/* ===== V站赛场 · site.css ===== */
:root{
  --ink-900:#0A1235;
  --ink-800:#0E1842;
  --ink-700:#18265C;
  --lime:#C8FF3D;
  --lime-dim:#8FB82A;
  --orange:#FF6A2A;
  --cool-200:#D7DCE8;
  --cool-500:#747D96;
  --white:#FFFFFF;
  --black:#05070F;
  --cyan:#3DE0FF;

  --line:rgba(215,220,232,.16);
  --line-strong:rgba(215,220,232,.34);
  --cut:18px;
  --step:8px;
  --shell:1440px;
  --gutter:clamp(16px,4vw,56px);
  --font-sans:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --dur:180ms;
  --dur-fast:120ms;
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{
  margin:0;
  background:var(--ink-900);
  color:var(--cool-200);
  font-family:var(--font-sans);
  font-size:clamp(16px,.55vw + 13px,18px);
  line-height:1.75;
  font-weight:400;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
h1,h2,h3,h4{margin:0;color:var(--white);font-weight:900;letter-spacing:-.04em;line-height:1.08}
h1{font-size:clamp(2.8rem,7vw,7rem)}
h2{font-size:clamp(1.8rem,3.5vw,3.4rem)}
h3{font-size:clamp(1.15rem,1.5vw,1.6rem);letter-spacing:-.02em;line-height:1.28}
p{margin:0 0 1em}
ul,ol{margin:0;padding:0;list-style:none}
a{color:inherit;text-decoration:none}
img,svg,picture{display:block;max-width:100%}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
::selection{background:var(--lime);color:var(--ink-900)}
:focus-visible{outline:2px solid var(--cyan);outline-offset:3px}
#main-content{display:block;scroll-margin-top:140px}
[id]{scroll-margin-top:140px}

/* ===== 跳转链接 ===== */
.skip-link{
  position:fixed;top:10px;left:10px;z-index:300;
  transform:translateY(-180%);
  padding:10px 20px;
  background:var(--lime);color:var(--ink-900);
  font-weight:700;font-size:.95rem;letter-spacing:.02em;
  clip-path:polygon(0 0,calc(100% - 10px) 0,100% 10px,100% 100%,0 100%);
  transition:transform var(--dur) ease;
}
.skip-link:focus{transform:translateY(0)}

/* ===== 头部框架 ===== */
.site-header{
  position:sticky;top:0;z-index:90;
  background:rgba(10,18,53,.96);
  border-bottom:1px solid var(--line-strong);
  backdrop-filter:blur(10px);
  -webkit-backdrop-filter:blur(10px);
}
.header-rail{
  display:flex;align-items:center;gap:12px;
  height:12px;padding:0 var(--gutter);
  background:linear-gradient(90deg,rgba(200,255,61,.42),rgba(200,255,61,0) 46%);
  border-bottom:1px solid var(--line);
}
.rail-tick{width:48px;height:2px;background:var(--lime);flex:none}
.rail-bar{
  flex:1;height:1px;
  background:repeating-linear-gradient(90deg,var(--line-strong) 0 1px,transparent 1px 16px);
}
.header-frame{
  display:grid;
  grid-template-columns:auto 1fr auto;
  align-items:center;
  gap:clamp(12px,2vw,32px);
  width:100%;max-width:var(--shell);margin:0 auto;
  padding:12px var(--gutter);
}

/* 品牌 */
.brand{display:flex;align-items:center;gap:10px;flex:none}
.brand-mark{
  display:grid;place-items:center;
  width:44px;height:44px;flex:none;
  background:var(--lime);color:var(--ink-900);
  font-family:var(--font-mono);font-weight:700;font-size:1.4rem;line-height:1;
  clip-path:polygon(0 0,100% 0,100% calc(100% - 13px),calc(100% - 13px) 100%,0 100%);
}
.brand-text{display:flex;flex-direction:column;line-height:1.1}
.brand-name{font-weight:900;font-size:1.16rem;letter-spacing:-.045em;color:var(--white)}
.brand-tagline{
  margin-top:5px;
  font-family:var(--font-mono);font-size:.6rem;letter-spacing:.18em;
  color:var(--cool-500);
}
.brand:hover .brand-name{color:var(--lime)}

