/* ==========================================================================
   Altie Reality — Design System
   Tokens, primitives and components for the 2026 site.
   ========================================================================== */

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

html { -webkit-text-size-adjust: 100%; }

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd, ul, ol {
  margin: 0;
  padding: 0;
}

ul[class], ol[class] { list-style: none; }

img, svg, video, canvas {
  display: block;
  max-width: 100%;
  height: auto;
}

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

a { color: inherit; }

/* --- Tokens --------------------------------------------------------------- */
:root {
  /* Surfaces — deep, blue-cast near-black. */
  --ink-000: #04060b;
  --ink-050: #070a11;
  --ink-100: #0b0f18;
  --ink-200: #111624;
  --ink-300: #19203042;

  /* Light surfaces for strategic contrast sections. */
  --paper-000: #f5f7fb;
  --paper-100: #eceff6;
  --paper-200: #dfe4ee;

  /* Type on dark. */
  --text-1: #f3f6fb;
  --text-2: #a8b2c4;
  --text-3: #6e7a8e;

  /* Type on light. */
  --text-1-inv: #0a1020;
  --text-2-inv: #47526a;
  --text-3-inv: #5f6a7d;   /* 5.09:1 on --paper-000 */

  /* Brand — evolved from the existing #4154f1 for dark-surface legibility. */
  --brand: #4560e8;        /* filled surfaces — 5.13:1 with white */
  --brand-hover: #5069ec;  /* 4.59:1 with white */
  --brand-bright: #7d99ff; /* text/accents on dark — 7.60:1 */
  --brand-deep: #3a53d6;   /* text on light — 5.78:1 */
  --signal: #57e2e9;      /* technical / data accent, used sparingly */

  /* Hairlines and glows. */
  --line: rgba(255, 255, 255, 0.09);
  --line-strong: rgba(255, 255, 255, 0.16);
  --line-inv: rgba(10, 16, 32, 0.12);
  --glow: rgba(69, 96, 232, 0.32);

  /* Spacing scale — 4px base. */
  --s1: 0.25rem;  --s2: 0.5rem;   --s3: 0.75rem;  --s4: 1rem;
  --s5: 1.5rem;   --s6: 2rem;     --s7: 2.5rem;   --s8: 3rem;
  --s9: 4rem;     --s10: 5rem;    --s11: 6.5rem;  --s12: 8rem;

  /* Section rhythm. */
  --section-y: clamp(4.5rem, 8vw, 8.5rem);
  --gutter: clamp(1.25rem, 4vw, 2.5rem);

  /* Radii — restrained. */
  --r-sm: 4px;
  --r-md: 8px;
  --r-lg: 14px;
  --r-xl: 22px;

  /* Type families. */
  --font-display: "Inter Tight", "Inter", -apple-system, BlinkMacSystemFont,
    "Segoe UI", Helvetica, Arial, sans-serif;
  --font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI",
    Helvetica, Arial, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  /* Type scale. */
  --t-display: clamp(2.6rem, 6vw, 5rem);
  --t-h1: clamp(2.25rem, 4.6vw, 3.9rem);
  --t-h2: clamp(1.85rem, 3.2vw, 2.75rem);
  --t-h3: clamp(1.3rem, 1.9vw, 1.7rem);
  --t-h4: clamp(1.08rem, 1.3vw, 1.25rem);
  --t-lead: clamp(1.05rem, 1.25vw, 1.24rem);
  --t-body: 1rem;
  --t-small: 0.9rem;
  --t-label: 0.72rem;

  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --header-h: 72px;
}

/* --- Base ----------------------------------------------------------------- */
html { scroll-behavior: smooth; }

body {
  background: var(--ink-000);
  color: var(--text-1);
  font-family: var(--font-body);
  font-size: var(--t-body);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  font-feature-settings: "cv11", "ss01";
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.08;
  letter-spacing: -0.025em;
  text-wrap: balance;
}

h1 { font-size: var(--t-h1); }
h2 { font-size: var(--t-h2); }
h3 { font-size: var(--t-h3); letter-spacing: -0.018em; line-height: 1.2; }
h4 { font-size: var(--t-h4); letter-spacing: -0.012em; line-height: 1.3; }

p { text-wrap: pretty; }

::selection { background: var(--brand); color: #fff; }

/* Focus — visible, never removed. */
:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 3px;
  border-radius: var(--r-sm);
}

