/* -------------------------------------------------------------------------
   symmetrylab.app
   ------------------------------------------------------------------------- */

@font-face {
  font-family: 'Newsreader';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('/assets/fonts/newsreader.woff2') format('woff2');
}

/* -- tokens ---------------------------------------------------------------- */

:root {
  --bg:           #000000;
  --bg-elev:      #0d0d0f;
  --ink:          #f0ebe2;
  --ink-dim:      #a9a49b;
  --ink-muted:    #6d6a62;
  --rule:         #1c1c20;
  --rule-strong:  #2e2e34;

  --font-display: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Segoe UI", system-ui, sans-serif;
  --font-body:    'Newsreader', Georgia, 'Times New Roman', serif;

  --space-1:  0.5rem;
  --space-2:  1rem;
  --space-3:  1.5rem;
  --space-4:  2.5rem;
  --space-5:  4rem;
  --space-6:  6rem;
  --space-7:  9rem;

  --measure:      42rem;  /* ~672px for long-form reading */
  --content-max: 72rem;   /* 1152px cap for sections */

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
}

/* -- reset ----------------------------------------------------------------- */

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body, h1, h2, h3, p, figure, blockquote, dl, dd { margin: 0; }
img, svg, video { display: block; max-width: 100%; height: auto; }
input, button, textarea { font: inherit; color: inherit; }
button { border: 0; background: none; cursor: pointer; }

/* -- base ------------------------------------------------------------------ */

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1.0625rem;     /* 17px */
  line-height: 1.65;
  font-feature-settings: "kern", "liga", "calt";
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

a {
  color: var(--ink);
  text-decoration: none;
  text-decoration-color: var(--rule-strong);
  text-underline-offset: 0.2em;
  transition: text-decoration-color 200ms ease, color 200ms ease;
}
a:hover { text-decoration: underline; text-decoration-color: var(--ink-dim); }

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

::selection { background: var(--ink); color: var(--bg); }

/* -- typography ------------------------------------------------------------ */

.display {
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.02;
}
h1, h2, h3 { font-family: var(--font-display); font-weight: 600; letter-spacing: -0.02em; }
h1 { font-size: clamp(2.5rem, 6vw, 4.5rem); line-height: 1.02; }
h2 { font-size: clamp(2rem, 4vw, 3rem);     line-height: 1.08; }
h3 { font-size: 1.25rem; line-height: 1.3; }
p  { hanging-punctuation: first last; }

/* -- layout ---------------------------------------------------------------- */

.container {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding-inline: clamp(1.25rem, 4vw, 2.5rem);
}

section { padding-block: var(--space-6); }
@media (max-width: 720px) { section { padding-block: var(--space-5); } }

.divider {
  border: 0;
  border-top: 1px solid var(--rule);
  margin: 0;
}

/* -- site chrome ----------------------------------------------------------- */

.site-header {
  padding-block: var(--space-3);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}
.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1rem;
  letter-spacing: -0.01em;
  color: var(--ink);
}
.site-header__brand img {
  width: 28px; height: 28px;
  border-radius: 7px;
}
.site-header__nav {
  display: flex;
  gap: var(--space-3);
  font-family: var(--font-display);
  font-size: 0.875rem;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}
.site-header__nav a { color: var(--ink-dim); }
.site-header__nav a:hover { color: var(--ink); }
@media (max-width: 520px) {
  .site-header__nav { display: none; }
}

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

.hero {
  padding-block: clamp(3rem, 7vw, 6rem) var(--space-6);
}
.hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-5);
  align-items: center;
}
@media (min-width: 900px) {
  .hero__grid {
    grid-template-columns: minmax(0, 1fr) minmax(280px, 360px);
    gap: var(--space-5);
  }
}
@media (min-width: 1200px) {
  .hero__grid { grid-template-columns: minmax(0, 1fr) 380px; }
}

.hero__title {
  margin-bottom: var(--space-3);
}
@media (min-width: 640px) {
  .hero__title { white-space: nowrap; }
}
.hero__tagline {
  font-size: clamp(1.125rem, 1.5vw, 1.375rem);
  line-height: 1.45;
  color: var(--ink-dim);
  margin-bottom: var(--space-4);
}
@media (min-width: 640px) {
  .hero__tagline { white-space: nowrap; }
}

.app-store-badge {
  display: inline-block;
  transition: transform 200ms ease, filter 200ms ease;
}
.app-store-badge img { height: 52px; width: auto; }
.app-store-badge:hover { transform: translateY(-1px); filter: drop-shadow(0 6px 20px rgba(255,255,255,0.08)); }

/* Hero video — vertical phone-shape clip */
.hero__video-wrap {
  position: relative;
  width: 100%;
  max-width: 380px;
  margin-inline: auto;
  aspect-ratio: 1320 / 2738;  /* source cropped above status bar */
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--bg-elev);
  box-shadow:
    0 30px 80px rgba(0,0,0,0.5),
    0 0 0 1px var(--rule) inset;
}
.hero__video-wrap video {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
}
@media (min-width: 900px) {
  .hero__video-wrap { max-width: 360px; }
}

/* -- the wordmark — one moment of delight -------------------------------- */

.wordmark {
  font-family: var(--font-display);
  font-weight: 650;
  letter-spacing: -0.025em;
  line-height: 1.0;
  color: var(--ink);
}

/* -- what-it-does ---------------------------------------------------------- */

.about {
  border-top: 1px solid var(--rule);
}
.about__eyebrow {
  font-family: var(--font-display);
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin-bottom: var(--space-3);
}
.about__lead {
  font-size: clamp(1.35rem, 2.2vw, 1.75rem);
  line-height: 1.42;
  max-width: var(--measure);
}
.about__lead + .about__lead { margin-top: var(--space-3); color: var(--ink-dim); }