/* 导航 */
.site-nav{justify-self:center;min-width:0}
.nav-list{display:flex;align-items:center;gap:clamp(2px,.8vw,10px)}
.nav-item{flex:none}
.nav-link{
  position:relative;display:flex;align-items:baseline;gap:6px;
  padding:9px 11px;
  color:var(--cool-200);font-size:.94rem;font-weight:500;
  transition:color var(--dur) ease,background var(--dur) ease;
}
.nav-link::after{
  content:"";position:absolute;left:11px;right:11px;bottom:3px;height:2px;
  background:var(--lime);transform:scaleX(0);transform-origin:left;
  transition:transform var(--dur) ease;
}
.nav-link:hover{color:var(--white)}
.nav-link:hover::after{transform:scaleX(1)}
.nav-link:hover .nav-index{color:var(--lime)}
.nav-index{font-family:var(--font-mono);font-size:.6rem;letter-spacing:.08em;color:var(--cool-500)}
.nav-label{display:inline-block}
.nav-link[aria-current="page"]{
  background:var(--lime);color:var(--ink-900);font-weight:700;
}
.nav-link[aria-current="page"] .nav-index{color:rgba(10,18,53,.62)}
.nav-link[aria-current="page"]::after{display:none}

/* 动作区 */
.header-actions{display:flex;align-items:center;gap:10px;justify-self:end}
.status-chip{
  display:inline-flex;align-items:center;gap:8px;
  padding:6px 11px;
  border:1px solid var(--line-strong);
  font-family:var(--font-mono);font-size:.64rem;letter-spacing:.13em;
  color:var(--cool-200);white-space:nowrap;
}
.status-dot{
  width:7px;height:7px;flex:none;border-radius:50%;
  background:var(--orange);
  box-shadow:0 0 0 3px rgba(255,106,42,.2);
}
@media (prefers-reduced-motion:no-preference){
  .status-dot{animation:status-pulse 2.6s ease-in-out infinite}
}
@keyframes status-pulse{0%,100%{opacity:1}50%{opacity:.32}}

/* 按钮 */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:11px 22px;
  font-weight:700;font-size:.94rem;letter-spacing:.02em;
  border:1px solid transparent;
  clip-path:polygon(0 0,calc(100% - 12px) 0,100% 12px,100% 100%,0 100%);
  transition:background var(--dur) ease,color var(--dur) ease,border-color var(--dur) ease,transform var(--dur-fast) ease;
}
.btn:active{transform:translateY(1px)}
.btn-primary{background:var(--lime);color:var(--ink-900)}
.btn-primary:hover{background:var(--lime-dim)}
.btn-ghost{border-color:var(--line-strong);color:var(--white)}
.btn-ghost:hover{border-color:var(--lime);color:var(--lime)}
.btn-solid{background:var(--orange);color:var(--ink-900)}
.btn-solid:hover{background:#ff8148}
.header-cta{white-space:nowrap}

/* 移动菜单按钮 */
.nav-toggle{
  display:none;align-items:center;gap:9px;
  padding:9px 13px;
  border:1px solid var(--line-strong);
  color:var(--white);font-size:.85rem;font-weight:700;letter-spacing:.04em;
  transition:border-color var(--dur) ease,color var(--dur) ease;
}
.nav-toggle:hover{border-color:var(--lime);color:var(--lime)}
.nav-toggle-box{display:grid;gap:4px;width:18px}
.nav-toggle-bar{
  height:2px;background:var(--lime);
  transition:transform var(--dur) ease,opacity var(--dur) ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1){transform:translateY(6px) rotate(38deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3){transform:translateY(-6px) rotate(-38deg)}

/* 阅读进度 */
.scroll-meter{
  position:absolute;left:0;right:0;bottom:-1px;height:2px;
  background:transparent;pointer-events:none;
}
.scroll-meter-fill{
  display:block;height:100%;width:0;
  background:linear-gradient(90deg,var(--lime),var(--cyan));
  transition:width 90ms linear;
}