.skip-link {
  position: absolute;
  left: var(--s4);
  top: -100px;
  z-index: 200;
  background: var(--brand);
  color: #fff;
  padding: var(--s3) var(--s5);
  border-radius: var(--r-md);
  font-weight: 600;
  transition: top 0.2s var(--ease);
}
.skip-link:focus { top: var(--s4); }

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

/* --- Layout primitives ---------------------------------------------------- */
.container {
  width: 100%;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.container--wide { max-width: 1400px; }
.container--narrow { max-width: 780px; }

.section { padding-block: var(--section-y); position: relative; }
.section--tight { padding-block: clamp(3rem, 5vw, 5rem); }
.section--flush-top { padding-top: 0; }

/* Light section — strategic contrast. */
.section--paper {
  background: var(--paper-000);
  color: var(--text-1-inv);
}
.section--paper h1, .section--paper h2,
.section--paper h3, .section--paper h4 { color: var(--text-1-inv); }
.section--paper p { color: var(--text-2-inv); }
.section--paper .eyebrow { color: var(--brand-deep); }
.section--paper .eyebrow::before { background: var(--brand-deep); }

.section--raised { background: var(--ink-050); }

.stack > * + * { margin-top: var(--s4); }
.stack-lg > * + * { margin-top: var(--s6); }

.grid { display: grid; gap: var(--s6); }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

@media (max-width: 960px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 600px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: minmax(0, 1fr); }
}

/* Split layout: content + media. */
.split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 5rem);
  align-items: center;
}
.split--wide-text { grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); }
@media (max-width: 900px) {
  .split, .split--wide-text { grid-template-columns: minmax(0, 1fr); }
}

/* --- Type helpers --------------------------------------------------------- */
.eyebrow {
  font-family: var(--font-mono);
  font-size: var(--t-label);
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--brand-bright);
  display: inline-flex;
  align-items: center;
  gap: var(--s3);
  margin-bottom: var(--s4);
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--brand-bright);
  flex: none;
}
.eyebrow--plain::before { display: none; }

.display { font-size: var(--t-display); letter-spacing: -0.035em; }

.lead {
  font-size: var(--t-lead);
  line-height: 1.6;
  color: var(--text-2);
}
.section--paper .lead { color: var(--text-2-inv); }

.muted { color: var(--text-2); }
.section--paper .muted { color: var(--text-2-inv); }

.mono-label {
  font-family: var(--font-mono);
  font-size: var(--t-label);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-3);
}

.section-head { max-width: 760px; margin-bottom: clamp(2.5rem, 4vw, 4rem); }
.section-head--center { margin-inline: auto; text-align: center; }
.section-head--center .eyebrow { justify-content: center; }
.section-head p { margin-top: var(--s5); }

/* --- Buttons -------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--s3);
  padding: 0.9rem 1.6rem;
  border-radius: var(--r-md);
  border: 1px solid transparent;
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: -0.005em;
  text-decoration: none;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.22s var(--ease), border-color 0.22s var(--ease),
    transform 0.22s var(--ease), box-shadow 0.22s var(--ease), color 0.22s var(--ease);
}

.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }

.btn--primary {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 8px 28px -10px var(--glow);
}
.btn--primary:hover {
  background: var(--brand-hover);
  box-shadow: 0 14px 34px -10px var(--glow);
}

.btn--ghost {
  border-color: var(--line-strong);
  color: var(--text-1);
  background: rgba(255, 255, 255, 0.02);
}
.btn--ghost:hover {
  border-color: var(--brand);
  background: rgba(91, 124, 255, 0.08);
}

.section--paper .btn--ghost {
  border-color: var(--line-inv);
  color: var(--text-1-inv);
  background: transparent;
}
.section--paper .btn--ghost:hover {
  border-color: var(--brand-deep);
  background: rgba(91, 124, 255, 0.06);
}

.btn--sm { padding: 0.62rem 1.1rem; font-size: 0.875rem; }
.btn--lg { padding: 1.05rem 2rem; font-size: 1rem; }

.btn-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s4);
  align-items: center;
}

/* Text link with animated rule. */
.link-arrow {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  gap: var(--s2);
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--brand-bright);
  text-decoration: none;
}
.link-arrow svg { transition: transform 0.25s var(--ease); flex: none; }
.link-arrow:hover svg { transform: translateX(4px); }
.section--paper .link-arrow { color: var(--brand-deep); }

