:root{--bg:#f5f7fb;--fg:#111827;--muted:#6b7280;--card:#fff;--line:#d1d5db;--primary:#1e3a8a;--primary-fg:#fff;--error-bg:#fef2f2;--error-fg:#991b1b;--ok-bg:#ecfdf5;--ok-fg:#065f46;--warn-bg:#fffbeb;--warn-fg:#92400e}@media (prefers-color-scheme:dark){:root{--bg:#0b1220;--fg:#e5e7eb;--muted:#9ca3af;--card:#111827;--line:#374151;--primary:#3b82f6;--error-bg:#3b0d0d;--error-fg:#fecaca;--ok-bg:#052e22;--ok-fg:#a7f3d0;--warn-bg:#3a2a05;--warn-fg:#fde68a}}*{box-sizing:border-box}html,body{margin:0;padding:0}body{background:var(--bg);color:var(--fg);font-family:system-ui,-apple-system,Hiragino Sans,Noto Sans JP,Yu Gothic UI,sans-serif;font-size:16px;line-height:1.6}a{color:var(--primary)}.container{max-width:480px;margin:0 auto;padding:32px 16px}.card{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:24px 16px}h1{margin:0 0 8px;font-size:1.5rem}.muted{color:var(--muted);font-size:.9rem}label{margin:16px 0 4px;font-weight:600;display:block}input{border:1px solid var(--line);background:var(--card);width:100%;color:var(--fg);border-radius:8px;padding:12px;font-size:16px}.button{text-align:center;background:var(--primary);width:100%;color:var(--primary-fg);cursor:pointer;border:none;border-radius:8px;margin-top:24px;padding:14px;font-size:1rem;font-weight:700;text-decoration:none;display:block}.button:disabled{opacity:.6;cursor:wait}.notice{border-radius:8px;margin-top:16px;padding:12px;font-size:.95rem}.notice.error{background:var(--error-bg);color:var(--error-fg)}.notice.ok{background:var(--ok-bg);color:var(--ok-fg)}.notice.warn{background:var(--warn-bg);color:var(--warn-fg)}