/* ── Custom properties ────────────────────────────────── */
:root {
  --c-bg:             #F8FAF3;
  --c-surface:        #FFFFFF;
  --c-primary:        #58CC02;
  --c-primary-hover:  #49AA00;
  --c-primary-3d:     #3a8c00;
  --c-primary-text:   #FFFFFF;
  --c-accent:         #FF9600;
  --c-accent-bg:      #FFF4E0;
  --c-text:           #1c2a14;
  --c-text-muted:     #6b7c60;
  --c-border:         #D9E8C8;
  --c-correct:        #2d8a00;
  --c-correct-bg:     #E7F9D0;
  --c-correct-border: #9FDB6A;
  --c-wrong:          #E53E3E;
  --c-wrong-bg:       #FFF0EE;
  --c-wrong-border:   #FC9A9A;
  --radius-sm: 0.625rem;
  --radius:    0.875rem;
  --radius-lg: 1.25rem;
  --shadow:    0 2px 6px rgba(50,100,0,.08), 0 1px 2px rgba(50,100,0,.04);
  --shadow-md: 0 6px 16px rgba(50,100,0,.10), 0 2px 4px rgba(50,100,0,.04);
  --max-w:     600px;
  --side:      1rem;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --c-bg:             #111111;
    --c-surface:        #1e1e1e;
    --c-primary:        #58CC02;
    --c-primary-hover:  #6be01a;
    --c-primary-3d:     #2b6800;
    --c-accent:         #FF9600;
    --c-accent-bg:      #2a1e00;
    --c-text:           #f0f0f0;
    --c-text-muted:     #888888;
    --c-border:         #2e2e2e;
    --c-correct:        #5fdc1a;
    --c-correct-bg:     #0d2108;
    --c-correct-border: #2d5e14;
    --c-wrong:          #ff6b6b;
    --c-wrong-bg:       #2d0808;
    --c-wrong-border:   #7f1d1d;
  }
}

:root[data-theme="dark"] {
  --c-bg:             #111111;
  --c-surface:        #1e1e1e;
  --c-primary:        #58CC02;
  --c-primary-hover:  #6be01a;
  --c-primary-3d:     #2b6800;
  --c-accent:         #FF9600;
  --c-accent-bg:      #2a1e00;
  --c-text:           #f0f0f0;
  --c-text-muted:     #888888;
  --c-border:         #2e2e2e;
  --c-correct:        #5fdc1a;
  --c-correct-bg:     #0d2108;
  --c-correct-border: #2d5e14;
  --c-wrong:          #ff6b6b;
  --c-wrong-bg:       #2d0808;
  --c-wrong-border:   #7f1d1d;
}

/* ── Reset ────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* ── Base ─────────────────────────────────────────────── */
body {
  background: var(--c-bg);
  color: var(--c-text);
  font-family: 'Nunito', system-ui, -apple-system, 'Segoe UI', sans-serif;
  font-size: 1rem;
  line-height: 1.55;
  min-height: 100dvh;
}

/* ── Header ───────────────────────────────────────────── */
.app-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem var(--side);
  background: color-mix(in srgb, var(--c-surface) 85%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--c-border);
  box-shadow: var(--shadow);
}

.app-logo {
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
  color: var(--c-primary);
}

.header-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  border-radius: 50%;
  border: 1px solid var(--c-border);
  background: var(--c-bg);
  color: var(--c-text-muted);
  cursor: pointer;
  font-size: 1rem;
  line-height: 1;
  transition: background 0.15s, border-color 0.15s, transform 0.2s;
}
.theme-toggle:hover {
  background: var(--c-surface);
  border-color: var(--c-primary);
  transform: rotate(20deg) scale(1.1);
}

.user-chip {
  font-size: 0.82rem;
  background: var(--c-bg);
  border: 1px solid var(--c-border);
  border-radius: 2rem;
  padding: 0.25rem 0.75rem;
  color: var(--c-text-muted);
  cursor: pointer;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}
.user-chip:hover {
  background: var(--c-wrong-bg);
  color: var(--c-wrong);
  border-color: var(--c-wrong-border);
}

