:root{
  color-scheme:dark;
  --bg:#050811;--surface:#0a101d;--surface-2:#0e1728;--surface-3:#121e33;
  --line:#223047;--line-soft:rgba(148,163,184,.16);--text:#f7f9fd;--muted:#92a3ba;
  --cyan:#34d6e8;--blue:#5b8cff;--violet:#9a63ff;--gold:#ffd166;--green:#49df9c;--red:#ff7188;
  --shadow:0 24px 70px rgba(0,0,0,.35);--radius:22px
}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:radial-gradient(circle at 15% -10%,rgba(91,140,255,.14),transparent 34%),radial-gradient(circle at 92% 14%,rgba(154,99,255,.12),transparent 30%),var(--bg);color:var(--text);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;min-width:300px}button,input,select{font:inherit}button,a{touch-action:manipulation}.fc-top{height:76px;position:sticky;top:0;z-index:100;display:flex;align-items:center;justify-content:space-between;gap:20px;padding:0 clamp(14px,3vw,42px);border-bottom:1px solid rgba(148,163,184,.13);background:rgba(5,8,17,.82);backdrop-filter:blur(20px)}.fc-brand{display:flex;align-items:center;gap:12px;color:#fff;text-decoration:none;min-width:0}.fc-brand>span:last-child{display:grid;line-height:1.1}.fc-brand b{font-size:14px;letter-spacing:.04em}.fc-brand small{margin-top:5px;color:var(--muted);font-size:11px}.fc-mark{width:44px;height:44px;border-radius:14px;display:grid;place-items:center;font-size:24px;font-weight:900;color:#06121a;background:linear-gradient(135deg,var(--cyan),var(--blue),var(--violet));box-shadow:0 12px 34px rgba(91,140,255,.24)}.fc-top nav{display:flex;gap:6px}.fc-top nav a{color:var(--muted);text-decoration:none;padding:10px 13px;border-radius:11px;font-size:13px;font-weight:700}.fc-top nav a:hover{color:#fff;background:rgba(255,255,255,.07)}.menu-btn{display:none;border:1px solid var(--line);background:var(--surface);color:#fff;border-radius:11px;width:42px;height:42px}.fc-shell{width:min(1680px,100%);margin:auto;padding:clamp(16px,3vw,42px)}.eyebrow{margin:0 0 9px;color:var(--cyan);font-size:10px;font-weight:900;letter-spacing:.19em}.hero{position:relative;overflow:hidden;min-height:460px;padding:clamp(28px,5vw,70px);display:grid;grid-template-columns:minmax(0,1.15fr) minmax(360px,.85fr);align-items:center;gap:40px;border:1px solid var(--line-soft);border-radius:34px;background:linear-gradient(135deg,rgba(14,25,44,.97),rgba(7,14,26,.96)),repeating-linear-gradient(90deg,transparent 0 64px,rgba(255,255,255,.02) 65px);box-shadow:var(--shadow)}.hero:before{content:"";position:absolute;width:420px;height:420px;right:-140px;top:-180px;border-radius:50%;background:radial-gradient(circle,rgba(52,214,232,.19),transparent 66%)}.hero:after{content:"ƒ(x)";position:absolute;right:-24px;bottom:-92px;font:900 250px/1 Georgia,serif;color:rgba(255,255,255,.025);transform:rotate(-8deg)}.hero-copy,.hero-stats{position:relative;z-index:1}.hero h1{max-width:920px;margin:0 0 24px;font-size:clamp(48px,7vw,100px);line-height:.93;letter-spacing:-.065em}.hero h1 span{display:block;color:transparent;-webkit-text-stroke:1.4px rgba(255,255,255,.8)}.lead{max-width:820px;margin:0;color:#c5d0df;font-size:16px;line-height:1.75}.hero-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:28px}.hero-actions a,.hero-actions button{min-height:46px;padding:0 16px;display:inline-flex;align-items:center;border:1px solid var(--line);border-radius:13px;background:rgba(255,255,255,.04);color:#fff;text-decoration:none;font-weight:800;cursor:pointer}.hero-actions button{border:0;background:linear-gradient(135deg,#168d95,#506ef0);box-shadow:0 12px 28px rgba(52,214,232,.15)}.hero-stats{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.hero-stats article{min-height:110px;padding:20px;border:1px solid rgba(255,255,255,.1);border-radius:20px;background:rgba(5,11,21,.65);display:flex;flex-direction:column;justify-content:flex-end}.hero-stats strong{font-size:32px;letter-spacing:-.04em;color:var(--gold)}.hero-stats span{margin-top:4px;color:var(--muted);font-size:12px}.scientific{margin:22px 0;padding:26px;display:grid;grid-template-columns:minmax(260px,.7fr) minmax(460px,1.3fr);gap:28px;align-items:center;border:1px solid