@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:ital,wght@0,400;0,600;0,700;0,800;1,400&display=swap');

:root{
  --ink:#171f26;
  --ink-2:#4c5c6b;
  --blue:#c8e0f4;
  --pink:#f5e0e8;
  --bg:#e9eff5;
  --paper:#f1f6fa;
  --raise:-5px -5px 15px rgba(255,255,255,.85), 5px 5px 16px rgba(23,31,38,.10);
  --raise-sm:-3px -3px 8px rgba(255,255,255,.9), 3px 3px 9px rgba(23,31,38,.09);
  --sink:inset -4px -4px 10px rgba(255,255,255,.85), inset 4px 4px 10px rgba(23,31,38,.11);
  --r-lg:16px;
  --r-sm:4px;
  --edge:rgba(23,31,38,.09);
}

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

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

body{
  margin:0;
  background:var(--bg);
  color:var(--ink);
  font-family:'Plus Jakarta Sans', system-ui, -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  font-size:1.0625rem;
  line-height:1.8;
  overflow-x:hidden;
}

img{ max-width:100%; }

a{ color:inherit; }

h1,h2,h3{ line-height:1.3; letter-spacing:-.01em; }

/* 顶栏 */
.top{
  position:sticky;
  top:0;
  z-index:40;
  padding:10px clamp(14px,4vw,44px) 10px;
  background:linear-gradient(180deg,#f4f9fd,#e6eef6);
  border-radius:0 0 var(--r-lg) var(--r-lg);
  box-shadow:0 8px 20px rgba(23,31,38,.08);
}

.brand-row{
  display:flex;
  align-items:center;
  justify-content:space-between;
  max-width:1180px;
  margin:0 auto;
}

.logo{
  display:inline-flex;
  align-items:center;
  gap:10px;
  min-height:44px;
  padding:4px 12px 4px 4px;
  border-radius:12px;
  text-decoration:none;
  font-weight:800;
  font-size:1.05rem;
  letter-spacing:-.01em;
  box-shadow:var(--raise-sm);
  background:linear-gradient(145deg,#f6fbff,#dde8f2);
  transition:box-shadow .15s ease, transform .15s ease;
}

.logo:active{ box-shadow:var(--sink); transform:scale(.98); }

.logo-mark{
  display:block;
  width:34px;
  height:34px;
  border-radius:9px;
  object-fit:cover;
}

.logo-text{ padding-right:6px; white-space:nowrap; }

.menu-row{
  display:flex;
  flex-wrap:wrap;
  gap:6px;
  max-width:1180px;
  margin:8px auto 0;
}

.menu-link{
  display:inline-flex;
  align-items:center;
  min-height:40px;
  padding:8px 13px;
  border-radius:12px;
  color:var(--ink-2);
  text-decoration:none;
  font-size:.95rem;
  font-weight:600;
  background:linear-gradient(145deg,#f2f8fd,#e2ebf4);
  box-shadow:var(--raise-sm);
  transition:transform .15s ease, color .15s ease, box-shadow .15s ease;
}

.menu-link:hover{ color:var(--ink); transform:translateY(-1px); }
.menu-link:active{ transform:scale(.96); box-shadow:var(--sink); }

/* 头图 */
.hero{
  position:relative;
  display:flex;
  align-items:flex-end;
  justify-content:flex-end;
  min-height:70vh;
  padding:clamp(26px,6vw,64px) clamp(16px,5vw,64px) clamp(44px,8vw,96px);
  text-align:right;
  background:linear-gradient(150deg,var(--blue),var(--pink) 78%);
  border-radius:0 0 clamp(56px,10vw,110px) clamp(56px,10vw,110px);
  overflow:hidden;
  box-shadow:0 18px 34px rgba(23,31,38,.10);
}

.hero-bg{ position:absolute; inset:0; }

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

.hero-bg::after{
  content:"";
  position:absolute;
  inset:0;
  background:linear-gradient(to top, rgba(233,239,245,.95), rgba(233,239,245,.18) 65%);
}

.hero-copy{
  position:relative;
  z-index:2;
  max-width:34ch;
}

.hero h1{
  margin:0 0 12px;
  font-size:clamp(1.9rem,5.2vw,3.4rem);
  font-weight:800;
  letter-spacing:-.03em;
  text-shadow:0 1px 0 rgba(255,255,255,.6);
}

.hero-desc{
  margin:0 0 0 auto;
  max-width:30ch;
  color:var(--ink-2);
  font-size:1rem;
  line-height:1.7;
}

/* 版心 */
.wrap{
  display:grid;
  grid-template-columns:252px minmax(0,1fr);
  gap:clamp(18px,3vw,38px);
  align-items:start;
  max-width:1180px;
  margin:0 auto;
  padding:clamp(26px,5vw,54px) clamp(14px,4vw,40px) 20px;
}

.side{ position:sticky; top:150px; }

.side-box{
  padding:16px 14px 18px;
  border-radius:var(--r-lg);
  background:linear-gradient(145deg,#f2f8fd,#e2ebf4);
  box-shadow:var(--raise);
}