/* ── Screens ──────────────────────────────────────────── */
.screen.hidden { display: none; }

@keyframes screenEnter {
  from { opacity: 0; transform: translateY(14px); }
  to   { opacity: 1; transform: translateY(0); }
}
.screen:not(.hidden) {
  animation: screenEnter 0.38s cubic-bezier(0.16, 1, 0.3, 1) both;
}

.screen-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 1.5rem var(--side) 4rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

/* ── Typography ───────────────────────────────────────── */
h1 {
  font-size: clamp(1.4rem, 4vw, 1.875rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

h2 { font-size: 1.1rem; font-weight: 600; }

.lead { color: var(--c-text-muted); font-size: 0.95rem; }

/* ── Form ─────────────────────────────────────────────── */
form { display: flex; flex-direction: column; gap: 0.75rem; }

.field-label {
  display: block;
  font-weight: 600;
  font-size: 0.9rem;
}

.field-input {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1.5px solid var(--c-border);
  border-radius: var(--radius);
  background: var(--c-surface);
  color: var(--c-text);
  font-size: 1rem;
  transition: border-color 0.15s;
  outline: none;
}

.field-input:focus { border-color: var(--c-primary); }

.field-error { color: var(--c-wrong); font-size: 0.85rem; }

/* ── Buttons ──────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 9999px;
  font-size: 1rem;
  font-weight: 800;
  cursor: pointer;
  letter-spacing: 0.01em;
  transition: transform 0.1s, box-shadow 0.1s, background 0.15s;
  min-height: 2.75rem;
  position: relative;
}

.btn:disabled { opacity: 0.4; cursor: not-allowed; }

.btn-primary {
  background: var(--c-primary);
  color: var(--c-primary-text);
  box-shadow: 0 4px 0 var(--c-primary-3d);
}
.btn-primary:not(:disabled):hover {
  background: var(--c-primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 0 var(--c-primary-3d);
}
.btn-primary:not(:disabled):active {
  transform: translateY(3px);
  box-shadow: 0 1px 0 var(--c-primary-3d);
}

.btn-secondary {
  background: var(--c-surface);
  color: var(--c-primary);
  border: 2px solid var(--c-border);
  box-shadow: 0 3px 0 var(--c-border);
}
.btn-secondary:not(:disabled):hover {
  background: var(--c-bg);
  border-color: var(--c-primary);
  box-shadow: 0 3px 0 color-mix(in srgb, var(--c-primary) 40%, transparent);
  transform: translateY(-1px);
}
.btn-secondary:not(:disabled):active {
  transform: translateY(2px);
  box-shadow: 0 1px 0 var(--c-border);
}

.btn-full { width: 100%; }

.btn-back {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  background: none;
  border: none;
  color: var(--c-text-muted);
  font-size: 0.9rem;
  cursor: pointer;
  padding: 0.25rem 0;
  align-self: flex-start;
}
.btn-back:hover { color: var(--c-primary); }

/* ── Mode grid ────────────────────────────────────────── */
.mode-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

.mode-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.3rem;
  padding: 1rem;
  background: var(--c-surface);
  border: 1.5px solid var(--c-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  cursor: pointer;
  text-align: left;
  transition: border-color 0.2s, box-shadow 0.2s, transform 0.2s;
  min-height: 7rem;
  color: var(--c-text);
}

.mode-card:not(:disabled):hover {
  border-color: var(--c-primary);
  box-shadow: 0 8px 24px rgba(50,100,0,.12);
  transform: translateY(-4px);
}

.mode-card:not(:disabled):active { transform: translateY(-1px) scale(0.99); }

.mode-card--soon { opacity: 0.45; cursor: not-allowed; }

/* colored top-border accent per card */
.mode-card:nth-child(1) { border-top: 3px solid #58CC02; }
.mode-card:nth-child(2) { border-top: 3px solid #FF9600; }
.mode-card:nth-child(3) { border-top: 3px solid #CE82FF; }
.mode-card:nth-child(4) { border-top: 3px solid #FF4B4B; }

