@import url('https://fonts.googleapis.com/css2?family=Chakra+Petch:wght@300;400;500;600;700&family=Russo+One&display=swap');

:root{
  --mint:#b4fde1;
  --blue:#add8e6;
  --ink:#172620;
  --mint-s:#e8fff7;
  --blue-s:#eaf6fb;
  --paper:#fbfffd;
  --r:20px;
  --bd:3px solid var(--ink);
  --sh:inset -2px -2px 8px rgba(23,38,32,.13), 4px 4px 8px rgba(23,38,32,.16);
  --sh-lift:inset -3px -3px 12px rgba(23,38,32,.11), 8px 10px 20px rgba(23,38,32,.2);
  --ease:cubic-bezier(.34,1.56,.64,1);
  --head:'Russo One','Chakra Petch',system-ui,-apple-system,'PingFang SC','Hiragino Sans GB','Microsoft YaHei',sans-serif;
  --body:'Chakra Petch',system-ui,-apple-system,'PingFang SC','Hiragino Sans GB','Microsoft YaHei',sans-serif;
}

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

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

body{
  margin:0;
  font-family:var(--body);
  font-size:17px;
  line-height:1.72;
  color:var(--ink);
  background:
    radial-gradient(720px 420px at 84% -8%, var(--mint) 0%, rgba(180,253,225,0) 62%),
    radial-gradient(620px 440px at 4% 14%, var(--blue) 0%, rgba(173,216,230,0) 58%),
    var(--paper);
  background-attachment:fixed;
  overflow-x:hidden;
}

h1,h2,h3,h4{
  font-family:var(--head);
  font-weight:400;
  line-height:1.16;
  letter-spacing:.01em;
  margin:0;
}

p{margin:0 0 14px}
a{color:var(--ink)}

:focus-visible{outline:3px solid #2c7f66;outline-offset:3px;border-radius:10px}

.skip{
  position:absolute;
  left:10px;
  top:-70px;
  z-index:80;
  display:inline-flex;
  align-items:center;
  min-height:44px;
  padding:10px 18px;
  border-radius:14px;
  background:var(--ink);
  color:#eafff7;
  text-decoration:none;
  font-weight:600;
  transition:top .22s ease-out;
}
.skip:focus{top:10px}

/* 顶部两行：品牌独占一行，菜单行在下 */
.top{
  position:sticky;
  top:0;
  z-index:40;
  background:linear-gradient(180deg,#ffffff 0%,var(--mint-s) 72%,#dffbf0 100%);
  border-bottom:3px solid var(--ink);
  box-shadow:0 6px 14px rgba(23,38,32,.14);
}

.brandrow{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  padding:12px 14px 8px;
}

.brand{
  display:inline-flex;
  align-items:center;
  gap:10px;
  min-height:44px;
  padding:4px 8px 4px 4px;
  border-radius:16px;
  text-decoration:none;
  transition:transform .2s var(--ease);
}
.brand:active{transform:scale(.97)}

.brand .logo{
  width:46px;
  height:46px;
  border-radius:14px;
  border:3px solid var(--ink);
  box-shadow:var(--sh);
  object-fit:cover;
  display:block;
}

.brand-t{
  font-family:var(--head);
  font-size:clamp(18px,4.6vw,25px);
  letter-spacing:.015em;
  line-height:1.1;
}

.contact{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-height:44px;
  padding:10px 16px;
  border:var(--bd);
  border-radius:999px;
  background:var(--blue);
  box-shadow:var(--sh);
  font-size:16px;
  font-weight:600;
  text-decoration:none;
  white-space:nowrap;
  transition:transform .2s var(--ease),box-shadow .2s ease-out;
}
.contact:active{
  transform:translateY(2px) scale(.98);
  box-shadow:inset 2px 3px 8px rgba(23,38,32,.26);
}

.menu{padding:0 12px 12px}

.menu p,
.foot-nav p{
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  margin:0;
}

.menu a{
  display:inline-flex;
  align-items:center;
  min-height:44px;
  padding:9px 13px;
  border:2.5px solid var(--ink);
  border-radius:14px;
  background:var(--mint);
  box-shadow:var(--sh);
  font-size:16px;
  font-weight:600;
  text-decoration:none;
  transition:transform .2s var(--ease),box-shadow .2s ease-out;
}
.menu a:nth-child(n+5){background:var(--blue)}
.menu a:hover{transform:translateY(-2px)}
.menu a:active{
  transform:translateY(2px) scale(.98);
  box-shadow:inset 2px 3px 8px rgba(23,38,32,.26);
}

main{display:block}

/* 首屏 */
.hero{
  position:relative;
  overflow:hidden;
  min-height:45vh;
  display:flex;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  gap:16px;
  padding:34px 20px 32px;
  text-align:center;
  border-bottom:3px solid var(--ink);
  background:linear-gradient(158deg,#ffffff 0%,var(--mint-s) 56%,var(--blue-s) 100%);
}

