:root{--bg: #ffffff;--fg: #1a1a1a;--muted: #6b7280;--line: #d9dde3;--card: #f6f7f9;--accent: #2563eb;--danger: #b91c1c;color-scheme:light dark}@media (prefers-color-scheme: dark){:root{--bg: #14161a;--fg: #e8eaed;--muted: #9aa3af;--line: #2d3138;--card: #1d2026;--accent: #60a5fa;--danger: #f87171}}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.5 -apple-system,BlinkMacSystemFont,Hiragino Sans,sans-serif}.app{max-width:960px;margin:0 auto;padding:0 12px 48px}.nav{display:flex;gap:4px;padding:8px 0;border-bottom:1px solid var(--line);overflow-x:auto}.nav a{padding:6px 12px;border-radius:6px;color:var(--fg);text-decoration:none;white-space:nowrap}.nav a.active{background:var(--card);font-weight:700}h1{font-size:1.4rem;margin:16px 0 4px}h2{font-size:1.1rem;margin:8px 0}h3{font-size:1rem;margin:8px 0}a{color:var(--accent)}.stack>*+*{margin-top:12px}.row{display:flex;gap:8px;align-items:center;flex-wrap:wrap}.between{justify-content:space-between}.muted{color:var(--muted);margin:4px 0}.unread{font-weight:700}label{display:block;font-size:.9rem}label.check{display:flex;gap:6px;align-items:center}input:not([type=checkbox]),select,textarea{display:block;width:100%;margin-top:4px;padding:8px;font:inherit;color:inherit;background:var(--bg);border:1px solid var(--line);border-radius:6px}button,.button{font:inherit;padding:8px 14px;border-radius:6px;border:1px solid var(--line);background:var(--card);color:var(--fg);cursor:pointer;text-decoration:none;min-height:40px}button.small{padding:4px 10px;min-height:32px;font-size:.85rem}button.primary,.button.primary{background:var(--accent);border-color:var(--accent);color:#fff;font-weight:700}button.danger{color:var(--danger)}button.linklike{border:0;background:none;padding:0;min-height:0;color:var(--accent);text-align:left}button:disabled{opacity:.5;cursor:not-allowed}.cards{list-style:none;padding:0;margin:0;display:grid;gap:8px}.card{background:var(--card);border:1px solid var(--line);border-radius:8px;padding:10px 12px}.card.deleted{opacity:.55}.board{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}@media (max-width: 720px){.board{grid-template-columns:1fr}}.detail{border:1px solid var(--line);border-radius:8px;padding:12px;background:var(--card)}.history{padding-left:18px;margin:0;font-size:.9rem}.toast{position:fixed;left:12px;right:12px;bottom:12px;z-index:10;display:flex;gap:8px;justify-content:space-between;align-items:flex-start;padding:10px 14px;border-radius:8px;background:var(--danger);color:#fff}.toast p{margin:0}.toast .request-id{font-size:.7rem;opacity:.8}.toast>button{background:#ffffff2e;border:0;color:inherit;min-height:0;padding:4px 10px}.banner{position:sticky;top:0;z-index:10;display:flex;gap:8px;justify-content:space-between;padding:10px 14px;background:#b45309;color:#fff}.banner p,.form-error p{margin:0}.banner button{background:none;border:0;color:inherit;min-height:0;padding:0 4px}.form-error{padding:8px 12px;border:1px solid var(--danger);border-radius:6px;color:var(--danger)}.field-error{margin:4px 0 0;font-size:.85rem;color:var(--danger)}.toast button{background:none;border:0;color:inherit;min-height:0;padding:0 4px}