/* ── Reset & Root ──────────────────────────────────────────────────────────── */
:root {
  --bg:         #F2EBDC;
  --bg-deep:    #E8DFCB;
  --card:       #FBF7EC;
  --card-front: #FFFCF3;
  --ink:        #1C1814;
  --ink-soft:   #4A413A;
  --ink-mute:   #7A6F65;
  --rule:       #C9BFA8;
  --rule-soft:  #DDD3BC;
  --accent:     #8B2818;
  --accent-dark:#5E1A0F;
  --gold:       #A4853A;
  --green:      #4A6B3A;
  --amber:      #B8702F;
  --serif: 'Fraunces', Georgia, serif;
  --sans:  'DM Sans', system-ui, sans-serif;
  --mono:  'JetBrains Mono', monospace;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html, body { height: 100%; }

body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--ink);
  min-height: 100vh;
  background-image:
    radial-gradient(at 20% 10%, rgba(139,40,24,0.04) 0%, transparent 50%),
    radial-gradient(at 85% 90%, rgba(164,133,58,0.05) 0%, transparent 50%);
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed; inset: 0;
  background-image: repeating-linear-gradient(
    0deg,
    rgba(28,24,20,0.012) 0px, rgba(28,24,20,0.012) 1px,
    transparent 1px, transparent 3px
  );
  pointer-events: none;
  z-index: 0;
}

/* ── Flash messages ────────────────────────────────────────────────────────── */
.flash {
  position: fixed; top: 0; left: 0; right: 0;
  padding: 10px 20px;
  font-family: var(--sans); font-size: 13px; font-weight: 500;
  text-align: center; z-index: 1000;
  animation: flashIn 0.2s ease;
}
.flash-notice { background: var(--green); color: #fff; }
.flash-alert  { background: var(--accent); color: #fff; }
@keyframes flashIn { from { transform: translateY(-100%); } to { transform: translateY(0); } }

/* ── App wrapper ───────────────────────────────────────────────────────────── */
.app {
  max-width: 980px;
  margin: 0 auto;
  padding: 36px 28px 60px;
  position: relative; z-index: 1;
}

/* ── Header ────────────────────────────────────────────────────────────────── */
header {
  display: flex; align-items: flex-end; justify-content: space-between;
  border-bottom: 1px solid var(--rule);
  padding-bottom: 18px; margin-bottom: 24px;
  gap: 20px; flex-wrap: wrap;
}
.brand { display: flex; flex-direction: column; gap: 4px; }
.brand .eyebrow {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--accent); font-weight: 500;
}
.brand h1 {
  font-family: var(--serif); font-weight: 600; font-style: italic;
  font-size: clamp(28px, 4.5vw, 42px); letter-spacing: -0.02em; line-height: 1; color: var(--ink);
}
.brand h1 .amp { color: var(--accent); font-style: italic; }
.brand .sub { font-family: var(--serif); font-size: 14px; color: var(--ink-mute); margin-top: 6px; font-style: italic; }

/* ── Stats row ─────────────────────────────────────────────────────────────── */
.stats {
  display: flex; gap: 18px;
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.05em;
  text-transform: uppercase; color: var(--ink-mute);
}
.stats .stat { display: flex; flex-direction: column; align-items: flex-end; gap: 2px; }
.stats .stat .n {
  font-family: var(--serif); font-size: 22px; color: var(--ink);
  font-weight: 600; letter-spacing: -0.02em;
}
.stats .stat.known   .n { color: var(--green); }
.stats .stat.learning .n { color: var(--amber); }
.stats .stat.again   .n { color: var(--accent); }
.stats .stat.due     .n { color: var(--gold); }

/* ── Header actions (logout link) ──────────────────────────────────────────── */
.header-meta {
  display: flex; align-items: center; gap: 16px;
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--ink-mute);
}
.header-meta a {
  color: var(--ink-mute); text-decoration: none;
  border-bottom: 1px solid var(--rule-soft);
  padding-bottom: 1px; transition: color 0.15s;
}
.header-meta a:hover { color: var(--accent); border-color: var(--accent); }

/* ── Filter panel ──────────────────────────────────────────────────────────── */
.filters {
  background: var(--bg-deep); border: 1px solid var(--rule);
  border-radius: 4px; padding: 16px 18px; margin-bottom: 22px;
}
.filter-row {
  display: flex; flex-wrap: wrap; align-items: center;
  gap: 10px; margin-bottom: 10px;
}
.filter-row:last-child { margin-bottom: 0; }
.filter-label {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.15em;
  text-transform: uppercase; color: var(--ink-mute);
  margin-right: 4px; min-width: 56px;
}
.filter-actions {
  display: flex; align-items: center; justify-content: space-between;
  margin-top: 12px; padding-top: 12px; border-top: 1px solid var(--rule-soft);
}
.filter-status {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.08em;
  color: var(--ink-mute); text-transform: uppercase;
}

