:root {
  --bg: #f8fafc;
  --surface: #ffffff;
  --surface-alt: #e8eef7;
  --text: #0f172a;
  --muted: #475569;
  --line: #d7e1ee;
  --primary: #2563eb;
  --primary-dark: #173f96;
  --secondary: #7c3aed;
  --accent: #06b6d4;
  --success: #16a34a;
  --warning: #f59e0b;
  --danger: #dc2626;
  --sidebar: #0f172a;
  --radius: 18px;
  --shadow: 0 24px 60px rgba(15, 23, 42, 0.10);
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color: var(--text);
  background: radial-gradient(circle at top left, #eff6ff, #f8fafc 55%, #eef2ff);
}
a { color: inherit; text-decoration: none; }
p { color: var(--muted); line-height: 1.6; }
h1, h2, h3 { margin: 0 0 12px; }
.button {
  border: 0;
  border-radius: 999px;
  padding: 12px 18px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-weight: 600;
}
.button.primary { background: var(--primary); color: #fff; }
.button.secondary { background: rgba(37, 99, 235, 0.12); color: var(--primary-dark); }
.button.ghost { background: transparent; border: 1px solid var(--line); }
.public-header, .dashboard-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
}
.public-header {
  padding: 26px 38px;
}
.public-main { padding: 0 38px 38px; }
.brand-block, .brand-panel { display: flex; flex-direction: column; gap: 4px; }
.brand-link, .brand-mark { display: inline-flex; align-items: center; }
.brand-logo { display: block; height: 42px; width: auto; max-width: 240px; }
.brand-logo.inverse { height: 40px; }
.brand-title { font-size: 1.35rem; font-weight: 800; }
.brand-subtitle, .eyebrow { color: var(--muted); font-size: 0.92rem; }
.top-nav, .button-row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.hero-grid, .cards-grid {
  display: grid;
  gap: 20px;
  margin-bottom: 24px;
}
.hero-grid { grid-template-columns: 1.7fr 1fr; }
.two-columns { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.three-columns { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.four-columns { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.card {
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid rgba(215, 225, 238, 0.7);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
}
.feature-card.large-card { padding: 32px; }
.stat-card strong { font-size: 2rem; display: block; margin-top: 6px; }
.pricing-card .price { font-size: 2.25rem; font-weight: 800; color: var(--primary-dark); }
.clean-list, .data-list, .timeline-list { margin: 0; padding-left: 18px; }
.data-list li, .timeline-list li { margin-bottom: 10px; }
.dashboard-shell { display: grid; grid-template-columns: 290px minmax(0, 1fr); min-height: 100vh; }
.sidebar {
  background: linear-gradient(180deg, #0f172a, #13223b 60%, #0f172a);
  color: #e2e8f0;
  padding: 28px 20px;
}
.brand-panel { gap: 10px; }
.brand-panel .brand-subtitle { padding-left: 2px; }
.sidebar-nav { display: flex; flex-direction: column; gap: 6px; margin-top: 20px; }
.sidebar-nav a {
  padding: 12px 14px;
  border-radius: 14px;
  color: #cbd5e1;
}
.sidebar-nav a:hover { background: rgba(255,255,255,0.08); color: #fff; }
.app-body { padding: 24px; }
.dashboard-header { padding: 6px 4px 24px; }
.dashboard-content { display: flex; flex-direction: column; gap: 24px; }
.user-chip {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 10px 14px;
}
.section-header { display: flex; justify-content: space-between; align-items: center; gap: 20px; margin-bottom: 18px; }
.stack-form { display: grid; gap: 14px; }
label { display: grid; gap: 8px; font-weight: 600; }
input, textarea, select {
  width: 100%;
  border-radius: 14px;
  border: 1px solid var(--line);
  padding: 12px 14px;
  font: inherit;
  background: #fff;
}
textarea { min-height: 110px; resize: vertical; }
.data-table { width: 100%; border-collapse: collapse; }
.data-table th, .data-table td { padding: 14px 12px; border-bottom: 1px solid var(--line); text-align: left; }
.progress-bar { height: 14px; background: #dbe7f7; border-radius: 999px; overflow: hidden; }
.progress-bar span { display: block; height: 100%; background: linear-gradient(90deg, var(--primary), var(--secondary)); border-radius: 999px; }
.chat-layout { display: grid; grid-template-columns: 320px minmax(0, 1fr); gap: 20px; }
.chat-thread { display: flex; flex-direction: column; gap: 14px; min-height: 420px; max-height: 520px; overflow: auto; margin-bottom: 18px; }
.message { max-width: 78%; padding: 14px 16px; border-radius: 18px; }
.ai-message { background: #fff; border: 1px solid var(--line); align-self: flex-start; }
.user-message { background: linear-gradient(135deg, #dbeafe, #e9d5ff); align-self: flex-end; }
.chat-composer { display: grid; gap: 14px; }
.stretch-row { justify-content: space-between; }
.warning-list strong { color: var(--danger); }
.auth-wrapper { max-width: 520px; margin: 40px auto; }
@media (max-width: 1100px) {
  .hero-grid, .two-columns, .three-columns, .four-columns, .chat-layout, .dashboard-shell { grid-template-columns: 1fr; }
  .sidebar { position: static; }
}