:root {
  --bg: #0b1220;
  --surface: #111827;
  --surface-alt: rgba(17, 24, 39, 0.8);
  --text: #e5e7eb;
  --muted: #9ca3af;
  --primary: #3b82f6;
  --accent: #f59e0b;
  --success: #10b981;
  --danger: #ef4444;
  --card-border: rgba(255, 255, 255, 0.06);
  --shadow-soft: 0 12px 32px rgba(8, 15, 35, 0.45);
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --space-2xs: 0.5rem;
  --space-xs: 0.75rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --space-2xl: 4rem;
  --transition: 200ms ease;
  --max-width: 72.5rem;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  height: 100%;
}

body {
  background: radial-gradient(circle at top left, #172033, var(--bg) 45%);
  color: var(--text);
  font-size: 1rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

::selection {
  background-color: rgba(59, 130, 246, 0.35);
  color: var(--text);
}

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

button,
input,
select {
  font: inherit;
  color: inherit;
}

a {
  color: inherit;
  text-decoration: none;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.container {
  width: min(100% - 2rem, var(--max-width));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: linear-gradient(180deg, rgba(11, 18, 32, 0.9), rgba(11, 18, 32, 0.65));
  backdrop-filter: blur(0);
  transition: background var(--transition), backdrop-filter var(--transition), border var(--transition);
  border-bottom: 1px solid transparent;
}

.site-header.is-scrolled {
  background: rgba(11, 18, 32, 0.85);
  backdrop-filter: blur(12px);
  border-bottom-color: rgba(255, 255, 255, 0.05);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-sm);
  padding-block: var(--space-sm);
}

.nav__logo {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
}

.nav__mark {
  width: 2rem;
  height: 2rem;
  fill: var(--primary);
  stroke: none;
}

.nav__wordmark {
  font-weight: 600;
  letter-spacing: 0.01em;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.nav__links a {
  padding: 0.35rem 0.5rem;
  border-radius: var(--radius-sm);
  transition: color var(--transition), background var(--transition);
}

.nav__links a:hover,
.nav__links a:focus-visible {
  color: var(--primary);
  background: rgba(59, 130, 246, 0.15);
}

.nav__links .is-muted {
  color: var(--muted);
}

.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 0.35rem;
  background: none;
  border: none;
  padding: 0.5rem;
  border-radius: var(--radius-sm);
}

.nav__toggle-bar {
  width: 1.5rem;
  height: 2px;
  background: var(--text);
  border-radius: 999px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  padding: 0.75rem 1.5rem;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform var(--transition), background var(--transition), border var(--transition), color var(--transition);
}

.button--primary {
  background: linear-gradient(135deg, var(--primary), #2563eb);
  color: #fff;
  box-shadow: 0 10px 30px rgba(59, 130, 246, 0.35);
}

.button--primary:hover,
.button--primary:focus-visible {
  transform: translateY(-1px);
  box-shadow: 0 16px 36px rgba(59, 130, 246, 0.45);
}

.button--ghost {
  background: transparent;
  border-color: rgba(229, 231, 235, 0.2);
}

.button--ghost:hover,
.button--ghost:focus-visible {
  background: rgba(229, 231, 235, 0.08);
  border-color: rgba(229, 231, 235, 0.4);
}

.hero {
  padding-block: var(--space-2xl);
  position: relative;
}

.hero__grid {
  display: grid;
  gap: var(--space-xl);
  align-items: center;
}

.hero__content h1 {
  font-size: clamp(2.5rem, 4vw, 3.75rem);
  line-height: 1.1;
  margin-bottom: var(--space-sm);
}

.hero__content p {
  max-width: 36rem;
  color: rgba(229, 231, 235, 0.85);
}

.eyebrow {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--accent);
  margin-bottom: var(--space-xs);
}

.idea-form {
  margin-block: var(--space-md);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  background: rgba(17, 24, 39, 0.9);
  padding: var(--space-xs);
  border-radius: var(--radius-lg);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.05);
}

.idea-form input {
  flex: 1;
  min-width: 230px;
  background: rgba(15, 23, 42, 0.75);
  border: 1px solid rgba(148, 163, 184, 0.3);
  border-radius: var(--radius-md);
  padding: 0.85rem 1rem;
  color: var(--text);
}

.idea-form input:focus-visible {
  border-color: var(--primary);
  outline: none;
}

.hero__badges {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
}

.badge {
  padding: 0.35rem 0.9rem;
  border-radius: 999px;
  background: rgba(148, 163, 184, 0.18);
  color: rgba(229, 231, 235, 0.8);
  font-size: 0.85rem;
}

.hero__trust {
  margin-top: var(--space-lg);
}

.hero__trust-text {
  color: var(--muted);
  font-size: 0.95rem;
  margin-bottom: var(--space-xs);
}

.hero__logos {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(110px, 1fr));
  gap: var(--space-xs);
}

.logo-placeholder {
  display: grid;
  place-items: center;
  padding: var(--space-xs);
  border-radius: var(--radius-md);
  background: rgba(15, 23, 42, 0.7);
  color: var(--muted);
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.hero__mock {
  display: grid;
  gap: var(--space-sm);
}