/* ── Chips ─────────────────────────────────────────────────────────────────── */
.chip {
  font-family: var(--sans); font-size: 12px; font-weight: 500;
  padding: 5px 11px; background: var(--card-front); border: 1px solid var(--rule);
  border-radius: 999px; color: var(--ink-soft); cursor: pointer;
  transition: all 0.15s ease; white-space: nowrap;
  display: inline-flex; align-items: center; gap: 4px;
  text-decoration: none; /* for <a> chips */
}
.chip:hover  { border-color: var(--ink-soft); color: var(--ink); }
.chip.active { background: var(--ink); color: var(--bg); border-color: var(--ink); }
.chip .ct {
  font-family: var(--mono); font-size: 10px; opacity: 0.7; margin-left: 2px;
}

/* ── Card stage ────────────────────────────────────────────────────────────── */
.card-stage { perspective: 1200px; margin-bottom: 24px; }

.card {
  position: relative; width: 100%;
  min-height: 340px;
  transform-style: preserve-3d;
  transition: transform 0.55s cubic-bezier(0.4,0,0.2,1);
  cursor: pointer;
  border-radius: 6px;
}
.card.flipped { transform: rotateY(180deg); }

.face {
  position: absolute; inset: 0;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  border-radius: 6px;
  padding: 32px 36px;
  display: flex; flex-direction: column;
  border: 1px solid var(--rule);
  box-shadow: 0 2px 16px -8px rgba(28,24,20,0.12), 0 1px 4px -2px rgba(28,24,20,0.08);
}
.face.front {
  background: var(--card-front);
}
.face.back {
  background: var(--card);
  transform: rotateY(180deg);
}

/* Card meta row */
.card-meta {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 20px;
}
.meta-left { display: flex; gap: 8px; align-items: center; }

.source-tag {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--accent);
  border: 1px solid rgba(139,40,24,0.25); border-radius: 3px;
  padding: 2px 7px; background: rgba(139,40,24,0.04);
}
.theme-tag {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--ink-mute);
  border: 1px solid var(--rule-soft); border-radius: 3px;
  padding: 2px 7px; background: transparent;
}
.counter {
  font-family: var(--mono); font-size: 12px; color: var(--ink-mute); letter-spacing: 0.05em;
}
.counter .now { color: var(--ink); font-weight: 500; }

/* Q&A content */
.qa-label {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--ink-mute); margin-bottom: 12px;
}
.qa-text {
  font-family: var(--serif); font-size: clamp(16px, 2.2vw, 20px);
  line-height: 1.6; color: var(--ink); flex: 1;
}
.qa-text strong { color: var(--accent-dark); }
.qa-text em     { color: var(--ink-soft); font-style: italic; }

.hint {
  margin-top: 20px;
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--ink-mute); opacity: 0.7;
}
.hint kbd {
  display: inline-block; padding: 1px 5px; border: 1px solid var(--rule);
  border-radius: 3px; font-family: var(--mono); font-size: 9px;
  background: var(--bg-deep); color: var(--ink-soft);
}

/* Empty state */
.empty {
  text-align: center; padding: 60px 20px;
  font-family: var(--serif); font-size: 18px; color: var(--ink-mute);
  font-style: italic; line-height: 1.7;
}

/* ── Progress bar ──────────────────────────────────────────────────────────── */
.progress-bar {
  height: 2px; background: var(--rule-soft);
  border-radius: 2px; overflow: hidden; margin: 18px 0 0;
}
.progress-fill {
  height: 100%; background: var(--accent);
  transition: width 0.4s ease;
}

