/* ============================================================
   IIHS PhD Question Bank — Stylesheet
   ============================================================ */

/* LIGHT THEME (default) */
:root {
  --bg:           #f6f4f0;
  --sidebar-bg:   #edeae4;
  --surface:      #ffffff;
  --border:       #e0dbd3;
  --accent:       #7a9e8a;
  --accent-light: #d6eadd;
  --text:         #2a2826;
  --muted:        #8c857c;
  --correct:      #6a9e78;
  --wrong:        #c47878;
  --tag-env:      #daeedd;
  --tag-env-c:    #2d6e3e;
  --tag-clim:     #d6e8f5;
  --tag-clim-c:   #2a5c80;
  --tag-urb:      #e8d9f5;
  --tag-urb-c:    #5e3a80;
  --tag-dev:      #f5e8d0;
  --tag-dev-c:    #7a5010;
  --tag-res:      #f5d9ee;
  --tag-res-c:    #7a2a60;
  --tag-pol:      #d4f0ee;
  --tag-pol-c:    #1e6060;
  --tag-part-bg:  #e8e4de;
  --tag-part-c:   #5a524a;
  --opt-correct-bg: #ddf0e3;
  --opt-correct-c:  #1e5e2e;
  --opt-wrong-bg:   #f5dede;
  --opt-wrong-c:    #7a2020;
  --theme-icon:   "☀";
}

/* DARK THEME */
[data-theme="dark"] {
  --bg:           #18161400;
  --bg:           #1c1a18;
  --sidebar-bg:   #211f1d;
  --surface:      #272422;
  --border:       #3a3530;
  --accent:       #7daa90;
  --accent-light: #243530;
  --text:         #e5e0d8;
  --muted:        #7a736a;
  --correct:      #6da882;
  --wrong:        #c47878;
  --tag-env:      #1a3522;
  --tag-env-c:    #7ecf90;
  --tag-clim:     #162838;
  --tag-clim-c:   #6db8e0;
  --tag-urb:      #281838;
  --tag-urb-c:    #c090e0;
  --tag-dev:      #352210;
  --tag-dev-c:    #d09040;
  --tag-res:      #381228;
  --tag-res-c:    #d080b0;
  --tag-pol:      #0e2c2c;
  --tag-pol-c:    #5ad0cc;
  --tag-part-bg:  #2e2a26;
  --tag-part-c:   #90887e;
  --opt-correct-bg: #1a3520;
  --opt-correct-c:  #7ecf90;
  --opt-wrong-bg:   #381818;
  --opt-wrong-c:    #e09090;
  --theme-icon:   "🌙";
}

/* ============================================================
   RESET & BASE
   ============================================================ */
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: 'DM Sans', sans-serif;
  font-size: 15px;
  line-height: 1.6;
  transition: background 0.25s, color 0.25s;
}

/* ============================================================
   HEADER
   ============================================================ */
header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 1rem 1.5rem;
  transition: background 0.25s, border-color 0.25s;
}
.header-inner {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}
.header-titles { display: flex; align-items: baseline; gap: 1rem; flex-wrap: wrap; flex: 1; }
header h1 { font-size: 1.25rem; font-weight: 600; color: var(--text); }
header p  { color: var(--muted); font-size: 0.82rem; }

/* THEME SWITCHER */
.theme-switcher {
  display: flex;
  background: var(--bg);
  border: 1.5px solid var(--border);
  border-radius: 9px;
  padding: 3px;
  gap: 2px;
  flex-shrink: 0;
  transition: border-color 0.2s, background 0.25s;
}
.theme-opt {
  background: transparent;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-size: 1rem;
  line-height: 1;
  padding: 0.25rem 0.45rem;
  transition: background 0.15s, opacity 0.15s;
  opacity: 0.35;
}
.theme-opt:hover        { opacity: 0.7; }
.theme-opt.active       { background: var(--surface); opacity: 1; box-shadow: 0 1px 3px rgba(0,0,0,0.12); }
.theme-opt:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ============================================================
   APP LAYOUT
   ============================================================ */
.app-layout {
  display: grid;
  grid-template-columns: 230px 1fr;
  min-height: calc(100vh - 57px);
}

