/* ===========================================================
   Code Olympiad 2081 - Written round page
   An exam tool with a countdown clock at its heart. Built on the
   site tokens so it renders cleanly in both light and dark themes
   (toggle in the HUD bar). Token-driven only.
   =========================================================== */

:root {
  --clock-glow: drop-shadow(0 0 14px color-mix(in srgb, var(--color-phosphor) 50%, transparent));
}

html[data-theme="light"] {
  --clock-glow: drop-shadow(0 2px 10px color-mix(in srgb, var(--color-phosphor) 26%, transparent));
}

.exam {
  position: relative;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.exam::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(
    700px 480px at 50% 2%,
    color-mix(in srgb, var(--color-phosphor) 8%, transparent),
    transparent 70%
  );
  pointer-events: none;
}

/* ---------- HUD bar ---------- */
.exam-bar {
  position: sticky;
  top: 0;
  z-index: 900;
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-sm) var(--space-md);
  background: var(--color-nav-material);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--color-border-hairline);
}

.exam-bar__back {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  color: var(--color-text-tertiary);
  padding: var(--space-2xs) var(--space-xs);
  border-radius: var(--radius-xs);
  white-space: nowrap;
  transition: color var(--motion-instant) var(--ease-touch);
}

.exam-bar__back:hover {
  color: var(--color-phosphor);
}

.exam-bar__back svg {
  width: 18px;
  height: 18px;
}

.exam-bar__title {
  flex: 1;
  min-width: 0;
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-text-tertiary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.exam-bar__map {
  display: flex;
  align-items: center;
  gap: var(--space-2xs);
}

.map-dot {
  width: 7px;
  height: 7px;
  border-radius: var(--radius-full);
  background: var(--color-border-strong);
  transition: background var(--motion-instant) var(--ease-touch),
    transform var(--motion-base) var(--ease-touch);
}

.map-dot.is-visited {
  background: color-mix(in srgb, var(--color-phosphor) 45%, transparent);
}

.map-dot.is-current {
  background: var(--color-phosphor);
  transform: scale(1.35);
}

/* ---------- Stage ---------- */
.exam-main {
  flex: 1;
  width: 100%;
  max-width: 760px;
  margin-inline: auto;
  padding: var(--space-3xl) var(--space-lg) var(--space-3xl);
}

/* ---------- Countdown clock ---------- */
.clock {
  position: relative;
  width: clamp(170px, 40vw, 220px);
  margin: 0 auto var(--space-lg);
}

.clock__ring {
  display: block;
  width: 100%;
  height: auto;
  overflow: visible;
}

.clock__track {
  fill: none;
  stroke: color-mix(in srgb, var(--color-text-tertiary) 28%, transparent);
  stroke-width: 7;
}

.clock__bar {
  fill: none;
  stroke: var(--color-phosphor);
  stroke-width: 7;
  stroke-linecap: round;
  stroke-dasharray: 578.05;
  stroke-dashoffset: 0;
  filter: var(--clock-glow);
  transition: stroke-dashoffset 0.9s var(--ease-touch),
    stroke var(--motion-instant) var(--ease-touch);
}

.clock__face {
  position: absolute;
  inset: 0;
  display: grid;
  place-content: center;
  gap: var(--space-2xs);
  text-align: center;
}

.clock__label {
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-text-tertiary);
}

.clock__time {
  font-family: var(--font-display);
  font-size: clamp(2rem, 8vw, 2.9rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1;
  color: var(--color-phosphor);
  font-variant-numeric: tabular-nums;
}

/* Critical: under a minute, the clock turns red and pulses */
.clock.is-critical .clock__bar {
  stroke: var(--color-red);
  filter: drop-shadow(0 0 14px color-mix(in srgb, var(--color-red) 50%, transparent));
}

.clock.is-critical .clock__time {
  color: var(--color-red);
  animation: clockPulse 1s var(--ease-touch) infinite;
}

@keyframes clockPulse {
  0%,
  100% {
    opacity: 1;
  }

  50% {
    opacity: 0.45;
  }
}

/* ---------- Context chips under the clock ---------- */
.clock-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--space-xs);
  margin-bottom: var(--space-2xl);
}

.meta-chip {
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  color: var(--color-text-tertiary);
  border: 1px solid var(--color-border-hairline);
  padding: var(--space-2xs) var(--space-sm);
  border-radius: var(--radius-full);
  white-space: nowrap;
}

.meta-chip--accent {
  color: var(--color-phosphor);
  background: color-mix(in srgb, var(--color-phosphor) 10%, transparent);
  border-color: color-mix(in srgb, var(--color-phosphor) 45%, transparent);
}

/* ---------- Question card ---------- */
.q-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border-hairline);
  border-radius: var(--radius-lg);
  padding: var(--space-xl) var(--space-lg);
  box-shadow: var(--shadow-card);
}

.q-meta {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  margin-bottom: var(--space-md);
  flex-wrap: wrap;
}

.q-chip {
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-phosphor);
  background: color-mix(in srgb, var(--color-phosphor) 10%, transparent);
  border: 1px solid color-mix(in srgb, var(--color-phosphor) 40%, transparent);
  padding: var(--space-2xs) var(--space-sm);
  border-radius: var(--radius-full);
}

.q-tag {
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  color: var(--color-text-tertiary);
  border: 1px solid var(--color-border-hairline);
  padding: var(--space-2xs) var(--space-sm);
  border-radius: var(--radius-full);
}

.q-title {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3.5vw, 2.4rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin-bottom: var(--space-sm);
  color: var(--color-text-primary);
}

.q-desc {
  font-size: 1.0625rem;
  line-height: 1.75;
  color: var(--color-text-secondary);
}

.q-desc strong {
  color: var(--color-phosphor);
  font-weight: 700;
}

.q-img {
  margin: var(--space-xl) auto 0;
  width: 100%;
  max-width: min(80%, 540px);
  display: block;
  border: 1px solid var(--color-border-hairline);
  border-radius: var(--radius-md);
  background: var(--color-surface-2);
}

.q8 {
  display: none;
}

/* Question-change fade */
@keyframes cardJump {
  0% {
    opacity: 0;
    transform: translateY(-10px);
  }

  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

.q-card--fade {
  animation: cardJump 0.4s var(--ease-touch);
}

.exam-hint {
  margin-top: var(--space-lg);
  text-align: center;
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  color: var(--color-text-tertiary);
}

/* ---------- Docked controls ---------- */
.exam-nav {
  position: sticky;
  bottom: 0;
  z-index: 900;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background: var(--color-nav-material);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-top: 1px solid var(--color-border-hairline);
}

.exam-nav .btn {
  flex: 1;
  font-family: var(--font-mono);
  font-size: 0.875rem;
}

.exam-nav .btn:disabled {
  opacity: 0.45;
  cursor: default;
}

.exam-nav .btn svg {
  width: 16px;
  height: 16px;
}

.exam-nav__timer {
  display: flex;
  gap: var(--space-2xs);
}

.exam-nav__timer .btn {
  flex: 0 0 auto;
  padding-inline: var(--space-sm);
}

/* ---------- Responsive ---------- */
@media (max-width: 520px) {
  .exam-bar__title {
    display: none;
  }

  .clock {
    width: clamp(150px, 44vw, 200px);
  }

  .exam-nav {
    gap: var(--space-2xs);
  }

  .exam-nav__timer .btn {
    padding-inline: var(--space-xs);
  }
}