/* ==========================================================================
   Arena Phase 0 placeholder UI — layout primitives ONLY.
   Colors/type/radii come from css/tokens.css (copy of design/tokens.css,
   source of truth owned by A-DESIGN). No ad-hoc color values here.
   ========================================================================== */

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

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

body {
  margin: 0;
  min-height: 100dvh;
  background: var(--bg-base);
  color: var(--text-hi);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.5;
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-header);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 16px;
  background: color-mix(in srgb, var(--bg-base) 88%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--hairline);
}

.wordmark {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 20px;
  letter-spacing: -0.02em;
  color: var(--text-hi);
}
.wordmark:hover { text-decoration: none; }
.wordmark .dot { color: var(--brand-fg); }

.site-nav { display: flex; align-items: center; gap: 8px; }

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

.container {
  width: 100%;
  max-width: 480px; /* phone-first column; widened per page if needed */
  margin: 0 auto;
  padding: 24px 16px 48px;
}

.card {
  background: var(--bg-elevated);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  padding: 24px 20px;
}

.stack > * + * { margin-top: 16px; }

.muted { color: var(--text-mid); }
.small { font-size: 14px; }

h1, h2 {
  font-family: var(--font-display);
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin: 0;
}

/* --- forms ------------------------------------------------------------------ */

.field label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-mid);
  margin-bottom: 6px;
}

.input {
  display: block;
  width: 100%;
  min-height: var(--touch-min);
  padding: 10px 14px;
  font: inherit;
  color: var(--text-hi);
  background: var(--bg-overlay);
  border: 1px solid var(--hairline-strong);
  border-radius: var(--radius-md);
  transition: border-color var(--dur-hover) var(--ease-standard), box-shadow var(--dur-hover) var(--ease-standard);
}
.input::placeholder { color: var(--text-placeholder); }
.input:focus {
  outline: none;
  border-color: var(--brand-400);
  box-shadow: var(--focus-ring);
}

.field-error {
  margin-top: 6px;
  font-size: 13px;
  color: var(--danger-fg);
}

.check-row { display: flex; align-items: center; gap: 8px; font-size: 14px; color: var(--text-mid); }
.check-row input { width: 18px; height: 18px; accent-color: var(--brand-fill); }

/* --- buttons ----------------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: var(--touch-min);
  padding: 10px 20px;
  font: inherit;
  font-weight: 600;
  border: 1px solid transparent;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: background var(--dur-hover) var(--ease-standard), transform var(--dur-press) var(--ease-standard);
}
.btn:active { transform: scale(0.97); }
.btn-block { width: 100%; }

.btn-primary {
  background: var(--brand-fill);
  color: var(--text-on-brand);
}
.btn-primary:hover { background: var(--brand-fill-hover); text-decoration: none; }
.btn-primary:active { background: var(--brand-fill-active); }

.btn-ghost {
  background: transparent;
  color: var(--text-hi);
  border-color: var(--hairline-strong);
}
.btn-ghost:hover { border-color: var(--text-mid); text-decoration: none; }

/* --- feedback ------------------------------------------------------------------ */

.alert {
  padding: 12px 16px;
  border-radius: var(--radius-md);
  font-size: 14px;
  border: 1px solid var(--hairline);
  background: var(--bg-overlay);
}
.alert-success { border-color: var(--success-fg); color: var(--success-fg); }

/* --- landing --------------------------------------------------------------------- */

.hero { text-align: center; padding: 64px 0 32px; }
.hero h1 { font-size: clamp(34px, 9vw, 52px); }
.hero .tagline { color: var(--text-mid); font-size: 17px; max-width: 30ch; margin: 12px auto 0; }
.hero .cta-row { display: flex; flex-direction: column; gap: 12px; margin-top: 32px; }

.live-dot {
  display: inline-block;
  width: 8px; height: 8px;
  border-radius: var(--radius-full);
  background: var(--live-fg);
  box-shadow: var(--glow-live);
  margin-right: 6px;
  vertical-align: middle;
}

@media (min-width: 480px) {
  .hero .cta-row { flex-direction: row; justify-content: center; }
}