.mode-icon { font-size: 1.75rem; line-height: 1; }
.mode-name { font-weight: 800; font-size: 0.95rem; }
.mode-desc { color: var(--c-text-muted); font-size: 0.8rem; }

/* ── Overall progress card ────────────────────────────── */
.overall-progress-card {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  padding: 1rem 1.25rem;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.overall-progress-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.overall-progress-title {
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--c-text);
}

.overall-progress-label {
  font-size: 0.8rem;
  color: var(--c-text-muted);
  font-weight: 500;
}

.overall-progress-track {
  height: 10px;
  background: var(--c-border);
  border-radius: 5px;
  overflow: hidden;
}

.overall-progress-fill {
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--c-primary), var(--c-accent));
  border-radius: 5px;
  transition: width 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

/* ── Topic list ───────────────────────────────────────── */
.topic-list { display: flex; flex-direction: column; gap: 0.6rem; }

.topic-btn {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 0.85rem 1.1rem;
  background: var(--c-surface);
  border: 1.5px solid var(--c-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  cursor: pointer;
  font-size: 0.95rem;
  font-weight: 600;
  text-align: left;
  color: var(--c-text);
  transition: border-color 0.15s, transform 0.15s, box-shadow 0.15s;
  gap: 0.75rem;
}

.topic-btn:not(:disabled):hover {
  border-color: var(--c-primary);
  transform: translateX(3px);
  box-shadow: var(--shadow-md);
}
.topic-btn:disabled { opacity: 0.4; cursor: not-allowed; }

.topic-btn-left {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  flex: 1;
  min-width: 0;
}

.topic-day-badge {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--c-primary);
}

.topic-name {
  font-size: 0.92rem;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.topic-mini-bar {
  height: 4px;
  background: var(--c-border);
  border-radius: 2px;
  overflow: hidden;
  margin-top: 0.15rem;
}

.topic-mini-fill {
  height: 100%;
  background: var(--c-correct);
  border-radius: 2px;
  transition: width 0.3s ease;
}

.topic-btn-meta {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.1rem;
  flex-shrink: 0;
}

.topic-count  { font-size: 0.8rem; color: var(--c-text-muted); font-weight: 400; }
.topic-weight { font-size: 0.75rem; color: var(--c-text-muted); font-weight: 400; }
.status-good  { color: var(--c-correct) !important; font-weight: 600 !important; }
.status-warn  { color: #d97706; font-weight: 600 !important; }

/* ── Question screen ──────────────────────────────────── */
.question-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.question-counter {
  font-size: 0.85rem;
  color: var(--c-text-muted);
  font-weight: 600;
}

.progress-track {
  height: 6px;
  background: var(--c-border);
  border-radius: 3px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--c-primary), var(--c-accent));
  border-radius: 3px;
  transition: width 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}

.question-card {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.type-hint {
  font-size: 0.78rem;
  color: var(--c-text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.question-text {
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.6;
}

/* ── Options ──────────────────────────────────────────── */
.options-list { display: flex; flex-direction: column; gap: 0.5rem; }

.option-btn {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  width: 100%;
  padding: 0.8rem 1rem;
  background: var(--c-bg);
  border: 1.5px solid var(--c-border);
  border-radius: var(--radius);
  cursor: pointer;
  text-align: left;
  color: var(--c-text);
  font-size: 0.95rem;
  line-height: 1.45;
  transition: border-color 0.12s, background 0.12s, transform 0.1s;
}

.option-btn:hover:not(:disabled):not([aria-pressed="true"]) {
  border-color: var(--c-primary);
  background: var(--c-surface);
}

.option-btn[aria-pressed="true"] {
  border-color: var(--c-primary);
  background: var(--c-surface);
  transform: scale(1.01);
}

.option-btn.correct {
  border-color: var(--c-correct-border);
  background: var(--c-correct-bg);
  color: var(--c-correct);
}

.option-btn.wrong {
  border-color: var(--c-wrong-border);
  background: var(--c-wrong-bg);
  color: var(--c-wrong);
}

