/* =============================================================
   CaseCraft — Editorial / Case-Journal aesthetic
   Cream paper · Deep ink · Burnt-ochre accent
   ============================================================= */

:root {
  /* Palette */
  --paper: #f3ecde;
  --paper-deep: #ebe2d0;
  --paper-edge: #ddd2bc;
  --ink: #1a1f2e;
  --ink-soft: #3a4257;
  --ink-mute: #6b7184;
  --rule: #c9bea4;
  --rule-soft: #d8cdb4;

  --accent: #a8743b;          /* burnt ochre */
  --accent-deep: #7e5226;
  --accent-soft: #d8a76c;
  --accent-tint: rgba(168, 116, 59, 0.08);

  --easy: #5a7a4a;
  --medium: #a8743b;
  --hard: #b3593a;
  --expert: #6b3a4a;

  --mastered: #5a7a4a;

  /* Type */
  --display: "Fraunces", Georgia, serif;
  --body: "Newsreader", "Iowan Old Style", Georgia, serif;
  --mono: "JetBrains Mono", ui-monospace, monospace;

  /* Spacing */
  --max-width: 1100px;
  --reading-width: 720px;

  /* Shadows */
  --shadow-paper: 0 1px 0 rgba(26, 31, 46, 0.04), 0 4px 20px rgba(26, 31, 46, 0.04);
  --shadow-elev: 0 2px 0 rgba(26, 31, 46, 0.06), 0 12px 40px rgba(26, 31, 46, 0.08);
}

/* =============================================================
   Reset & base
   ============================================================= */
* { box-sizing: border-box; }
*::selection { background: var(--accent); color: var(--paper); }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--body);
  font-size: 17px;
  line-height: 1.55;
  font-feature-settings: "kern", "liga", "onum";
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
}

/* paper grain — very subtle, layered behind everything */
.paper-grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  opacity: 0.4;
  background-image:
    radial-gradient(circle at 20% 50%, rgba(168, 116, 59, 0.03) 0%, transparent 40%),
    radial-gradient(circle at 80% 30%, rgba(26, 31, 46, 0.025) 0%, transparent 40%),
    url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='200' height='200'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/><feColorMatrix values='0 0 0 0 0.1 0 0 0 0 0.1 0 0 0 0 0.18 0 0 0 0.06 0'/></filter><rect width='200' height='200' filter='url(%23n)'/></svg>");
}

body > * { position: relative; z-index: 2; }

/* =============================================================
   Masthead (newspaper-style header)
   ============================================================= */
.masthead {
  border-bottom: 2px solid var(--ink);
  padding: 48px 24px 32px;
  background: linear-gradient(to bottom, var(--paper-deep), var(--paper));
}

.masthead-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.masthead-top {
  display: flex;
  justify-content: space-between;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-mute);
  padding-bottom: 16px;
  border-bottom: 1px solid var(--rule);
  margin-bottom: 28px;
}

.masthead-title {
  font-family: var(--display);
  font-weight: 700;
  font-size: clamp(56px, 9vw, 120px);
  line-height: 0.92;
  letter-spacing: -0.04em;
  margin: 0 0 18px;
  font-variation-settings: "SOFT" 30, "WONK" 1, "opsz" 144;
  color: var(--ink);
}

.title-mark {
  color: var(--accent);
  font-weight: 400;
  font-style: italic;
  font-size: 0.65em;
  vertical-align: 0.15em;
  margin-right: 0.05em;
  letter-spacing: 0;
}

.masthead-tagline {
  font-family: var(--body);
  font-size: clamp(17px, 2.2vw, 21px);
  font-style: italic;
  font-weight: 400;
  color: var(--ink-soft);
  max-width: 720px;
  line-height: 1.45;
  margin: 0 0 36px;
  font-feature-settings: "kern", "liga";
}

.masthead-tagline em { font-style: italic; }

.masthead-stats {
  display: flex;
  gap: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--rule);
  flex-wrap: wrap;
}

.stat {
  display: flex;
  flex-direction: column;
}

.stat-num {
  font-family: var(--display);
  font-size: 36px;
  font-weight: 600;
  line-height: 1;
  color: var(--ink);
  font-variation-settings: "opsz" 144;
}

.stat-label {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-mute);
  margin-top: 6px;
}

/* =============================================================
   How-to-read banner
   ============================================================= */
.rule-nav {
  background: var(--ink);
  color: var(--paper);
  padding: 18px 24px;
}

.rule-nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  gap: 24px;
  align-items: baseline;
  flex-wrap: wrap;
}

.rule-nav-label {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent-soft);
  flex-shrink: 0;
}

.rule-nav-text {
  font-family: var(--body);
  font-size: 15px;
  line-height: 1.5;
  color: var(--paper);
  flex: 1;
  min-width: 280px;
}

