/* OmniPrompt Landing — vanilla CSS, no framework
 * Design goals:
 *  - Minimal CSS payload (<10KB) for fast first paint
 *  - System font stack (no web font requests)
 *  - Responsive single-stylesheet layout
 *  - Dark/light mode via prefers-color-scheme
 */

:root {
  --bg: #0b1020;
  --bg-elev: #121830;
  --bg-alt: #0f1428;
  --fg: #e7ecf7;
  --fg-muted: #a4afc7;
  --fg-soft: #7d8aa6;
  --border: #1f2747;
  --accent: #6b8cff;
  --accent-strong: #4b6cff;
  --accent-fg: #ffffff;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
  --radius: 12px;
  --radius-lg: 18px;
  --max-width: 1100px;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f7f9ff;
    --bg-elev: #ffffff;
    --bg-alt: #eff3ff;
    --fg: #131a30;
    --fg-muted: #4a5572;
    --fg-soft: #6b7693;
    --border: #dde3f3;
    --accent: #3057ff;
    --accent-strong: #1f3edd;
    --accent-fg: #ffffff;
    --shadow: 0 8px 24px rgba(48, 87, 255, 0.12);
  }
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue",
    Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--fg);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover,
a:focus-visible {
  text-decoration: underline;
}

img,
svg {
  max-width: 100%;
  display: block;
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in oklab, var(--bg) 85%, transparent);
  backdrop-filter: saturate(140%) blur(8px);
  -webkit-backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--fg);
  font-weight: 700;
  letter-spacing: 0.2px;
  text-decoration: none;
}

.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: var(--accent-fg);
  font-size: 16px;
}

.primary-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.primary-nav a {
  color: var(--fg-muted);
  font-size: 14px;
}

.primary-nav a:hover {
  color: var(--fg);
  text-decoration: none;
}

.nav-cta {
  background: var(--accent);
  color: var(--accent-fg) !important;
  padding: 8px 14px;
  border-radius: 999px;
  font-weight: 600;
}

.nav-cta:hover {
  background: var(--accent-strong);
  text-decoration: none !important;
}

@media (max-width: 640px) {
  .primary-nav {
    gap: 14px;
  }
  .primary-nav a:not(.nav-cta) {
    display: none;
  }
}

/* Hero */
.hero {
  padding: 96px 0 64px;
  background:
    radial-gradient(circle at 10% -20%, color-mix(in oklab, var(--accent) 24%, transparent), transparent 60%),
    radial-gradient(circle at 90% 0%, color-mix(in oklab, var(--accent-strong) 18%, transparent), transparent 55%);
}

.hero-inner {
  max-width: 820px;
  text-align: center;
}

.eyebrow {
  display: inline-block;
  margin: 0 0 16px;
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 12px;
  letter-spacing: 0.6px;
  text-transform: uppercase;
  color: var(--fg-muted);
  background: var(--bg-elev);
}

h1 {
  font-size: clamp(36px, 5.6vw, 56px);
  line-height: 1.1;
  margin: 0 0 20px;
  letter-spacing: -0.02em;
}

.lede {
  font-size: clamp(16px, 1.8vw, 19px);
  color: var(--fg-muted);
  margin: 0 auto 28px;
  max-width: 640px;
}

.cta-row {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 15px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.05s ease, background 0.15s ease, border-color 0.15s ease;
}

.btn-primary {
  background: var(--accent);
  color: var(--accent-fg);
}

.btn-primary:hover {
  background: var(--accent-strong);
  text-decoration: none;
}

.btn-ghost {
  background: transparent;
  color: var(--fg);
  border-color: var(--border);
}

.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
  text-decoration: none;
}

.btn:active {
  transform: translateY(1px);
}

.btn-block {
  display: block;
  width: 100%;
  margin-top: 20px;
}

.hero-meta {
  list-style: none;
  padding: 0;
  margin: 32px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 22px;
  justify-content: center;
  color: var(--fg-soft);
  font-size: 13px;
}

