/* ==========================================================================
   Wunderkind LC — student-facing platform design system.

   A serious, institutional look for high-stakes exam prep: sharp, focused,
   trustworthy. Warm paper background, near-black warm ink, one confident
   burnt-orange accent used sparingly. Instrument Serif for display headings,
   IBM Plex Sans for body, IBM Plex Mono for anything that reads as data
   (scores, timers, question numbers).

   Signature element: question numbers set large in IBM Plex Mono in the accent
   colour, flush-left, no box — like typeset numbers in a printed exam paper.
   The accent appears almost nowhere else.
   ========================================================================== */

:root {
  --color-bg:         #F7F6F2;
  --color-surface:    #FFFFFF;
  --color-border:     #D9D6CE;
  --color-text:       #1A1917;
  --color-text-sub:   #6B6760;
  --color-accent:     #C8360A;
  --color-accent-sub: #F0E8E4;
  --color-success:    #1D6A3A;
  --color-error:      #B91C1C;
  --color-timer-warn: #92400E;

  --font-display: 'Instrument Serif', Georgia, serif;
  --font-body:    'IBM Plex Sans', system-ui, sans-serif;
  --font-mono:    'IBM Plex Mono', ui-monospace, monospace;

  --space-1: 4px;
  --space-2: 8px;
  --space-3: 16px;
  --space-4: 24px;
  --space-5: 32px;
  --space-6: 48px;
  --space-7: 64px;

  --radius-sm: 3px;
  --radius-md: 6px;

  --border: 1px solid var(--color-border);
}

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

html, body {
  margin: 0;
  padding: 0;
  min-height: 100%;
}

body {
  font-family: var(--font-body);
  font-weight: 400;
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3 {
  font-family: var(--font-display);
  font-weight: 400;
  line-height: 1.1;
  color: var(--color-text);
  margin: 0;
}

/* ---------------- Layout shells ---------------- */
.page {
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}
.page__body {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  /* Vertically centered on desktop; top-aligned on small screens. */
  justify-content: center;
  padding: var(--space-5) var(--space-4);
}
@media (max-width: 640px) {
  .page__body { justify-content: flex-start; padding-top: var(--space-6); }
}

.stack {
  width: 100%;
  max-width: 440px;
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}
.stack--wide { max-width: 720px; }

/* ---------------- Brand / wordmark ---------------- */
.wordmark {
  font-family: var(--font-display);
  font-size: 34px;
  letter-spacing: 0.01em;
  color: var(--color-text);
}
.wordmark__lc { color: var(--color-accent); }
.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-text-sub);
}

/* ---------------- Surfaces ---------------- */
.card {
  background: var(--color-surface);
  border: var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-5);
}

/* ---------------- Structure line (Listening -> Reading -> Writing) ------ */
.structure {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-text-sub);
  letter-spacing: 0.02em;
}
.structure b { color: var(--color-text); font-weight: 500; }
.structure .sep { color: var(--color-border); margin: 0 var(--space-1); }

/* ---------------- Forms ---------------- */
label.field-label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}
.input {
  width: 100%;
  font-family: var(--font-body);
  font-size: 16px; /* 16px avoids iOS zoom-on-focus */
  color: var(--color-text);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
}
.input:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 1px var(--color-accent);
}
.input--code {
  font-family: var(--font-mono);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 500;
  padding: 12px 20px;
  border: 1px solid var(--color-text);
  border-radius: var(--radius-sm);
  background: var(--color-text);
  color: var(--color-bg);
  cursor: pointer;
  text-decoration: none;
}
.btn:hover:not(:disabled) { background: #000; border-color: #000; }
.btn:disabled { opacity: 1; background: var(--color-border); border-color: var(--color-border); color: var(--color-text-sub); cursor: not-allowed; }
.btn--block { width: 100%; }
.btn--accent { background: var(--color-accent); border-color: var(--color-accent); color: #fff; }
.btn--accent:hover:not(:disabled) { background: #a72d08; border-color: #a72d08; }

.form-error {
  color: var(--color-error);
  font-size: 13px;
  min-height: 18px;
}

.checkbox-row {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  font-size: 14px;
  color: var(--color-text);
  cursor: pointer;
}
.checkbox-row input[type="checkbox"] {
  width: 20px;
  height: 20px;
  margin-top: 1px;
  accent-color: var(--color-accent);
  flex-shrink: 0;
}

/* ---------------- Muted / helper text ---------------- */
.muted { color: var(--color-text-sub); }
.text-sm { font-size: 13px; }
.text-lead { font-size: 17px; color: var(--color-text-sub); }

/* ---------------- Footer ---------------- */
.page__footer {
  padding: var(--space-4);
  text-align: center;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-text-sub);
}

/* ---------------- Signature: question numbers ---------------- */
.qnum {
  font-family: var(--font-mono);
  font-size: 28px;
  font-weight: 500;
  color: var(--color-accent);
  line-height: 1;
}

/* ---------------- Timer ---------------- */
.timer {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 500;
  font-variant-numeric: tabular-nums;
  color: var(--color-text);
}
.timer.is-warning { color: var(--color-timer-warn); }

/* ---------------- Brand mark ---------------- */
.wk-logo { width: 34px; height: 34px; flex-shrink: 0; display: block; }
.wk-logo__shield { fill: var(--color-accent); }
.wk-logo__crest  { fill: #FBF9F4; }
.wk-logo__wing   {
  fill: none;
  stroke: #FBF9F4;
  stroke-width: 5;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.wordmark { display: inline-flex; align-items: center; gap: 12px; }
.page__footer { display: flex; align-items: center; justify-content: center; gap: 9px; }
.page__footer .wk-logo { width: 18px; height: 18px; }