/* ── Controls (rating buttons) ─────────────────────────────────────────────── */
.controls {
  display: flex; gap: 10px; margin-bottom: 16px; flex-wrap: wrap;
}
.rate-btn {
  flex: 1; min-width: 80px;
  display: flex; flex-direction: column; align-items: center; gap: 3px;
  padding: 10px 14px;
  background: var(--card-front); border: 1px solid var(--rule);
  border-radius: 4px; cursor: pointer;
  transition: all 0.15s ease; font-family: var(--sans);
}
.rate-btn .label { font-size: 13px; font-weight: 500; color: var(--ink-soft); }
.rate-btn .key   { font-family: var(--mono); font-size: 9px; opacity: 0.5; letter-spacing: 0.1em; }
.rate-btn:hover  { transform: translateY(-1px); box-shadow: 0 4px 12px -6px rgba(28,24,20,0.2); }
.rate-btn.again:not(:disabled):hover { background: var(--accent); border-color: var(--accent); }
.rate-btn.again:not(:disabled):hover .label,
.rate-btn.again:not(:disabled):hover .key { color: white; }
.rate-btn.hard:not(:disabled):hover  { background: var(--amber); border-color: var(--amber); }
.rate-btn.hard:not(:disabled):hover .label,
.rate-btn.hard:not(:disabled):hover .key { color: white; }
.rate-btn.good:not(:disabled):hover  { background: var(--green); border-color: var(--green); }
.rate-btn.good:not(:disabled):hover .label,
.rate-btn.good:not(:disabled):hover .key { color: white; }
.rate-btn.easy:not(:disabled):hover  { background: var(--gold); border-color: var(--gold); }
.rate-btn.easy:not(:disabled):hover .label,
.rate-btn.easy:not(:disabled):hover .key { color: white; }
.rate-btn:disabled { opacity: 0.38; cursor: not-allowed; transform: none !important; }

/* ── Nav buttons ───────────────────────────────────────────────────────────── */
.nav {
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
}
.nav-actions { display: flex; gap: 8px; }

.nav-btn {
  font-family: var(--sans); font-size: 13px; font-weight: 500;
  padding: 8px 16px; background: transparent;
  border: 1px solid var(--rule); border-radius: 4px;
  color: var(--ink-soft); cursor: pointer;
  transition: all 0.15s ease; display: inline-flex; align-items: center; gap: 6px;
}
.nav-btn:hover { background: var(--bg-deep); border-color: var(--ink-soft); color: var(--ink); }
.nav-btn.danger:hover { background: rgba(139,40,24,0.06); border-color: var(--accent); color: var(--accent); }
.nav-btn .arr { font-size: 16px; line-height: 1; }

/* ── Footer ────────────────────────────────────────────────────────────────── */
footer {
  margin-top: 48px; padding-top: 18px;
  border-top: 1px solid var(--rule-soft);
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 12px;
}
footer .foot-text {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--ink-mute);
}
footer .dot { margin: 0 6px; }

/* ── Auth page ─────────────────────────────────────────────────────────────── */
.auth-wrap {
  min-height: 100vh; display: flex; align-items: center; justify-content: center;
  padding: 40px 20px; position: relative; z-index: 1;
}
.auth-card {
  width: 100%; max-width: 400px;
  background: var(--card-front); border: 1px solid var(--rule);
  border-radius: 6px; padding: 40px 36px;
  box-shadow: 0 4px 32px -12px rgba(28,24,20,0.15);
}
.auth-brand { text-align: center; margin-bottom: 32px; }
.auth-brand .eyebrow {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--accent); font-weight: 500; margin-bottom: 8px;
}
.auth-brand h1 {
  font-family: var(--serif); font-weight: 600; font-style: italic;
  font-size: 28px; letter-spacing: -0.02em; line-height: 1.1; color: var(--ink);
}
.auth-brand .amp { color: var(--accent); }
.auth-brand .sub {
  font-family: var(--serif); font-size: 13px; color: var(--ink-mute);
  margin-top: 6px; font-style: italic;
}

.auth-form { display: flex; flex-direction: column; gap: 16px; }
.field { display: flex; flex-direction: column; gap: 6px; }
.field label {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.15em;
  text-transform: uppercase; color: var(--ink-mute);
}
.field input[type="text"],
.field input[type="password"] {
  padding: 10px 12px; background: var(--bg);
  border: 1px solid var(--rule); border-radius: 4px;
  font-family: var(--sans); font-size: 14px; color: var(--ink);
  outline: none; transition: border-color 0.15s;
}
.field input:focus { border-color: var(--accent); }

.btn-primary {
  margin-top: 8px; padding: 11px 20px;
  background: var(--ink); color: var(--bg);
  border: none; border-radius: 4px;
  font-family: var(--sans); font-size: 14px; font-weight: 600;
  cursor: pointer; transition: background 0.15s;
  letter-spacing: 0.02em;
}
.btn-primary:hover { background: var(--accent); }

