:root{--bg:#f6f7f9;--surface:#fff;--surface-2:#eef1f5;--border:#e2e6ec;--border-strong:#cdd4de;--text:#161b22;--text-muted:#5b6675;--accent:#2563eb;--accent-hover:#1d4ed8;--accent-weak:#e8f0ff;--net:#2563eb;--host:#9aa7b8;--danger:#dc2626;--warn:#b45309;--sans:system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, "Hiragino Sans", "Noto Sans JP", sans-serif;--mono:ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;--radius:14px;--radius-sm:9px;--shadow-sm:0 1px 2px #1018280d;--shadow:0 1px 3px #1018280f, 0 8px 24px -8px #1018281a;--maxw:1040px;color-scheme:light}[data-theme=dark]{--bg:#0b0e14;--surface:#141922;--surface-2:#1b212c;--border:#262d39;--border-strong:#333c4a;--text:#e7edf4;--text-muted:#97a3b2;--accent:#5b93ff;--accent-hover:#7aa8ff;--accent-weak:#16243d;--net:#5b93ff;--host:#56606e;--shadow-sm:0 1px 2px #0000004d;--shadow:0 1px 3px #0000004d, 0 12px 32px -10px #00000080;color-scheme:dark}@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--bg:#0b0e14;--surface:#141922;--surface-2:#1b212c;--border:#262d39;--border-strong:#333c4a;--text:#e7edf4;--text-muted:#97a3b2;--accent:#5b93ff;--accent-hover:#7aa8ff;--accent-weak:#16243d;--net:#5b93ff;--host:#56606e;--shadow-sm:0 1px 2px #0000004d;--shadow:0 1px 3px #0000004d, 0 12px 32px -10px #00000080}}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}body{font-family:var(--sans);background:var(--bg);color:var(--text);-webkit-font-smoothing:antialiased;text-rendering:optimizelegibility;margin:0;font-size:16px;line-height:1.6}a{color:var(--accent);text-decoration:none}a:hover{color:var(--accent-hover)}.container{max-width:var(--maxw);margin:0 auto;padding:0 22px}.site-header{z-index:30;background:color-mix(in srgb, var(--surface) 88%, transparent);backdrop-filter:blur(10px)saturate(1.3);border-bottom:1px solid var(--border);position:sticky;top:0}.site-header 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var(--border);border-radius:var(--radius-sm);background:var(--surface-2);min-height:120px;color:var(--text-muted);cursor:pointer;text-align:center;justify-content:center;align-items:center;padding:24px;font-weight:600;transition:border-color .15s,background .15s,color .15s;display:flex}.dropzone:hover{border-color:var(--accent);color:var(--text)}.dropzone.over{border-color:var(--accent);background:var(--accent-weak);color:var(--accent)}.check{color:var(--text-muted);cursor:pointer;user-select:none;align-items:center;gap:8px;margin-top:12px;font-size:.92rem;display:inline-flex}.check input{width:16px;height:16px;accent-color:var(--accent);cursor:pointer}