/* ==========================================================================
   Simulation module (120 traffic situations) - component styles.
   Loaded alongside the compiled assets/css/style.css (Tailwind + design-
   system components), which already supplies colors/fonts/.card, .btn-*
   and .tab-btn used throughout simulation.html. Everything here is bespoke UI
   that design system doesn't already cover: the situation grid card,
   skeleton loading, video player chrome, and the quiz/answer widgets.
   ========================================================================== */

:root {
  --sim-primary: #0b63ce;
  --sim-primary-dark: #084c9e;
  --sim-primary-light: #eaf1fc;
  --sim-accent: #ff8a00;
  --sim-accent-dark: #e67a00;
  --sim-success: #16a34a;
  --sim-success-light: #f0fdf4;
  --sim-danger: #dc2626;
  --sim-danger-light: #fef2f2;
  --sim-slate-50: #f8fafc;
  --sim-slate-100: #f1f5f9;
  --sim-slate-200: #e2e8f0;
  --sim-slate-300: #cbd5e1;
  --sim-slate-400: #94a3b8;
  --sim-slate-500: #64748b;
  --sim-slate-600: #475569;
  --sim-slate-700: #334155;
  --sim-slate-900: #0f172a;
}

/* ---------- Situations grid & cards ---------- */
.sim-grid {
  display: grid;
  grid-template-columns: repeat(1, minmax(0, 1fr));
  gap: 1rem;
}
@media (min-width: 640px) {
  .sim-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 1024px) {
  .sim-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1.25rem; }
}
@media (min-width: 1280px) {
  .sim-grid { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

.sim-card {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  padding: 1.25rem;
  border-radius: 1.75rem;
  border: 1px solid var(--sim-slate-100);
  background: #fff;
  box-shadow: 0 4px 24px rgba(15, 23, 42, 0.06);
  cursor: pointer;
  text-align: left;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}
.sim-card:hover,
.sim-card:focus-visible {
  transform: translateY(-4px);
  box-shadow: 0 20px 40px -8px rgba(11, 99, 206, 0.22);
}
.sim-card.is-done {
  border-color: rgba(22, 163, 74, 0.35);
  background: linear-gradient(180deg, var(--sim-success-light) 0%, #fff 65%);
}

.sim-card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
}
.sim-card-num {
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--sim-primary);
  background: var(--sim-primary-light);
  padding: 0.2rem 0.65rem;
  border-radius: 999px;
}
.sim-card-status {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.7rem;
  font-weight: 800;
  color: var(--sim-success);
}
.sim-card-status svg { width: 14px; height: 14px; }

.sim-card-title {
  font-size: 1rem;
  font-weight: 800;
  color: var(--sim-slate-900);
  line-height: 1.35;
}
.sim-card-chapter {
  font-size: 0.75rem;
  color: var(--sim-slate-500);
  font-weight: 600;
}
.sim-card-foot {
  margin-top: auto;
  padding-top: 0.6rem;
  border-top: 1px dashed var(--sim-slate-200);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.72rem;
  font-weight: 700;
}
.sim-card-video-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  color: var(--sim-primary);
}
.sim-card-video-tag.is-pending { color: var(--sim-slate-400); }
.sim-card-video-tag svg { width: 14px; height: 14px; }
.sim-card-score {
  color: var(--sim-slate-500);
}
.sim-card-score.is-full { color: var(--sim-success); }

/* ---------- Skeleton loading ---------- */
.sim-skeleton-card {
  border-radius: 1.75rem;
  padding: 1.25rem;
  border: 1px solid var(--sim-slate-100);
  background: #fff;
  height: 148px;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}
.sim-skeleton-line {
  border-radius: 999px;
  background: linear-gradient(90deg, var(--sim-slate-100) 25%, var(--sim-slate-200) 37%, var(--sim-slate-100) 63%);
  background-size: 400% 100%;
  animation: sim-shimmer 1.4s ease infinite;
}
.sim-skeleton-line.w-1\/3 { width: 33%; height: 0.9rem; }
.sim-skeleton-line.w-3\/4 { width: 75%; height: 1.1rem; }
.sim-skeleton-line.w-1\/2 { width: 50%; height: 0.85rem; }
.sim-skeleton-line.mt-auto { margin-top: auto; width: 100%; height: 0.85rem; }
@keyframes sim-shimmer {
  0% { background-position: 100% 50%; }
  100% { background-position: 0 50%; }
}

