:root {
  --bg: #f7fbff;
  --bg-elev: #ffffff;
  --text: #0f172a;
  --muted: #475569;
  --primary: #2563eb; /* blue-600 */
  --primary-ghost: #dbeafe; /* blue-100 */
  --accent: #60a5fa; /* blue-400 */
  --ring: rgba(37, 99, 235, 0.35);
  --radius: 14px;
  --shadow-soft: 16px 16px 40px rgba(9, 30, 66, 0.08), -16px -16px 40px rgba(255, 255, 255, 0.8);
  --shadow-card: 10px 10px 24px rgba(9, 30, 66, 0.12), -8px -8px 24px rgba(255, 255, 255, 0.9);
}

* { box-sizing: border-box; }
html, body { height: 100%; }

body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif;
  background: var(--bg);
  color: var(--text);
}

.sb-header, .sb-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 24px;
  background: var(--bg);
  backdrop-filter: saturate(120%) blur(6px);
  position: sticky;
  top: 0;
  z-index: 10;
}

.brand {
  font-weight: 800;
  letter-spacing: 0.2px;
  color: var(--primary);
}

.sb-nav a {
  margin: 0 10px;
  text-decoration: none;
  color: var(--muted);
  padding: 8px 12px;
  border-radius: 10px;
}
.sb-nav a:hover {
  color: var(--primary);
  background: var(--primary-ghost);
}

.container {
  padding: 24px;
  max-width: 1100px;
  margin: 0 auto;
}

.hero {
  padding: 32px;
  border-radius: var(--radius);
  background: var(--bg-elev);
}
.hero h1 { margin: 0 0 8px; }
.hero-actions .btn { margin-right: 12px; }

.cards {
  margin-top: 24px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}

.card {
  padding: 20px;
  border-radius: var(--radius);
  background: var(--bg-elev);
}

.card-3d {
  box-shadow: var(--shadow-card);
}

.btn {
  display: inline-block;
  padding: 10px 16px;
  border-radius: 12px;
  border: 1px solid transparent;
  text-decoration: none;
  cursor: pointer;
}
.btn-primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 10px 22px var(--ring);
}
.btn-primary:hover { filter: brightness(1.05); }
.btn-secondary {
  background: var(--bg-elev);
  color: var(--primary);
  border: 1px solid var(--primary);
}
.btn-link {
  color: var(--primary);
  text-decoration: underline;
}

.input, input, select, textarea {
  width: 100%;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid #e2e8f0;
  background: var(--bg-elev);
  outline: none;
}
.input:focus, input:focus { border-color: var(--primary); box-shadow: 0 0 0 4px var(--ring); }

.row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.row-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }

.list {
  display: grid; gap: 10px;
}
.list-item {
  padding: 14px;
  border-radius: 12px;
  background: var(--bg-elev);
  box-shadow: var(--shadow-soft);
  display: flex; align-items: center; justify-content: space-between;
}

.kbd {
  background: #e2e8f0;
  border-radius: 6px;
  padding: 2px 6px;
  font-size: 12px;
  color: #334155;
}

.sb-footer {
  position: static;
  margin-top: 40px;
  color: var(--muted);
}

/* Modal */
.modal-backdrop {
  position: fixed; inset: 0; background: rgba(15, 23, 42, 0.25);
  display: none; align-items: center; justify-content: center;
}
.modal {
  width: 560px; max-width: 92%;
  background: var(--bg-elev);
  border-radius: 16px; padding: 20px;
  box-shadow: var(--shadow-card);
}
.modal-actions { display: flex; justify-content: flex-end; gap: 8px; margin-top: 12px; }
.modal-backdrop.show { display: flex; }

/* Tag */
.tag {
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--primary-ghost); color: var(--primary);
  padding: 6px 10px; border-radius: 999px; font-size: 12px;
}