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.95rem,1.32rem);line-height:1.56}.lesson-rail{position:relative;display:grid;flex:1;gap:10px;min-height:0;overflow:auto;padding:2px 2px 8px 20px;scrollbar-color:var(--line-2) transparent;scrollbar-width:thin}.lesson-rail:before{position:absolute;top:16px;bottom:20px;left:8px;width:1px;background:var(--line-2);content:""}.explanation-row{position:relative;display:grid;grid-template-columns:112px minmax(0,1fr);align-items:stretch;min-height:86px;padding:0;overflow:visible;border:1px solid var(--line);border-radius:12px;background:var(--paper);color:var(--ink);cursor:pointer;text-align:left;transition:border-color .25s var(--ease),background .25s var(--ease),transform .25s var(--ease)}.explanation-row:hover{border-color:var(--line-2);transform:translate(2px)}.explanation-row.selected{border-color:var(--brand);background:color-mix(in oklab,var(--brand) 8%,var(--paper))}.rail-dot{position:absolute;top:50%;left:-20px;z-index:2;width:12px;height:12px;border:2px solid 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p{color:var(--muted);font-family:var(--mono);font-size:.78rem}.skeleton{border-radius:12px;background:linear-gradient(90deg,var(--paper-2) 25%,var(--paper) 50%,var(--paper-2) 75%);background-size:200% 100%;animation:shimmer 1.4s infinite}.summary-skeleton{height:98px}.row-skeleton{height:86px;margin-left:20px}.row-skeleton.short{width:82%}.site-footer{display:flex;flex-wrap:wrap;align-items:center;gap:.45rem .15rem;padding:1.6rem var(--pad) 2.2rem;border-top:1px solid var(--line);background:color-mix(in oklab,var(--paper-2) 70%,transparent);color:var(--muted);font-family:var(--mono);font-size:.74rem}.site-footer a{color:var(--ink-soft);text-decoration:none}.site-footer a:hover{color:var(--brand)}.footer-sep{margin:0 .45rem;color:var(--line-2)}@keyframes spin{to{transform:rotate(360deg)}}@keyframes blink{50%{opacity:0}}@keyframes shimmer{to{background-position:-200% 0}}@media(max-width:930px){main{padding-bottom:60px}.intro-points{grid-template-columns:1fr}.readout{grid-template-rows:auto auto}.workspace{grid-template-columns:1fr}.editor-column{padding-right:1.15rem}.explanation-column{border-top:1px solid var(--line);border-left:0}.editor-frame{min-height:380px;height:54vh}.lesson-rail{max-height:none;overflow:visible}}@media(max-width:600px){.site-header{height:54px;padding:0 18px}main{padding:22px 18px 44px}.intro{margin-bottom:24px}.intro h1{font-size:2.3rem}.lede{max-width:340px;font-size:1.05rem;line-height:1.5}.editor-frame{min-height:350px;height:54vh}.editor-body{grid-template-columns:42px minmax(0,1fr)}.code-backdrop,.code-window textarea{padding-right:12px;padding-left:12px;font-size:13px}.code-line{margin:0 -12px;padding:0 12px}.editor-actions{align-items:flex-start;flex-direction:column;gap:10px}.primary-button,.upload-button{width:100%}.program-summary{padding:17px}.explanation-row{grid-template-columns:1fr}.line-label{padding:12px 15px 7px;border-right:0}.explanation-sentence{padding:4px 15px 15px}}@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}