.practice-navigator{display:flex;align-items:center;justify-content:center;gap:16px;margin-bottom:14px}
.question-image{margin:12px 0;padding:10px;border:1px solid var(--line);border-radius:10px;background:#fbfdff}
.question-image img{display:block;width:100%;max-height:430px;object-fit:contain;border-radius:7px;background:#fff}
.review-card .question-image{max-width:640px}
.review-card .question-image img{max-height:260px}
.learn-item{display:flex;justify-content:space-between;align-items:center;gap:16px;padding:13px 0;border-bottom:1px solid var(--line)}
.learn-item:last-child{border-bottom:0}
.learn-item b{display:block;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;max-width:72vw}
.learn-item span{display:block;margin-top:4px;font-size:12px;color:var(--muted)}
.stat-button{text-align:left;border:0;cursor:pointer}
.smart-import-panel{margin-top:18px}
.smart-import-panel .section-note{margin:3px 0 0;color:var(--muted);font-size:12px}
.mindmap-universe{position:relative;min-height:min(72vh,680px);display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:34px 26px;align-items:center;padding:46px 36px;border-radius:22px;overflow:clip;background:radial-gradient(circle at 12% 18%,#dff4ff,transparent 27%),radial-gradient(circle at 83% 72%,#e6fffb,transparent 30%),linear-gradient(140deg,#f4f8ff,#effdfa);border:1px solid #dcecf8}
.map-sphere{position:relative;width:min(215px,74vw);aspect-ratio:1;margin:auto;border:0;border-radius:50%;padding:18px;display:grid;align-content:center;justify-items:center;gap:6px;color:#fff;background:radial-gradient(circle at 32% 25%,rgba(255,255,255,.42),transparent 23%),linear-gradient(145deg,var(--sphere),#10294d);box-shadow:0 22px 48px rgba(25,62,108,.28),inset -18px -24px 48px rgba(0,0,0,.24);transform:translate3d(calc(var(--dx,0px)*var(--scatter,1)),calc(var(--dy,0px)*var(--scatter,1)),0) scale(var(--scale,1)) rotate(var(--tilt,0deg));animation:sphereFloat var(--duration,4.5s) ease-in-out infinite;animation-delay:var(--delay);will-change:transform}
.map-sphere:hover{transform:translate3d(calc(var(--dx,0px)*var(--scatter,1)),calc((var(--dy,0px) - 6px)*var(--scatter,1)),0) scale(calc(var(--scale,1)*1.02)) rotate(var(--tilt,0deg));z-index:2}
.map-sphere .sphere-orbit{position:absolute;inset:-8%;border:1px solid rgba(65,125,190,.28);border-radius:50%}
.map-sphere .sphere-title{font-size:24px;font-weight:800;text-shadow:0 3px 10px rgba(0,0,0,.22)}
.map-sphere small{background:rgba(255,255,255,.16);padding:5px 10px;border-radius:999px;font-size:12px}
.chapter-section-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:16px}
.section-card{cursor:pointer;padding:22px;border:1px solid var(--line);border-radius:11px;background:#fff;box-shadow:var(--shadow);display:grid;gap:10px}
.section-card:hover{border-color:#a5c8f4;transform:translateY(-2px)}
.section-card b{font-size:18px;line-height:1.4}
.section-card span{color:var(--muted);font-size:12px}
.section-badge{width:fit-content;padding:4px 9px;border-radius:6px;background:#e8f2ff;color:#2c6ecb;font-weight:800;font-size:13px}
@keyframes sphereFloat{
  0%,100%{transform:translate3d(calc(var(--dx,0px)*var(--scatter,1)),calc(var(--dy,0px)*var(--scatter,1)),0) scale(var(--scale,1)) rotate(var(--tilt,0deg))}
  50%{transform:translate3d(calc((var(--dx,0px) + 4px)*var(--scatter,1)),calc((var(--dy,0px) - 10px)*var(--scatter,1)),0) scale(var(--scale,1)) rotate(calc(var(--tilt,0deg) + .6deg))}
}
@media(max-width:900px){.mindmap-universe{--scatter:.72;padding:26px 20px}}
@media(max-width:640px){.mindmap-universe{--scatter:.48;padding:28px 18px;gap:20px}.map-sphere{width:min(155px,66vw)}.sphere-title{font-size:20px}.learn-item b{white-space:normal;max-width:none}}