:root {
  --bg: #f4f7fb;
  --card: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;
  --line: #d1d5db;
  --brand: #0f766e;
  --brand-soft: #ccfbf1;
  --danger: #b91c1c;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at 10% 10%, #ecfeff, transparent 35%),
              radial-gradient(circle at 90% 0%, #e0e7ff, transparent 40%),
              var(--bg);
  min-height: 100vh;
}

a { color: inherit; text-decoration: none; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid #e5e7eb;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(6px);
}

.header-inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: 10px 14px;
  display: flex;
  gap: 10px;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
}

.brand {
  font-weight: 700;
  color: #115e59;
}

.nav {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.nav a {
  border: 1px solid #dbe5ef;
  background: #fff;
  border-radius: 999px;
  padding: 6px 10px;
  font-size: 13px;
}

.nav a.active {
  border-color: #99f6e4;
  background: #ecfeff;
  color: #115e59;
}

.wrap {
  max-width: 1080px;
  margin: 0 auto;
  padding: 18px 14px 40px;
}

h1 { margin: 8px 0; font-size: 30px; line-height: 1.2; }
h2 { margin: 0 0 10px; font-size: 22px; }
h3 { margin: 0 0 8px; font-size: 17px; }

.sub { margin: 0 0 16px; color: var(--muted); font-size: 14px; }

.grid {
  display: grid;
  gap: 14px;
  grid-template-columns: 1fr;
}

.card {
  background: var(--card);
  border: 1px solid #e5e7eb;
  border-radius: 12px;
  padding: 14px;
  box-shadow: 0 2px 10px rgba(15, 23, 42, 0.04);
}

.row {
  display: grid;
  gap: 10px;
  grid-template-columns: repeat(12, 1fr);
  margin-bottom: 10px;
}

.field { grid-column: span 12; }
.field.sm6 { grid-column: span 6; }
.field.sm4 { grid-column: span 4; }
.field.sm3 { grid-column: span 3; }
.field.sm2 { grid-column: span 2; }
.field.sm8 { grid-column: span 8; }

label {
  display: block;
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 4px;
}

input, select, button, textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px;
  font-size: 14px;
  background: #fff;
  color: var(--text);
}

input:focus, select:focus, textarea:focus {
  outline: 2px solid #99f6e4;
  border-color: var(--brand);
}

button { cursor: pointer; font-weight: 600; }

.btn-primary { background: var(--brand); color: #fff; border-color: var(--brand); }
.btn-soft { background: var(--brand-soft); border-color: #99f6e4; color: #115e59; }
.btn-danger { background: #fee2e2; color: var(--danger); border-color: #fecaca; }

.muted { color: var(--muted); font-size: 13px; }
.warn { color: var(--danger); }

.result-box {
  border: 1px dashed #a7f3d0;
  border-radius: 10px;
  background: #f0fdfa;
  padding: 10px;
  margin-top: 8px;
  font-size: 14px;
  line-height: 1.7;
}

.tool-link {
  display: block;
  border: 1px solid #e5e7eb;
  border-radius: 10px;
  padding: 12px;
  background: #fff;
}

.tool-link strong { color: #0f766e; }

.list { display: grid; gap: 10px; }

.tag {
  display: inline-block;
  border: 1px solid #bfdbfe;
  background: #eff6ff;
  color: #1d4ed8;
  border-radius: 999px;
  font-size: 12px;
  padding: 2px 8px;
  margin-right: 6px;
}

footer {
  margin-top: 18px;
  font-size: 12px;
  color: #4b5563;
  background: #fffbeb;
  border: 1px solid #fde68a;
  border-radius: 10px;
  padding: 10px;
}

.modal {
  position: fixed;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 14px;
  background: rgba(15, 23, 42, 0.42);
  z-index: 30;
}

.modal.show { display: flex; }

.modal-panel {
  width: min(780px, 100%);
  max-height: 90vh;
  overflow: auto;
  background: #fff;
  border-radius: 12px;
  border: 1px solid #e5e7eb;
  box-shadow: 0 14px 36px rgba(15, 23, 42, 0.2);
  padding: 14px;
}

textarea {
  min-height: 180px;
  resize: vertical;
  font-family: Consolas, "Courier New", monospace;
  font-size: 13px;
}

@media (min-width: 800px) {
  .grid.two { grid-template-columns: 1fr 1fr; }
  .grid.three { grid-template-columns: repeat(3, 1fr); }
}