.mc-course-player__sidebar{min-width:0}.mc-course-player__topics{scrollbar-width:thin;scrollbar-color:#cbd5e1 transparent}.mc-course-player__topic{position:relative}.mc-course-player__topic h3{position:relative;padding-left:38px!important;cursor:pointer;user-select:none;-webkit-tap-highlight-color:transparent}.mc-course-player__topic h3:before{content:"";position:absolute;left:17px;top:50%;width:0;height:0;border-top:5px solid transparent;border-bottom:5px solid transparent;border-left:6px solid #7b8794;transform:translateY(-50%);transition:transform .18s ease,border-left-color .18s ease}.mc-course-player__topic.is-open h3:before{transform:translateY(-50%) rotate(90deg);border-left-color:#1769e0}.mc-course-player__topic h3:hover{background:#f3f7fb}.mc-course-player__topic.is-open h3{color:#123b63;background:#f6f9fc}.mc-course-player__topic:not(.is-open) .mc-course-player__lessons{display:none}.mc-course-player__topic .mc-course-player__lessons{animation:mcOutlineOpen .16s ease-out}@keyframes mcOutlineOpen{from{opacity:.45;transform:translateY(-3px)}to{opacity:1;transform:translateY(0)}}
/* Chapter completion cue: no extra markup or business logic required. */
.mc-course-player__topic.is-open h3{box-shadow:inset 3px 0 0 #1769e0}.mc-course-player__topic h3:after{content:"";position:absolute;right:14px;top:50%;width:5px;height:5px;border-radius:50%;background:#d7dee7;transform:translateY(-50%)}.mc-course-player__topic.is-open h3:after{background:#8bb8ed}.mc-course-player__topic:has(.mc-course-player__item.is-complete) h3:after{background:#48b889}.mc-course-player__topic:has(.mc-course-player__item.is-active) h3:after{width:7px;height:7px;background:#ff9418;box-shadow:0 0 0 3px rgba(255,148,24,.12)}
@media(min-width:901px){.mc-course-player__sidebar{position:sticky;top:18px;align-self:start;max-height:calc(100vh - 36px);display:flex;flex-direction:column;overflow:hidden}.mc-course-player__sidebar-head{flex:0 0 auto}.mc-course-player__topics{min-height:0;overflow-y:auto;overscroll-behavior:contain;padding-right:3px}.mc-course-player__topics::-webkit-scrollbar{width:7px}.mc-course-player__topics::-webkit-scrollbar-track{background:transparent}.mc-course-player__topics::-webkit-scrollbar-thumb{background:#d5dde6;border-radius:999px}.mc-course-player__topics::-webkit-scrollbar-thumb:hover{background:#b9c5d2}.mc-course-player__topic h3{min-height:44px;box-sizing:border-box;display:flex;align-items:center}.mc-course-player__lessons{padding:6px 9px 8px}.mc-course-player__item{min-height:40px;margin:2px 0;padding:9px 10px}.mc-course-player__item.is-active{font-weight:700;box-shadow:inset 3px 0 0 #ff9418}.mc-course-player__item.is-active>span:nth-child(2){letter-spacing:.005em}.mc-course-player__item.is-complete .mc-course-player__check{font-weight:800}}
@media(max-width:900px){.mc-course-player__topics{max-height:none;overflow:visible}}
@media(max-width:600px){.mc-course-player__topic h3{padding-left:38px!important}.mc-course-player__topic h3:before{left:15px}.mc-course-player__topic.is-open h3{background:#f7fafc}.mc-course-player__lessons{padding:5px 7px 7px}.mc-course-player__item{min-height:42px;padding:9px 8px}}
@media(prefers-reduced-motion:reduce){.mc-course-player__topic h3:before,.mc-course-player__topic .mc-course-player__lessons{transition:none;animation:none}}