/* ============================================================
   SIDEBAR
   ============================================================ */
aside {
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  padding: 1.25rem 1rem;
  position: sticky;
  top: 0;
  height: calc(100vh - 57px);
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  transition: background 0.25s, border-color 0.25s;
}
.sidebar-section-label {
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 0.6rem;
}

/* ============================================================
   QUIZ BOX
   ============================================================ */
.quiz-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem;
  transition: background 0.25s, border-color 0.25s;
}
.quiz-box-title { font-weight: 500; font-size: 0.88rem; color: var(--text); margin-bottom: 0.25rem; }
.quiz-box-sub   { font-size: 0.76rem; color: var(--muted); margin-bottom: 0.8rem; }

/* ============================================================
   FORM ELEMENTS
   ============================================================ */
select, input, .btn { font-family: 'DM Sans', sans-serif; }

select {
  width: 100%;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 7px;
  color: var(--text);
  padding: 0.45rem 0.7rem;
  font-size: 0.83rem;
  cursor: pointer;
  outline: none;
  margin-bottom: 0.6rem;
  transition: background 0.2s, border-color 0.2s, color 0.2s;
}
select:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

input[type="search"] {
  width: 100%;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  padding: 0.55rem 0.9rem;
  font-size: 0.85rem;
  outline: none;
  transition: background 0.2s, border-color 0.2s, color 0.2s;
}
input[type="search"]::placeholder { color: var(--muted); }
input[type="search"]:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.btn {
  padding: 0.55rem 1.3rem;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 500;
  transition: filter 0.15s, background 0.15s;
}
.btn:hover { filter: brightness(0.94); }
.btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.btn-primary   { background: var(--accent); color: #fff; width: 100%; }
.btn-secondary {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border) !important;
}

/* ============================================================
   PART FILTER PILLS
   ============================================================ */
.pill-group { display: flex; flex-direction: column; gap: 0.35rem; }
.pill {
  background: transparent;
  border: 1.5px solid var(--border);
  border-radius: 7px;
  padding: 0.4rem 0.8rem;
  font-size: 0.82rem;
  font-family: 'DM Sans', sans-serif;
  color: var(--muted);
  cursor: pointer;
  text-align: left;
  transition: all 0.15s;
}
.pill:hover             { border-color: var(--accent); color: var(--text); }
.pill.active            { background: var(--accent-light); border-color: var(--accent); color: var(--text); font-weight: 500; }
.pill:focus-visible     { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ============================================================
   MAIN CONTENT
   ============================================================ */
main { padding: 1.5rem; overflow-y: auto; }
.count-label { color: var(--muted); font-size: 0.78rem; margin-bottom: 1rem; }

/* MOBILE FILTER TOGGLE */
.filter-toggle-btn {
  display: none;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.5rem 1rem;
  font-family: 'DM Sans', sans-serif;
  font-size: 0.85rem;
  color: var(--text);
  cursor: pointer;
  margin-bottom: 1rem;
}
.filter-toggle-btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ============================================================
   CATEGORY TAGS
   ============================================================ */
.tag {
  display: inline-block;
  font-size: 0.65rem;
  font-weight: 500;
  border-radius: 4px;
  padding: 0.15rem 0.5rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-right: 0.3rem;
}
.tag-part         { background: var(--tag-part-bg); color: var(--tag-part-c); }
.tag-Environment  { background: var(--tag-env);  color: var(--tag-env-c); }
.tag-Climate      { background: var(--tag-clim); color: var(--tag-clim-c); }
.tag-Urban        { background: var(--tag-urb);  color: var(--tag-urb-c); }
.tag-Development,
.tag-Social       { background: var(--tag-dev);  color: var(--tag-dev-c); }
.tag-Research,
.tag-Statistics   { background: var(--tag-res);  color: var(--tag-res-c); }
.tag-Indian,
.tag-Governance   { background: var(--tag-pol);  color: var(--tag-pol-c); }
.tag-default      { background: var(--tag-part-bg); color: var(--muted); }

