:root{--bg:#acdaf7;--card:#fff;--text:#333;--muted:#667;--accent:#b9d3e4;--ok:#1a8a4a;--ng:#c62828;--key-shadow:0 3px 0 #9bb8cc, 0 4px 6px #0000001f}*{box-sizing:border-box}body{background:var(--bg);color:var(--text);-webkit-tap-highlight-color:transparent;margin:0;font-family:Hiragino Sans,Noto Sans JP,system-ui,sans-serif}button{font:inherit;color:inherit;cursor:pointer}.screen{max-width:440px;min-height:100dvh;margin:0 auto;padding:16px}.screen.center{align-items:center;display:flex}.card{background:var(--card);border-radius:12px;width:100%;padding:20px}h1{text-align:center;margin:0 0 12px;font-size:20px}h2{margin:16px 0 6px;font-size:16px}.note{color:var(--muted);text-align:center;margin:4px 0;font-size:13px}.error{color:var(--ng);min-height:1.2em;margin:6px 0;font-size:14px}.card button{background:#fff;border:1px solid #ccd;border-radius:10px;width:100%;margin:8px 0;padding:12px;display:block}.card button.primary,.ops .primary{background:var(--accent);border-color:var(--accent);font-weight:700}.card button:disabled{opacity:.45;cursor:default}.card button.link{color:var(--muted);border:none;font-size:13px}label{font-size:14px;display:block}input[type=email]{border:1px solid #ccd;border-radius:8px;width:100%;margin-top:6px;padding:10px;font-size:16px;display:block}.mode{border-top:1px solid #eef}.quiz{flex-direction:column;gap:10px;display:flex}.topbar button{background:#fff;border:none;border-radius:6px;padding:6px 12px;font-size:13px;box-shadow:0 2px 3px #00000026}.qcard{flex:1}.progress{color:#25c;font-weight:700}.tag{color:var(--muted);background:#eef4fa;border-radius:10px;margin-top:6px;padding:1px 8px;font-size:12px;display:inline-block}.qname{text-align:center;margin:14px 0;font-size:20px}.slots{align-items:center;gap:6px;display:flex}.slot{cursor:pointer;border:2px solid #dde;border-radius:8px;flex:1;min-width:0;padding:4px 6px}.slot.active{border-color:#25c}.slot .label{color:var(--muted);font-size:11px}.formula{overflow-wrap:anywhere;min-height:1.6em;font-size:22px}.arrow{font-size:20px}sub,sup{font-size:.65em}.feedback{border-radius:8px;margin-top:8px;padding:10px;font-size:14px}.feedback.ok{background:#e8f6ee}.feedback.ng{background:#fdecec}.verdict{font-size:18px;font-weight:700}.feedback.ok .verdict{color:var(--ok)}.feedback.ng .verdict{color:var(--ng)}.feedback dl{margin:6px 0 0}.feedback dt{color:var(--muted);margin-top:6px;font-size:12px}.feedback dd{margin:0}.score{text-align:center;font-size:28px;font-weight:700}.wrong{padding-left:20px;font-size:14px}.ops{grid-template-columns:1fr 1.2fr 1fr;align-items:center;gap:12px;display:grid}.ops button{box-shadow:var(--key-shadow);background:#fff;border:none;border-radius:8px;padding:10px 4px;font-size:14px}.ops .primary{padding:12px 4px;font-size:20px}.pad{grid-template-columns:repeat(7,1fr);gap:6px;display:grid}.pad button{aspect-ratio:1;box-shadow:var(--key-shadow);background:#fff;border:none;border-radius:10px;padding:0;font-size:20px}.pad button:active{transform:translateY(2px);box-shadow:0 1px #9bb8cc}.pad button.coef{background:#fff6dc}.pad button.sup sup{font-size:14px;position:relative;top:-.5em}.pad button.sub sub{font-size:14px;position:relative;top:.5em}.pad button.span3{aspect-ratio:auto;grid-column:span 3}.pad button.span4{aspect-ratio:auto;grid-column:span 4}.pad button.span3,.pad button.span4{min-height:40px}.pad button.blank{visibility:hidden}.pad button.small{font-size:14px}.pad.disabled{opacity:.5;pointer-events:none}.aux{justify-content:flex-end;gap:8px;margin-top:4px;display:flex}.aux[hidden]{display:none}.card .aux button{width:auto;color:var(--muted);margin:0;padding:4px 12px;font-size:13px}.feedback.peek{background:#fff7e0}.slots.stacked{flex-direction:column;align-items:stretch;gap:2px}.slots.stacked .arrow{text-align:center;line-height:1}.slots.stacked .formula{min-height:1.3em;font-size:20px}.slots.stacked .slot{padding:2px 6px}.slots.stacked .label{line-height:1.2;display:block}.quiz .qname{margin:8px 0}.mode-C .pad button{aspect-ratio:auto;height:36px}.mode-R .pad button{aspect-ratio:auto;height:32px}.mode-C .qcard,.mode-R .qcard{padding:14px 20px}.mode-C .error,.mode-R .error{margin:2px 0}.mode-C.quiz,.mode-R.quiz{gap:8px}.hintline{background:#eef4fa;border-radius:8px;margin:6px 0 0;padding:6px 10px;font-size:15px}.feedback .diag{margin:4px 0;font-size:14px;font-weight:700}.kbd-hint{color:var(--muted);margin:4px 0 0;font-size:12px}@media (hover:none){.kbd-hint{display:none}}.tabs{grid-template-columns:1fr 1fr;gap:6px;margin:8px 0;display:grid}.card .tabs button{margin:0;padding:8px;font-size:14px}.card .tabs button.on{color:#fff;background:#25c;border-color:#25c;font-weight:700}.stats{text-align:center;margin:4px 0;font-size:13px}.row{gap:8px;display:flex}.card .row button{flex:1}.admin-list{margin:8px 0 0;padding:0;list-style:none}.admin-list li{border-top:1px solid #eef;padding:8px 0}.admin-list .eq{margin:4px 0;font-size:18px}.card .admin-list button{margin:0;padding:6px;font-size:13px}.card button.danger{color:var(--ng)}.admin-form label{margin:8px 0}.admin-form label[hidden]{display:none}.admin-form input,.admin-form select,.admin-form textarea{width:100%;font:inherit;border:1px solid #ccd;border-radius:8px;margin-top:4px;padding:8px;font-size:16px;display:block}.admin-form .row label{flex:1}.admin-form .slot{margin:6px 0}.dock{background:var(--bg);margin:0 -16px;padding:8px 16px 12px;position:sticky;bottom:0;box-shadow:0 -4px 10px #0000001f}.dock[hidden]{display:none}.dock .ops{margin-bottom:8px}.admin .pad button{aspect-ratio:auto;height:38px}.preview{color:var(--ok);font-size:14px}.errors{color:var(--ng);padding-left:18px;font-size:13px}.review{border-radius:10px;padding:1px 8px;font-size:12px;font-weight:700;display:inline-block}.review-unchecked{color:var(--muted);background:#eee}.review-requested{color:#8a6100;background:#fff3cd}.review-ok{color:var(--ok);background:#e8f6ee}.review-ng{color:var(--ng);background:#fdecec}.review-note{background:#fdecec;border-radius:6px;margin:4px 0;padding:6px 8px;font-size:13px}