:root { --bg: #f7f7f8; --card: #fff; --ink: #18181b; --dim: #71717a; --line: #e4e4e7; --accent: #4f46e5; --danger: #dc2626; --r: 12px; color-scheme: light dark; }
@media (prefers-color-scheme: dark) { :root { --bg: #0b0b0e; --card: #17171c; --ink: #f4f4f5; --dim: #a1a1aa; --line: #2a2a31; --accent: #818cf8; --danger: #f87171; } }
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 15px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans", sans-serif; }
.shell { min-height: 100vh; display: grid; place-content: center; gap: 18px; padding: 24px 16px; }
.brand { display: flex; align-items: center; gap: 10px; justify-content: center; font-weight: 600; font-size: 17px; }
.card { width: min(400px, calc(100vw - 32px)); background: var(--card); border: 1px solid var(--line); border-radius: 18px; padding: 28px; box-shadow: 0 10px 30px rgba(0,0,0,.06); }
h1 { font-size: 22px; margin: 0 0 4px; letter-spacing: -.01em; }
h2 { font-size: 15px; margin: 22px 0 8px; }
.dim { color: var(--dim); margin: 0 0 16px; font-size: 14px; }
label { display: block; font-size: 13px; font-weight: 500; margin: 12px 0 6px; }
input { width: 100%; font: inherit; padding: 11px 12px; border: 1px solid var(--line); border-radius: var(--r); background: transparent; color: var(--ink); }
input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 25%, transparent); }
input.code { letter-spacing: .3em; font-size: 20px; text-align: center; font-variant-numeric: tabular-nums; }
button, .btn { font: inherit; border: 1px solid var(--line); border-radius: var(--r); background: var(--card); color: var(--ink); padding: 10px 14px; cursor: pointer; font-weight: 500; text-decoration: none; display: inline-flex; justify-content: center; align-items: center; }
button.big, .btn.big { width: 100%; min-height: 46px; margin-top: 12px; }
.primary { background: var(--ink); color: var(--card); border-color: var(--ink); }
button:disabled { opacity: .6; cursor: default; }
button.busy::after { content: ''; width: 14px; height: 14px; margin-left: 8px; border: 2px solid currentColor; border-right-color: transparent; border-radius: 99px; animation: spin .7s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
button.link { border: 0; background: none; padding: 4px 0; color: var(--accent); }
button.link.danger { color: var(--danger); }
.or { display: flex; align-items: center; gap: 10px; color: var(--dim); font-size: 12px; margin: 16px 0 4px; }
.or::before, .or::after { content: ''; flex: 1; border-top: 1px solid var(--line); }
.row { display: flex; justify-content: space-between; margin-top: 12px; }
.err { background: color-mix(in srgb, var(--danger) 10%, transparent); color: var(--danger); border: 1px solid color-mix(in srgb, var(--danger) 35%, transparent); padding: 10px 12px; border-radius: var(--r); font-size: 14px; margin-bottom: 8px; }
.keys { display: grid; gap: 8px; margin-bottom: 10px; }
.key { display: flex; justify-content: space-between; align-items: center; gap: 10px; border: 1px solid var(--line); border-radius: var(--r); padding: 10px 12px; }
.key span { display: block; font-size: 12.5px; margin: 0; }
.out { margin-top: 18px; border-top: 1px solid var(--line); padding-top: 12px; }
footer { display: flex; justify-content: center; }
footer select { font: inherit; font-size: 13px; color: var(--dim); background: transparent; border: 0; }