var(--line-soft);border-radius:26px;background:linear-gradient(145deg,rgba(14,23,40,.98),rgba(8,13,24,.98));box-shadow:0 18px 55px rgba(0,0,0,.2)}.scientific h2{margin:0 0 10px;font-size:clamp(28px,4vw,46px);letter-spacing:-.04em}.scientific-copy>p:not(.eyebrow){color:var(--muted);line-height:1.65}.scientific code{color:var(--cyan)}.angle-switch{display:inline-flex;padding:4px;border:1px solid var(--line);border-radius:12px;background:#060b15}.angle-switch button{border:0;border-radius:8px;padding:8px 14px;background:transparent;color:var(--muted);font-size:12px;font-weight:900;cursor:pointer}.angle-switch button.active{background:linear-gradient(135deg,var(--cyan),var(--blue));color:#06101a}.science-calculator{padding:18px;border:1px solid var(--line);border-radius:20px;background:#070c16}.science-calculator>label{display:block;margin-bottom:7px;color:var(--muted);font-size:11px;font-weight:800;text-transform:uppercase;letter-spacing:.13em}.science-display{display:grid;grid-template-columns:1fr auto;border:1px solid var(--line);border-radius:13px;background:#040812;overflow:hidden}.science-display input{min-width:0;padding:15px;border:0;outline:0;background:transparent;color:#fff;font-family:"Cambria Math",Consolas,monospace;font-size:18px}.science-display button{width:48px;border:0;border-left:1px solid var(--line);background:transparent;color:var(--muted);cursor:pointer}.science-calculator>small{display:block;margin:7px 2px;color:#71839b;font-size:11px}.science-calculator output{min-height:54px;margin:12px 0;padding:12px 15px;display:flex;align-items:center;justify-content:flex-end;border-radius:13px;background:linear-gradient(135deg,rgba(52,214,232,.08),rgba(91,140,255,.07));border:1px solid rgba(52,214,232,.18);color:var(--gold);font-size:24px;font-weight:900;overflow:auto}.science-keys{display:grid;grid-template-columns:repeat(5,1fr);gap:7px}.science-keys button{min-height:42px;border:1px solid var(--line);border-radius:10px;background:#0d1727;color:#eef4ff;font-weight:800;cursor:pointer}.science-keys button:hover{border-color:var(--cyan);background:#14243a}.science-keys .operator{color:var(--cyan)}.science-keys .utility{color:var(--red)}.science-keys .equals{background:linear-gradient(135deg,#218e97,#526df0);border:0}.workspace{display:grid;grid-template-columns:290px 340px minmax(440px,1fr);gap:16px;align-items:start}.panel{border:1px solid var(--line-soft);border-radius:var(--radius);background:rgba(10,16,29,.94);box-shadow:0 16px 50px rgba(0,0,0,.16)}.category-panel,.formula-panel{position:sticky;top:92px;max-height:calc(100vh - 112px);min-height:720px;padding:18px;overflow:auto}.calculator-panel{min-height:720px;padding:clamp(20px,3vw,34px)}.panel-head{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:15px}.panel-head h2{margin:0;font-size:20px}.icon-btn,.panel-head>button,.formula-tools button{border:1px solid var(--line);border-radius:10px;background:#070c16;color:var(--muted);padding:8px 10px;cursor:pointer}.icon-btn{width:40px;height:40px;color:var(--gold);font-size:22px}.domain-tabs{display:grid;grid-template-columns:1fr 1fr;gap:7px;margin-bottom:14px}.domain-tabs button{min-height:40px;padding:8px;border:1px solid var(--line);border-radius:11px;background:#080e1a;color:var(--muted);font-size:12px;font-weight:800;cursor:pointer}.domain-tabs button span{display:block;margin-top:3px;font-size:10px;opacity:.75}.domain-tabs button.active{border-color:transparent;background:linear-gradient(135deg,#1a8e97,#536cf0);color:#fff}.search-box{position:relative;display:flex;align-items:center;margin:10px 0 14px;border:1px solid var(--line);border-radius:12px;background:#060b15}.search-box>span{position:absolute;left:13px;color:#778aa3}.search-box input{width:100%;height:46px;padding:0 42px 0 38px;border:0;outline:0;background:transparent;color:#fff;font-size:13px}.search-box input::placeholder{color:#65758c}.search-box button{position:absolute;right:6px;width:32px;height:32px;border:0;border-radius:8px;background:transparent;color:#788aa2;cursor:pointer}.search-box