.option-btn:disabled { cursor: default; }

.option-key {
  flex-shrink: 0;
  width: 1.5rem;
  height: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--c-border);
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--c-text-muted);
  transition: background 0.12s, color 0.12s;
}

.option-btn[aria-pressed="true"] .option-key {
  background: var(--c-primary);
  color: #fff;
}

.option-btn.correct .option-key { background: var(--c-correct); color: #fff; }
.option-btn.wrong   .option-key { background: var(--c-wrong);   color: #fff; }

/* ── Result banner ────────────────────────────────────── */
@keyframes bannerPop {
  from { transform: scale(0.88) translateY(-6px); opacity: 0; }
  to   { transform: scale(1)    translateY(0);    opacity: 1; }
}

.result-banner {
  border-radius: var(--radius-lg);
  padding: 1rem 1.25rem;
  font-size: 1.1rem;
  font-weight: 700;
  text-align: center;
  animation: bannerPop 0.3s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

.result-banner.correct {
  background: var(--c-correct-bg);
  color: var(--c-correct);
  border: 1.5px solid var(--c-correct-border);
}

.result-banner.wrong {
  background: var(--c-wrong-bg);
  color: var(--c-wrong);
  border: 1.5px solid var(--c-wrong-border);
}

/* ── Card / Explanation ───────────────────────────────── */
.card {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  box-shadow: var(--shadow);
}

.explanation-card { display: flex; flex-direction: column; gap: 0.6rem; }

.explanation-text {
  color: var(--c-text-muted);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* ── Summary ──────────────────────────────────────────── */
.summary-score-wrap { text-align: center; padding: 0.5rem 0; }

.summary-score {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 0.35rem;
}

.score-correct {
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--c-primary);
  line-height: 1;
}

.score-divider { font-size: 2rem; color: var(--c-text-muted); }
.score-total   { font-size: 2rem; font-weight: 700; color: var(--c-text-muted); }

.summary-percent {
  margin-top: 0.4rem;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--c-text-muted);
}

.summary-message { text-align: center; color: var(--c-text-muted); }

.summary-wrong-wrap { display: flex; flex-direction: column; gap: 0.6rem; }

.summary-wrong-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.summary-wrong-item {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  padding: 0.7rem 1rem;
  font-size: 0.9rem;
  color: var(--c-text-muted);
}

.summary-actions { display: flex; gap: 0.75rem; }
.summary-actions .btn { flex: 1; }

/* ── Question nav right ───────────────────────────────── */
.question-nav-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* ── Exam timer & badge ───────────────────────────────── */
.exam-timer {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--c-text);
  background: var(--c-bg);
  border: 1.5px solid var(--c-border);
  border-radius: 2rem;
  padding: 0.2rem 0.65rem;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.03em;
  transition: color 0.2s, background 0.2s, border-color 0.2s;
}

.exam-timer--warn {
  color: var(--c-wrong);
  background: var(--c-wrong-bg);
  border-color: var(--c-wrong-border);
}

.exam-mode-badge {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--c-primary);
  border: 1px solid var(--c-primary);
  border-radius: 2rem;
  padding: 0.15rem 0.5rem;
}

/* ── Exam summary ─────────────────────────────────────── */
.exam-verdict {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
  font-size: 1.4rem;
  font-weight: 800;
  text-align: center;
}

.exam-verdict--pass {
  background: var(--c-correct-bg);
  color: var(--c-correct);
  border: 2px solid var(--c-correct-border);
}

.exam-verdict--fail {
  background: var(--c-wrong-bg);
  color: var(--c-wrong);
  border: 2px solid var(--c-wrong-border);
}

.exam-verdict-icon { font-size: 1.8rem; }

.exam-topic-results {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-top: 0.75rem;
}

.exam-topic-row {
  display: grid;
  grid-template-columns: 1fr auto auto;
  align-items: center;
  gap: 0.6rem;
}

.exam-topic-label {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--c-text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.exam-topic-bar {
  width: 80px;
  height: 8px;
  background: var(--c-border);
  border-radius: 4px;
  overflow: hidden;
  flex-shrink: 0;
}

