:root {
  --bg: #0a0a0a;
  --surface: #141414;
  --border: #2a2a2a;
  --text: #e0e0e0;
  --text-dim: #888;
  --accent: #4ecdc4;
  --accent-dim: #2a9d8f;
  --radius: 12px;
  --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  --mono: 'SF Mono', 'Fira Code', 'Cascadia Code', monospace;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: var(--font); background: var(--bg); color: var(--text); min-height: 100vh; line-height: 1.6; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.container { max-width: 900px; margin: 0 auto; padding: 2rem 1.5rem; }
header { text-align: center; padding: 3rem 0 2rem; }
header h1 { font-size: 2.5rem; font-weight: 300; letter-spacing: 0.08em; margin-bottom: 0.5rem; }
header p { color: var(--text-dim); font-size: 1.1rem; }
.tools { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 1rem; margin-top: 2rem; }
.tool-card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.5rem; transition: border-color 0.2s, transform 0.2s; display: block; }
.tool-card:hover { border-color: var(--accent-dim); transform: translateY(-2px); text-decoration: none; }
.tool-card .icon { font-size: 2rem; margin-bottom: 0.75rem; }
.tool-card h3 { font-size: 1.1rem; font-weight: 500; margin-bottom: 0.25rem; color: var(--text); }
.tool-card p { font-size: 0.85rem; color: var(--text-dim); }
.tool-page { padding: 2rem 0; }
.tool-page h1 { font-size: 1.8rem; font-weight: 400; margin-bottom: 0.5rem; }
.tool-page .desc { color: var(--text-dim); margin-bottom: 2rem; }
.back { margin-bottom: 1.5rem; display: inline-block; font-size: 0.9rem; }
textarea, input[type="text"], input[type="number"], select { width: 100%; background: var(--surface); border: 1px solid var(--border); border-radius: 8px; color: var(--text); font-family: var(--mono); font-size: 0.9rem; padding: 1rem; resize: vertical; outline: none; }
textarea:focus, input:focus { border-color: var(--accent-dim); }
textarea { min-height: 200px; }
.btn { display: inline-block; background: var(--accent-dim); color: #fff; border: none; border-radius: 8px; padding: 0.6rem 1.5rem; font-size: 0.9rem; cursor: pointer; font-family: var(--font); transition: background 0.2s; margin: 0.5rem 0.5rem 0.5rem 0; }
.btn:hover { background: var(--accent); }
.output-area { background: var(--surface); border: 1px solid var(--border); border-radius: 8px; padding: 1rem; margin-top: 1rem; font-family: var(--mono); font-size: 0.85rem; white-space: pre-wrap; word-break: break-all; min-height: 100px; overflow-x: auto; }
.row { display: flex; gap: 1rem; margin-bottom: 1rem; flex-wrap: wrap; }
.row > * { flex: 1; min-width: 200px; }
footer { text-align: center; padding: 3rem 0 2rem; color: var(--text-dim); font-size: 0.8rem; }
@media (max-width: 600px) { header h1 { font-size: 1.8rem; } .tools { grid-template-columns: 1fr; } .container { padding: 1rem; } }