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figcaption{background:#eee;color:#111}.code pre{white-space:pre-wrap}.code .kw,.code .str{color:#111}.cover-art{transform:none}.lab{box-shadow:none}a{color:inherit}.code figcaption a{display:none}}
/* Guided lecture/practice additions */
.action-card{border:2px solid var(--ink);margin:24px 0 30px;background:#fff;box-shadow:4px 4px 0 #d4e8f5}.action-title{background:var(--ink);color:#fff;padding:11px 17px;font:600 11px var(--mono);letter-spacing:.08em;text-transform:uppercase}.action-card dl{margin:0}.action-card dl>div{display:grid;grid-template-columns:105px 1fr;gap:15px;padding:13px 17px;border-bottom:1px solid var(--line)}.action-card dl>div:last-child{border:0;background:#edf6f9}.action-card dt{font:600 10px/1.8 var(--mono);text-transform:uppercase;color:var(--blue)}.action-card dd{margin:0;font-size:13px;line-height:1.8}.editor-guide{border:2px solid var(--ink);margin:28px 0;background:#f0f5f8;font-size:12px}.editor-guide>.eyebrow{display:block;padding:13px}.editor-toolbar{background:var(--ink);color:white;padding:12px 16px}.editor-toolbar span{display:block;color:var(--sky)}.editor-body{display:grid;grid-template-columns:160px 1fr;min-height:170px}.editor-explorer{border-right:1px solid var(--line);padding:15px;display:flex;flex-direction:column;gap:10px;font-family:var(--mono);font-size:11px}.editor-explorer small{color:var(--muted)}.editor-command{padding:18px}.editor-command code,.editor-terminal code{display:block;border:1px solid var(--blue);background:white;padding:10px;margin-top:10px;font:12px/1.7 var(--mono);overflow-wrap:anywhere}.editor-command p{font-size:12px;margin:12px 0 0}.editor-terminal{border-top:1px solid var(--line);padding:15px}.evidence{margin:28px 0;border:1px solid var(--ink);background:#f4f7fa}.evidence img{display:block;width:100%;height:auto}.evidence figcaption{padding:15px 18px;font-size:11px;color:var(--muted)}.evidence figcaption>b{color:var(--blue);font:500 10px var(--mono)}.evidence figcaption p{font-size:12px;margin:8px 0}.lesson-controls{display:flex;gap:14px;align-items:center;flex-wrap:wrap;margin:24px 0}.lesson-controls>span{font-size:11px;color:var(--muted)}#step-controls{position:sticky;top:4px;z-index:5;background:var(--page);border:2px solid var(--ink);padding:10px;display:flex;justify-content:space-between;align-items:center;gap:12px;box-shadow:3px 3px 0 var(--sky)}#step-controls[hidden],[hidden]{display:none!important}#step-status{font:500 11px/1.6 var(--mono)}#step-controls button:disabled{opacity:.35;cursor:default}.lecture-mode article>section{margin-top:28px}.lecture-mode .local-toc{margin-bottom:20px}.lecture-mode .local-toc a[aria-current=step]{color:var(--blue);font-weight:700}@media(max-width:580px){.action-card dl>div{grid-template-columns:1fr;gap:3px;padding:12px 14px}.editor-body{grid-template-columns:1fr}.editor-explorer{border-right:0;border-bottom:1px solid var(--line)}#step-status{font-size:9px}#step-controls button{font-size:10px;padding:7px 9px}.lesson-controls button{width:100%}}@media print{.lesson-controls,#step-controls{display:none!important}article>section[hidden]{display:block!important}.action-card,.evidence{break-inside:avoid}}
article ul{padding-left:22px;margin:0 0 18px}article li{font-size:15px;line-height:1.85;margin-bottom:10px}article h3{font:700 18px/1.4 Georgia,serif;margin:30px 0 10px}
.pick{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:18px}.pick button{font:11px var(--mono);padding:9px 12px}
.install-map{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.im-col{border:1px solid var(--line);background:var(--page);padding:15px;text-align:center;transition:border-color .25s,background .25s,opacity .25s}
.im-col b{display:block;font:500 13px var(--mono)}.im-col small{display:block;color:var(--muted);font-size:11px;margin:5px 0 14px}
.im-chip{display:inline-block;border:1px solid var(--ink);background:var(--ink);color:var(--sky);font:500 11px var(--mono);padding:6px 14px;opacity:0;transform:translateY(-10px);transition:opacity .3s,transform .3s}
.install-map[data-mode=m] .im-col[data-env=venv]{border-color:var(--blue);background:#e6f1f8}
.install-map[data-mode=m] .im-col[data-env=venv] .im-chip{opacity:1;transform:none;animation:chip-drop .45s ease-out}
.install-map[data-mode=m] .im-col[data-env=base]{opacity:.45}