.exam-topic-fill {
  height: 100%;
  border-radius: 4px;
  transition: width 0.5s ease;
}

.exam-topic-fill--pass { background: var(--c-correct); }
.exam-topic-fill--fail { background: #f59e0b; }

.exam-topic-pct {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--c-text-muted);
  width: 3.5rem;
  text-align: right;
  flex-shrink: 0;
}

.exam-save-status {
  font-size: 0.82rem;
  text-align: center;
  min-height: 1.4em;
  margin: 0.25rem 0 0.5rem;
}
.exam-save-status--pending { color: var(--c-text-muted); }
.exam-save-status--ok      { color: var(--c-correct); }
.exam-save-status--err     { color: var(--c-wrong); }

/* ── Flashcard ────────────────────────────────────────── */
.fc-known-badge {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--c-correct);
  background: var(--c-correct-bg);
  border: 1px solid var(--c-correct-border);
  border-radius: 2rem;
  padding: 0.15rem 0.55rem;
}

.flashcard-scene {
  perspective: 900px;
  cursor: pointer;
  outline: none;
  border-radius: var(--radius-lg);
}

.flashcard-scene:focus-visible {
  box-shadow: 0 0 0 3px var(--c-primary);
}

.flashcard {
  display: grid;
  transform-style: preserve-3d;
  transition: transform 0.5s cubic-bezier(0.16, 1, 0.3, 1);
  user-select: none;
}

.flashcard.flipped {
  transform: rotateY(180deg);
}

.flashcard-face {
  grid-row: 1;
  grid-column: 1;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  background: var(--c-surface);
  border: 1.5px solid var(--c-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-md);
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  min-height: 200px;
}

.flashcard-back {
  transform: rotateY(180deg);
  background: var(--c-bg);
  border-color: var(--c-primary);
}

.fc-face-label {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--c-primary);
}

.fc-question-text {
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.6;
  flex: 1;
}

.fc-tap-hint {
  font-size: 0.78rem;
  color: var(--c-text-muted);
  text-align: center;
  margin-top: auto;
}

.fc-answer {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.fc-answer-item {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--c-text);
}

.fc-answer-key {
  flex-shrink: 0;
  width: 1.5rem;
  height: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--c-correct);
  color: #fff;
  font-size: 0.78rem;
  font-weight: 700;
}

.fc-divider {
  height: 1px;
  background: var(--c-border);
  margin: 0.25rem 0;
}

.fc-explanation-text {
  font-size: 0.88rem;
  color: var(--c-text-muted);
  line-height: 1.6;
}

.fc-actions {
  display: flex;
  gap: 0.75rem;
}

.fc-actions .btn { flex: 1; }

.fc-flip-hint {
  text-align: center;
  font-size: 0.82rem;
  color: var(--c-text-muted);
  padding: 0.25rem 0;
}

/* ── Flashcard summary ────────────────────────────────── */
.fc-summary-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

.fc-summary-stat {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.3rem;
  box-shadow: var(--shadow);
}

.fc-sum-num {
  font-size: 2.5rem;
  font-weight: 800;
  line-height: 1;
}

.fc-sum-num--known  { color: var(--c-correct); }
.fc-sum-num--review { color: #d97706; }

.fc-sum-label {
  font-size: 0.82rem;
  color: var(--c-text-muted);
  font-weight: 500;
}

/* ── Leaderboard ──────────────────────────────────────── */
.lb-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.25rem;
}

.btn-sm {
  font-size: 0.78rem;
  padding: 0.3rem 0.7rem;
}

.lb-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.lb-tab {
  padding: 0.35rem 0.85rem;
  font-size: 0.82rem;
  font-weight: 600;
  border: 1.5px solid var(--c-border);
  border-radius: 2rem;
  background: var(--c-surface);
  color: var(--c-text-muted);
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s, background 0.15s;
}

.lb-tab:hover { border-color: var(--c-primary); color: var(--c-primary); }

.lb-tab--active {
  border-color: var(--c-primary);
  background: var(--c-primary);
  color: var(--c-primary-text);
}