/* ===== 页脚 ===== */
.site-footer{
  margin-top:clamp(48px,8vw,96px);
  background:var(--black);
  border-top:1px solid var(--line-strong);
  color:var(--cool-200);
}
.footer-frame{
  display:grid;
  grid-template-columns:1.4fr repeat(3,minmax(110px,.8fr)) 1.3fr;
  gap:clamp(18px,3vw,40px);
  width:100%;max-width:var(--shell);margin:0 auto;
  padding:clamp(32px,5vw,64px) var(--gutter) clamp(24px,3vw,40px);
}
.footer-brand-link{
  display:inline-block;
  font-weight:900;font-size:clamp(1.35rem,2vw,1.85rem);
  letter-spacing:-.045em;color:var(--white);
  border-bottom:2px solid transparent;
  transition:color var(--dur) ease,border-color var(--dur) ease;
}
.footer-brand-link:hover{color:var(--lime);border-color:var(--lime)}
.footer-line{
  margin:12px 0 0;
  font-family:var(--font-mono);font-size:.7rem;letter-spacing:.16em;
  color:var(--cool-500);
}
.footer-note{margin:10px 0 0;font-size:.84rem;line-height:1.6;color:var(--cool-500);max-width:32ch}
.footer-col{min-width:0}
.footer-col-title{
  margin:0 0 14px;
  font-family:var(--font-mono);font-size:.66rem;font-weight:700;
  letter-spacing:.22em;color:var(--lime);
}
.footer-list li + li{margin-top:9px}
.footer-link{
  display:inline-block;font-size:.94rem;color:var(--cool-200);
  border-bottom:1px solid transparent;
  transition:color var(--dur) ease,border-color var(--dur) ease;
}
.footer-link:hover{color:var(--lime);border-color:var(--lime)}
.footer-contact{min-width:0}
.copy-line{
  display:flex;align-items:center;justify-content:space-between;gap:12px;
  width:100%;padding:9px 0;
  border-bottom:1px dashed var(--line-strong);
  font-family:var(--font-mono);font-size:.78rem;
  color:var(--cool-200);text-align:left;
  transition:color var(--dur) ease,border-color var(--dur) ease;
}
.copy-line:hover,.copy-line:focus-visible{color:var(--lime);border-color:var(--lime)}
.copy-text{overflow-wrap:anywhere}
.copy-hint{
  flex:none;
  font-size:.6rem;letter-spacing:.14em;color:var(--cool-500);
}
.copy-line:hover .copy-hint{color:var(--lime)}
.footer-address{margin:14px 0 0;font-size:.84rem;line-height:1.65;color:var(--cool-500)}
.footer-rail{
  display:flex;flex-wrap:wrap;gap:10px;
  width:100%;max-width:var(--shell);margin:0 auto;
  padding:0 var(--gutter) clamp(20px,3vw,32px);
}
.rail-chip{
  padding:6px 12px;
  border:1px solid var(--line);
  font-family:var(--font-mono);font-size:.66rem;letter-spacing:.14em;
  color:var(--cool-500);
}
.rail-chip--hot{border-color:rgba(255,106,42,.55);color:var(--orange)}
.footer-legal{
  display:flex;flex-wrap:wrap;justify-content:space-between;gap:10px;
  width:100%;max-width:var(--shell);margin:0 auto;
  padding:16px var(--gutter) 28px;
  border-top:1px solid var(--line);
  font-family:var(--font-mono);font-size:.68rem;letter-spacing:.08em;
  color:var(--cool-500);
}
.footer-legal p{margin:0}

/* ===== 页面基础容器与组件 ===== */
.wrap{width:100%;max-width:var(--shell);margin:0 auto;padding:0 var(--gutter)}
.section{padding:clamp(40px,7vw,96px) 0}
.section--tight{padding:clamp(24px,4vw,56px) 0}
.eyebrow{
  display:inline-flex;align-items:center;gap:10px;
  margin:0 0 14px;
  font-family:var(--font-mono);font-size:.68rem;letter-spacing:.24em;
  color:var(--lime);text-transform:uppercase;
}
.eyebrow::before{content:"";width:26px;height:2px;background:var(--lime)}
.lede{max-width:70ch;font-size:clamp(1rem,1.15vw,1.18rem);line-height:1.82;color:var(--cool-200)}
.grid{display:grid;gap:clamp(16px,2.4vw,32px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--4{grid-template-columns:repeat(4,minmax(0,1fr))}
.panel{
  background:var(--ink-700);
  border:1px solid var(--line);
  padding:clamp(18px,2.4vw,28px);
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,0 100%);
}
.panel--flat{background:transparent}
.panel--hot{border-color:rgba(255,106,42,.45)}
.panel--lime{border-color:rgba(200,255,61,.45)}
.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:5px 10px;
  border:1px solid var(--line-strong);
  font-family:var(--font-mono);font-size:.64rem;letter-spacing:.12em;
  color:var(--cool-200);
}
.tag--lime{border-color:var(--lime);color:var(--lime)}
.tag--orange{border-color:rgba(255,106,42,.6);color:var(--orange)}
.stat{
  display:block;
  font-family:var(--font-mono);font-weight:700;
  font-size:clamp(2rem,4vw,3.4rem);line-height:1;letter-spacing:-.02em;
  color:var(--white);
}
.stat--lime{color:var(--lime)}

/* 面包屑 */
.breadcrumbs{padding:18px 0 0}
.breadcrumbs ol{display:flex;flex-wrap:wrap;gap:8px;font-family:var(--font-mono);font-size:.68rem;letter-spacing:.1em}
.breadcrumbs li{display:flex;align-items:center;gap:8px;color:var(--cool-500)}
.breadcrumbs li + li::before{content:"/";color:var(--cool-500);opacity:.6}
.breadcrumbs a{color:var(--cool-200);border-bottom:1px solid transparent}
.breadcrumbs a:hover{color:var(--lime);border-color:var(--lime)}

