/* ─── tokens — modern-minimal ─────────────────────────────────── */
:root {
  --bg:      oklch(99% 0.002 240);
  --surface: oklch(100% 0 0);
  --fg:      oklch(18% 0.012 250);
  --muted:   oklch(54% 0.012 250);
  --border:  oklch(92% 0.005 250);
  --accent:  oklch(58% 0.18 255);

  /* status colors */
  --ok:      oklch(52% 0.14 155);
  --err:     oklch(55% 0.19 25);

  /* derived — do not change */
  --accent-soft: color-mix(in oklch, var(--accent) 12%, transparent);
  --ok-soft:     color-mix(in oklch, var(--ok) 10%, var(--surface));
  --err-soft:    color-mix(in oklch, var(--err) 8%, var(--surface));
  --fg-soft:     color-mix(in oklch, var(--fg) 6%, transparent);

  --font-display: -apple-system, BlinkMacSystemFont, 'SF Pro Display', system-ui, sans-serif;
  --font-body:    -apple-system, BlinkMacSystemFont, 'SF Pro Text', system-ui, sans-serif;
  --font-mono:    ui-monospace, 'JetBrains Mono', 'SF Mono', Menlo, monospace;

  --fs-h1: clamp(34px, 5vw, 48px);
  --fs-h2: clamp(26px, 3.4vw, 36px);
  --fs-h3: 20px;
  --fs-lead: 17px;
  --fs-body: 15px;
  --fs-meta: 13px;

  --gap-xs: 8px;
  --gap-sm: 12px;
  --gap-md: 20px;
  --gap-lg: 32px;
  --gap-xl: 56px;
  --gap-2xl: 96px;
  --container: 1120px;
  --gutter: 24px;

  --radius: 10px;
  --radius-lg: 16px;
}

/* ─── reset & base ────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: 1.55;
  letter-spacing: -0.006em;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}
svg { display: block; }
button { font: inherit; cursor: pointer; }
p { text-wrap: pretty; }
:is(h1, h2, h3) { text-wrap: balance; }

/* ─── layout primitives ───────────────────────────────────────── */
.container {
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.section { padding-block: clamp(32px, 6vw, 64px); }
.stack {
  display: flex;
  flex-direction: column;

  > * + * { margin-top: var(--gap-md); }
}
.row { display: flex; align-items: center; gap: var(--gap-md); }
.row-between { display: flex; align-items: center; justify-content: space-between; gap: var(--gap-md); }

/* ─── type ────────────────────────────────────────────────────── */
h1 { font-family: var(--font-display); font-size: var(--fs-h1); line-height: 1.06; letter-spacing: -0.025em; margin: 0; }
h2 { font-family: var(--font-display); font-size: var(--fs-h2); line-height: 1.1; letter-spacing: -0.02em; margin: 0; }
h3 { font-size: var(--fs-h3); font-weight: 600; line-height: 1.3; letter-spacing: -0.01em; margin: 0; }
.lead { font-size: var(--fs-lead); line-height: 1.55; color: var(--muted); margin: 0; }
.eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0;
}
.meta { font-family: var(--font-mono); font-size: var(--fs-meta); color: var(--muted); }
.num  { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }

/* ─── chrome ──────────────────────────────────────────────────── */
.topnav {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in oklch, var(--bg) 88%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);

  .topnav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-block: 14px;
    gap: var(--gap-md);
  }

  .logo {
    font-family: var(--font-display);
    font-size: 18px;
    font-weight: 650;
    letter-spacing: -0.02em;
  }
}
.pagefoot {
  padding-block: var(--gap-lg);
  color: var(--muted);
  font-size: 13px;
  border-top: 1px solid var(--border);

  .row-between { flex-wrap: wrap; gap: var(--gap-sm); }

  .pagefoot-links {
    display: flex;
    gap: var(--gap-md);

    a {
      color: var(--muted);
      text-decoration: none;

      &:hover {
        color: var(--fg);
        text-decoration: underline;
      }
    }
  }
}

/* ─── buttons ─────────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 44px;
  padding: 11px 20px;
  border-radius: var(--radius);
  border: 1px solid transparent;
  font-size: 15px;
  font-weight: 550;
  letter-spacing: -0.01em;
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.05s ease;

  &:active { transform: translateY(1px); }

  &-primary {
    background: var(--accent);
    color: var(--surface);
    border-color: var(--accent);

    &:hover {
      background: color-mix(in oklch, var(--accent) 88%, black);
      border-color: color-mix(in oklch, var(--accent) 88%, black);
    }
    &:disabled {
      background: var(--border);
      border-color: var(--border);
      color: var(--muted);
      cursor: not-allowed;
    }
  }