.rule-nav-text em {
  font-style: italic;
  color: var(--accent-soft);
}

/* =============================================================
   Filter bar
   ============================================================= */
.filters {
  border-bottom: 1px solid var(--rule);
  padding: 24px;
  background: var(--paper-deep);
}

.filters-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  align-items: start;
}

.filter-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.filter-label {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-mute);
}

.chip-row {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.chip {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  padding: 6px 12px;
  border: 1px solid var(--rule);
  background: var(--paper);
  color: var(--ink-soft);
  cursor: pointer;
  border-radius: 0;
  transition: all 0.15s ease;
  font-weight: 500;
  white-space: nowrap;
}

.chip:hover {
  border-color: var(--ink);
  color: var(--ink);
}

.chip.active {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--paper);
}

.chip-action {
  background: transparent;
  border-style: dashed;
}

.chip-action.active {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--paper);
  border-style: solid;
}

.filter-search input {
  font-family: var(--body);
  font-size: 16px;
  padding: 10px 14px;
  border: 1px solid var(--rule);
  background: var(--paper);
  color: var(--ink);
  border-radius: 0;
  width: 100%;
  outline: none;
  transition: border-color 0.15s;
}

.filter-search input:focus {
  border-color: var(--ink);
}

.filter-search input::placeholder {
  color: var(--ink-mute);
  font-style: italic;
}

/* =============================================================
   Question list
   ============================================================= */
.question-list {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 32px 24px 64px;
}

.question-card {
  background: var(--paper);
  border: 1px solid var(--rule);
  margin-bottom: 18px;
  transition: border-color 0.2s, box-shadow 0.2s;
  position: relative;
  scroll-margin-top: 24px;
}

.question-card:hover:not(.expanded) {
  border-color: var(--ink-mute);
  box-shadow: var(--shadow-paper);
}

.question-card.expanded {
  border-color: var(--ink);
  box-shadow: var(--shadow-elev);
}

.question-card.mastered::before {
  content: "";
  position: absolute;
  left: -1px;
  top: -1px;
  bottom: -1px;
  width: 4px;
  background: var(--mastered);
}

.question-card.practiced:not(.mastered)::before {
  content: "";
  position: absolute;
  left: -1px;
  top: -1px;
  bottom: -1px;
  width: 4px;
  background: var(--accent);
}

.q-header {
  padding: 22px 26px;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 20px;
  align-items: start;
}

.q-meta {
  display: flex;
  gap: 10px;
  align-items: center;
  margin-bottom: 10px;
  flex-wrap: wrap;
}

.q-num {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--ink-mute);
  letter-spacing: 0.1em;
}

.q-difficulty {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  padding: 3px 8px;
  border: 1px solid currentColor;
  font-weight: 500;
}

.q-difficulty[data-difficulty="Easy"] { color: var(--easy); }
.q-difficulty[data-difficulty="Medium"] { color: var(--medium); }
.q-difficulty[data-difficulty="Hard"] { color: var(--hard); }
.q-difficulty[data-difficulty="Expert"] { color: var(--expert); }

.q-category {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-mute);
}

.q-prompt {
  font-family: var(--display);
  font-weight: 500;
  font-size: clamp(20px, 2.4vw, 26px);
  line-height: 1.25;
  letter-spacing: -0.015em;
  color: var(--ink);
  margin: 0 0 12px;
  font-variation-settings: "opsz" 144;
}

.q-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.q-tag {
  font-family: var(--mono);
  font-size: 10px;
  color: var(--ink-mute);
  letter-spacing: 0.04em;
}

.q-tag::before { content: "#"; color: var(--accent); }

.q-controls {
  display: flex;
  flex-direction: column;
  gap: 8px;
  align-items: stretch;
  min-width: 150px;
}

.btn-reveal {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 10px 16px;
  background: var(--ink);
  color: var(--paper);
  border: 1px solid var(--ink);
  cursor: pointer;
  font-weight: 500;
  transition: background 0.15s, border-color 0.15s;
}

.btn-reveal:hover {
  background: var(--accent);
  border-color: var(--accent);
}

.expanded .btn-reveal {
  background: var(--paper);
  color: var(--ink);
}

.expanded .btn-reveal:hover {
  background: var(--paper-deep);
}

.btn-mark {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  padding: 6px 10px;
  background: transparent;
  color: var(--ink-soft);
  border: 1px dashed var(--rule);
  cursor: pointer;
  transition: all 0.15s;
}

.btn-mark:hover {
  border-color: var(--ink-soft);
  color: var(--ink);
  border-style: solid;
}

.btn-mark.active-practiced {
  background: var(--accent-tint);
  border-color: var(--accent);
  color: var(--accent-deep);
  border-style: solid;
}

