.exercise-card { max-width: 700px; margin: 30px auto; }
    .exercise-header-stats {
      font-size: 14px; color: var(--text-secondary);
      margin-bottom: 20px; padding-bottom: 14px;
      border-bottom: 1px solid var(--border);
    }
    .exercise-question { margin: 20px 0; font-size: 16px; }
    .exercise-question strong { color: var(--primary); }
    .exercise-options { margin: 20px 0; padding-left: 0; list-style: none; }
    .exercise-options li { margin-bottom: 10px; }
    .exercise-options label {
      display: flex; align-items: center; gap: 10px; cursor: pointer;
      padding: 12px 16px; border-radius: var(--radius-md);
      border: 1px solid var(--border);
      transition: all var(--transition);
    }
    .exercise-options label:hover { background: var(--bg); border-color: var(--border-hover); }
    .exercise-buttons { display: flex; gap: 12px; margin-top: 20px; }
    .exercise-feedback {
      margin-top: 16px; padding: 14px 18px;
      background: var(--bg); border-radius: var(--radius-md);
      font-size: 14px; line-height: 1.6;
    }
    .correct-feedback { color: var(--color-success); }
    .wrong-feedback { color: var(--color-error); }
    @media (max-width: 768px) {
      .exercise-buttons { flex-direction: column; }
      .exercise-buttons button { width: 100%; }
    }
    [data-theme="dark"] .exercise-options label {
        background: var(--surface);
      }
.exercise-data-panel { display: none; margin-bottom: 20px; padding: 16px; background: var(--bg); border-radius: var(--radius-md); border: 1px solid var(--border); }
.exercise-data-heading { display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; }
#exercise-heatmap .exercise-data-heading { margin-bottom: 8px; }
.exercise-data-title { font-weight: 600; font-size: 15px; }
#streak-badge { font-size: 13px; color: var(--primary); }
.exercise-data-caption { font-size: 11px; color: var(--text-muted); }
#stats-trend-chart { display: flex; align-items: flex-end; gap: 0; height: 72px; margin-bottom: 8px; }
#stats-trend-labels { display: flex; gap: 0; font-size: 10px; color: var(--text-muted); }
.exercise-save-status { margin-top: 10px; color: var(--text-muted); }
.exercise-save-status.success { color: var(--color-success); }
.exercise-save-status.error { color: var(--color-error); }
.exercise-filters { margin-bottom: 20px; }
.exercise-filter-row { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.exercise-filter-row:first-child { margin-bottom: 10px; }
.exercise-filter-label { font-size: 12px; font-weight: 600; color: var(--text-muted); text-transform: uppercase; letter-spacing: .5px; }
.exercise-pill-group { display: flex; gap: 4px; }