.mock-card {
  background: rgba(17, 24, 39, 0.92);
  border-radius: var(--radius-lg);
  padding: var(--space-md);
  border: 1px solid var(--card-border);
  box-shadow: var(--shadow-soft);
}

.mock-card__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-sm);
}

.mock-card__title {
  font-weight: 600;
  font-size: 1rem;
}

.mock-card__chip {
  padding: 0.3rem 0.7rem;
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
  border-radius: 999px;
  font-size: 0.75rem;
}

.mock-card__list {
  list-style: disc;
  margin-left: 1.1rem;
  color: rgba(229, 231, 235, 0.8);
  padding-left: 0.75rem;
}

.mock-card__list--ideas {
  list-style: none;
  padding-left: 0;
}

.mock-card__list--ideas li::before {
  content: '→';
  color: var(--accent);
  margin-right: 0.6rem;
}

.mock-card--confidence {
  display: grid;
  gap: var(--space-sm);
}

.mock-card__value {
  font-size: 1.35rem;
  font-weight: 600;
}

.mock-card__gauge {
  width: 120px;
  margin-inline: auto;
}

.mock-card__gauge svg {
  width: 100%;
  height: auto;
}

.gauge-bg {
  fill: none;
  stroke: rgba(148, 163, 184, 0.2);
  stroke-width: 12;
}

.gauge-progress {
  fill: none;
  stroke: var(--success);
  stroke-width: 12;
  stroke-linecap: round;
  transform: rotate(-90deg);
  transform-origin: 50% 50%;
}

.analysis-panel {
  margin-top: var(--space-xl);
}

.analysis {
  background: rgba(17, 24, 39, 0.9);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: var(--shadow-soft);
}

.analysis__header {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.analysis__confidence {
  padding: 0.4rem 0.85rem;
  border-radius: 999px;
  background: rgba(245, 158, 11, 0.1);
  color: var(--accent);
  font-weight: 600;
}

.analysis__confidence[data-level='high'] {
  background: rgba(16, 185, 129, 0.12);
  color: var(--success);
}

.analysis__confidence[data-level='medium'] {
  background: rgba(245, 158, 11, 0.12);
  color: var(--accent);
}

.analysis__confidence[data-level='low'] {
  background: rgba(239, 68, 68, 0.12);
  color: var(--danger);
}

.analysis__content {
  display: grid;
  gap: var(--space-lg);
}

.analysis__sources,
.analysis__ideas {
  background: rgba(15, 23, 42, 0.6);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  border: 1px solid rgba(148, 163, 184, 0.15);
}

.analysis__list {
  margin: 0;
  padding-left: 1.2rem;
  list-style: disc;
}

.analysis__list li {
  margin-bottom: 0.5rem;
}

.tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: var(--space-sm);
  flex-wrap: wrap;
}

.tabs__button {
  padding: 0.5rem 1rem;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(148, 163, 184, 0.3);
  background: transparent;
  cursor: pointer;
  color: var(--muted);
  transition: background var(--transition), color var(--transition), border var(--transition);
}

.tabs__button.is-active,
.tabs__button:hover,
.tabs__button:focus-visible {
  color: var(--text);
  background: rgba(59, 130, 246, 0.18);
  border-color: rgba(59, 130, 246, 0.45);
}

.tabs__panel {
  display: none;
}

.tabs__panel.is-active {
  display: block;
}

.section {
  padding-block: var(--space-2xl);
}

.section--alt {
  background: rgba(10, 16, 30, 0.6);
}

.section__header {
  text-align: center;
  max-width: 40rem;
  margin: 0 auto var(--space-xl);
}

.section__header p {
  color: rgba(229, 231, 235, 0.75);
}

.benefits-grid,
.feature-cards,
.pricing-grid {
  display: grid;
  gap: var(--space-md);
}

.card {
  background: rgba(17, 24, 39, 0.85);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  transition: transform var(--transition), border var(--transition), box-shadow var(--transition);
}

.card:hover,
.card:focus-within {
  transform: translateY(-4px);
  border-color: rgba(59, 130, 246, 0.35);
  box-shadow: var(--shadow-soft);
}

.card__icon {
  width: 2.5rem;
  height: 2.5rem;
  display: grid;
  place-items: center;
  border-radius: var(--radius-sm);
  background: rgba(59, 130, 246, 0.12);
  margin-bottom: var(--space-sm);
}

.card__icon svg {
  width: 1.5rem;
  height: 1.5rem;
  fill: var(--primary);
}

.steps {
  display: grid;
  gap: var(--space-md);
}

.demo {
  display: grid;
  gap: var(--space-md);
}

.demo__controls {
  display: grid;
  gap: 0.4rem;
}

.demo__controls label {
  font-weight: 600;
}

.demo__controls select {
  background: rgba(15, 23, 42, 0.7);
  border-radius: var(--radius-md);
  border: 1px solid rgba(148, 163, 184, 0.3);
  padding: 0.65rem 0.85rem;
}