.btn-mark.active-mastered {
  background: rgba(90, 122, 74, 0.1);
  border-color: var(--mastered);
  color: var(--mastered);
  border-style: solid;
}

/* =============================================================
   Analysis (revealed content)
   ============================================================= */
.q-analysis {
  border-top: 1px solid var(--rule);
  padding: 32px 26px 36px;
  background:
    linear-gradient(to bottom, var(--paper-deep), var(--paper));
  display: none;
  animation: revealUp 0.35s cubic-bezier(0.2, 0.8, 0.2, 1);
}

@keyframes revealUp {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: translateY(0); }
}

.q-analysis.show { display: block; }

.q-analysis-inner {
  max-width: var(--reading-width);
}

.analysis-header {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  border-bottom: 1px solid var(--accent);
  padding-bottom: 8px;
  margin-bottom: 24px;
  font-weight: 500;
}

.analysis-section {
  margin-bottom: 26px;
}

.analysis-section:last-child { margin-bottom: 0; }

.analysis-section h4 {
  font-family: var(--display);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.005em;
  color: var(--ink);
  margin: 0 0 8px;
  font-variation-settings: "opsz" 24;
}

.analysis-section h4::before {
  content: "▸";
  color: var(--accent);
  margin-right: 8px;
  font-weight: 400;
  font-size: 0.85em;
  display: inline-block;
  transform: translateY(-1px);
}

.analysis-section .body-text {
  font-family: var(--body);
  font-size: 16.5px;
  line-height: 1.65;
  color: var(--ink-soft);
  font-feature-settings: "kern", "liga", "onum";
}

.analysis-section .body-text b,
.analysis-section .body-text strong {
  color: var(--ink);
  font-weight: 600;
}

.analysis-section .body-text i,
.analysis-section .body-text em {
  font-style: italic;
  color: var(--ink);
}

.analysis-section .body-text br {
  display: block;
  content: "";
  margin-top: 6px;
}

/* =============================================================
   Empty state
   ============================================================= */
.empty-state {
  max-width: var(--reading-width);
  margin: 64px auto;
  text-align: center;
  padding: 48px 24px;
  border: 1px dashed var(--rule);
  background: var(--paper-deep);
}

.empty-mark {
  font-family: var(--display);
  font-size: 64px;
  color: var(--accent);
  margin: 0 0 12px;
  font-weight: 300;
}

.empty-state p {
  font-family: var(--body);
  color: var(--ink-soft);
  font-size: 17px;
  margin: 0 0 16px;
  font-style: italic;
}

/* =============================================================
   Colophon (footer)
   ============================================================= */
.colophon {
  border-top: 2px solid var(--ink);
  background: var(--paper-deep);
  padding: 48px 24px 32px;
  margin-top: 48px;
}

.colophon-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 36px;
}

.colophon-block h4 {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0 0 10px;
  font-weight: 500;
}

.colophon-block p {
  font-family: var(--body);
  font-size: 14px;
  line-height: 1.55;
  color: var(--ink-soft);
  margin: 0 0 8px;
}

.colophon-block code {
  font-family: var(--mono);
  font-size: 12px;
  background: var(--paper);
  padding: 2px 6px;
  border: 1px solid var(--rule);
  color: var(--accent-deep);
}

.colophon-block a {
  color: var(--accent-deep);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.colophon-block a:hover { color: var(--accent); }

.colophon-bottom {
  grid-column: 1 / -1;
  margin-top: 24px;
  padding-top: 24px;
  border-top: 1px solid var(--rule);
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-mute);
}

.colophon-rule { color: var(--accent); }

/* =============================================================
   Responsive
   ============================================================= */
@media (max-width: 720px) {
  .masthead { padding: 36px 20px 24px; }
  .masthead-stats { gap: 24px; }
  .stat-num { font-size: 28px; }
  .filters { padding: 20px; }
  .question-list { padding: 24px 16px 48px; }
  .q-header {
    grid-template-columns: 1fr;
    padding: 20px;
  }
  .q-controls {
    flex-direction: row;
    flex-wrap: wrap;
    min-width: 0;
  }
  .q-controls > * { flex: 1; min-width: 100px; }
  .q-analysis { padding: 24px 20px 28px; }
  .analysis-section .body-text { font-size: 16px; }
  .colophon { padding: 36px 20px 24px; }
}

@media (max-width: 480px) {
  body { font-size: 16px; }
  .q-prompt { font-size: 19px; }
  .masthead-tagline { font-size: 16px; }
  .rule-nav-text { font-size: 14px; }
}

/* Print: clean, readable */
@media print {
  .paper-grain, .filters, .rule-nav, .q-controls, .colophon { display: none; }
  .question-card { break-inside: avoid; border: 1px solid #999; margin-bottom: 12px; }
  .q-analysis { display: block !important; }
  body { background: white; color: black; }
}