/* 图片容器（页面阶段放置占位/实拍） */
.media{
  position:relative;overflow:hidden;
  background:var(--ink-700);
  border:1px solid var(--line-strong);
  clip-path:polygon(0 0,calc(100% - var(--cut)) 0,100% var(--cut),100% 100%,0 100%);
}
.media > img,.media > picture > img{width:100%;height:100%;object-fit:cover;filter:saturate(.92) contrast(1.06)}
.media--wide{aspect-ratio:16/9}
.media--tall{aspect-ratio:3/4}
.media--square{aspect-ratio:1/1}
.media--placeholder{
  display:grid;place-items:center;
  background:repeating-linear-gradient(135deg,var(--ink-700) 0 12px,var(--ink-800) 12px 24px);
}
.media--placeholder::after{
  content:attr(data-label);
  font-family:var(--font-mono);font-size:.66rem;letter-spacing:.2em;color:var(--cool-500);
}
.media__tag{
  position:absolute;left:0;top:0;z-index:2;
  padding:6px 12px;
  background:var(--lime);color:var(--ink-900);
  font-family:var(--font-mono);font-size:.64rem;font-weight:700;letter-spacing:.1em;
}
.media__caption{
  position:absolute;left:0;right:0;bottom:0;z-index:2;
  padding:16px;
  background:linear-gradient(180deg,rgba(5,7,15,0),rgba(5,7,15,.88));
  color:var(--white);font-size:.84rem;line-height:1.55;
}

/* 主题筛选按钮（页面阶段配合 data-filter-group 使用） */
.filter-bar{display:flex;flex-wrap:wrap;gap:8px}
.filter-btn{
  padding:8px 14px;
  border:1px solid var(--line-strong);
  background:transparent;color:var(--cool-200);
  font-family:var(--font-mono);font-size:.72rem;letter-spacing:.1em;
  transition:background var(--dur-fast) ease,color var(--dur-fast) ease,border-color var(--dur-fast) ease;
}
.filter-btn:hover{border-color:var(--lime);color:var(--lime)}
.filter-btn[aria-pressed="true"]{background:var(--lime);border-color:var(--lime);color:var(--ink-900);font-weight:700}
[data-filtered-out]{display:none !important}

/* 入场显现 */
html[data-js] [data-reveal]{
  opacity:0;transform:translateY(14px);
  transition:opacity .44s ease,transform .44s ease;
}
html[data-js] [data-reveal].is-in{opacity:1;transform:none}

/* ===== 响应式 ===== */
@media (max-width:1200px){
  .status-chip{display:none}
  .nav-link{padding:9px 8px;font-size:.88rem}
  .nav-index{display:none}
}
@media (max-width:1023px){
  .header-frame{grid-template-columns:1fr auto;gap:10px}
  .brand-tagline{display:none}
  .header-cta{display:none}
  .nav-toggle{display:inline-flex}
  .site-nav{
    position:absolute;left:0;right:0;top:100%;z-index:95;
    justify-self:stretch;
    background:var(--ink-800);
    border-bottom:1px solid var(--line-strong);
    border-top:1px solid var(--line);
    max-height:0;overflow:hidden;visibility:hidden;
    transition:max-height .26s ease,visibility .26s ease;
  }
  .site-nav[data-open="true"]{
    visibility:visible;
    max-height:min(78vh,560px);
    overflow-y:auto;
  }
  .nav-list{flex-direction:column;align-items:stretch;gap:0;padding:8px var(--gutter) 20px}
  .nav-link{
    justify-content:flex-start;gap:12px;
    padding:15px 4px;
    border-bottom:1px solid var(--line);
    font-size:1.05rem;
  }
  .nav-index{display:inline-block;font-size:.66rem}
  .nav-link::after{display:none}
  .nav-link[aria-current="page"]{
    background:transparent;color:var(--lime);
    border-bottom-color:rgba(200,255,61,.4);
  }
  .nav-link[aria-current="page"] .nav-index{color:var(--lime)}
  .nav-link[aria-current="page"]::before{
    content:"";width:4px;height:16px;background:var(--lime);display:inline-block;
  }

  .grid--3,.grid--4{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-frame{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-brand,.footer-contact{grid-column:1/-1}
  .footer-note{max-width:52ch}
}
@media (max-width:640px){
  .brand-mark{width:38px;height:38px;font-size:1.2rem}
  .brand-name{font-size:1.02rem}
  .nav-toggle-text{display:none}
  .header-frame{padding:10px var(--gutter)}
  .header-rail{height:9px}
  .grid--2,.grid--3,.grid--4{grid-template-columns:1fr}
  .footer-frame{grid-template-columns:1fr;gap:24px}
  .footer-legal{flex-direction:column;gap:6px}
  .media__caption{padding:12px;font-size:.78rem}
}

@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  html[data-js] [data-reveal]{opacity:1;transform:none}
}