button:hover{background:rgba(255,255,255,.07);color:#fff}.select-label{display:grid;gap:7px;color:var(--muted);font-size:11px;font-weight:800;text-transform:uppercase;letter-spacing:.08em}.select-label select{height:43px;padding:0 12px;border:1px solid var(--line);border-radius:11px;background:#060b15;color:#fff}.category-list,.formula-list{display:grid;gap:7px}.category-item,.formula-item,.history-entry{width:100%;border:1px solid transparent;border-radius:12px;background:#090f1b;color:#fff;text-align:left;cursor:pointer}.category-item{padding:11px}.category-item:hover,.category-item.active,.formula-item:hover,.formula-item.active{border-color:rgba(52,214,232,.65);background:#101d30}.category-item .row,.formula-item .row{display:flex;align-items:flex-start;justify-content:space-between;gap:8px}.category-item b,.formula-item b{font-size:13px}.category-item small,.formula-item small{display:block;margin-top:4px;color:var(--muted);font-size:11px;line-height:1.4}.category-item em{min-width:30px;padding:4px 7px;border-radius:999px;background:rgba(91,140,255,.12);color:#b9cbff;font-size:10px;font-style:normal;text-align:center}.count-pill{min-width:40px;padding:7px 9px;border:1px solid rgba(52,214,232,.22);border-radius:999px;background:rgba(52,214,232,.08);color:var(--cyan);font-size:12px;text-align:center}.formula-tools{display:flex;gap:7px;margin-bottom:12px}.formula-tools button{flex:1;font-size:11px}.formula-item{padding:12px}.formula-item .meta{display:flex;gap:5px;flex-wrap:wrap;margin-top:8px}.formula-item .meta span{padding:4px 6px;border-radius:999px;background:rgba(154,99,255,.1);color:#cdb8ff;font-size:9px}.formula-item em{color:var(--gold);font-style:normal}.loading-card,.empty-list{padding:30px 14px;border:1px dashed var(--line);border-radius:13px;color:var(--muted);text-align:center;font-size:13px}.empty-state{min-height:650px;display:grid;place-content:center;text-align:center;color:var(--muted)}.empty-state .orb{width:104px;height:104px;margin:0 auto 16px;display:grid;place-items:center;border:1px solid rgba(52,214,232,.22);border-radius:50%;background:radial-gradient(circle,#183c52,#081221 68%);color:var(--cyan);font-size:48px;box-shadow:0 0 70px rgba(52,214,232,.13)}.empty-state h2{margin:0 0 8px;color:#fff}.empty-state p{max-width:430px;line-height:1.6}.detail-head{display:flex;justify-content:space-between;gap:18px}.detail-head h2{margin:0 0 8px;font-size:clamp(30px,4vw,50px);letter-spacing:-.045em;line-height:1.05}.detail-head p:not(.eyebrow){margin:0;color:var(--muted);line-height:1.6}.favorite-btn{flex:0 0 auto;width:48px;height:48px;border:1px solid var(--line);border-radius:13px;background:#070c16;color:var(--gold);font-size:25px;cursor:pointer}.formula-banner{margin:22px 0;padding:20px;display:grid;gap:7px;border:1px solid rgba(52,214,232,.2);border-radius:17px;background:linear-gradient(90deg,rgba(52,214,232,.08),rgba(91,140,255,.04))}.formula-banner span{color:var(--cyan);font-size:9px;font-weight:900;letter-spacing:.18em}.formula-banner strong{font-family:"Cambria Math",Georgia,serif;font-size:clamp(20px,2.5vw,29px);overflow-wrap:anywhere}.input-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.input-field{display:grid;gap:7px}.input-field>span{color:#cbd5e1;font-size:12px;font-weight:700}.input-field input{width:100%;height:46px;padding:0 12px;border:1px solid var(--line);border-radius:11px;outline:0;background:#060b15;color:#fff;font-size:15px}.input-field input:focus{border-color:var(--cyan);box-shadow:0 0 0 3px rgba(52,214,232,.1)}.input-field small{color:#71839b;font-size:10px;line-height:1.35}.calc-actions{display:flex;flex-wrap:wrap;gap:8px;margin:18px 0}.calc-actions button{min-height:43px;padding:0 14px;border:1px solid var(--line);border-radius:11px;background:#080f1b;color:#fff;font-weight:800;cursor:pointer}.calc-actions .primary{border:0;background:linear-gradient(135deg,#198f96,#536df0)}.calc-actions button:disabled{opacity:.45;cursor:not-allowed}.result-box{margin:16px 0 24px;padding:22px;display:grid;grid-template-columns:minmax(0,1fr) auto;align-items:end;gap:6px;border:1px