.side-eyebrow{
  display:block;
  font-size:.72rem;
  font-weight:700;
  letter-spacing:.34em;
  text-transform:uppercase;
  color:var(--ink-2);
}

.side-title{
  margin:2px 0 10px;
  font-size:1.15rem;
  font-weight:800;
}

.toc{
  margin:0;
  padding:0;
  list-style:none;
}

.toc a{
  display:flex;
  align-items:center;
  min-height:40px;
  padding:6px 10px;
  border-radius:10px;
  text-decoration:none;
  color:var(--ink-2);
  font-size:.95rem;
  font-weight:600;
  transition:background .15s ease, color .15s ease;
}

.toc a:hover{ background:rgba(255,255,255,.75); color:var(--ink); }
.toc a:active{ box-shadow:var(--sink); }

/* 正文 */
.content-sec{ min-width:0; }

.content{
  padding:clamp(18px,3.2vw,38px);
  border-radius:var(--r-lg);
  background:var(--paper);
  box-shadow:var(--raise);
}

.content > article{ scroll-margin-top:148px; }

.content > article + article{
  margin-top:38px;
  padding-top:30px;
  border-top:1px dashed var(--edge);
}

.content h2{
  margin:0 0 14px;
  font-size:clamp(1.28rem,2.6vw,1.72rem);
  font-weight:800;
}

.content h3{
  margin:26px 0 10px;
  font-size:1.12rem;
  font-weight:700;
}

.content p{
  margin:0 0 16px;
  color:#22303a;
}

.content ul,.content ol{
  margin:0 0 18px;
  padding-left:1.35em;
}

.content li{ margin-bottom:8px; }

.content a{
  color:#1d5e8c;
  text-underline-offset:3px;
}

.content img{
  display:block;
  margin:18px 0;
  border-radius:var(--r-sm);
  box-shadow:0 10px 22px rgba(23,31,38,.12);
  height:auto;
}

.content blockquote{
  margin:20px 0;
  padding:14px 18px;
  border-radius:var(--r-lg);
  background:linear-gradient(145deg,#f6ecf1,#f0e2ea);
  box-shadow:var(--sink);
  color:#3a2c34;
}

.content blockquote p:last-child{ margin-bottom:0; }

.content figure{ margin:18px 0; }
.content figcaption{ font-size:.9rem; color:var(--ink-2); }

/* 页脚 */
footer{
  display:grid;
  grid-template-columns:minmax(0,1fr) auto;
  gap:10px 28px;
  align-items:center;
  margin-top:44px;
  padding:22px clamp(14px,4vw,44px) 26px;
  border-radius:clamp(40px,8vw,90px) clamp(40px,8vw,90px) 0 0;
  background:linear-gradient(180deg,#e6eef6,#dbe6f1);
  box-shadow:inset 0 10px 22px rgba(255,255,255,.7);
}

footer dl{
  display:flex;
  flex-wrap:wrap;
  gap:2px 6px;
  margin:0;
}

footer dt,footer dd{ margin:0; }

footer dl a{
  display:inline-flex;
  align-items:center;
  min-height:40px;
  padding:8px 11px;
  border-radius:10px;
  text-decoration:none;
  color:var(--ink-2);
  font-size:.92rem;
  font-weight:600;
  transition:color .15s ease, background .15s ease;
}

footer dl a:hover{ color:var(--ink); background:rgba(255,255,255,.65); }

.foot-end{ text-align:right; }

.foot-copy{
  margin:0;
  font-size:.9rem;
  color:var(--ink-2);
}

/* 入场动效 */
html.js .content > article,
html.js .side-box,
html.js .foot-links,
html.js .foot-end{
  opacity:0;
  transform:translateY(12px);
  transition:opacity .5s ease, transform .5s ease;
}

html.js .is-in{
  opacity:1;
  transform:none;
}

/* 窄屏 */
@media (max-width:900px){
  .wrap{ grid-template-columns:minmax(0,1fr); }
  .side{ position:static; }
  .toc{ display:flex; flex-wrap:wrap; gap:4px; }
  .toc li{ flex:1 1 auto; }
  .toc a{ padding:6px 8px; font-size:.9rem; }
  footer{ grid-template-columns:minmax(0,1fr); }
  .foot-end{ text-align:left; }
}

@media (max-width:600px){
  .hero{
    min-height:56vh;
    padding:24px 18px 56px;
    border-radius:0 0 48px 48px;
  }
  .hero h1{ font-size:clamp(1.7rem,8vw,2.3rem); }
  .hero-desc{ font-size:.95rem; }
  .content > article{ scroll-margin-top:172px; }
  .menu-link{ padding:8px 10px; font-size:.9rem; }
}

@media (prefers-reduced-motion:reduce){
  html{ scroll-behavior:auto; }
  html.js .content > article,
  html.js .side-box,
  html.js .foot-links,
  html.js .foot-end{
    opacity:1;
    transform:none;
    transition:none;
  }
  .menu-link,.logo,.toc a{ transition:none; }
}

button[aria-expanded]{min-width:44px;min-height:44px}