.install-map[data-mode=bare] .im-col{border-style:dashed;border-color:var(--muted)}
.install-map[data-mode=bare] .im-chip{opacity:1;transform:none;animation:chip-blink 1.6s ease-in-out infinite}
.install-map[data-mode=bare] .im-chip::after{content:' ?';color:#ffd28a}
.run-map{border:1px solid var(--line);background:var(--page);padding:15px;font:12px/2.1 var(--mono)}
.rm-line{padding:4px 8px;border-left:3px solid transparent;transition:background .25s,border-color .25s,color .25s}
.rm-line em{font-style:normal;color:var(--muted);font-size:11px}
.rm-line[data-start]{border-left-color:var(--blue);background:#e6f1f8;animation:chip-drop .35s ease-out}
.rm-line[data-start] em{color:var(--blue)}
.rm-line[data-hidden]{opacity:.4;text-decoration:line-through}
@keyframes chip-drop{from{opacity:0;transform:translateY(-10px)}to{opacity:1;transform:none}}
@keyframes chip-blink{0%,100%{opacity:1}50%{opacity:.35}}
.reveal{opacity:0;transform:translateY(14px)}.reveal.seen{opacity:1;transform:none;transition:opacity .5s ease-out,transform .5s ease-out}
@media(max-width:580px){.install-map{grid-template-columns:1fr}.run-map{font-size:11px}.pick button{width:100%}}
@media(prefers-reduced-motion:reduce){.reveal{opacity:1;transform:none}}
@media print{.reveal{opacity:1!important;transform:none!important}}
.name-map{display:grid;gap:8px;border:1px solid var(--line);background:var(--page);padding:15px}
.nm-row{display:grid;grid-template-columns:120px 1fr;gap:14px;align-items:baseline;padding:8px 10px;border-left:3px solid transparent}
.nm-row span{font:11px var(--mono);color:var(--muted);text-transform:uppercase;letter-spacing:1px}
.nm-row b{font:500 14px var(--mono)}
.name-map[data-mode=run] .nm-row{border-left-color:var(--blue);background:#e6f1f8}
.name-map[data-mode=run] .nm-row b{color:var(--ink);animation:chip-drop .35s ease-out}
.name-map[data-mode=import] .nm-row{border-left-color:var(--muted);background:#f1f2f4}
.name-map[data-mode=import] .nm-row b{color:var(--muted);animation:chip-drop .35s ease-out}
@media(max-width:580px){.nm-row{grid-template-columns:1fr;gap:2px}}
.imp-map,.dep-map{border:1px solid var(--line);background:var(--page);padding:15px}
.imp-row{display:grid;grid-template-columns:150px 1fr;gap:14px;align-items:baseline;padding:8px 10px;border-left:3px solid var(--blue);background:#e6f1f8;margin-bottom:8px}
.imp-row span{font:11px var(--mono);color:var(--muted);text-transform:uppercase;letter-spacing:1px}
.imp-row b{font:500 13px var(--mono);overflow-wrap:anywhere;animation:chip-drop .35s ease-out}
.dep-map{display:grid;gap:10px;justify-items:center;text-align:center}
.dep-node{border:1px solid var(--ink);background:#e6f1f8;padding:10px 16px;min-width:210px;transition:background .25s,border-color .25s}
.dep-node b{display:block;font:500 12px var(--mono)}.dep-node small{color:var(--muted);font-size:11px}
.dep-pair{display:flex;gap:12px;flex-wrap:wrap;justify-content:center}
.dep-arrows{display:grid;gap:2px}
.dep-arrows i{font-style:normal;font:11px var(--mono);color:var(--blue);letter-spacing:1px;animation:chip-drop .35s ease-out}
.dep-map[data-mode=bad] .dep-node{border-color:#b4453c;background:#fbeceb}
.dep-map[data-mode=bad] .dep-arrows i{color:#b4453c}
.dep-map[data-mode=bad] .dep-arrows i[data-arrow=up]{animation:chip-blink 1.6s ease-in-out infinite}
@media(max-width:580px){.imp-row{grid-template-columns:1fr;gap:2px}.dep-node{min-width:0;width:100%}}

/* Переключатель языка: Python / Go. Скрытая ветка не удаляется из разметки. */
.lang-switch{border:1px solid var(--ink);background:var(--page);padding:12px 13px;margin-bottom:18px;box-shadow:3px 3px 0 var(--blue)}
.lang-switch .eyebrow{display:block}
.lang-switch>div{display:flex;gap:5px;margin:9px 0 9px}
.lang-switch button{flex:1;padding:9px 6px;font-size:11px}
.lang-switch p{margin:0;font:500 10px/1.55 var(--mono);color:var(--muted)}
:root[data-lang=py] [data-lang=go],:root[data-lang=go] [data-lang=py]{display:none!important}
.lang-note{border-left:3px solid var(--blue);background:#2d7fc10d;padding:12px 15px;margin:26px 0;font-size:14px}
.lang-note b{display:block;font:600 11px var(--mono);letter-spacing:.06em;text-transform:uppercase;margin-bottom:5px}
.lang-note p{margin:0}
@media (max-width:850px){.lang-switch{margin-bottom:14px}}
.lang-hint{border:1px dashed var(--blue);background:var(--page);padding:13px 16px;font-size:14px}
.lang-hint b{font:700 13px var(--mono)}