1fr 1.2fr;
  gap:clamp(20px,3vw,44px);
  padding:clamp(32px,5vw,62px) 0 clamp(24px,3vw,38px);
}
.yw-footer .yw-brand{color:var(--paper-100);}
.yw-footer .yw-brand__name{font-size:1.1rem;}
.yw-footer .yw-brand__sub{color:var(--sand-200);}
.yw-footer__tag{
  margin:.9rem 0 0;
  max-width:30ch;
  font-size:.92rem;
  line-height:1.75;
  color:rgba(245,239,227,.74);
}
.yw-footer__meta{
  margin:.7rem 0 0;
  font-family:var(--font-mono);
  font-size:.76rem;
  letter-spacing:.03em;
  color:var(--sand-200);
}
.yw-footer__title{
  margin:0 0 .85rem;
  padding-bottom:.5rem;
  border-bottom:1px solid rgba(232,217,168,.28);
  font-size:.84rem;
  font-weight:900;
  letter-spacing:.16em;
  color:var(--sand-200);
}
.yw-footer__list{display:flex;flex-direction:column;gap:.45rem;padding:0;list-style:none;}
.yw-footer__list a{
  color:var(--paper-100);
  font-size:.94rem;
  border-bottom:1px solid transparent;
  transition:color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.yw-footer__list a:hover{color:var(--orange-300);border-color:var(--orange-300);}
.yw-footer__list--contact{gap:.8rem;}
.yw-footer__label{
  display:block;
  font-size:.74rem;
  letter-spacing:.14em;
  color:rgba(232,217,168,.72);
}
.yw-footer__value{
  display:block;
  font-family:var(--font-mono);
  font-size:.88rem;
  letter-spacing:.01em;
  color:var(--paper-100);
  word-break:break-word;
}
.yw-footer__base{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:.6rem 1.4rem;
  padding:1rem 0 1.7rem;
  border-top:1px solid rgba(232,217,168,.22);
  font-size:.81rem;
  color:rgba(245,239,227,.7);
}
.yw-footer__base p{margin:0;}
.yw-footer__icp{font-family:var(--font-mono);letter-spacing:.04em;}
.yw-footer__copy{font-family:var(--font-mono);letter-spacing:.02em;}
.yw-footer__note{color:rgba(232,217,168,.78);}

/* ---------- 平板 ---------- */
@media (max-width:1080px){
  :root{--sticky-offset:120px;}
  .yw-footer__grid{grid-template-columns:1.3fr 1fr 1fr;row-gap:2rem;}
  .yw-footer__col:last-child{grid-column:1 / -1;}
}

/* ---------- 移动 ---------- */
@media (max-width:900px){
  .yw-header__note{display:none;}
  .yw-nav-toggle{display:inline-flex;}

  .yw-nav{
    position:absolute;
    left:0;
    right:0;
    top:100%;
    z-index:70;
    display:none;
    padding:.6rem var(--gutter) 1.1rem;
    background:var(--paper-200);
    border-bottom:3px solid var(--orange-500);
    box-shadow:var(--shadow-2);
  }
  .yw-nav[data-open="true"]{display:block;}
  .yw-nav__list{flex-direction:column;align-items:stretch;gap:.1rem;}
  .yw-nav__link{
    padding:.72rem .8rem;
    border-radius:0;
    border-bottom:1px solid var(--line-300);
  }
  .yw-nav__link[aria-current="page"]{border-radius:var(--r-sm);border-bottom-color:var(--orange-500);}
  .yw-header__cta{padding:.5rem .8rem;font-size:.88rem;}

  .yw-grid--8-3,
  .yw-grid--7-5,
  .yw-grid--6-6,
  .yw-grid--3,
  .yw-grid--2{grid-template-columns:minmax(0,1fr);}
  .yw-toc{position:static;}
  .yw-footer__grid{grid-template-columns:1fr;gap:1.8rem;}
  .yw-footer__col:last-child{grid-column:auto;}
  .yw-footer__base{flex-direction:column;align-items:flex-start;}
}

@media (max-width:560px){
  body{font-size:1rem;}
  .yw-brand__sub{display:none;}
  .yw-chapter{flex-direction:column;gap:.6rem;}
  .yw-chapter__num{font-size:1.4rem;}
  .yw-footer__tag{max-width:none;}
}

/* ---------- 动效减弱 ---------- */
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto;}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  [data-reveal]{opacity:1;transform:none;}
  .yw-card:hover{transform:none;}
  .yw-skip{transition:none;}
  .yw-progress__bar{transition:none;}
}