/* TankTalk — shared stylesheet
   Self-contained: no external fonts, CDNs, or trackers.
   Light + dark aware via prefers-color-scheme. */

:root {
  /* Brand */
  --indigo: #5B56FA;
  --violet: #8B5CF6;
  --grad: linear-gradient(135deg, #5B56FA 0%, #8B5CF6 100%);

  /* Light theme */
  --bg: #ffffff;
  --bg-elev: #ffffff;
  --surface: #f6f6fb;
  --text: #1a1a2e;
  --text-muted: #565676;
  --border: rgba(91, 86, 250, 0.16);
  --shadow: 0 10px 30px -12px rgba(26, 26, 46, 0.18);
  --link: #4b46e0;

  /* Shape */
  --radius-card: 22px;
  --radius-btn: 14px;
  --maxw: 1080px;
  --measure: 68ch;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0e0e18;
    --bg-elev: #16161f;
    --surface: #16161f;
    --text: #f2f2f7;
    --text-muted: #a6a6c2;
    --border: rgba(139, 92, 246, 0.28);
    --shadow: 0 12px 34px -14px rgba(0, 0, 0, 0.6);
    --link: #a5a1ff;
  }
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: ui-rounded, "SF Pro Rounded", system-ui, -apple-system,
    "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 17px;
  line-height: 1.6;
  overflow-x: hidden;               /* never scroll horizontally */
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 64px;
}
.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.2rem;
  letter-spacing: -0.02em;
  color: var(--text);
}
.wordmark:hover { text-decoration: none; }
.wordmark .mark {
  width: 30px;
  height: 30px;
  border-radius: 8px;
  display: inline-block;
  object-fit: contain;
  box-shadow: 0 4px 12px -4px rgba(91, 86, 250, 0.5);
}
.nav {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}
.nav a {
  color: var(--text-muted);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 8px 12px;
  border-radius: 10px;
}
.nav a:hover { color: var(--text); background: var(--surface); text-decoration: none; }
.nav a[aria-current="page"] { color: var(--indigo); }

/* ---------- Footer ---------- */
.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 72px;
  padding: 32px 0;
  color: var(--text-muted);
  font-size: 0.9rem;
}
.site-footer .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.site-footer .nav a { padding: 6px 10px; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1rem;
  padding: 14px 22px;
  border-radius: var(--radius-btn);
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.06s ease, box-shadow 0.2s ease, opacity 0.2s ease;
}
.btn:hover { text-decoration: none; }
.btn:active { transform: translateY(1px); }
.btn-primary {
  background: var(--grad);
  color: #fff;
  box-shadow: 0 12px 26px -12px rgba(91, 86, 250, 0.75);
}
.btn-primary:hover { opacity: 0.94; }
.btn-secondary {
  background: var(--surface);
  color: var(--text);
  border-color: var(--border);
}

/* ---------- Hero ---------- */
.hero {
  background: var(--grad);
  color: #fff;
  padding: 88px 0 96px;
  text-align: center;
}
.hero h1 {
  margin: 0 auto 16px;
  max-width: 16ch;
  font-size: clamp(2.2rem, 6vw, 3.6rem);
  line-height: 1.08;
  letter-spacing: -0.03em;
  font-weight: 800;
}
.hero .subhead {
  margin: 0 auto 32px;
  max-width: 46ch;
  font-size: clamp(1.05rem, 2.4vw, 1.3rem);
  color: rgba(255, 255, 255, 0.92);
}
.hero .btn-primary {
  background: #fff;
  color: var(--indigo);
  box-shadow: 0 16px 34px -14px rgba(0, 0, 0, 0.4);
}
.btn .apple { display: inline-block; margin-top: -2px; }

/* ---------- Sections ---------- */
.section { padding: 64px 0; }
.section-title {
  text-align: center;
  font-size: clamp(1.6rem, 3.5vw, 2.2rem);
  letter-spacing: -0.02em;
  font-weight: 800;
  margin: 0 0 8px;
}
.section-sub {
  text-align: center;
  color: var(--text-muted);
  max-width: 52ch;
  margin: 0 auto 44px;
}