.lb-content { margin-top: 0.25rem; }

.lb-loading, .lb-error, .lb-empty {
  text-align: center;
  color: var(--c-text-muted);
  font-size: 0.95rem;
  padding: 2rem 0;
}

.lb-error { color: var(--c-wrong); }

.lb-table {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.lb-row {
  display: grid;
  grid-template-columns: 2.5rem 1fr auto;
  align-items: center;
  padding: 0.85rem 1.1rem;
  gap: 0.75rem;
  border-bottom: 1px solid var(--c-border);
  transition: background 0.12s;
}

.lb-row:last-child { border-bottom: none; }

.lb-row:hover { background: var(--c-bg); }

.lb-row--me {
  background: color-mix(in srgb, var(--c-primary) 8%, var(--c-surface));
  font-weight: 600;
}

.lb-rank {
  font-size: 1rem;
  text-align: center;
  font-weight: 700;
  color: var(--c-text-muted);
}

.lb-name {
  font-size: 0.95rem;
  color: var(--c-text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.lb-score {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--c-text-muted);
}

.lb-score--pass { color: var(--c-correct); }

/* ── Mascot ───────────────────────────────────────────── */
@keyframes mascotJump {
  0%   { transform: translateY(0)    scale(1)    rotate(0deg); }
  18%  { transform: translateY(-22px) scale(1.06) rotate(-6deg); }
  42%  { transform: translateY(-48px) scale(1.13) rotate(5deg); }
  62%  { transform: translateY(-26px) scale(1.04) rotate(-3deg); }
  80%  { transform: translateY(-8px)  scale(1.01) rotate(2deg); }
  100% { transform: translateY(0)    scale(1)    rotate(0deg); }
}

@keyframes mascotShake {
  0%, 100% { transform: translateX(0)   rotate(0deg); }
  14%       { transform: translateX(-7px) rotate(-9deg); }
  32%       { transform: translateX(7px)  rotate(9deg); }
  50%       { transform: translateX(-5px) rotate(-6deg); }
  70%       { transform: translateX(5px)  rotate(6deg); }
  88%       { transform: translateX(-2px) rotate(-2deg); }
}

@keyframes bubblePop {
  from { transform: scale(0.55) translateY(8px); opacity: 0; }
  to   { transform: scale(1)    translateY(0);   opacity: 1; }
}

.mascot {
  position: fixed;
  bottom: -180px;
  left: 50%;
  translate: -50% 0;
  z-index: 200;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.55rem;
  transition: bottom 0.48s cubic-bezier(0.34, 1.56, 0.64, 1);
  pointer-events: none;
  user-select: none;
}

.mascot--show { bottom: 1.5rem; }

.mascot-bubble {
  order: -1;
  border-radius: 1.5rem;
  padding: 0.45rem 1.1rem;
  font-size: 0.92rem;
  font-weight: 700;
  box-shadow: 0 4px 20px rgba(0,0,0,.13);
  white-space: nowrap;
  border: 2px solid var(--c-border);
  background: var(--c-surface);
  color: var(--c-text);
}

.mascot--show    .mascot-bubble { animation: bubblePop 0.32s cubic-bezier(0.34, 1.56, 0.64, 1) both; }
.mascot--correct .mascot-bubble { background: var(--c-correct-bg);  border-color: var(--c-correct-border); color: var(--c-correct); }
.mascot--wrong   .mascot-bubble { background: var(--c-wrong-bg);    border-color: var(--c-wrong-border);   color: var(--c-wrong); }

.mascot-face {
  font-size: 3rem;
  line-height: 1;
  filter: drop-shadow(0 2px 8px rgba(0,0,0,.18));
}

.mascot--correct .mascot-face { animation: mascotJump  0.8s cubic-bezier(0.34, 1.56, 0.64, 1) both; }
.mascot--wrong   .mascot-face { animation: mascotShake 0.55s ease both; }

/* ── Utility ──────────────────────────────────────────── */
.hidden { display: none !important; }