:root{--bg:#f6f7fb;--card:#fff;--text:#111827;--muted:#6b7280;--line:#eef0f6;--primary:#16a34a;--primaryDark:#15803d;--shadow:0 10px 25px rgba(17,24,39,.06);--r:14px}
*{box-sizing:border-box}
body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif;background:var(--bg);color:var(--text)}
a{color:inherit;text-decoration:none}
.wrap{max-width:980px;margin:0 auto;padding:18px}
.top{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:10}
.top .wrap{display:flex;align-items:center;justify-content:space-between}
.brand{font-weight:900}
.nav a{color:var(--muted);font-weight:700}
h1{margin:14px 0 6px;font-size:28px}
.sub{margin:0 0 14px;color:var(--muted);font-weight:650}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);box-shadow:var(--shadow);padding:16px}
.tabs{display:flex;gap:10px;margin-bottom:12px}
.tab{padding:10px 12px;border:1px solid var(--line);border-radius:999px;background:#fff;font-weight:950;color:var(--muted);cursor:pointer}
.tab.active{border-color:var(--primary);color:var(--primary)}
.panel.hidden{display:none}
.display{font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-weight:950;font-size:44px;letter-spacing:.5px;text-align:center;background:#f3f4f6;border:1px solid var(--line);border-radius:14px;padding:18px;margin:12px 0}
.row{display:flex;gap:10px;flex-wrap:wrap;align-items:end}
.center{justify-content:center}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:11px 14px;border-radius:12px;border:1px solid var(--line);background:#fff;cursor:pointer;font-weight:900}
.btn.primary{background:var(--primary);border-color:var(--primary);color:#fff}
.btn.primary:hover{background:var(--primaryDark);border-color:var(--primaryDark)}
.btn.ghost{background:#fff}
.btn:disabled{opacity:.55;cursor:not-allowed}
.opt{display:flex;flex-direction:column;gap:6px}
.lbl{font-size:12px;font-weight:900;color:var(--muted)}
input{padding:10px 12px;border:1px solid var(--line);border-radius:12px;background:#fff;outline:none;width:130px}
.box{border:1px solid var(--line);border-radius:12px;background:#fff;padding:12px;margin-top:12px}
.t{font-weight:900;margin-bottom:8px}
.laps{font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-weight:800;white-space:pre-wrap;line-height:1.7}
.status{margin:10px 0;color:var(--muted);font-weight:800}
.note{margin-top:10px;color:var(--muted);font-weight:750}
.seo{margin-top:16px;border-top:1px solid var(--line);padding-top:14px}
.seo h2{margin:14px 0 8px;font-size:18px}
.seo h3{margin:12px 0 6px;font-size:15px}
.seo p{font-weight:650;line-height:1.55}
@media(max-width:520px){.display{font-size:34px} input{width:100px}}