.hero::before{
  content:'片库';
  position:absolute;
  top:50%;
  left:50%;
  transform:translate(-50%,-54%);
  font-family:var(--head);
  font-size:clamp(86px,30vw,220px);
  line-height:1;
  letter-spacing:-.02em;
  color:var(--ink);
  opacity:.085;
  pointer-events:none;
}

.hero h1{
  position:relative;
  z-index:1;
  font-size:clamp(27px,7.2vw,50px);
  max-width:22ch;
  text-wrap:balance;
}

.hero-go{
  position:relative;
  z-index:1;
  display:inline-flex;
  align-items:center;
  min-height:46px;
  padding:11px 24px;
  border:var(--bd);
  border-radius:999px;
  background:var(--ink);
  color:#e8fff7;
  font-weight:600;
  text-decoration:none;
  box-shadow:inset -2px -2px 8px rgba(255,255,255,.16), 5px 6px 12px rgba(23,38,32,.28);
  transition:transform .2s var(--ease);
}
.hero-go:active{transform:translateY(2px) scale(.98)}

.hero-art{
  position:absolute;
  top:12px;
  right:12px;
  width:84px;
  height:84px;
  margin:0;
  pointer-events:none;
  z-index:1;
}
.hero-art span{
  position:absolute;
  display:block;
  border:3px solid var(--ink);
  border-radius:12px;
  box-shadow:var(--sh);
}
.hero-art span:nth-child(1){
  width:36px;height:36px;top:0;right:0;
  background:var(--mint);
  border-radius:50%;
  animation:bob 3.6s ease-in-out infinite;
}
.hero-art span:nth-child(2){
  width:26px;height:26px;top:42px;right:32px;
  background:var(--blue);
  border-radius:50%;
  animation:bob 4.4s ease-in-out infinite .4s;
}
.hero-art span:nth-child(3){
  width:16px;height:16px;top:6px;right:52px;
  background:#ffffff;
  animation:bob 3s ease-in-out infinite .8s;
}

@keyframes bob{
  0%,100%{transform:translateY(0)}
  50%{transform:translateY(-7px)}
}

/* 主体：侧栏在左 */
.stage{
  display:grid;
  grid-template-columns:minmax(0,1fr);
  gap:20px;
  align-items:start;
  max-width:1180px;
  margin:0 auto;
  padding:22px 14px 34px;
}

.rail{
  background:var(--blue-s);
  border:var(--bd);
  border-radius:var(--r);
  box-shadow:var(--sh);
  padding:14px 16px 16px;
}

.rail-k{
  margin:0 0 10px;
  font-family:var(--head);
  font-size:15px;
  letter-spacing:.16em;
  color:#2f5347;
}

.rail ul{
  list-style:none;
  margin:0;
  padding:0;
  display:grid;
  gap:8px;
}

.rail a{
  display:flex;
  align-items:center;
  min-height:42px;
  padding:8px 12px;
  border:2.5px solid var(--ink);
  border-radius:12px;
  background:#ffffff;
  box-shadow:2px 3px 0 rgba(23,38,32,.16);
  font-size:16px;
  font-weight:600;
  text-decoration:none;
  transition:transform .18s var(--ease);
}
.rail a:active{transform:translateY(2px)}

.prose{min-width:0}
.prose h2{
  font-size:clamp(22px,4.8vw,31px);
  margin:2px 0 0;
}
.prose .subtitle,
.prose div > h2 + p{
  margin:8px 0 18px;
  font-size:16px;
  color:rgba(23,38,32,.66);
}

.prose > div{
  background:#ffffff;
  border-radius:18px;
  padding:22px 18px 26px;
  margin-bottom:16px;
  box-shadow:0 8px 0 rgba(23,38,32,.05), inset 0 0 0 2px var(--mint-s);
  scroll-margin-top:196px;
}
.prose > div:nth-child(even){
  background:var(--mint-s);
  box-shadow:0 8px 0 rgba(23,38,32,.05), inset 0 0 0 2px #d5f8e9;
}
.prose > div:last-child{margin-bottom:0}