.auth-hint {
  margin-top: 20px; text-align: center;
  font-family: var(--mono); font-size: 11px; color: var(--ink-mute);
}
.auth-hint .mono {
  background: var(--bg-deep); padding: 2px 6px;
  border-radius: 3px; border: 1px solid var(--rule-soft);
  color: var(--ink-soft);
}

/* ── Responsive ────────────────────────────────────────────────────────────── */
@media (max-width: 640px) {
  .app { padding: 20px 16px 40px; }
  .stats { font-size: 10px; gap: 14px; }
  .stats .stat .n { font-size: 18px; }
  .filter-label { min-width: auto; width: 100%; }
  .face { padding: 20px 18px; }
  .qa-text { font-size: 15px; }
  .controls { gap: 6px; }
  .rate-btn { padding: 8px 10px; min-width: 60px; }
  .nav-btn { padding: 7px 12px; font-size: 12px; }
}

/* ── Mode toggle buttons ───────────────────────────────────────────────────── */
.mode-btn {
  display: inline-flex; flex-direction: column; align-items: center;
  gap: 2px; padding: 10px 20px; min-width: 120px;
  background: var(--card-front); border: 1px solid var(--rule);
  border-radius: 4px; cursor: pointer; transition: all 0.15s ease;
  font-family: var(--sans);
}
.mode-btn:hover { border-color: var(--ink-soft); background: var(--bg-deep); }
.mode-btn.active {
  background: var(--ink); border-color: var(--ink); color: var(--bg);
}
.mode-btn .mode-icon { font-size: 18px; line-height: 1; }
.mode-btn .mode-name {
  font-size: 13px; font-weight: 600; letter-spacing: 0.01em;
}
.mode-btn .mode-desc {
  font-family: var(--mono); font-size: 9px; letter-spacing: 0.08em;
  text-transform: uppercase; opacity: 0.6;
}
.mode-btn.active .mode-desc { opacity: 0.7; }

/* ── Status badge on card ──────────────────────────────────────────────────── */
.status-badge {
  font-family: var(--mono); font-size: 9px; letter-spacing: 0.1em;
  text-transform: uppercase; padding: 2px 6px; border-radius: 3px;
  border: 1px solid; font-weight: 500;
}
.status-badge.status-again { color: var(--accent); border-color: rgba(139,40,24,0.3); background: rgba(139,40,24,0.06); }
.status-badge.status-hard  { color: var(--amber);  border-color: rgba(184,112,47,0.3); background: rgba(184,112,47,0.06); }
.status-badge.status-good  { color: var(--green);  border-color: rgba(74,107,58,0.3);  background: rgba(74,107,58,0.06); }
.status-badge.status-easy  { color: var(--gold);   border-color: rgba(164,133,58,0.3); background: rgba(164,133,58,0.06); }

/* ── Status chip active color ──────────────────────────────────────────────── */
.chip.status-chip.active {
  background: var(--chip-color, var(--ink));
  border-color: var(--chip-color, var(--ink));
  color: white;
}

/* ── Import page ───────────────────────────────────────────────────────────── */
.import-card, .spec-card {
  background: var(--card-front); border: 1px solid var(--rule);
  border-radius: 6px; padding: 28px 32px; margin-bottom: 20px;
}
.import-header {
  display: flex; align-items: flex-start; justify-content: space-between;
  gap: 16px; margin-bottom: 24px; flex-wrap: wrap;
}
.import-title {
  font-family: var(--serif); font-size: 20px; font-weight: 600;
  font-style: italic; color: var(--ink); margin-bottom: 4px;
}
.import-sub {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--ink-mute);
}
.sample-btn {
  font-family: var(--mono); font-size: 11px; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--accent); text-decoration: none;
  border: 1px solid rgba(139,40,24,0.3); border-radius: 4px;
  padding: 7px 14px; white-space: nowrap;
  transition: all 0.15s; background: rgba(139,40,24,0.04);
}
.sample-btn:hover { background: rgba(139,40,24,0.1); border-color: var(--accent); }

/* Upload zone */
.upload-zone {
  border: 2px dashed var(--rule); border-radius: 6px;
  padding: 40px 20px; text-align: center;
  transition: all 0.2s; cursor: pointer; background: var(--bg);
}
.upload-zone.drag-over { border-color: var(--accent); background: rgba(139,40,24,0.04); }
.upload-icon { font-size: 32px; margin-bottom: 10px; }
.upload-text {
  font-family: var(--sans); font-size: 15px; color: var(--ink-soft); margin-bottom: 8px;
}
.upload-browse {
  color: var(--accent); text-decoration: underline; cursor: pointer; font-weight: 500;
}
.upload-hint {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.06em;
  text-transform: uppercase; color: var(--ink-mute);
}
.file-name {
  margin-top: 12px; font-family: var(--mono); font-size: 12px;
  color: var(--green); letter-spacing: 0.04em;
}
.upload-actions { margin-top: 16px; display: flex; justify-content: flex-end; }