  &-secondary {
    background: var(--surface);
    color: var(--fg);
    border-color: var(--border);

    &:hover { border-color: color-mix(in oklch, var(--fg) 40%, var(--border)); }
    &:disabled { color: var(--muted); cursor: not-allowed; }
  }
}
:is(.btn, .input, .select):focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ─── card / surface ──────────────────────────────────────────── */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
}

/* ─── pill / tag ──────────────────────────────────────────────── */
.pill {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 10px;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.05em;
  text-transform: uppercase;

  &-ok  { background: var(--ok-soft); color: var(--ok); }
  &-err { background: var(--err-soft); color: var(--err); }
}
.pill-pop { animation: pill-pop 0.35s cubic-bezier(0.34, 1.56, 0.64, 1) both; }
@keyframes pill-pop {
  0%   { transform: scale(0.7); opacity: 0; }
  100% { transform: scale(1); opacity: 1; }
}
.reveal-ok { color: var(--ok); }
.tag {
  display: inline-flex; align-items: center;
  padding: 4px 10px;
  background: transparent;
  color: var(--muted);
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: 12px;
  white-space: nowrap;
}

/* ─── form fields ─────────────────────────────────────────────── */
.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: 0;

  label { font-size: 12.5px; color: var(--muted); font-weight: 500; }
  .hint { font-size: 12px; color: var(--err); margin: 0; min-height: 1em; }
}
:is(.input, .select) {
  width: 100%;
  min-height: 44px;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--fg);
  font: inherit;
  font-size: 15px;
  transition: border-color 0.15s ease;

  &:hover { border-color: color-mix(in oklch, var(--fg) 30%, var(--border)); }
  &:focus { outline: 2px solid var(--accent-soft); border-color: var(--accent); }
}
.input-error { border-color: var(--err) !important; }

/* ─── trainer ─────────────────────────────────────────────────── */
.app-col { max-width: 600px; margin-inline: auto; }

.speaker-btn {
  width: 88px; height: 88px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--fg);
  display: grid; place-items: center;
  margin-inline: auto;
  transition: border-color 0.15s ease, background 0.15s ease;

  &:hover { border-color: var(--accent); color: var(--accent); }
  &:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
  &.speaking {
    border-color: var(--accent);
    color: var(--accent);
    animation: pulse 1.1s ease-out infinite;
  }
}
@keyframes pulse {
  0%   { box-shadow: 0 0 0 0 var(--accent-soft); }
  100% { box-shadow: 0 0 0 18px transparent; }
}

.skeleton {
  display: inline-block;
  width: 12ch;
  height: 1em;
  vertical-align: middle;
  border-radius: 999px;
  background: var(--border);
  animation: skeleton-pulse 1.2s ease-in-out infinite;
}
@keyframes skeleton-pulse {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.4; }
}

.answer-input {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 24px;
  letter-spacing: 0.02em;
  text-align: center;
  padding: 14px 16px;
}

.reveal-num {
  font-family: var(--font-display);
  font-size: clamp(56px, 12vw, 88px);
  font-weight: 650;
  line-height: 1;
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
  margin: 0;
  overflow-wrap: anywhere;
}

.feedback-panel { text-align: center; }
.compare {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--gap-md);
  border-top: 1px solid var(--border);
  margin-top: var(--gap-md);
  padding-top: var(--gap-md);

  .cell {
    min-width: 0;

    .val {
      font-family: var(--font-mono);
      font-variant-numeric: tabular-nums;
      font-size: 24px;
      letter-spacing: 0.01em;
      overflow-wrap: anywhere;
    }
  }
  .you .val {
    color: var(--err);
    text-decoration: line-through;
    text-decoration-thickness: 2px;
  }
  .right .val { color: var(--ok); font-weight: 600; }
  .arrow { color: var(--muted); }
}

.stats-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--gap-sm);
}
.stat-mini {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  padding: 12px 14px;

  .stat-val {
    font-family: var(--font-mono);
    font-variant-numeric: tabular-nums;
    font-size: 22px;
    font-weight: 600;
    letter-spacing: -0.01em;
  }
  .stat-key { font-size: 12px; color: var(--muted); margin-top: 2px; }
}

.settings-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: var(--gap-sm);
  align-items: start;

  @media (max-width: 560px) {
    grid-template-columns: 1fr 1fr;

    .field-lang { grid-column: 1 / -1; }
  }
}
@media (max-width: 560px) {
  .card { padding: 20px; }
}

[hidden] { display: none !important; }