@import url('https://fonts.googleapis.com/css2?family=Nunito+Sans:wght@300;400;500;600;700&family=Varela+Round&display=swap');

:root{
  --ice:#c8e0f4;
  --rose:#f5e0e8;
  --ink:#171f26;
  --bg1:#eef4fb;
  --bg2:#f8eef3;
  --soft:-5px -5px 15px rgba(255,255,255,.82),5px 5px 15px rgba(23,31,38,.13);
  --softin:inset -4px -4px 10px rgba(255,255,255,.78),inset 4px 4px 10px rgba(23,31,38,.13);
  --face:'Varela Round','Nunito Sans',system-ui,-apple-system,'PingFang SC','Microsoft YaHei',sans-serif;
}

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{
  margin:0;
  font-family:'Nunito Sans',system-ui,-apple-system,'PingFang SC','Microsoft YaHei',sans-serif;
  font-size:16.5px;
  line-height:1.78;
  color:var(--ink);
  overflow-wrap:break-word;
  overflow-x:hidden;
  background:linear-gradient(150deg,var(--bg1),var(--bg2) 58%,#e6eef8);
  background-attachment:fixed;
}
body.menu-open{overflow:hidden}
a{color:var(--ink)}
img{max-width:100%;height:auto}
h1,h2,h3{font-family:var(--face);font-weight:600}
a:focus-visible,button:focus-visible,input:focus-visible{outline:3px solid #1d5f8a;outline-offset:2px}

.skip{position:fixed;left:10px;top:-70px;z-index:70;padding:12px 18px;border-radius:14px;background:#fff;color:var(--ink);text-decoration:none;box-shadow:var(--soft)}
.skip:focus{top:10px}

/* 顶栏 / 侧栏 */
.sitehead{
  position:sticky;top:0;z-index:40;
  display:flex;flex-direction:column;gap:10px;
  padding:12px 16px;
  background:rgba(238,244,251,.94);
  backdrop-filter:blur(8px);
  box-shadow:0 6px 18px rgba(23,31,38,.1);
}
.brandrow{display:flex;align-items:center;justify-content:space-between;gap:12px}
.brand{display:flex;align-items:center;gap:10px;min-height:44px;text-decoration:none;font-family:var(--face);font-size:1.04rem}
.brand .mark{width:34px;height:34px;border-radius:12px;background:#fff;object-fit:cover;box-shadow:var(--soft)}
.brandtext{font-weight:600;letter-spacing:.02em}

.burger{
  flex:0 0 auto;width:48px;height:48px;border:0;border-radius:14px;
  display:flex;flex-direction:column;align-items:center;justify-content:center;gap:5px;
  background:linear-gradient(145deg,#f4f9fe,#dbe8f4);
  box-shadow:var(--soft);cursor:pointer;
  transition:transform .15s ease,box-shadow .15s ease;
}
.burger span{display:block;width:20px;height:2.5px;border-radius:3px;background:var(--ink);transition:transform .2s ease,opacity .2s ease}
.burger:active{box-shadow:var(--softin);transform:scale(.96)}
body.menu-open .burger span:nth-child(1){transform:translateY(7.5px) rotate(45deg)}
body.menu-open .burger span:nth-child(2){opacity:0}
body.menu-open .burger span:nth-child(3){transform:translateY(-7.5px) rotate(-45deg)}

.sbox,.sform{display:flex;gap:8px}
.sinput,.finput{
  flex:1 1 auto;min-width:0;min-height:44px;padding:10px 16px;
  border:0;border-radius:14px;background:#e9f1fa;box-shadow:var(--softin);
  font:inherit;font-size:16px;color:var(--ink);
}
.sinput::placeholder,.finput::placeholder{color:#5c6b78}
.sbtn,.fbtn{
  flex:0 0 auto;min-height:44px;padding:10px 16px;border:0;border-radius:14px;
  background:linear-gradient(145deg,#f9eef3,#e8d8e1);box-shadow:var(--soft);
  font:inherit;font-size:16px;color:var(--ink);cursor:pointer;
  transition:transform .15s ease,box-shadow .15s ease;
}
.sbtn:active,.fbtn:active{box-shadow:var(--softin);transform:scale(.97)}