/* Result panel */
.result-panel {
  border-radius: 6px; padding: 20px 24px; margin-bottom: 20px;
  border: 1px solid;
}
.result-panel.all-ok   { background: rgba(74,107,58,0.06); border-color: rgba(74,107,58,0.3); }
.result-panel.has-errors { background: rgba(139,40,24,0.04); border-color: rgba(139,40,24,0.25); }
.result-summary { display: flex; gap: 20px; flex-wrap: wrap; margin-bottom: 14px; }
.result-ok   { font-family: var(--sans); font-size: 14px; font-weight: 600; color: var(--green); }
.result-skip { font-family: var(--sans); font-size: 14px; font-weight: 600; color: var(--amber); }
.result-err  { font-family: var(--sans); font-size: 14px; font-weight: 600; color: var(--accent); }

/* Error table */
.error-table {
  width: 100%; border-collapse: collapse;
  font-family: var(--sans); font-size: 13px;
}
.error-table th {
  text-align: left; font-family: var(--mono); font-size: 10px;
  letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-mute);
  border-bottom: 1px solid var(--rule); padding: 6px 8px;
}
.error-table td { padding: 7px 8px; border-bottom: 1px solid var(--rule-soft); color: var(--ink-soft); }
.error-table tr:last-child td { border-bottom: none; }
.error-table .mono { font-family: var(--mono); font-size: 11px; color: var(--accent); }

/* Spec card */
.spec-title {
  font-family: var(--serif); font-size: 18px; font-weight: 600;
  font-style: italic; color: var(--ink); margin-bottom: 16px;
}
.spec-table {
  width: 100%; border-collapse: collapse;
  font-family: var(--sans); font-size: 13px; margin-bottom: 14px;
}
.spec-table th {
  text-align: left; font-family: var(--mono); font-size: 10px;
  letter-spacing: 0.12em; text-transform: uppercase; color: var(--ink-mute);
  border-bottom: 1px solid var(--rule); padding: 6px 10px;
}
.spec-table td { padding: 8px 10px; border-bottom: 1px solid var(--rule-soft); color: var(--ink-soft); }
.spec-table td.mono { font-family: var(--mono); font-size: 11px; color: var(--ink); }
.spec-table tr:last-child td { border-bottom: none; }
.spec-note {
  font-family: var(--mono); font-size: 10px; letter-spacing: 0.06em;
  color: var(--ink-mute); padding-top: 12px; border-top: 1px solid var(--rule-soft);
}

/* ── Workspace + Collapsible Themes Sidebar ────────────────────────────── */
.workspace {
  display: flex;
  gap: 22px;
  align-items: flex-start;
}

.themes-sidebar {
  flex-shrink: 0;
  width: 260px;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background: var(--bg-deep);
  overflow: hidden;
  transition: width 0.2s ease, box-shadow 0.2s;
}

.themes-sidebar.collapsed { width: 42px; }

.sidebar-header {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 9px 14px;
  background: var(--card-front);
  border: none;
  border-bottom: 1px solid var(--rule);
  font-family: var(--mono); font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-mute);
  cursor: pointer;
}
.themes-sidebar.collapsed .sidebar-header { writing-mode: vertical-rl; padding: 12px 6px; border-bottom: none; }

.sidebar-title { font-weight: 500; }
.themes-sidebar.collapsed .sidebar-title { transform: rotate(180deg); }

.chevron { transition: transform 0.2s; }

.sidebar-body {
  max-height: 480px;
  overflow-y: auto;
  padding: 10px;
  display: flex;
  flex-direction: column;
  gap: 5px;
}
.themes-sidebar.collapsed .sidebar-body { display: none; }

.chip.theme-chip,
.chip.all-chip {
  font-size: 12px;
  padding: 6px 13px;
  justify-content: space-between;
}
.chip.theme-chip .theme-name {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 190px;
}

/* Responsive narrowing for smaller desktop */
@media (max-width: 1180px) {
  .themes-sidebar { width: 220px; }
}
@media (max-width: 860px) {
  .workspace { flex-direction: column; }
  .themes-sidebar { width: 100%; }
  .themes-sidebar.collapsed { width: 100%; }
}