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.cave-hit-title{color:var(--accent)}.cave-hit-excerpt{color:var(--ink-500);margin-top:2px;font-size:14.5px;line-height:1.6;display:block}.cave-hit mark{background:var(--accent-soft);color:var(--ink-900)}.cave-grid{grid-template-columns:1fr;gap:0;display:grid}@media (width>=640px){.cave-grid{grid-template-columns:repeat(2,1fr)}}@media (width>=1000px){.cave-grid{grid-template-columns:repeat(3,1fr)}}.cave-card{border:1px solid var(--line);flex-direction:column;gap:12px;margin:0 -1px -1px 0;padding:22px;transition:background .14s;display:flex;position:relative}.cave-card[hidden]{display:none}.cave-card:hover{background:var(--paper-alt)}.cave-card:hover .cave-card-title{color:var(--accent)}.cave-card-top{justify-content:space-between;align-items:center;gap:10px;display:flex}.cave-card-title{letter-spacing:-.02em;color:var(--ink-900);margin:0;font-size:19px;font-weight:620;line-height:1.32;transition:color .14s}.cave-card-title a{z-index:1;text-decoration:none;position:relative}.cave-card-title a:hover{text-underline-offset:3px;text-decoration:underline}.cave-card-sub{color:var(--ink-500);flex:1;margin:0;font-size:14.5px;line-height:1.6}.cave-card-foot{border-top:1px solid var(--line);font-family:var(--font-mono);color:var(--ink-400);letter-spacing:.04em;align-items:center;gap:8px;padding-top:12px;font-size:11px;text-decoration:none;display:flex}.cave-card-foot:after{content:"";position:absolute;inset:0}.cave-card-bar{background:var(--ink-150);flex:1;height:2px;overflow:hidden}.cave-card-bar span{background:var(--accent);width:0;height:100%;display:block}.cave-tag{border:1px solid var(--line-strong);font-family:var(--font-mono);letter-spacing:.06em;text-transform:uppercase;color:var(--ink-500);white-space:nowrap;padding:2px 8px;font-size:10.5px}.cave-empty{text-align:center;color:var(--ink-400);border-bottom:1px solid var(--line);grid-column:1/-1;padding:64px 24px;font-size:15px}.cave-sitelinks{font-family:var(--font-mono);letter-spacing:.04em;color:var(--ink-400);flex-wrap:wrap;gap:4px 16px;font-size:11px;display:flex}.cave-rail-title a,.cave-sitelinks a{text-decoration:none}.cave-rail-title a:hover,.cave-sitelinks a:hover{color:var(--accent)}.cave-home>.cave-sitelinks{border-top:1px solid var(--line);margin-top:72px;padding-top:18px}.cave-page{max-width:var(--prose)}.cave-course{border-top:1px solid var(--line);margin:44px 0 0;padding:0;list-style:none}.cave-course a{border-bottom:1px solid var(--line);align-items:baseline;gap:16px;padding:20px 0;text-decoration:none;display:flex}.cave-course-title{letter-spacing:-.02em;color:var(--ink-900);transition:color var(--duration-quick) var(--ease-smooth-out);font-size:19px;font-weight:620;line-height:1.35;display:block}.cave-course a:hover .cave-course-title{color:var(--accent)}.cave-course-lede{color:var(--ink-500);margin-top:6px;font-size:15.5px;line-height:1.6;display:block}.cave-course .mono-label{margin-top:10px;display:block}.cave-course-done{color:var(--ok);display:none}.cave-course .is-done .cave-course-done{display:inline}@media (width<=900px){body{font-size:16.5px}.cave-railbtn{display:flex}.cave-rail{width:min(84vw, var(--rail));transition:transform .22s;transform:translate(-100%)}.cave-rail.is-open{transform:none;box-shadow:0 0 40px #0000002e}.cave-scrim.is-open{display:block}.cave-main{margin-left:0;padding:68px 20px 96px}.cave-term{grid-template-columns:1fr;gap:4px}}@media print{.cave-rail,.cave-railbtn,.cave-pager,.cave-done,.cave-scrim{display:none!important}.cave-main{margin-left:0}}::view-transition-old(root){animation:cave-page-out var(--duration-quick) var(--ease-smooth-out) both}::view-transition-new(root){animation:cave-page-in var(--duration-fast) var(--ease-smooth-out) both}@keyframes cave-page-out{to{opacity:0;filter:blur(var(--blur-small))}}@keyframes cave-page-in{0%{opacity:0;transform:translateY(var(--page-slide-distance));filter:blur(var(--blur-medium))}}.cave-rail{view-transition-name:cave-rail}.cave-eyebrow,.cave-h1,.cave-lede,.cave-meta{animation:cave-rise var(--duration-very-slow) var(--ease-smooth-out) both}.cave-h1{animation-delay:var(--duration-stagger)}.cave-lede{animation-delay:calc(var(--duration-stagger) * 2)}.cave-meta{animation-delay:calc(var(--duration-stagger) * 3)}@keyframes cave-rise{0%{opacity:0;transform:translateY(var(--distance-medium));filter:blur(var(--blur-medium))}}.cave-note>.mono-label{align-items:center;gap:6px;display:flex}.cave-note>.mono-label svg{flex-shrink:0}.cave-opt{transition:border-color