.hero-meta li::before {
  content: "•";
  margin-right: 10px;
  color: var(--accent);
}

.hero-meta li:first-child::before {
  display: none;
}

/* Section base */
.section {
  padding: 80px 0;
  border-top: 1px solid var(--border);
}

.section-alt {
  background: var(--bg-alt);
}

.section h2 {
  font-size: clamp(28px, 3.6vw, 36px);
  margin: 0 0 12px;
  letter-spacing: -0.01em;
}

.section-lede {
  color: var(--fg-muted);
  margin: 0 0 36px;
  max-width: 640px;
}

.grid {
  display: grid;
  gap: 18px;
}

/* Features */
.features {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 22px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.card:hover {
  border-color: color-mix(in oklab, var(--accent) 50%, var(--border));
  transform: translateY(-2px);
}

.card h3 {
  margin: 0 0 8px;
  font-size: 18px;
}

.card p {
  margin: 0;
  color: var(--fg-muted);
  font-size: 14.5px;
}

/* Pricing */
.pricing {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  max-width: 760px;
  margin: 0 auto;
}

.plan {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
}

.plan-featured {
  border-color: var(--accent);
  box-shadow: var(--shadow);
  position: relative;
}

.plan-head h3 {
  margin: 0 0 6px;
  font-size: 18px;
  color: var(--fg-muted);
  font-weight: 600;
}

.price {
  display: flex;
  align-items: baseline;
  gap: 6px;
  margin: 0 0 4px;
}

.amount {
  font-size: 38px;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.period {
  color: var(--fg-soft);
  font-size: 14px;
}

.badge {
  display: inline-block;
  margin-top: 6px;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 11px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  background: color-mix(in oklab, var(--accent) 15%, transparent);
  color: var(--accent);
}

.plan-features {
  list-style: none;
  padding: 0;
  margin: 18px 0 0;
}

.plan-features li {
  padding: 8px 0 8px 26px;
  position: relative;
  color: var(--fg-muted);
  font-size: 14.5px;
  border-bottom: 1px solid var(--border);
}

.plan-features li:last-child {
  border-bottom: none;
}

.plan-features li::before {
  content: "✓";
  position: absolute;
  left: 0;
  top: 8px;
  color: var(--accent);
  font-weight: 700;
}

/* Downloads */
.downloads {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.download-card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 22px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  color: var(--fg);
  text-decoration: none;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.download-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  text-decoration: none;
}

.dl-icon {
  font-size: 26px;
  line-height: 1;
}

.dl-title {
  font-weight: 700;
  font-size: 18px;
}

.dl-meta {
  color: var(--fg-soft);
  font-size: 13px;
}

.download-note {
  margin-top: 24px;
  color: var(--fg-soft);
  font-size: 14px;
}

/* FAQ */
.faq {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

details {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 18px;
}

details + details {
  margin-top: 0;
}

details[open] {
  border-color: color-mix(in oklab, var(--accent) 40%, var(--border));
}

summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
}

summary::-webkit-details-marker {
  display: none;
}

summary::after {
  content: "+";
  color: var(--accent);
  font-weight: 700;
  transition: transform 0.2s ease;
}

details[open] summary::after {
  content: "−";
}

details p {
  margin: 10px 0 0;
  color: var(--fg-muted);
  font-size: 14.5px;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg-alt);
  padding: 36px 0;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 16px;
  align-items: center;
  text-align: center;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  color: var(--fg);
}

.footer-nav {
  display: flex;
  gap: 22px;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-nav a {
  color: var(--fg-muted);
  font-size: 14px;
}

.footer-meta {
  margin: 0;
  color: var(--fg-soft);
  font-size: 13px;
}

@media (min-width: 720px) {
  .footer-inner {
    flex-direction: row;
    justify-content: space-between;
    text-align: left;
  }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .card,
  .download-card,
  .btn {
    transition: none;
  }
}