* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", sans-serif;
  background: #0d1117;
  color: #c9d1d9;
  line-height: 1.6;
}

.topbar {
  padding: 24px 16px 16px;
  text-align: center;
  background: linear-gradient(135deg, #161b22 0%, #0d1117 100%);
  border-bottom: 1px solid #30363d;
}

.topbar h1 { margin: 0; font-size: 1.5rem; font-weight: 600; }
.topbar .sub { margin: 4px 0 0; font-size: 0.85rem; color: #8b949e; }

main { max-width: 720px; margin: 0 auto; padding: 16px; }

.panel, .about {
  background: #161b22;
  border: 1px solid #30363d;
  border-radius: 8px;
  padding: 16px;
  margin-bottom: 16px;
}

.pickers { display: flex; gap: 16px; flex-wrap: wrap; }
.picker { flex: 1; min-width: 220px; display: flex; flex-direction: column; gap: 6px; }
.picker label { font-size: 0.8rem; color: #8b949e; }
.row { display: flex; gap: 8px; align-items: center; }
.row input[type="color"] {
  width: 44px; height: 40px; padding: 0; border: 1px solid #30363d;
  border-radius: 6px; background: #0d1117; cursor: pointer;
}
.row input[type="text"] {
  flex: 1; background: #0d1117; border: 1px solid #30363d; color: #c9d1d9;
  border-radius: 6px; padding: 10px 12px;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 1rem;
}

.error {
  margin-top: 10px; color: #ff7b72; background: #3d1418;
  border: 1px solid #f85149; border-radius: 6px; padding: 8px 12px; font-size: 0.85rem;
}

.result {
  display: flex; gap: 16px; margin-bottom: 16px; flex-wrap: wrap;
}
.preview {
  flex: 1; min-width: 260px; border-radius: 8px; border: 1px solid #30363d;
  padding: 24px; display: flex; flex-direction: column; gap: 10px;
  align-items: center; justify-content: center; text-align: center;
}
.preview .big { font-size: 2rem; font-weight: 700; }
.preview .small { font-size: 0.95rem; }

.ratio-box {
  flex: 0 0 180px; background: #161b22; border: 1px solid #30363d; border-radius: 8px;
  padding: 20px; display: flex; flex-direction: column; align-items: center; justify-content: center;
}
.ratio { font-size: 2.6rem; font-weight: 700; font-family: ui-monospace, monospace; color: #ffd33d; }
.ratio-label { font-size: 0.8rem; color: #8b949e; }

.about h2, .panel h2 { margin-top: 0; font-size: 1.05rem; }

.levels { width: 100%; border-collapse: collapse; font-size: 0.9rem; }
.levels th { text-align: left; padding: 6px 8px; color: #8b949e; border-bottom: 1px solid #30363d; }
.levels td { padding: 7px 8px; border-bottom: 1px solid #1c2331; }
.levels .req { font-family: ui-monospace, monospace; color: #8b949e; }
.badge { font-weight: 600; font-size: 0.85rem; padding: 2px 10px; border-radius: 12px; }
.badge.pass { background: #12351f; color: #3fb950; }
.badge.fail { background: #3d1418; color: #f85149; }

.about p, .about ol { font-size: 0.9rem; }
.about li { margin-bottom: 3px; }
.about code { font-family: ui-monospace, monospace; font-size: 0.82em; background: #21262d; padding: 1px 5px; border-radius: 3px; }
.dim { color: #8b949e; font-size: 0.85rem; }
.about a { color: #58a6ff; }

footer {
  border-top: 1px solid #30363d; padding: 16px; text-align: center;
  font-size: 0.85rem; color: #8b949e; display: flex; justify-content: space-between;
  flex-wrap: wrap; gap: 8px; max-width: 720px; margin: 24px auto 0;
}
footer a { color: #58a6ff; }