/* Keep these rules scoped: lesson-player navigation retains its own layout. */
#library-parts.study-part-nav.part-scroller,.exam-library-parts.part-scroller{display:block;box-sizing:border-box;min-width:0;width:100%;max-width:100%;margin:24px 0;padding:0;border:0;border-radius:0;background:transparent;overflow:visible;box-shadow:none}
#library-parts.study-part-nav.part-scroller[hidden],.part-scroller [hidden]{display:none!important}
.part-scroller .part-scroller-row{display:flex;align-items:center;justify-content:center;gap:10px;padding:10px;border:1px solid #e3e7e2;border-radius:24px;background:#fff;direction:ltr;min-width:0}
.part-scroller .part-scroller-track{display:flex;flex:1;min-width:0;max-width:calc(var(--part-set-width)*2 - var(--part-item-width) - 10px);gap:10px;overflow-x:auto;overflow-y:hidden;scroll-snap-type:x mandatory;scrollbar-width:none;overscroll-behavior-x:contain;mask-image:linear-gradient(90deg,transparent,#000 6%,#000 94%,transparent);-webkit-mask-image:linear-gradient(90deg,transparent,#000 6%,#000 94%,transparent);touch-action:pan-x pan-y;cursor:grab}
.part-scroller .part-scroller-track::-webkit-scrollbar{display:none}
.part-scroller .part-scroller-track:active{cursor:grabbing}
#library-parts.study-part-nav.part-scroller .part-scroller-item,.part-scroller.exam-library-parts .part-scroller-item{box-sizing:border-box;flex:0 0 var(--part-item-width);width:var(--part-item-width);min-width:var(--part-item-width);max-width:var(--part-item-width);height:56px;min-height:56px;padding:0 10px;border:1px solid #e3e7e2;border-radius:14px;background:#f7f9f6;color:#55625a;font-size:20px;font-weight:700;line-height:1.2;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;scroll-snap-align:start;user-select:none;box-shadow:none}
#library-parts.study-part-nav.part-scroller .part-scroller-item[aria-pressed=true],.part-scroller.exam-library-parts .part-scroller-item[aria-pressed=true]{background:#10231a;color:#fff;box-shadow:0 2px 8px #10231a2e}
.part-scroller .part-scroller-item:disabled{opacity:.55}
#library-parts.study-part-nav.part-scroller .part-scroller-arrow,.part-scroller.exam-library-parts .part-scroller-arrow{box-sizing:border-box;flex:0 0 48px;width:48px;min-width:48px;height:48px;min-height:48px;padding:0;border-radius:14px;background:#f7f9f6;border:1px solid #e3e7e2;color:#10231a;font-size:26px;line-height:1}
.part-scroller button:focus-visible{outline:3px solid #00a67d;outline-offset:-4px}
.part-scroller .part-scroller-controls{display:flex;align-items:center;justify-content:flex-end;gap:8px;flex-wrap:wrap;margin-top:8px}
.part-scroller .part-scroller-hint{padding:8px 14px;border-radius:999px;background:#10231a;color:white;font-size:15px;font-weight:600;line-height:1.4;text-align:center}
#library-parts.study-part-nav.part-scroller .part-scroller-sound,.part-scroller.exam-library-parts .part-scroller-sound{flex:0 0 auto;min-width:0;min-height:36px;padding:5px 12px;font-size:13px;font-weight:600;border:1px solid #e3e7e2;border-radius:999px;background:#f7f9f6;color:#55625a;white-space:nowrap}
@media(max-width:480px){.part-scroller .part-scroller-row{gap:6px;padding:8px}.part-scroller .part-scroller-hint{font-size:13px}}

/* Static computer tabs: one copy, full labels, no automatic movement or sound. */
.part-scroller-static .part-scroller-track{max-width:none;flex-wrap:wrap;overflow:visible;scroll-snap-type:none;mask-image:none;-webkit-mask-image:none;cursor:default;gap:8px;touch-action:auto}
#library-parts.study-part-nav.part-scroller-static .part-scroller-item,.part-scroller.exam-library-parts.part-scroller-static .part-scroller-item{flex:1 0 auto;width:auto;min-width:110px;max-width:none;height:auto;min-height:48px;padding:12px 16px;font-size:16px;overflow:visible;text-overflow:clip;white-space:nowrap;scroll-snap-align:none}