/* ============================================================
   案例页设计系统 (cases.css)
   仅 cases 路由使用（列表 + 详情），类名全部 cs- 前缀，避免与
   ec.css / home.css 冲突。风格与首页 home.css 深色 hero + 卡片
   craft 对齐：光斑 / 网格 / 渐变高亮 / hover 上浮。
   复用全站 .container/.btn/.section；动效由 main.js 自动接管
   （.section 自动加 reveal 入场、进度条、回到顶部、scrollspy）。
   ============================================================ */
:root{
  --dark:#0b1f33;
  --dark-2:#102a43;
  --accent:#F59E0B;
  --teal:#1E54E8;
}

/* ===== 列表页 Hero（深色）===== */
.cs-hero{position:relative;overflow:hidden;background:
  radial-gradient(1000px 560px at 85% -12%,rgba(30,84,232,.18),transparent 60%),
  linear-gradient(180deg,var(--dark),var(--dark-2));color:#fff;padding:66px 0 74px}
.cs-hero__bg{position:absolute;inset:0;z-index:0}
.cs-blob{position:absolute;border-radius:50%;filter:blur(60px);opacity:.5}
.cs-blob--1{width:380px;height:380px;background:var(--brand);top:-110px;left:-70px;animation:csBlobDrift 16s ease-in-out infinite}
.cs-blob--2{width:340px;height:340px;background:var(--teal);bottom:-120px;right:8%;animation:csBlobDrift 20s ease-in-out 2s infinite}
@keyframes csBlobDrift{0%,100%{transform:translate(0,0)}50%{transform:translate(24px,-20px)}}
.cs-hero__grid{position:absolute;inset:0;background-image:
  linear-gradient(rgba(255,255,255,.05) 1px,transparent 1px),
  linear-gradient(90deg,rgba(255,255,255,.05) 1px,transparent 1px);
  background-size:46px 46px;mask:radial-gradient(circle at 50% 30%,#000,transparent 75%)}
.cs-hero__inner{position:relative;z-index:1;max-width:var(--maxw);margin:0 auto;padding:0 22px}
.cs-kicker{display:inline-block;font-size:var(--fs-13);font-weight:800;letter-spacing:1px;color:#cfeffb;
  background:rgba(255,255,255,.12);border:1px solid rgba(255,255,255,.22);
  padding:7px 16px;border-radius:999px;margin-bottom:18px}
.cs-hero__title{font-size:clamp(30px,4.2vw,46px);font-weight:900;line-height:1.2;letter-spacing:-.5px;margin:0 0 14px}
.cs-hero__title em{background:linear-gradient(120deg,var(--warm),var(--accent));
  -webkit-background-clip:text;background-clip:text;color:transparent;font-style:normal;
  background-size:200% auto;animation:csShimmer 5s linear infinite}
@keyframes csShimmer{to{background-position:200% center}}
.cs-hero__sub{font-size:var(--fs-16);color:var(--brand-100);max-width:560px;line-height:1.75;margin:0}
.cs-hero__stats{display:flex;gap:38px;margin-top:36px;flex-wrap:wrap}
.cs-hero__stats b{display:block;font-size:var(--fs-26);font-weight:900;color:#fff;line-height:1}
.cs-hero__stats span{font-size:var(--fs-13);color:#a9bdd0;margin-top:4px;display:block}

/* ===== 筛选 tabs ===== */
.cs-tabs{display:flex;gap:10px;flex-wrap:wrap;margin:28px 0 30px}
.cs-tab{padding:9px 20px;border-radius:999px;font-size:var(--fs-14);font-weight:700;text-decoration:none;
  color:var(--ink-soft);background:#fff;border:1.5px solid var(--line);transition:.2s}
.cs-tab:hover{border-color:var(--brand);color:var(--brand-d)}
.cs-tab.on{background:linear-gradient(90deg,var(--brand),var(--brand-2));color:#fff;
  border-color:transparent;box-shadow:0 10px 24px -12px rgba(47,107,255,.7)}

/* ===== 案例卡片 ===== */
.cs-cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:20px}
.cs-card{display:flex;flex-direction:column;background:#fff;border:1px solid var(--line);
  border-radius:18px;padding:26px 24px;text-decoration:none;color:inherit;transition:.25s;
  position:relative;overflow:hidden}
.cs-card:hover{transform:translateY(-5px);box-shadow:var(--shadow);border-color:#c7d9f5}
.cs-card__tag{display:inline-block;font-size:var(--fs-12);font-weight:800;padding:4px 12px;
  border-radius:999px;margin-bottom:14px;align-self:flex-start}
.cs-card__tag--geo{background:#eaf1fb;color:var(--brand);border:1px solid #d4e2f7}
.cs-card__tag--social{background:#e6f7f5;color:var(--teal);border:1px solid #c9efeb}
.cs-card__tag--video{background:#fff1e8;color:#c2410c;border:1px solid #fed7aa}
.cs-card__res{font-size:var(--fs-30);font-weight:900;line-height:1.15;margin-bottom:12px;
  background:linear-gradient(120deg,var(--brand),var(--brand-2));
  -webkit-background-clip:text;background-clip:text;color:transparent}
.cs-card__title{font-size:var(--fs-19);font-weight:900;margin:0 0 8px;line-height:1.4;color:var(--ink)}
.cs-card__summary{font-size:var(--fs-14);color:var(--ink-soft);line-height:1.7;margin:0 0 18px;flex:1}
.cs-card__go{display:inline-flex;align-items:center;gap:6px;font-size:var(--fs-14);font-weight:800;color:var(--brand-d)}
.cs-card__go::after{content:"→";transition:transform .2s}
.cs-card:hover .cs-card__go::after{transform:translateX(4px)}
.cs-card__hover{position:absolute;inset:0;pointer-events:none;opacity:0;transition:opacity .3s;
  background:radial-gradient(240px circle at var(--mx,50%) var(--my,50%),rgba(47,107,255,.10),transparent 65%)}
.cs-card:hover .cs-card__hover{opacity:1}