@media (prefers-reduced-motion: reduce) {
  .sim-skeleton-line { animation: none; }
}

/* ---------- Empty / error states ---------- */
.sim-empty-state {
  grid-column: 1 / -1;
  text-align: center;
  padding: 3rem 1rem;
  color: var(--sim-slate-500);
  font-weight: 600;
}
.sim-error-state {
  grid-column: 1 / -1;
  text-align: center;
  padding: 3rem 1.5rem;
  border-radius: 1.75rem;
  background: var(--sim-danger-light);
  color: var(--sim-danger);
  font-weight: 700;
}

/* ---------- Chapter filter pills ---------- */
.sim-chapter-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

/* ---------- Study layout ---------- */
/* video/meta/questions are placed via named grid areas (not nested wrapper
   divs) so the video's sticky containing block is the whole grid - which
   is as tall as the meta+questions column - instead of a short box that
   runs out of room to stick within almost immediately. Mobile stacks all
   three in one column; desktop puts video+meta in the left column next to
   questions spanning both rows on the right. */
.sim-study-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  grid-template-areas: "video" "meta" "questions";
  column-gap: 2rem;
  row-gap: 1.5rem;
}
@media (min-width: 1024px) {
  .sim-study-grid {
    grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
    grid-template-areas:
      "video questions"
      "meta questions";
    /* min-content (not auto) for row 1: with auto, the "questions" area
       spanning both rows contributes its full intrinsic height into row 1's
       sizing too, which pushed "meta" far down behind a large empty gap.
       min-content keeps row 1 sized to just the video's own content. */
    grid-template-rows: min-content 1fr;
    align-items: start;
  }
}

/* ---------- Video player ---------- */
/* Pinned under the site header (69px tall) while the meta/questions
   column scrolls past/underneath - applies at every breakpoint on
   purpose: on the single-column mobile layout this is what keeps the
   video visible instead of scrolling away while answering questions
   further down. */
.sim-video-sticky {
  grid-area: video;
  position: sticky;
  top: 84px;
  z-index: 10;
  background: #f8fafc;
  padding-bottom: 0.25rem;
  align-self: start;
}

.sim-video-wrap {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: 1.75rem;
  overflow: hidden;
  background: #0f172a;
  box-shadow: 0 4px 24px rgba(15, 23, 42, 0.12);
}
.sim-video {
  width: 100%;
  height: 100%;
  object-fit: contain;
  background: #000;
  display: block;
}
.sim-video.hidden,
.sim-video-placeholder.hidden {
  display: none;
}
.sim-video-placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  padding: 1.5rem;
  text-align: center;
  background: linear-gradient(180deg, #334155 0%, #1e293b 100%);
  color: #e2e8f0;
}
.sim-video-placeholder-icon {
  width: 64px;
  height: 64px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.12);
  display: flex;
  align-items: center;
  justify-content: center;
}
.sim-video-placeholder-icon svg { width: 28px; height: 28px; }
.sim-video-placeholder p {
  max-width: 22rem;
  font-size: 0.9rem;
  font-weight: 600;
  margin: 0;
}
.sim-video-placeholder .sim-video-placeholder-sub {
  font-size: 0.8rem;
  font-weight: 500;
  color: #94a3b8;
}

.sim-video-controls {
  margin-top: 0.9rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.6rem;
}
.sim-speed-field {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--sim-slate-600);
}
.sim-speed-field select {
  border: 1px solid var(--sim-slate-200);
  border-radius: 0.65rem;
  padding: 0.4rem 0.6rem;
  font-weight: 700;
  font-size: 0.8rem;
  color: var(--sim-slate-900);
  background: #fff;
  cursor: pointer;
}
.sim-icon-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  border: 1px solid var(--sim-slate-200);
  border-radius: 0.65rem;
  padding: 0.45rem 0.75rem;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--sim-slate-700);
  background: #fff;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease, background 0.2s ease;
}
.sim-icon-btn:hover { border-color: var(--sim-primary); color: var(--sim-primary); background: var(--sim-primary-light); }
.sim-icon-btn svg { width: 15px; height: 15px; }