/* 全屏菜单 */
.menu{
  position:fixed;inset:0;z-index:35;
  display:flex;align-items:flex-start;justify-content:center;
  padding:136px 20px 32px;overflow-y:auto;
  background:linear-gradient(160deg,#e5effa,#f9edf2);
  opacity:0;visibility:hidden;transform:translateY(-10px);
  transition:opacity .22s ease,transform .22s ease,visibility .22s;
}
body.menu-open .menu{opacity:1;visibility:visible;transform:none}
.menurow{display:flex;flex-wrap:wrap;gap:10px 12px;justify-content:center;margin:0;max-width:560px}
.menurow a{
  display:inline-flex;align-items:center;min-height:48px;padding:11px 20px;
  border-radius:16px;background:linear-gradient(145deg,#f3f8fe,#dfe9f4);
  box-shadow:var(--soft);text-decoration:none;font-size:1rem;
  transition:transform .15s ease,box-shadow .15s ease;
}
.menurow a:hover{background:linear-gradient(145deg,#fcf1f5,#eddfe8)}
.menurow a:active{box-shadow:var(--softin);transform:scale(.97)}

/* 正文骨架 */
.stage{max-width:1160px;margin:0 auto;padding:22px 16px 48px}
main{display:grid;grid-template-columns:minmax(0,1fr);gap:28px}
div{min-width:0}

.hero{
  position:relative;min-height:70vh;
  display:flex;flex-direction:column;justify-content:center;align-items:flex-end;
  text-align:right;gap:14px;padding:28px 2px 64px;
}
.hero::after{
  content:"";position:absolute;left:0;right:0;bottom:0;height:58px;
  background:linear-gradient(90deg,var(--ice),var(--rose));
  clip-path:polygon(0 64%,100% 0,100% 100%,0 100%);
}
.hero h1{
  margin:0;max-width:16ch;
  font-size:clamp(2.05rem,9.5vw,4.5rem);line-height:1.16;letter-spacing:.01em;
}
.herop{margin:0;max-width:34ch;font-size:1rem;color:#3b4a57}

.content{min-width:0}
.content > section{
  background:rgba(255,255,255,.66);
  padding:26px 20px;margin:0 0 18px;
  scroll-margin-top:132px;
}
.content > section:nth-child(even){background:rgba(245,224,232,.68)}
.content > section:nth-child(3n){background:rgba(200,224,244,.48)}
.content h2{font-size:1.3rem;line-height:1.42;margin:0 0 12px;letter-spacing:.01em}
.content h2 > span{display:inline-block;padding-bottom:6px;box-shadow:inset 0 -8px 0 rgba(245,224,232,.95)}
.content h3{font-size:1.08rem;line-height:1.5;margin:22px 0 8px}
.content h3 > span{display:inline-block;padding-bottom:4px;box-shadow:inset 0 -6px 0 rgba(200,224,244,.95)}
.content p{margin:0 0 12px}
.content ul,.content ol{margin:0 0 14px;padding-left:1.3em}
.content li{margin:0 0 8px}
.content a{color:#1d5f8a;text-decoration:underline;text-underline-offset:3px;overflow-wrap:anywhere}
.content strong{font-weight:700}
.content blockquote{
  margin:0 0 14px;padding:14px 16px;
  background:rgba(255,255,255,.74);box-shadow:var(--soft);
}
.content table{display:block;width:100%;overflow-x:auto;border-collapse:collapse;font-size:.95rem;margin:0 0 14px}
.content th,.content td{padding:8px 10px;text-align:left;box-shadow:inset 0 -1px 0 rgba(23,31,38,.12)}
.content pre{overflow-x:auto;padding:14px 16px;background:rgba(255,255,255,.8);box-shadow:var(--soft);font-size:.92rem}
.content img{display:block;margin:0 0 14px}
.flash{box-shadow:0 0 0 4px rgba(29,95,138,.32)}