.prose div h2{
  font-size:clamp(21px,4.6vw,28px);
  margin:0 0 10px;
}
.prose div h2::before{
  content:'';
  display:inline-block;
  width:13px;
  height:13px;
  margin-right:10px;
  border:2.5px solid var(--ink);
  border-radius:5px;
  background:var(--mint);
  vertical-align:middle;
}
.prose div:nth-child(even) h2::before{background:var(--blue)}

.prose h3{
  font-size:19px;
  margin:20px 0 10px;
  color:#24463b;
}

.prose p{margin:0 0 14px}
.prose ul,.prose ol{padding-left:1.25em;margin:0 0 14px}
.prose li{margin:0 0 8px}
.prose a{text-decoration:underline;text-decoration-thickness:2px;text-underline-offset:3px;font-weight:600}

.prose img{
  display:block;
  max-width:100%;
  height:auto;
  border:3px solid var(--ink);
  border-radius:16px;
  box-shadow:var(--sh);
  margin:6px 0 16px;
}
.prose figure{margin:6px 0 16px}
.prose figure img{margin-bottom:8px}
.prose figcaption{font-size:15px;color:rgba(23,38,32,.68)}
.prose blockquote{
  margin:0 0 16px;
  padding:12px 16px;
  border-left:6px solid var(--mint);
  border-radius:0 14px 14px 0;
  background:#f2fffa;
}
.prose blockquote p:last-child{margin-bottom:0}
.prose table{
  width:100%;
  border-collapse:collapse;
  margin:0 0 16px;
  font-size:16px;
}
.prose th,.prose td{
  border:2px solid rgba(23,38,32,.24);
  padding:8px 10px;
  text-align:left;
}
.prose th{background:var(--blue-s);font-family:var(--head);font-weight:400}
.prose pre,.prose code{font-family:ui-monospace,monospace}
.prose pre{
  overflow-x:auto;
  padding:12px 14px;
  border-radius:14px;
  background:#0f1c17;
  color:#d8fff0;
  font-size:15px;
}
.prose pre code{color:inherit}

/* 页脚：两栏分区 */
.foot{
  border-top:3px solid var(--ink);
  background:linear-gradient(180deg,#e6fff7 0%,#ffffff 100%);
  padding:30px 16px 18px;
  margin-top:10px;
  display:grid;
  grid-template-columns:minmax(0,1fr);
  gap:22px;
}

.bigmark{
  font-family:var(--head);
  font-size:clamp(32px,9vw,72px);
  line-height:1.02;
  letter-spacing:-.012em;
  margin:0 0 10px;
  word-break:break-word;
}

.foot-desc{
  margin:0;
  max-width:44ch;
  font-size:16px;
  color:rgba(23,38,32,.72);
}

.foot-nav a{
  display:inline-flex;
  align-items:center;
  min-height:42px;
  padding:8px 12px;
  border:2.5px solid var(--ink);
  border-radius:12px;
  background:#ffffff;
  box-shadow:var(--sh);
  font-size:16px;
  font-weight:600;
  text-decoration:none;
}

.foot-bar{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px;
  margin-top:18px;
  padding-top:12px;
  border-top:2px dashed rgba(23,38,32,.3);
  font-size:15px;
}

.foot-bar a{
  display:inline-flex;
  align-items:center;
  min-height:40px;
  padding:8px 14px;
  border-radius:999px;
  background:var(--mint);
  border:2.5px solid var(--ink);
  font-weight:600;
  text-decoration:none;
}

/* 滚动显现 */
.rv{
  opacity:0;
  transform:translateY(16px);
  transition:opacity .52s ease-out,transform .52s var(--ease);
}
.rv.in{opacity:1;transform:none}

@media (min-width:900px){
  .stage{
    grid-template-columns:280px minmax(0,1fr);
    gap:28px;
    padding:34px 22px 56px;
  }
  .rail{position:sticky;top:186px}
  .foot{
    grid-template-columns:1.15fr 1fr;
    padding:40px 24px 22px;
    gap:30px;
  }
}

@media (max-width:640px){
  body{font-size:16px}
  .hero{min-height:auto;padding:28px 16px 26px}
  .hero-art{width:66px;height:66px;top:8px;right:8px}
  .hero-art span:nth-child(1){width:30px;height:30px}
  .hero-art span:nth-child(2){width:22px;height:22px;top:34px;right:26px}
  .hero-art span:nth-child(3){top:4px;right:42px}
  .prose > div{padding:18px 14px 22px;scroll-margin-top:210px}
  .menu a,.rail a,.foot-nav a{font-size:15.5px}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .rv{opacity:1;transform:none;transition:none}
  .hero-art span{animation:none}
}

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