solid var(--line);border-left:5px solid var(--gold);border-radius:16px;background:#060b15}.result-box[data-state="success"]{border-left-color:var(--green)}.result-box[data-state="error"]{border-left-color:var(--red)}.result-box span{grid-column:1/-1;color:var(--muted);font-size:10px;font-weight:900;letter-spacing:.14em;text-transform:uppercase}.result-box strong{color:var(--gold);font-size:clamp(27px,4vw,50px);letter-spacing:-.035em;overflow-wrap:anywhere}.result-box small{padding-bottom:7px;color:var(--muted)}.explain-grid{display:grid;grid-template-columns:1.15fr .85fr;gap:13px}.explain-grid article{padding:17px;border:1px solid var(--line-soft);border-radius:15px;background:#090f1b}.explain-grid h3{margin:0 0 11px;font-size:15px}.explain-grid p,.step{color:var(--muted);font-size:12px;line-height:1.62}.step{padding:10px 0;border-bottom:1px solid rgba(148,163,184,.1)}.step:last-child{border-bottom:0}.step b{color:#e7eef9}.tags{display:flex;flex-wrap:wrap;gap:6px}.tags span{padding:6px 8px;border-radius:999px;background:rgba(52,214,232,.09);color:var(--cyan);font-size:10px}.lower-grid{display:grid;grid-template-columns:1.15fr .85fr;gap:16px;margin-top:16px}.history-panel,.coverage-panel{padding:22px}.history-list{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:9px}.history-entry{padding:13px}.history-entry strong{display:block;font-size:12px}.history-entry span{display:block;margin-top:5px;color:var(--gold);font-size:13px;font-weight:800}.history-entry small{display:block;margin-top:5px;color:var(--muted);font-size:9px}.coverage-panel>p:not(.eyebrow){color:var(--muted);line-height:1.65}.coverage-panel h2{margin-top:0}.coverage-links{display:grid;grid-template-columns:1fr 1fr;gap:8px}.coverage-links a{padding:11px;border:1px solid var(--line);border-radius:10px;color:#dbeafe;text-decoration:none;font-size:11px}.coverage-links a:hover{border-color:var(--cyan);color:#fff}.muted{color:var(--muted)}.toast{position:fixed;right:20px;bottom:20px;z-index:500;max-width:min(420px,calc(100vw - 30px));padding:13px 17px;border-radius:12px;background:#f8fafc;color:#07111f;font-size:13px;font-weight:800;box-shadow:var(--shadow);opacity:0;transform:translateY(14px);pointer-events:none;transition:.2s}.toast.show{opacity:1;transform:none}
@media(max-width:1320px){.workspace{grid-template-columns:270px 310px minmax(390px,1fr)}.history-list{grid-template-columns:1fr 1fr}}
@media(max-width:1080px){.hero{grid-template-columns:1fr}.hero-stats{grid-template-columns:repeat(3,1fr)}.scientific{grid-template-columns:1fr}.workspace{grid-template-columns:280px 1fr}.category-panel{position:sticky}.formula-panel{position:static;max-height:none;min-height:0}.calculator-panel{grid-column:1/-1;min-height:0}.formula-list{max-height:500px;overflow:auto}.lower-grid{grid-template-columns:1fr}}
@media(max-width:760px){.fc-top nav{display:none;position:absolute;left:12px;right:12px;top:68px;padding:10px;flex-direction:column;border:1px solid var(--line);border-radius:15px;background:#0b1321;box-shadow:var(--shadow)}.fc-top nav.open{display:flex}.menu-btn{display:block}.fc-shell{padding:12px}.hero{padding:28px 20px;border-radius:24px}.hero h1{font-size:52px}.hero-stats{grid-template-columns:1fr 1fr}.scientific{padding:18px}.science-keys{grid-template-columns:repeat(5,1fr)}.workspace{grid-template-columns:1fr}.category-panel,.formula-panel{position:static;max-height:none;min-height:0}.category-list,.formula-list{max-height:430px;overflow:auto}.calculator-panel{grid-column:auto}.input-grid,.explain-grid{grid-template-columns:1fr}.history-list{grid-template-columns:1fr}.coverage-links{grid-template-columns:1fr}}
@media(max-width:460px){.fc-top{height:66px;padding:0 11px}.fc-brand small{display:none}.hero h1{font-size:44px}.hero-stats{grid-template-columns:1fr}.scientific h2{font-size:32px}.science-keys{gap:5px}.science-keys button{min-height:39px;font-size:12px}.domain-tabs{grid-template-columns:1fr}.detail-head h2{font-size:31px}.result-box{grid-template-columns:1fr}.result-box small{padding:0}.calc-actions button{width:100%}}