*{box-sizing:border-box}html,body{margin:0;padding:0}
body{font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;background:#0b1220;color:#e5e7eb}
.container{max-width:900px;margin:40px auto;padding:0 16px}
.hero{margin-bottom:18px}
h1{font-size:28px;margin:0 0 6px}
.sub{margin:0;color:#9ca3af}
.card{background:#0f162a;border:1px solid #1f2a44;border-radius:16px;padding:16px;margin-bottom:18px;box-shadow:0 6px 20px rgba(0,0,0,.25)}
label{display:block;margin-bottom:8px}
.row{display:flex;gap:8px;align-items:center}
.row.between{justify-content:space-between}
input[type="url"]{flex:1;padding:12px 14px;border-radius:12px;border:1px solid #334155;background:#0b1220;color:#e5e7eb;outline:none}
button{padding:12px 16px;border:none;border-radius:12px;background:#3b82f6;color:#fff;cursor:pointer;font-weight:600}
button:hover{opacity:.95}
.hint{color:#94a3b8}
.hidden{display:none}
#cssOutput{width:100%;height:360px;margin-top:12px;padding:12px;border-radius:12px;border:1px solid #334155;background:#0b1220;color:#e5e7eb;white-space:pre;overflow:auto}
.actions{display:flex;gap:8px}
summary{cursor:pointer;margin:10px 0}
footer{opacity:.7;text-align:center;margin:24px 0 40px}
.note{color:#a3e635}
.tips ol{margin:0 0 0 1rem}
.tips code{background:#111827;border:1px solid #1f2937;padding:1px 6px;border-radius:6px}