/* CATEGORY TAG STRIP */
.cat-tag-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 1rem;
}
.cat-tag-btn {
  font-family: 'DM Sans', sans-serif;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  border-radius: 5px;
  padding: 0.3rem 0.7rem;
  border: 1.5px solid transparent;
  cursor: pointer;
  transition: all 0.15s;
  opacity: 0.65;
}
.cat-tag-btn:hover  { opacity: 1; }
.cat-tag-btn.active { opacity: 1; border-color: currentColor; }
.cat-tag-btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* Inherit color from tag classes */
.cat-tag-btn.tag-part        { background: var(--tag-part-bg); color: var(--tag-part-c); }
.cat-tag-btn.tag-Environment { background: var(--tag-env);  color: var(--tag-env-c); }
.cat-tag-btn.tag-Climate     { background: var(--tag-clim); color: var(--tag-clim-c); }
.cat-tag-btn.tag-Urban       { background: var(--tag-urb);  color: var(--tag-urb-c); }
.cat-tag-btn.tag-Development,
.cat-tag-btn.tag-Social      { background: var(--tag-dev);  color: var(--tag-dev-c); }
.cat-tag-btn.tag-Research,
.cat-tag-btn.tag-Statistics  { background: var(--tag-res);  color: var(--tag-res-c); }
.cat-tag-btn.tag-Indian,
.cat-tag-btn.tag-Governance  { background: var(--tag-pol);  color: var(--tag-pol-c); }
.cat-tag-btn.tag-default     { background: var(--tag-part-bg); color: var(--muted); }
/* "All" button */
.cat-tag-btn-all { background: var(--tag-part-bg); color: var(--tag-part-c); }

/* ============================================================
   QUESTION CARDS
   ============================================================ */
.q-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  margin-bottom: 0.7rem;
  overflow: hidden;
  transition: border-color 0.2s, box-shadow 0.2s, background 0.25s;
}
.q-card:hover {
  border-color: var(--muted);
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}
.q-header { padding: 1rem 1.2rem 0.6rem; }
.q-meta   { margin-bottom: 0.45rem; }
.q-num    { color: var(--muted); font-size: 0.75rem; margin-right: 0.4rem; }
.q-text   { color: var(--text); font-size: 0.93rem; line-height: 1.65; }
.saq-badge {
  display: inline-block;
  font-size: 0.65rem;
  background: var(--tag-res);
  color: var(--tag-res-c);
  border-radius: 4px;
  padding: 0.2rem 0.6rem;
  margin-left: 0.5rem;
  vertical-align: middle;
}

/* OPTIONS */
.q-options { padding: 0 1.2rem 0.8rem; display: flex; flex-direction: column; gap: 0.4rem; }
.opt-btn {
  background: transparent;
  border: 1.5px solid var(--border);
  border-radius: 7px;
  padding: 0.55rem 0.9rem;
  text-align: left;
  color: var(--text);
  cursor: pointer;
  font-size: 0.85rem;
  font-family: 'DM Sans', sans-serif;
  transition: all 0.15s;
  width: 100%;
}
.opt-btn:hover:not(.disabled) { border-color: var(--accent); background: var(--accent-light); }
.opt-btn:focus-visible         { outline: 2px solid var(--accent); outline-offset: 2px; }
.opt-btn.selected              { background: var(--accent-light); border-color: var(--accent); }
.opt-btn.correct               { background: var(--opt-correct-bg); border-color: var(--correct); color: var(--opt-correct-c); }
.opt-btn.wrong                 { background: var(--opt-wrong-bg);   border-color: var(--wrong);   color: var(--opt-wrong-c); }
.opt-btn.disabled              { cursor: default; }
.opt-letter { opacity: 0.45; margin-right: 0.5rem; }

.reveal-row { padding: 0 1.2rem 0.9rem; display: flex; gap: 0.5rem; align-items: center; }
.reveal-btn {
  font-size: 0.72rem;
  background: none;
  border: 1px solid var(--border);
  border-radius: 5px;
  color: var(--muted);
  cursor: pointer;
  padding: 0.28rem 0.7rem;
  font-family: inherit;
  transition: all 0.15s;
}
.reveal-btn:hover        { border-color: var(--accent); color: var(--accent); }
.reveal-btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.revealed-text { font-size: 0.72rem; color: var(--correct); }