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

.features { border-top: 1px solid var(--rule); }
.features__heading {
  margin-bottom: var(--space-5);
  max-width: 20ch;
}
.features__list { list-style: none; padding: 0; margin: 0; }
.features__item {
  display: grid;
  grid-template-columns: 4rem 1fr;
  gap: var(--space-3);
  align-items: baseline;
  padding-block: var(--space-3);
  border-top: 1px solid var(--rule);
}
.features__item:last-child { border-bottom: 1px solid var(--rule); }
.features__num {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1rem;
  color: var(--ink-muted);
  letter-spacing: 0.04em;
  font-variant-numeric: tabular-nums;
}
.features__body {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 2fr);
  gap: var(--space-3);
  align-items: baseline;
}
.features__title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(1.125rem, 1.6vw, 1.375rem);
  letter-spacing: -0.01em;
  line-height: 1.15;
}
.features__desc {
  color: var(--ink-dim);
  line-height: 1.55;
  max-width: 34rem;
}
@media (max-width: 720px) {
  .features__item { grid-template-columns: 2.5rem 1fr; gap: var(--space-2); }
  .features__body { grid-template-columns: 1fr; gap: var(--space-1); }
}

/* -- signup ---------------------------------------------------------------- */

.signup { border-top: 1px solid var(--rule); }
.signup__inner {
  max-width: var(--measure);
}
.signup__heading { margin-bottom: var(--space-3); }
.signup__copy {
  font-size: 1.125rem;
  color: var(--ink-dim);
  max-width: 38ch;
  margin-bottom: var(--space-4);
}

.signup-btn {
  display: inline-block;
  padding: 1rem 1.75rem;
  background: var(--ink);
  color: var(--bg);
  border-radius: 999px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.02em;
  text-decoration: none;
  transition: transform 150ms ease, background 200ms ease;
}
.signup-btn:hover {
  transform: translateY(-1px);
  background: #fff;
  text-decoration: none;
  color: var(--bg);
}
.signup-btn:active { transform: translateY(0); }
.signup-btn.is-loading {
  opacity: 0.72;
  cursor: progress;
}
.signup-btn.is-loading::after {
  content: "";
  display: inline-block;
  width: 0.7em; height: 0.7em;
  margin-left: 0.6em;
  vertical-align: -0.06em;
  border: 1.5px solid currentColor;
  border-top-color: transparent;
  border-radius: 50%;
  animation: signup-spin 0.7s linear infinite;
}
@keyframes signup-spin { to { transform: rotate(360deg); } }
@media (prefers-reduced-motion: reduce) {
  .signup-btn.is-loading::after { animation: none; }
}

.signup__sign {
  margin-top: var(--space-3);
  color: var(--ink-muted);
}

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

.site-footer {
  border-top: 1px solid var(--rule);
  padding-block: var(--space-5);
  color: var(--ink-muted);
  font-family: var(--font-display);
  font-size: 0.9375rem;
}
.site-footer .container {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  justify-content: space-between;
  align-items: baseline;
}
.site-footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}
.site-footer a { color: var(--ink-dim); }
.site-footer a:hover { color: var(--ink); }

/* -- reading pages (privacy, support, 404) -------------------------------- */

.reading {
  padding-block: var(--space-5) var(--space-6);
}
.reading__inner {
  max-width: var(--measure);
  margin-inline: auto;
}
.reading h1 {
  font-size: clamp(2.25rem, 4vw, 3rem);
  margin-bottom: var(--space-1);
}
.reading .lede {
  color: var(--ink-dim);
  font-style: italic;
  margin-bottom: var(--space-4);
}
.reading h2 {
  font-size: 1.35rem;
  margin-top: var(--space-4);
  margin-bottom: var(--space-2);
  letter-spacing: -0.01em;
}
.reading p {
  margin-block: 0.75em;
  color: var(--ink);
}
.reading p + p { margin-top: 1em; }
.reading a { text-decoration: underline; text-decoration-color: var(--rule-strong); }
.reading a:hover { text-decoration-color: var(--ink); }

.reading .contact-block {
  border: 1px solid var(--rule-strong);
  border-radius: var(--radius-md);
  padding: var(--space-3);
  background: var(--bg-elev);
  margin-block: var(--space-4);
}
.reading .contact-block strong { font-family: var(--font-display); font-weight: 600; }
.reading .contact-block .hint { display: block; color: var(--ink-muted); font-size: 0.9375rem; margin-top: 0.3rem; }

/* details/summary for support FAQ */
.reading details {
  border-top: 1px solid var(--rule);
  padding: var(--space-2) 0;
}
.reading details:last-of-type { border-bottom: 1px solid var(--rule); }
.reading summary {
  cursor: pointer;
  font-family: var(--font-display);
  font-weight: 550;
  font-size: 1.0625rem;
  padding: 0.3rem 0;
  list-style: none;
  display: flex;
  justify-content: space-between;
  gap: var(--space-2);
}
.reading summary::-webkit-details-marker { display: none; }
.reading summary::after {
  content: "+";
  font-family: var(--font-display);
  font-weight: 400;
  color: var(--ink-muted);
  transition: transform 200ms ease;
}
.reading details[open] summary::after { content: "–"; }
.reading details p {
  color: var(--ink-dim);
  margin-top: 0.5rem;
}

/* -- utilities ------------------------------------------------------------- */

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