/* --- Surfaces / cards ----------------------------------------------------- */
.card {
  background: linear-gradient(180deg, rgba(255,255,255,0.035), rgba(255,255,255,0.012));
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  padding: clamp(1.5rem, 2.4vw, 2rem);
  position: relative;
  transition: border-color 0.25s var(--ease), transform 0.25s var(--ease),
    background 0.25s var(--ease);
}
.card:hover { border-color: var(--line-strong); transform: translateY(-3px); }

.card h3 { margin-bottom: var(--s3); }
.card p { color: var(--text-2); font-size: 0.96rem; }

.section--paper .card {
  background: #fff;
  border-color: var(--line-inv);
  box-shadow: 0 1px 2px rgba(10, 16, 32, 0.04);
}
.section--paper .card:hover {
  border-color: rgba(91, 124, 255, 0.35);
  box-shadow: 0 12px 32px -18px rgba(10, 16, 32, 0.35);
}
.section--paper .card p { color: var(--text-2-inv); }

/* A card that is entirely a link. */
.card--link { text-decoration: none; display: block; }

/* Numbered index on a card. */
.card__index {
  font-family: var(--font-mono);
  font-size: var(--t-label);
  letter-spacing: 0.12em;
  color: var(--text-3);
  display: block;
  margin-bottom: var(--s5);
}

/* --- Media frames --------------------------------------------------------- */
.frame {
  position: relative;
  border-radius: var(--r-lg);
  overflow: hidden;
  border: 1px solid var(--line);
  background: var(--ink-100);
}
.frame img { width: 100%; height: 100%; object-fit: cover; display: block; }
.frame--ratio-4-3 { aspect-ratio: 4 / 3; }
.frame--ratio-16-9 { aspect-ratio: 16 / 9; }
.frame--ratio-1-1 { aspect-ratio: 1 / 1; }
.frame--ratio-3-4 { aspect-ratio: 3 / 4; }

/* Contain-fit frame for logos and screenshots that must not crop. */
.frame--contain { background: var(--ink-100); }
.frame--contain img { object-fit: contain; padding: var(--s5); }
/* Portrait sources (phone screenshots) need a squarer box and less inset,
   otherwise they float in a field of empty space. */
.frame--portrait { aspect-ratio: 1 / 1; }
.frame--portrait img { padding: var(--s4); }
@media (max-width: 600px) {
  .frame--portrait { aspect-ratio: 4 / 5; }
}

.section--paper .frame { border-color: var(--line-inv); background: #fff; }
.section--paper .frame--contain { background: #fff; }

/* --- Stats ---------------------------------------------------------------- */
.stat__value {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 3vw, 2.6rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1;
  color: var(--text-1);
}
.stat__label {
  font-family: var(--font-mono);
  font-size: var(--t-label);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-top: var(--s3);
  display: block;
}
.section--paper .stat__value { color: var(--text-1-inv); }

/* --- Pills / tags --------------------------------------------------------- */
.pill {
  display: inline-flex;
  align-items: center;
  gap: var(--s2);
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-2);
  background: rgba(255, 255, 255, 0.02);
}
.pill--accent {
  border-color: rgba(87, 226, 233, 0.35);
  color: var(--signal);
  background: rgba(87, 226, 233, 0.07);
}
.section--paper .pill { border-color: var(--line-inv); color: var(--text-2-inv); }

.pill-row { display: flex; flex-wrap: wrap; gap: var(--s3); }

/* --- Checklist ------------------------------------------------------------ */
.checklist { display: grid; gap: var(--s4); }
.checklist li {
  display: grid;
  grid-template-columns: 20px minmax(0, 1fr);
  gap: var(--s4);
  align-items: start;
  color: var(--text-2);
  font-size: 0.98rem;
}
.checklist svg { margin-top: 5px; color: var(--brand-bright); }
.section--paper .checklist li { color: var(--text-2-inv); }
.section--paper .checklist svg { color: var(--brand-deep); }

/* --- Reveal animation ----------------------------------------------------- */
/* Content is visible by default. The hidden start state is applied only
   when JS has confirmed it can reveal it again, so a script failure can
   never leave the page blank. */
.js-reveal [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
  transition-delay: var(--reveal-delay, 0ms);
}
.js-reveal [data-reveal].is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  .js-reveal [data-reveal] { opacity: 1; transform: none; }
}