var(--duration-quick) var(--ease-smooth-out), background var(--duration-quick) var(--ease-smooth-out), transform var(--duration-quick) var(--ease-smooth-out)}.cave-opt:hover:not(:disabled){transform:translate(2px)}.cave-opt-mark[hidden]{display:none}.cave-opt-mark{opacity:0;transition:opacity var(--duration-fast) var(--ease-bounce), transform var(--duration-fast) var(--ease-bounce);flex-shrink:0;margin-left:auto;display:inline-flex;transform:scale(.6)}.cave-opt.is-correct .cave-opt-mark,.cave-opt.is-wrong .cave-opt-mark{opacity:1;transform:scale(1)}.cave-opt.is-correct .cave-opt-mark{color:var(--ok)}.cave-opt.is-wrong .cave-opt-mark{color:var(--bad)}.cave-q.is-shaking{animation:.28s both cave-shake}@keyframes cave-shake{0%{animation-timing-function:var(--ease-smooth-out);transform:translate(0)}25%{transform:translateX(calc(var(--shake-distance) * -1));animation-timing-function:var(--ease-smooth-out)}50%{transform:translateX(var(--shake-distance));animation-timing-function:var(--ease-smooth-out)}75%{transform:translateX(calc(var(--shake-overshoot) * -1));animation-timing-function:var(--ease-smooth-out)}to{transform:translate(0)}}.cave-explain{opacity:0;transition:grid-template-rows var(--duration-fast) var(--ease-smooth-out), opacity var(--duration-fast) var(--ease-smooth-out), margin-top var(--duration-fast) var(--ease-smooth-out), padding var(--duration-fast) var(--ease-smooth-out), border-color var(--duration-fast) var(--ease-smooth-out);border-left-color:#0000;grid-template-rows:0fr;margin-top:0;padding-top:0;padding-bottom:0;display:grid}.cave-explain>*{overflow:hidden}.cave-explain.is-open{border-left-color:var(--ink-300);opacity:1;grid-template-rows:1fr;margin-top:14px;padding-top:13px;padding-bottom:13px}@media print{.cave-explain{border-left-color:var(--ink-300);opacity:1;grid-template-rows:1fr;margin-top:14px;padding-top:13px;padding-bottom:13px}}.cave-done button{transition:background var(--duration-quick) var(--ease-smooth-out), color var(--duration-quick) var(--ease-smooth-out), border-color var(--duration-quick) var(--ease-smooth-out);align-items:center;gap:8px;display:inline-flex}.cave-done-mark{transform-origin:50%;display:none}.cave-done button.is-done .cave-done-mark{animation:cave-check-in var(--check-dur) var(--ease-smooth-out) both;display:inline-flex}.cave-done button.is-done .cave-done-mark path{stroke-dasharray:24;stroke-dashoffset:24px;animation:cave-check-draw var(--check-path-dur) var(--ease-smooth-out) var(--check-path-delay) forwards}@keyframes cave-check-in{0%{opacity:0;transform:rotate(var(--check-rotate-from)) scale(.7)}to{opacity:1;transform:none}}@keyframes cave-check-draw{to{stroke-dashoffset:0}}.cave-pager a{display:block}.cave-pager .mono-label{align-items:center;gap:6px;display:flex}.cave-pager .cave-pager-next .mono-label{justify-content:flex-end}.cave-pager .mono-label svg{transition:transform var(--duration-fast) var(--ease-smooth-out)}.cave-pager a:hover .mono-label svg{transform:translate(-3px)}.cave-pager a.cave-pager-next:hover .mono-label svg{transform:translate(3px)}.cave-card{transition:background var(--duration-fast) var(--ease-smooth-out), transform var(--duration-fast) var(--ease-smooth-out)}.cave-card:hover{transform:translateY(-2px)}.cave-card-go{color:var(--ink-300);transition:transform var(--duration-fast) var(--ease-smooth-out), color var(--duration-fast) var(--ease-smooth-out);margin-left:auto}.cave-card:hover .cave-card-go{color:var(--accent);transform:translate(3px)}.cave-source a svg{vertical-align:-1px;color:var(--ink-300);transition:color var(--duration-quick) var(--ease-smooth-out);margin-left:4px;display:inline-block}.cave-source a:hover svg{color:var(--accent)}.cave-railbtn{transition:border-color var(--duration-quick) var(--ease-smooth-out), background var(--duration-quick) var(--ease-smooth-out)}.cave-railbtn:hover{border-color:var(--ink-400)}.cave-scrim{opacity:0;transition:opacity var(--duration-fast) var(--ease-smooth-out)}.cave-scrim.is-open{opacity:1}@media (prefers-reduced-motion:reduce){.cave-eyebrow,.cave-h1,.cave-lede,.cave-meta,.cave-q.is-shaking,.cave-done button.is-done .cave-done-mark,.cave-done button.is-done .cave-done-mark path{animation:none}.cave-done button.is-done .cave-done-mark path{stroke-dashoffset:0}.cave-card:hover,.cave-opt:hover:not(:disabled),.cave-pager a:hover .mono-label svg,.cave-card:hover .cave-card-go,.cave-video-frame>button:hover .cave-video-play{transform:none}::view-transition-old(root),::view-transition-new(root){animation:none}}