:root{--lab-accent:#16745b;--lab-soft:#eef8f4}
body{background:#fbfbfc}
.lab-shell{width:min(1260px,calc(100% - 32px));margin:auto;padding:38px 0 70px}
.lab-hero{display:grid;grid-template-columns:1fr auto;align-items:end;gap:20px;margin-bottom:24px}
.lab-kicker{margin:0 0 8px;color:var(--lab-accent);font-size:13px;font-weight:900;letter-spacing:.1em}
.lab-hero h1{margin:0;font-size:clamp(38px,6vw,68px);letter-spacing:-.05em}
.lab-hero p{max-width:850px;margin:12px 0 0;color:#667083;font-size:16px;line-height:1.75}
.lab-count{min-width:110px;padding:15px 18px;border-radius:18px;color:var(--lab-accent);background:var(--lab-soft);text-align:center}.lab-count b{display:block;font-size:30px}.lab-count small{font-weight:800}
.lab-toolbar{display:grid;grid-template-columns:minmax(220px,1fr) minmax(220px,320px);gap:10px;margin-bottom:18px;padding:13px;border:1px solid #e1e5ea;border-radius:17px;background:#fff}
.lab-toolbar input,.lab-toolbar select{width:100%;padding:12px 14px;border:1px solid #d7dde5;border-radius:11px;background:#fff;color:#1b2433;font:inherit}
.lab-toolbar input:focus,.lab-toolbar select:focus{outline:3px solid color-mix(in srgb,var(--lab-accent) 18%,transparent);border-color:var(--lab-accent)}
.lab-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:15px}
.experiment-card{overflow:hidden;border:1px solid #e0e4e9;border-radius:22px;background:#fff;box-shadow:0 8px 25px rgba(34,48,68,.05)}
.experiment-head{display:flex;justify-content:space-between;gap:12px;padding:20px 20px 12px}.experiment-head h2{margin:5px 0 0;font-size:22px;line-height:1.35}.chapter-tag{color:var(--lab-accent);font-size:11px;font-weight:900}.experiment-number{display:grid;place-items:center;width:38px;height:38px;flex:0 0 auto;border-radius:12px;color:var(--lab-accent);background:var(--lab-soft);font-weight:900}
.bench{margin:0 20px 16px;padding:14px;border:1px solid #e5e8ed;border-radius:17px;background:linear-gradient(180deg,#f9fbfd,#f2f5f8)}
.bench-title{margin-bottom:10px;color:#667083;font-size:11px;font-weight:900}
.apparatus-row,.reagent-row{display:flex;gap:8px;overflow-x:auto;padding:2px 0 7px}
.apparatus-item{min-width:78px;display:grid;justify-items:center;gap:5px;padding:9px 5px;border-radius:11px;background:#fff;box-shadow:0 3px 10px rgba(41,55,73,.07)}
.apparatus-icon{width:44px;height:44px;display:grid;place-items:center;border:2px solid #91a1b4;border-radius:12px 12px 16px 16px;color:var(--lab-accent);font-size:20px;font-weight:900}
.apparatus-item small{max-width:82px;color:#535f70;font-size:9px;text-align:center;line-height:1.35}
.reagent-item{position:relative;min-width:83px;padding:28px 7px 8px;border:1px solid #dce2e9;border-radius:9px 9px 13px 13px;background:linear-gradient(135deg,#fff,#f1f6fb);color:#354052;font-size:10px;font-weight:800;text-align:center;line-height:1.35}
.reagent-item::before{content:"";position:absolute;left:50%;top:5px;width:28px;height:12px;transform:translateX(-50%);border-radius:4px 4px 2px 2px;background:var(--lab-accent);opacity:.65}
.expand-btn{width:calc(100% - 40px);margin:0 20px 18px;padding:11px;border:0;border-radius:11px;color:var(--lab-accent);background:var(--lab-soft);font-weight:900;cursor:pointer}.expand-btn:hover{filter:brightness(.98)}
.experiment-details{display:grid;gap:13px;padding:0 20px 20px;border-top:1px solid #e7e9ed}.experiment-details[hidden]{display:none}
.detail-section{padding-top:15px}.detail-section h3{margin:0 0 8px;font-size:14px}.detail-section ul{display:grid;gap:6px;margin:0;padding-left:19px;color:#4e5969;font-size:13px;line-height:1.65}
.detail-box{padding:12px 13px;border-radius:12px;color:#445064;background:#f5f7fa;font-size:13px;line-height:1.7}.detail-box strong{color:#172033}
.equation-list{display:grid;gap:7px}.equation-line{overflow-x:auto;padding:11px 12px;border-left:3px solid var(--lab-accent);border-radius:8px;background:var(--lab-soft);font-family:"Times New Roman","Songti SC",serif;font-size:15px;line-height:1.6;white-space:nowrap}.equation-line sub{font-size:.68em}.equation-line sup{font-size:.68em}
.safety{color:#8f4c28;background:#fff4ea}.empty{grid-column:1/-1;padding:65px 20px;border:1px dashed #ccd3dc;border-radius:20px;color:#697486;background:#fff;text-align:center}
.lab-source{margin-top:18px;padding:13px 15px;border-radius:12px;color:#667083;background:#f2f4f7;font-size:12px;line-height:1.7}
@media(max-width:900px){.lab-grid{grid-template-columns:1fr}.lab-hero{grid-template-columns:1fr}.lab-count{justify-self:start}}
@media(max-width:600px){.lab-shell{width:min(100% - 20px,1260px);padding-top:25px}.lab-toolbar{grid-template-columns:1fr}.experiment-head{padding:16px 15px 10px}.bench{margin:0 15px 14px}.expand-btn{width:calc(100% - 30px);margin:0 15px 15px}.experiment-details{padding:0 15px 16px}}