:root {
  --gray-950: oklch(13.5% 0.015 265);
  --gray-900: oklch(21% 0.02 265);
  --gray-800: oklch(28% 0.022 265);
  --gray-700: oklch(37% 0.022 265);
  --gray-600: oklch(46% 0.02 265);
  --gray-400: oklch(68% 0.015 265);
  --gray-300: oklch(78% 0.012 265);
  --gray-200: oklch(88% 0.008 265);
  --white: oklch(97% 0.005 95);
  --yellow-500: #eab308;
  --yellow-400: #facc15;
  --accent: var(--yellow-500);
  --accent-ink: oklch(24% 0.05 90);

  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --text-sm: 0.875rem;
  --text-base: 1.0625rem;
  --text-lg: clamp(1.15rem, 1rem + 0.7vw, 1.4rem);
  --text-xl: clamp(1.4rem, 1.2rem + 1vw, 1.85rem);
  --text-2xl: clamp(1.9rem, 1.4rem + 2.2vw, 2.8rem);
  --text-hero: clamp(2.4rem, 1.6rem + 3.6vw, 4rem);

  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.75rem;
  --space-4: 3rem;
  --section: clamp(4rem, 3rem + 5vw, 7.5rem);

  --radius: 8px;
  --container: 72rem;
  --container-wide: 80rem;

  color-scheme: dark;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition: none !important;
  }
}

body {
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(circle at 82% -8%, oklch(80% 0.16 90 / 13%), transparent 38rem),
    linear-gradient(180deg, var(--gray-950) 0%, var(--gray-900) 55%, var(--gray-950) 100%);
  color: var(--gray-200);
  font-family: var(--sans);
  font-size: var(--text-base);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* Signature top accent: fixed to the viewport on wide screens;
   scrolls with the page on phones/tablets, where fixed elements fight
   the collapsing browser chrome. */
body::before {
  content: "";
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  height: 5px;
  background: var(--accent);
}

@media (max-width: 63.99rem) {
  body {
    border-top: 5px solid var(--accent);
  }

  body::before {
    display: none;
  }
}

a {
  color: inherit;
}

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

h1,
h2,
h3 {
  margin: 0 0 var(--space-2);
  color: var(--white);
  font-weight: 800;
  letter-spacing: -0.015em;
  line-height: 1.12;
  text-wrap: balance;
}

p {
  margin: 0 0 var(--space-2);
}

code {
  font-family: var(--mono);
  font-size: 0.85em;
  color: var(--white);
}

kbd {
  display: inline-grid;
  place-items: center;
  min-width: 1.65em;
  height: 1.65em;
  padding: 0 0.3em;
  border: 1px solid var(--gray-600);
  border-bottom-width: 2px;
  border-radius: 5px;
  background: var(--gray-950);
  color: var(--yellow-400);
  font-family: var(--mono);
  font-size: 0.8em;
  font-weight: 700;
  line-height: 1;
  vertical-align: -0.2em;
}

.eyebrow {
  margin: 0 0 var(--space-1);
  color: var(--yellow-400);
  font-size: var(--text-sm);
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* ---------- header ---------- */

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  width: min(var(--container), 100% - 2.5rem);
  margin-inline: auto;
  padding-block: var(--space-3);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--white);
  font-size: 1.1rem;
  font-weight: 800;
  text-decoration: none;
}

.brand img {
  border-radius: 8px;
}

.site-header nav {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-weight: 600;
  font-size: var(--text-sm);
}

.site-header nav a {
  color: var(--gray-300);
  text-decoration: none;
}

.site-header nav a:hover {
  color: var(--white);
}

.nav-button {
  padding: 0.5rem 1.1rem;
  border: 1px solid var(--yellow-500);
  border-radius: var(--radius);
  color: var(--yellow-400) !important;
}

.nav-button:hover {
  background: oklch(80% 0.16 90 / 10%);
}

/* ---------- hero ---------- */

.hero {
  display: grid;
  grid-template-columns: minmax(19rem, 0.9fr) minmax(0, 1.25fr);
  gap: clamp(2rem, 4vw, 4rem);
  align-items: center;
  width: min(var(--container-wide), 100% - 2.5rem);
  margin-inline: auto;
  padding-block: clamp(1.5rem, 4vw, 3.5rem) var(--section);
}