.sim-situation-meta {
  grid-area: meta;
}
.sim-questions-col {
  grid-area: questions;
}
.sim-situation-meta h2 {
  font-size: 1.3rem;
  font-weight: 800;
  color: var(--sim-slate-900);
}
.sim-situation-meta .sim-chapter-tag {
  display: inline-flex;
  margin-top: 0.4rem;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--sim-primary);
  background: var(--sim-primary-light);
  padding: 0.3rem 0.75rem;
  border-radius: 999px;
}

/* ---------- Questions / answers ---------- */
.sim-score-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.25rem;
  border-radius: 1.25rem;
  background: var(--sim-slate-50);
  border: 1px solid var(--sim-slate-100);
  margin-bottom: 1.25rem;
}
.sim-score-panel-text {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--sim-slate-600);
}
.sim-score-panel-value {
  font-size: 1.05rem;
  font-weight: 900;
  color: var(--sim-slate-900);
}
.sim-progressbar {
  flex: 1;
  height: 10px;
  border-radius: 999px;
  background: var(--sim-slate-200);
  overflow: hidden;
  min-width: 6rem;
}
.sim-progressbar-fill {
  height: 100%;
  width: 0%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--sim-primary) 0%, var(--sim-accent) 100%);
  transition: width 0.5s ease;
}

.sim-question {
  padding: 1.1rem;
  border-radius: 1.25rem;
  border: 1px solid var(--sim-slate-100);
  background: #fff;
  box-shadow: 0 4px 24px rgba(15, 23, 42, 0.05);
  margin-bottom: 1rem;
}
.sim-question-title {
  display: flex;
  gap: 0.5rem;
  font-weight: 700;
  color: var(--sim-slate-900);
  margin-bottom: 0.85rem;
  line-height: 1.45;
}
.sim-question-title .sim-q-number {
  flex-shrink: 0;
  color: var(--sim-primary);
}

.sim-options {
  display: grid;
  gap: 0.6rem;
}
.sim-option {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  padding: 0.7rem 0.85rem;
  border-radius: 0.9rem;
  border: 1.5px solid var(--sim-slate-200);
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease;
}
.sim-option:hover { border-color: var(--sim-primary); background: var(--sim-primary-light); }
.sim-option input[type="radio"] {
  accent-color: var(--sim-primary);
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}
.sim-option-letter {
  flex-shrink: 0;
  width: 26px;
  height: 26px;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 800;
  background: var(--sim-slate-100);
  color: var(--sim-slate-600);
}
.sim-option-text {
  font-size: 0.9rem;
  color: var(--sim-slate-700);
  font-weight: 600;
  line-height: 1.4;
}
.sim-option.is-selected {
  border-color: var(--sim-primary);
  background: var(--sim-primary-light);
}
.sim-option.is-selected .sim-option-letter {
  background: var(--sim-primary);
  color: #fff;
}
.sim-question.is-graded .sim-option {
  cursor: default;
  pointer-events: none;
}
.sim-question.is-graded .sim-option.is-correct {
  border-color: var(--sim-success);
  background: var(--sim-success-light);
}
.sim-question.is-graded .sim-option.is-correct .sim-option-letter {
  background: var(--sim-success);
  color: #fff;
}
.sim-question.is-graded .sim-option.is-wrong {
  border-color: var(--sim-danger);
  background: var(--sim-danger-light);
}
.sim-question.is-graded .sim-option.is-wrong .sim-option-letter {
  background: var(--sim-danger);
  color: #fff;
}

.sim-explanation {
  margin-top: 0.85rem;
  padding: 0.85rem 1rem;
  border-radius: 0.9rem;
  font-size: 0.85rem;
  line-height: 1.5;
  font-weight: 600;
  background: var(--sim-success-light);
  color: #14532d;
  border: 1px solid rgba(22, 163, 74, 0.25);
}
.sim-explanation.is-wrong {
  background: var(--sim-danger-light);
  color: #7f1d1d;
  border-color: rgba(220, 38, 38, 0.25);
}
.sim-explanation strong { display: inline-flex; align-items: center; gap: 0.35rem; }

/* ---------- Nav bar (prev / next / back) ---------- */
.sim-nav-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-top: 1.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--sim-slate-100);
}

/* ---------- Small helpers ---------- */
.hidden { display: none !important; }