:root {
  --brand: #4f46e5;
  --brand-d: #4338ca;
  --purple: #7c3aed;
  --fg: #1b1f2e;
  --muted: #5b6478;
  --line: #e7e9f0;
  --chip: #eef2ff;
  --bg: #ffffff;
  --soft: #f7f8fc;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--fg);
  background: var(--bg);
}
a { color: var(--brand-d); }
.wrap { max-width: 960px; margin: 0 auto; padding: 0 20px; }
header.site {
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 20px; max-width: 960px; margin: 0 auto;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; text-decoration: none; color: var(--fg); }
.brand .logo { display: inline-grid; place-items: center; width: 28px; height: 28px; background: var(--brand); color: #fff; border-radius: 7px; font-size: 16px; }
nav a { margin-left: 18px; text-decoration: none; color: var(--muted); font-size: 15px; }
nav a:hover { color: var(--brand-d); }

.hero { text-align: center; padding: 64px 20px 36px; background: linear-gradient(160deg, #eef2ff, #faf9ff); }
.hero h1 { font-size: 42px; line-height: 1.15; margin: 0 0 16px; letter-spacing: -0.5px; }
.hero p.lead { font-size: 20px; color: var(--muted); max-width: 660px; margin: 0 auto 28px; }
.cta { display: inline-flex; gap: 12px; flex-wrap: wrap; justify-content: center; }
.btn { display: inline-block; padding: 13px 24px; border-radius: 10px; font-weight: 650; text-decoration: none; font-size: 16px; border: 1px solid transparent; }
.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:hover { background: var(--brand-d); }
.btn-ghost { background: #fff; color: var(--brand-d); border-color: var(--line); }
.btn-ghost:hover { border-color: #c7cbf5; }
.note { color: var(--muted); font-size: 14px; margin-top: 14px; }

section { padding: 44px 0; }
h2 { font-size: 28px; letter-spacing: -0.3px; margin: 0 0 8px; }
.section-sub { color: var(--muted); margin: 0 0 28px; }
.features { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
.feature { border: 1px solid var(--line); border-radius: 14px; padding: 20px; background: var(--soft); }
.feature h3 { margin: 0 0 6px; font-size: 17px; }
.feature p { margin: 0; color: var(--muted); font-size: 15px; }

/* tool */
.tool { display: grid; gap: 16px; }
textarea#html-in {
  width: 100%; min-height: 160px; padding: 14px; border: 1px solid var(--line);
  border-radius: 12px; font: 13px/1.5 ui-monospace, Menlo, Consolas, monospace; resize: vertical;
}
.toolbar { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
button.act {
  border: 1px solid var(--line); background: #fff; color: var(--fg); border-radius: 9px;
  padding: 10px 16px; font-weight: 600; cursor: pointer; font-size: 14px;
}
button.act.primary { background: var(--brand); color: #fff; border-color: var(--brand); }
button.act:hover { border-color: #c7cbf5; }
button.act:disabled { opacity: .5; cursor: default; }
#result { min-height: 24px; color: var(--muted); font-size: 14px; }
table.preview { border-collapse: collapse; width: 100%; font-size: 13px; overflow: auto; display: block; max-height: 360px; }
table.preview th, table.preview td { border: 1px solid var(--line); padding: 6px 10px; white-space: nowrap; text-align: left; }
table.preview tr:first-child td, table.preview thead th { background: var(--chip); font-weight: 650; }
.tablepick { display: flex; gap: 8px; flex-wrap: wrap; }
.tablepick button { border: 1px solid var(--line); background: #fff; border-radius: 999px; padding: 6px 12px; font-size: 13px; cursor: pointer; }
.tablepick button.sel { background: var(--brand); color: #fff; border-color: var(--brand); }

.faq { border-top: 1px solid var(--line); padding-top: 8px; }
.faq details { border-bottom: 1px solid var(--line); padding: 14px 0; }
.faq summary { font-weight: 650; cursor: pointer; }
.faq p { color: var(--muted); margin: 10px 0 0; }

.callout { background: var(--chip); border: 1px solid #dfe3fb; border-radius: 14px; padding: 20px 22px; }
.callout h3 { margin: 0 0 6px; }

footer.site { border-top: 1px solid var(--line); padding: 28px 20px; color: var(--muted); font-size: 14px; }
footer.site .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; }
footer.site a { color: var(--muted); text-decoration: none; margin-left: 16px; }
footer.site a:hover { color: var(--brand-d); }

@media (max-width: 680px) {
  .hero h1 { font-size: 32px; }
  .features { grid-template-columns: 1fr; }
}