.hero h1 {
  margin-bottom: var(--space-2);
  font-size: var(--text-hero);
}

.lede {
  max-width: 34rem;
  margin-bottom: var(--space-3);
  color: var(--gray-300);
  font-size: var(--text-lg);
  line-height: 1.55;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.primary-action,
.secondary-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 3.2rem;
  padding: 0 1.5rem;
  border-radius: var(--radius);
  font-weight: 700;
  text-decoration: none;
}

.primary-action {
  background: var(--accent);
  color: var(--accent-ink);
  box-shadow: 0 14px 34px oklch(80% 0.16 90 / 22%);
}

.primary-action:hover {
  background: var(--yellow-400);
}

.secondary-action {
  border: 1px solid var(--gray-600);
  color: var(--gray-200);
}

.secondary-action:hover {
  border-color: var(--gray-400);
  color: var(--white);
}

/* ---------- the live preview window ---------- */

.product-shot {
  min-width: 0;
}

.window {
  overflow: hidden;
  border: 1px solid oklch(78% 0.012 265 / 16%);
  border-radius: 10px;
  background: var(--gray-900);
  box-shadow: 0 32px 90px oklch(5% 0.02 265 / 65%);
}

.window-top {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  height: 2.4rem;
  padding: 0 0.9rem;
  border-bottom: 1px solid var(--gray-700);
  background: var(--gray-950);
}

.window-top span {
  width: 0.7rem;
  height: 0.7rem;
  border-radius: 50%;
  background: var(--gray-600);
}

.window-top span:first-child {
  background: oklch(63% 0.2 25);
}

.window-top span:nth-child(2) {
  background: oklch(78% 0.16 75);
}

.window-top span:nth-child(3) {
  background: oklch(72% 0.18 140);
}

.window-title {
  margin: 0 auto;
  padding-right: 3.1rem; /* visually centre against the traffic lights */
  color: var(--gray-400);
  font-family: var(--mono);
  font-size: 0.7rem;
}

.classifier-preview {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(15rem, 1fr);
}

.record-pane {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.75rem;
  padding: clamp(1.25rem, 2.5vw, 2rem);
  background: var(--gray-950);
}

.record-pane img {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border-radius: var(--radius);
  box-shadow: 0 18px 44px oklch(5% 0.02 265 / 45%);
}

.record-meta {
  margin: 0;
  color: var(--gray-400);
  font-family: var(--mono);
  font-size: 0.72rem;
}

.question-pane {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: clamp(1.25rem, 2.5vw, 2rem) clamp(1.1rem, 2vw, 1.6rem);
  border-left: 1px solid var(--gray-700);
  background: var(--gray-900);
}

.question-count {
  margin-bottom: var(--space-1);
  color: var(--yellow-400);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.question-pane h2 {
  margin-bottom: var(--space-2);
  font-size: var(--text-xl);
}

.choice {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  width: 100%;
  margin-bottom: var(--space-1);
  padding: 0.8rem 0.9rem;
  border: 1px solid var(--gray-600);
  border-radius: var(--radius);
  background: var(--gray-800);
  color: var(--gray-200);
  font: 600 1rem var(--sans);
  text-align: left;
  cursor: pointer;
  transition: border-color 120ms ease-out, background-color 120ms ease-out, transform 80ms ease-out;
}

.choice:hover {
  background: var(--gray-700);
}

.choice:active {
  transform: scale(0.985);
}

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

.choice kbd {
  min-width: 1.9em;
  height: 1.9em;
  font-size: 0.85rem;
}

.choice.selected {
  border-color: var(--yellow-500);
  background: oklch(80% 0.16 90 / 12%);
  color: var(--white);
}

.deck-status {
  margin: var(--space-1) 0 0;
  color: var(--gray-400);
  font-size: var(--text-sm);
}

.status-strip {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--space-1) var(--space-2);
  padding: 0.7rem 1rem;
  border-top: 1px solid var(--gray-700);
  background: var(--gray-950);
  color: var(--gray-300);
  font-size: var(--text-sm);
  font-weight: 600;
}