/* ===== 文章列表卡（post 页）：升级为「博客卡」观感 =====
   原版只有 标签+标题+摘要+链接，偏空；现加分类色顶条 + 日期脚注，
   分隔与留白更克制，整体像正式的文章列表而非占位卡。 */
.cs-cards--post{gap:22px}
.cs-card--post{padding:0 0 20px;border-radius:16px;border-top-width:3px}
.cs-card--post .cs-card__tag{margin:20px 22px 0}
.cs-card--post .cs-card__title{padding:0 22px;margin:12px 22px 0 0;font-size:var(--fs-19)}
.cs-card--post .cs-card__summary{padding:0 22px;margin:0 22px 16px}
.cs-card--post .cs-card__foot{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:0 22px;margin-top:auto}
.cs-card__date{font-size:var(--fs-13);color:#9aa7b8;font-variant-numeric:tabular-nums;letter-spacing:.2px}
.cs-card--insight{border-top-color:var(--brand)}
.cs-card--news{border-top-color:var(--teal)}

/* ===== CTA 条（列表页 + 详情页共用）===== */
.cs-cta{display:flex;align-items:center;justify-content:space-between;gap:20px;flex-wrap:wrap;
  margin-top:46px;background:linear-gradient(135deg,var(--brand),var(--brand-2));color:#fff;
  border-radius:20px;padding:30px 34px;position:relative;overflow:hidden}
.cs-cta::after{content:"";position:absolute;right:-60px;top:-60px;width:220px;height:220px;border-radius:50%;
  background:rgba(255,255,255,.08)}
.cs-cta b{display:block;font-size:var(--fs-20);font-weight:900;margin-bottom:6px}
.cs-cta span{font-size:var(--fs-15);opacity:.92}
.cs-cta .btn{background:#fff;color:var(--brand-d);position:relative;z-index:1;font-weight:800}
.cs-cta .btn:hover{transform:translateY(-2px);box-shadow:0 14px 30px -14px rgba(13,27,42,.5)}

/* ===== 详情页 Hero（深色）===== */
.cs-detail-hero{position:relative;overflow:hidden;background:
  radial-gradient(800px 420px at 80% -10%,rgba(30,84,232,.16),transparent 60%),
  linear-gradient(180deg,var(--dark),var(--dark-2));color:#fff;padding:58px 0 60px}
.cs-detail-hero .cs-hero__inner{padding-top:0}
.cs-detail-hero h1{font-size:clamp(22px,3.2vw,34px);font-weight:900;line-height:1.3;margin:12px 0 12px;position:relative}
.cs-detail-hero p{color:var(--brand-100);font-size:var(--fs-16);margin:0;position:relative;max-width:720px;line-height:1.75}

/* ===== 详情 · 三栏流程 ===== */
.cs-flow{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:20px}
.cs-fi{background:#fff;border:1px solid var(--line);border-radius:16px;padding:26px 24px;transition:.25s}
.cs-fi:hover{transform:translateY(-3px);box-shadow:var(--shadow)}
.cs-fi__ic{font-size:var(--fs-28);display:block;margin-bottom:12px}
.cs-fi b{display:block;font-size:var(--fs-17);font-weight:900;color:var(--ink);margin-bottom:8px}
.cs-fi p{font-size:var(--fs-15);color:var(--ink-soft);line-height:1.7;margin:0}
.cs-fi--result{background:#ecfdf5;border-color:var(--ok-soft)}
.cs-fi--result b{color:var(--ok-d)}
.cs-fi--result p{color:var(--ok-d);font-weight:600}

/* ===== 返回按钮 ===== */
.cs-back{display:inline-block;margin-top:18px;background:#e2e8f0;color:#334155;
  border-radius:12px;padding:11px 22px;font-weight:700;text-decoration:none;transition:.2s}
.cs-back:hover{background:#cbd5e1;transform:translateX(-2px)}

/* ===== 文章正文（post 详情页）===== */
.cs-article{background:#fff;border:1px solid var(--line);border-radius:18px;padding:36px 40px;
  font-size:var(--fs-16);line-height:2;color:var(--ink);max-width:860px}
.cs-article p{margin:0 0 1.1em}
.cs-article p:last-child{margin-bottom:0}
@media (max-width:760px){.cs-article{padding:24px 20px;font-size:var(--fs-16)}}

/* ===== 空态 ===== */
.cs-empty{color:#94a3b8;text-align:center;padding:40px 0}

/* ===== 响应式 ===== */
@media (max-width:920px){
  .cs-flow{grid-template-columns:1fr 1fr}
}
@media (max-width:760px){
  .cs-hero{padding:50px 0 56px}
  .cs-hero__stats{gap:22px}
  .cs-hero__stats b{font-size:var(--fs-22)}
  .cs-cards{grid-template-columns:1fr}
  .cs-flow{grid-template-columns:1fr}
  .cs-cta{flex-direction:column;align-items:flex-start;padding:26px 24px}
  .cs-cta .btn{width:100%;text-align:center}
}
@media (prefers-reduced-motion: reduce){
  .cs-hero__title em,.cs-blob--1,.cs-blob--2{animation:none}
}