.demo__content {
  display: grid;
  gap: var(--space-md);
}

.demo__panel {
  background: rgba(15, 23, 42, 0.65);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  border: 1px solid rgba(148, 163, 184, 0.15);
}

.demo__list {
  margin: 0;
  padding-left: 1.2rem;
}

.sentiment {
  display: grid;
  gap: 0.75rem;
}

.sentiment__row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.9rem;
}

.sentiment__bar {
  flex: 1;
  height: 0.5rem;
  border-radius: 999px;
  background: rgba(148, 163, 184, 0.2);
  overflow: hidden;
}

.sentiment__fill {
  height: 100%;
  border-radius: inherit;
  background: var(--primary);
}

.confidence-meter {
  font-size: 2rem;
  font-weight: 700;
  color: var(--accent);
}

.feature-cards {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.pricing-toggle {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  background: rgba(17, 24, 39, 0.7);
  padding: 0.5rem;
  border-radius: 999px;
  border: 1px solid rgba(148, 163, 184, 0.2);
  margin: 0 auto var(--space-lg);
}

.toggle {
  background: transparent;
  border-radius: 999px;
  border: none;
  padding: 0.5rem 1rem;
  color: var(--muted);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}

.toggle.is-active {
  background: rgba(59, 130, 246, 0.25);
  color: var(--text);
}

.toggle__save {
  color: var(--accent);
  font-weight: 600;
  margin-left: 0.3rem;
}

.pricing-grid {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.pricing-card__badge {
  background: rgba(245, 158, 11, 0.15);
  color: var(--accent);
  display: inline-block;
  padding: 0.3rem 0.75rem;
  border-radius: 999px;
  font-size: 0.8rem;
  margin-bottom: var(--space-xs);
}

.pricing-card--featured {
  position: relative;
  border-color: rgba(59, 130, 246, 0.45);
  box-shadow: 0 20px 40px rgba(37, 99, 235, 0.25);
}

.pricing-card__price {
  font-size: 2rem;
  font-weight: 700;
  margin: var(--space-sm) 0;
}

.pricing-card__features {
  list-style: none;
  padding: 0;
  margin: 0 0 var(--space-md);
  display: grid;
  gap: 0.65rem;
}

.pricing-card__features li::before {
  content: '✔';
  color: var(--success);
  margin-right: 0.6rem;
}

.accordion__item {
  border-radius: var(--radius-lg);
  background: rgba(17, 24, 39, 0.8);
  border: 1px solid var(--card-border);
  overflow: hidden;
}

.accordion__item + .accordion__item {
  margin-top: var(--space-sm);
}

.accordion__trigger {
  width: 100%;
  background: none;
  border: none;
  color: inherit;
  text-align: left;
  padding: var(--space-md);
  font-size: 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-sm);
  cursor: pointer;
}

.accordion__trigger svg {
  width: 1.25rem;
  height: 1.25rem;
  stroke: var(--muted);
  stroke-width: 2;
}

.accordion__trigger[aria-expanded='true'] svg {
  transform: rotate(45deg);
  transition: transform var(--transition);
}

.accordion__panel {
  padding: 0 var(--space-md) var(--space-md);
  color: rgba(229, 231, 235, 0.8);
}

.cta {
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.18), rgba(17, 24, 39, 0.9));
}

.cta__content {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  align-items: flex-start;
}

.footer {
  background: rgba(6, 10, 18, 0.95);
  padding: var(--space-xl) 0 var(--space-lg);
  font-size: 0.95rem;
}

.footer__grid {
  display: grid;
  gap: var(--space-lg);
  align-items: start;
}

.footer__links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 0.75rem;
  color: var(--muted);
}

.footer__note {
  color: rgba(148, 163, 184, 0.7);
  margin-top: var(--space-sm);
  max-width: 24rem;
}

.footer__small {
  margin-top: var(--space-lg);
  text-align: center;
  color: rgba(148, 163, 184, 0.6);
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

[hidden] {
  display: none !important;
}

.fade-in {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 600ms ease, transform 600ms ease;
}

.fade-in.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 1024px) {
  .hero__grid {
    grid-template-columns: 1fr;
  }

  .nav__links {
    position: fixed;
    inset: 4.5rem 1rem auto;
    background: rgba(11, 18, 32, 0.95);
    border: 1px solid rgba(59, 130, 246, 0.2);
    border-radius: var(--radius-md);
    flex-direction: column;
    padding: var(--space-md);
    gap: var(--space-sm);
    transform: translateY(-20px);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition), transform var(--transition);
  }

  .nav__links.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav__toggle {
    display: inline-flex;
  }

  .nav__links a {
    width: 100%;
  }

  .site-header {
    padding-inline: 0;
  }
}

@media (min-width: 768px) {
  .hero__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .analysis__content {
    grid-template-columns: 2fr 1fr;
  }

  .benefits-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .steps {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .demo__content {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .cta__content {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }

  .footer__grid {
    grid-template-columns: 1.5fr 1fr;
  }
}

@media (min-width: 1024px) {
  .benefits-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .pricing-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 1ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 1ms !important;
    scroll-behavior: auto !important;
  }

  .fade-in {
    opacity: 1;
    transform: none;
  }
}