.status-strip span {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  white-space: nowrap;
}

.status-strip span::before {
  content: "";
  width: 0.55rem;
  height: 0.55rem;
  border-radius: 50%;
  background: var(--yellow-500);
}

.shot-note {
  margin: var(--space-2) 0 0;
  color: var(--gray-400);
  font-size: var(--text-sm);
  text-align: right;
}

/* ---------- features ---------- */

.feature-band {
  width: min(var(--container), 100% - 2.5rem);
  margin-inline: auto;
  padding-top: var(--space-4);
  padding-bottom: var(--section);
  border-top: 1px solid var(--gray-700);
}

.section-heading {
  max-width: 42rem;
  margin-bottom: var(--space-4);
}

.section-heading h2,
.positioning h2,
.download h2 {
  font-size: var(--text-2xl);
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: var(--space-2);
}

.features article {
  padding: var(--space-3);
  border: 1px solid var(--gray-700);
  border-radius: 10px;
  background: oklch(37% 0.022 265 / 35%);
}

.features h3 {
  font-size: var(--text-lg);
}

.features p {
  margin: 0;
  color: var(--gray-300);
}

/* ---------- positioning ---------- */

.positioning {
  display: grid;
  grid-template-columns: minmax(16rem, 0.95fr) minmax(0, 1.05fr);
  gap: clamp(1.5rem, 4vw, 4rem);
  align-items: center;
  width: min(var(--container), 100% - 2.5rem);
  margin-inline: auto;
  padding-top: var(--space-4);
  padding-bottom: var(--section);
  border-top: 1px solid var(--gray-700);
}

.positioning h2 {
  margin-bottom: 0;
}

.positioning > p {
  margin: 0;
  color: var(--gray-300);
  font-size: var(--text-lg);
  line-height: 1.6;
}

/* ---------- download ---------- */

.download {
  width: min(var(--container), 100% - 2.5rem);
  margin-inline: auto;
  padding-top: var(--space-4);
  padding-bottom: var(--section);
  border-top: 1px solid var(--gray-700);
}

.platforms {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(13rem, 1fr));
  gap: var(--space-2);
  margin: 0 0 var(--space-3);
  padding: 0;
  list-style: none;
}

.platforms a {
  display: grid;
  gap: 0.2rem;
  padding: 1.2rem 1.4rem;
  border: 1px solid var(--gray-700);
  border-radius: 10px;
  background: oklch(37% 0.022 265 / 35%);
  text-decoration: none;
  transition: border-color 120ms ease-out;
}

.platforms a:hover {
  border-color: var(--yellow-500);
}

.platforms strong {
  color: var(--white);
  font-size: var(--text-lg);
  font-weight: 800;
}

.platforms span {
  color: var(--gray-400);
  font-size: var(--text-sm);
}

.download-note {
  margin: 0;
  color: var(--gray-400);
  font-size: var(--text-sm);
}

.download-note a {
  color: var(--yellow-400);
}

/* ---------- footer ---------- */

footer {
  width: min(var(--container), 100% - 2.5rem);
  margin-inline: auto;
  padding: var(--space-3) 0 var(--space-4);
  border-top: 1px solid var(--gray-700);
  color: var(--gray-400);
  font-size: var(--text-sm);
}

footer a {
  color: var(--gray-300);
  font-weight: 600;
}

footer a:hover {
  color: var(--white);
}

/* ---------- responsive ---------- */

@media (max-width: 64rem) {
  .hero {
    grid-template-columns: 1fr;
  }

  .shot-note {
    text-align: left;
  }

  .positioning {
    grid-template-columns: 1fr;
    align-items: start;
  }
}

@media (max-width: 46rem) {
  .classifier-preview {
    grid-template-columns: 1fr;
  }

  .question-pane {
    border-left: 0;
    border-top: 1px solid var(--gray-700);
  }

  .status-strip {
    justify-content: flex-start;
  }
}

@media (max-width: 30rem) {
  .actions {
    flex-direction: column;
    align-items: stretch;
  }

  .site-header nav {
    gap: var(--space-2);
  }

  .window-title {
    display: none;
  }
}