/* 侧栏 */
.side{display:flex;flex-direction:column;gap:14px;align-self:start;min-width:0}
.sideh{margin:0;font-size:1rem}
.sideh span{
  display:inline-block;padding:7px 16px;border-radius:14px;
  background:linear-gradient(145deg,#eff6fd,#dfeaf5);box-shadow:var(--soft);
}
.sidels{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:8px}
.sidels a{
  display:flex;align-items:center;min-height:44px;padding:10px 14px;
  border-radius:16px;text-decoration:none;font-size:.97rem;
  background:linear-gradient(145deg,#f4f9fe,#e2ecf6);box-shadow:var(--soft);
  transition:transform .15s ease,box-shadow .15s ease;
}
.sidels a:active{box-shadow:var(--softin);transform:scale(.98)}
.totop{
  align-self:flex-start;min-height:44px;padding:10px 18px;border:0;border-radius:16px;
  background:linear-gradient(145deg,#fbefe4,#eedbe4);
  box-shadow:var(--soft);font:inherit;font-size:.95rem;color:var(--ink);cursor:pointer;
  transition:transform .15s ease,box-shadow .15s ease;
}
.totop:active{box-shadow:var(--softin);transform:scale(.97)}

/* 页脚 */
.sitefoot{padding:32px 16px 26px;background:linear-gradient(160deg,#e4eef9,#f7ebf1);box-shadow:0 -8px 20px rgba(23,31,38,.08)}
.fgrid{display:grid;grid-template-columns:minmax(0,1fr);gap:26px;max-width:1160px;margin:0 auto}
.fcolh{margin:0 0 10px;font-size:1rem}
.fcolh span{display:inline-block;padding-bottom:4px;box-shadow:inset 0 -8px 0 rgba(200,224,244,.95)}
.fbrand{margin:0 0 12px;font-family:var(--face);font-size:1.04rem}
.fdl{margin:0;min-width:0}
.fdl dt{font-size:.9rem;letter-spacing:.06em;color:#3d4c59;margin-bottom:8px}
.fdl dd{margin:0}
.fdl a{display:inline-flex;align-items:center;min-height:40px;padding:5px 0;text-decoration:none}
.fdl a:hover{text-decoration:underline}
.fdl dd:not(:has(a)){min-height:32px;padding:5px 0;font-size:.95rem;color:#3d4c59;overflow-wrap:anywhere}
.fbottom{
  display:flex;flex-wrap:wrap;gap:10px 20px;justify-content:space-between;align-items:center;
  max-width:1160px;margin:26px auto 0;padding-top:16px;
  box-shadow:inset 0 1px 0 rgba(23,31,38,.1);
}
.copy{margin:0;font-size:.9rem;color:#3d4c59}
.flinks{display:flex;gap:18px;margin:0}
.flinks a{display:inline-flex;align-items:center;min-height:40px;text-decoration:none}

/* 入场 */
.rv{opacity:0;transform:translateY(14px);transition:opacity .5s ease,transform .5s ease}
.rv.in{opacity:1;transform:none}

@media (min-width:600px){
  .sitehead{padding:14px 24px}
  .stage{padding:26px 24px 56px}
  .content > section{padding:30px 26px;margin-bottom:22px}
  .fgrid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .sitefoot{padding:38px 24px 26px}
}

@media (min-width:960px){
  body{padding-left:264px}
  .sitehead{
    position:fixed;inset:0 auto 0 0;width:264px;height:100vh;overflow-y:auto;
    justify-content:flex-start;gap:20px;padding:24px 18px;
    background:linear-gradient(165deg,#eaf2fb,#f8edf2);
    backdrop-filter:none;box-shadow:8px 0 24px rgba(23,31,38,.09);
  }
  .brandrow{flex-direction:column;align-items:flex-start;gap:16px}
  .brand{width:100%}
  .burger{width:100%;height:48px;flex-direction:row;gap:6px}
  .burger span{transition:transform .2s ease,opacity .2s ease}
  body.menu-open .burger span:nth-child(1){transform:rotate(45deg) translateX(0)}
  body.menu-open .burger span:nth-child(2){opacity:0}
  body.menu-open .burger span:nth-child(3){transform:rotate(-45deg)}
  .sbox{flex-direction:column}
  .menu{inset:0;padding:56px 40px;align-items:center;justify-content:center}
  .menurow{max-width:640px}
  .stage{padding:34px 32px 64px}
  main{grid-template-columns:minmax(0,1fr) 262px;gap:36px}
  .side{position:sticky;top:28px}
  .hero{padding:36px 0 72px}
  .content > section{scroll-margin-top:28px;padding:34px 32px}
  .sitefoot{padding:42px 32px 28px}
  .fgrid{grid-template-columns:1.4fr 1fr 1fr 1fr;gap:32px}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .rv{opacity:1;transform:none;transition:none}
  *{transition-duration:.01ms !important;animation-duration:.01ms !important}
}

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