.fc-progress-pill{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-pill);padding:10px 18px;font-size:.9rem}.fc-stage{flex-direction:column;gap:20px;display:flex}.fc-card-scene{perspective:1200px;height:390px}.fc-card-3d{width:100%;height:100%;transform-style:preserve-3d;transition:transform .55s var(--ease-expo);cursor:pointer;position:relative}.fc-card-3d.is-flipped{transform:rotateY(180deg)}.fc-face{backface-visibility:hidden;flex-direction:column;justify-content:space-between;padding:28px;display:flex;position:absolute;inset:0}.fc-back{transform:rotateY(180deg)}.fc-card-top,.fc-card-foot{color:var(--text-muted);justify-content:space-between;align-items:center;font-size:.82rem;display:flex}.fc-center-content{text-align:center;margin:auto 0}.fc-katex-display{color:var(--primary);margin-bottom:16px;font-size:1.5rem}.fc-explanation{color:var(--text-primary);margin-bottom:10px;font-size:.95rem}.fc-example-box{color:var(--text-secondary);background:var(--bg);border-radius:var(--radius-sm);padding:10px 14px;font-size:.85rem;display:inline-block}.fc-controls-bar{flex-wrap:wrap;justify-content:center;gap:12px;display:flex}