/* ---------- Squircle cards ---------- */
.cards {
  display: grid;
  gap: 20px;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}
.card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow);
  padding: 28px;
}
.card h3 {
  margin: 0 0 10px;
  font-size: 1.2rem;
  letter-spacing: -0.01em;
}
.card p { margin: 0 0 6px; color: var(--text-muted); }
.card .icon {
  width: 46px;
  height: 46px;
  border-radius: 13px;
  background: var(--grad);
  display: grid;
  place-items: center;
  margin-bottom: 16px;
  color: #fff;
  font-size: 1.4rem;
}
.card.span-2 { grid-column: span 2; }
@media (max-width: 640px) { .card.span-2 { grid-column: span 1; } }

/* ---------- App screenshots ---------- */
.shots {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 32px;
}
.shot {
  margin: 0;
  width: 260px;
  max-width: 78%;
}
.shot img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 30px;
  border: 1px solid var(--border);
  box-shadow: 0 24px 60px -24px rgba(91, 86, 250, 0.5);
}
.shot figcaption {
  margin-top: 14px;
  text-align: center;
  font-weight: 600;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* Voice-prompt chips */
.prompts {
  list-style: none;
  padding: 0;
  margin: 14px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.prompts li {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 7px 14px;
  font-size: 0.9rem;
  color: var(--text);
}
.prompts li::before { content: "\201C"; }
.prompts li::after { content: "\201D"; }

/* ---------- Contact form ---------- */
.form-wrap { max-width: 640px; margin: 0 auto; }
.form-card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow);
  padding: 32px;
}
.field { margin-bottom: 18px; }
.field label {
  display: block;
  font-weight: 600;
  font-size: 0.92rem;
  margin-bottom: 6px;
}
.field input,
.field textarea {
  width: 100%;
  font: inherit;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px 14px;
}
.field input:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--indigo);
  box-shadow: 0 0 0 3px rgba(91, 86, 250, 0.18);
}
.field textarea { min-height: 140px; resize: vertical; }
.field .error {
  display: none;
  color: #d13c3c;
  font-size: 0.85rem;
  margin-top: 5px;
}
.field.invalid .error { display: block; }
.field.invalid input,
.field.invalid textarea { border-color: #d13c3c; }

/* Honeypot — visually hidden, off-screen, not display:none (bots skip hidden) */
.hp {
  position: absolute !important;
  left: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.form-note { color: var(--text-muted); font-size: 0.88rem; margin-top: 4px; }

.form-status {
  display: none;
  border-radius: 12px;
  padding: 14px 16px;
  margin-bottom: 20px;
  font-weight: 600;
}
.form-status.show { display: block; }
.form-status.success {
  background: rgba(52, 168, 83, 0.12);
  border: 1px solid rgba(52, 168, 83, 0.4);
  color: #1e7d38;
}
.form-status.error {
  background: rgba(209, 60, 60, 0.1);
  border: 1px solid rgba(209, 60, 60, 0.4);
  color: #c0392b;
}
@media (prefers-color-scheme: dark) {
  .form-status.success { color: #7ee29a; }
  .form-status.error { color: #ff9b9b; }
}

.btn[disabled] { opacity: 0.6; cursor: default; }

/* ---------- Legal / prose (privacy policy) ---------- */
.prose {
  max-width: var(--measure);
  margin: 0 auto;
}
.prose h1 {
  font-size: clamp(2rem, 5vw, 2.6rem);
  letter-spacing: -0.02em;
  margin: 0 0 8px;
}
.prose h2 {
  font-size: 1.5rem;
  letter-spacing: -0.01em;
  margin: 40px 0 12px;
  padding-top: 8px;
}
.prose h3 { font-size: 1.2rem; margin: 28px 0 8px; }
.prose h4 { font-size: 1.02rem; margin: 22px 0 6px; color: var(--text-muted); }
.prose p { margin: 0 0 16px; }
.prose ul { margin: 0 0 16px; padding-left: 1.3em; }
.prose li { margin: 0 0 8px; }
.prose a { color: var(--indigo); text-decoration: underline; text-underline-offset: 2px; }
.prose a:hover { color: var(--violet); }

/* Utility */
.center { text-align: center; }
.mt-32 { margin-top: 32px; }
.lead { font-size: 1.15rem; color: var(--text-muted); }

/* Respect reduced motion */
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}