:root {
  --bg: #0f1419;
  --card: #1a222c;
  --text: #e8eef4;
  --muted: #8b9aab;
  --accent: #3d8bfd;
  --line: #2a3542;
  --font: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font);
  color: var(--text);
  background:
    radial-gradient(900px 500px at 10% -10%, #1a3a5c 0%, transparent 55%),
    radial-gradient(700px 400px at 100% 0%, #243018 0%, transparent 50%),
    var(--bg);
}

.wrap {
  max-width: 720px;
  margin: 0 auto;
  padding: 48px 20px 80px;
}

.hero { margin-bottom: 28px; }
.brand {
  margin: 0 0 8px;
  letter-spacing: 0.18em;
  font-size: 12px;
  color: var(--accent);
  font-weight: 600;
}
.hero h1 {
  margin: 0 0 10px;
  font-size: 28px;
  font-weight: 650;
}
.sub { margin: 0; color: var(--muted); line-height: 1.55; }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px 22px;
  margin-bottom: 16px;
}
.card h2 {
  margin: 0 0 14px;
  font-size: 16px;
  font-weight: 600;
}

.plans {
  margin: 0;
  padding-left: 1.2em;
  line-height: 1.8;
  color: var(--text);
}
.hint { margin: 14px 0 0; color: var(--muted); font-size: 13px; line-height: 1.5; }

label {
  display: block;
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 12px;
}
input, select {
  display: block;
  width: 100%;
  margin-top: 6px;
  padding: 10px 12px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #121820;
  color: var(--text);
  font-size: 14px;
}
.row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 12px;
}

.btn {
  appearance: none;
  border: none;
  background: var(--accent);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  padding: 10px 16px;
  border-radius: 8px;
  cursor: pointer;
}
.btn:hover { filter: brightness(1.06); }
.btn-ghost {
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
}

.out {
  margin-top: 14px;
  padding: 12px;
  background: #0c1016;
  border-radius: 8px;
  border: 1px solid var(--line);
  font-size: 12px;
  line-height: 1.5;
  overflow: auto;
  max-height: 360px;
  white-space: pre-wrap;
  word-break: break-all;
}

.foot {
  margin-top: 24px;
  color: var(--muted);
  font-size: 13px;
}
.foot a { color: var(--accent); }
code {
  font-size: 12px;
  background: #121820;
  padding: 2px 6px;
  border-radius: 4px;
}