/* SAQ CARD */
.saq-body { padding: 0.2rem 1.2rem 0.9rem; }
.saq-hint {
  font-size: 0.78rem;
  color: var(--muted);
  font-style: italic;
  border-left: 2px solid var(--border);
  padding-left: 0.7rem;
  margin-top: 0.4rem;
}

/* ============================================================
   QUIZ SCREEN
   ============================================================ */
#quiz-screen         { display: none; min-height: 100vh; background: var(--bg); }
#quiz-screen.active  { display: block; }
#browse-screen.hidden { display: none; }

.quiz-wrap        { max-width: 680px; margin: 0 auto; padding: 1.5rem; }
.quiz-topbar      { display: flex; justify-content: space-between; align-items: center; margin-bottom: 1rem; }
.quiz-progress-bar {
  height: 4px;
  background: var(--border);
  border-radius: 2px;
  margin-bottom: 1.5rem;
}
.quiz-progress-fill { height: 100%; background: var(--accent); border-radius: 2px; transition: width 0.3s; }
.quiz-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
  margin-bottom: 1rem;
  transition: background 0.25s, border-color 0.25s;
}
.quiz-cat { font-size: 0.68rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 0.7rem; }
.quiz-q   { font-size: 1.02rem; color: var(--text); line-height: 1.7; margin-bottom: 1.3rem; }
.quiz-opts { display: flex; flex-direction: column; gap: 0.55rem; }

.quiz-opt {
  background: var(--bg);
  border: 1.5px solid var(--border);
  border-radius: 8px;
  padding: 0.7rem 1rem;
  text-align: left;
  color: var(--text);
  cursor: pointer;
  font-size: 0.88rem;
  font-family: inherit;
  transition: all 0.15s;
  width: 100%;
}
.quiz-opt:hover:not(.qdisabled) { border-color: var(--accent); background: var(--accent-light); }
.quiz-opt:focus-visible          { outline: 2px solid var(--accent); outline-offset: 2px; }
.quiz-opt.qcorrect               { background: var(--opt-correct-bg); border-color: var(--correct); color: var(--opt-correct-c); }
.quiz-opt.qwrong                 { background: var(--opt-wrong-bg);   border-color: var(--wrong);   color: var(--opt-wrong-c); }
.quiz-opt.qdisabled              { cursor: default; }

.quiz-next-row { display: flex; justify-content: flex-end; }

/* ============================================================
   RESULTS
   ============================================================ */
.results-wrap   { max-width: 680px; margin: 0 auto; padding: 2rem 1.5rem; text-align: center; }
.results-score  { font-size: 3.5rem; font-weight: 600; margin: 1rem 0 0.3rem; }
.results-pct    { font-size: 1rem; color: var(--muted); margin-bottom: 2rem; }
.results-actions { display: flex; gap: 0.8rem; justify-content: center; flex-wrap: wrap; margin-bottom: 2rem; }

.result-item {
  background: var(--surface);
  border-radius: 8px;
  padding: 0.7rem 1rem;
  margin-bottom: 0.5rem;
  text-align: left;
  border-left: 3px solid;
  transition: background 0.25s;
}
.result-item.ok  { border-color: var(--correct); }
.result-item.bad { border-color: var(--wrong); }
.result-item-q   { font-size: 0.82rem; color: var(--text); margin-bottom: 0.25rem; }
.result-item-ans { font-size: 0.77rem; color: var(--correct); }
.result-tag      { font-size: 0.68rem; color: var(--muted); margin-bottom: 0.2rem; }

/* ============================================================
   MISC
   ============================================================ */
.empty  { text-align: center; padding: 3rem; color: var(--muted); }
footer  { text-align: center; padding: 1.25rem; font-size: 0.72rem; color: var(--muted); border-top: 1px solid var(--border); margin-top: 1rem; }

/* ============================================================
   MOBILE
   ============================================================ */
@media (max-width: 720px) {
  .app-layout { grid-template-columns: 1fr; }
  aside {
    display: none;
    position: static;
    height: auto;
    border-right: none;
    border-bottom: 1px solid var(--border);
  }
  aside.open         { display: flex; }
  .filter-toggle-btn { display: block; }
  header h1          { font-size: 1.1rem; }
  .results-actions   { flex-direction: column; align-items: center; }
}