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@media(max-width:760px){.pilot-wrap{width:calc(100% - 36px)}.preview-bar{padding:8px 18px;font-size:12px}.preview-bar span{font-size:11px}.pilot-header>.pilot-wrap{height:85px;gap:15px}.brand-name{font-size:1.15rem}.brand-name>span{font-size:.6rem}.pilot-header nav{gap:10px;font-size:13px}.pilot-header nav a:not([aria-current]){display:none}.pilot-crumb{font-size:12px;margin-top:22px}.lesson-heading{padding:12px 0 25px}.lesson-heading .eyebrow{font-size:12px}.lesson-heading h1{margin:15px 0 20px}.heading-bottom{flex-wrap:wrap;gap:12px;font-size:13px}.lesson-layout{display:block;margin:28px 0 40px}.lesson-aside{display:none}.task-meta{gap:15px;font-size:13px}.attempt-panel{padding:22px 18px}.lesson-main h2{font-size:21px}.lesson-disclosure>summary{font-size:17px;padding:21px 0}.disclosure-body{font-size:16px}.proof-step{grid-template-columns:22px minmax(0,1fr);gap:8px}.katex{font-size:1.06em}.lesson-figure{padding:16px 8px}.lesson-figure svg{min-width:0}.lesson-figure{overflow-x:auto}.lesson-figure figcaption,.diagram-legend{min-width:0;position:sticky;left:0}.pilot-footer{gap:20px;font-size:12px}.pilot-footer span{max-width:170px}.pilot-grid{display:block}.pilot-index-head{padding:35px 0}.pilot-card h2{font-size:22px}.index-counts{gap:12px;font-size:13px}}
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.diagram-toolbar{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:18px;font-size:12px;color:var(--study-muted)}
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.diagram-dialog{border:1px solid var(--study-line);border-radius:6px;max-width:min(1120px,96vw);width:1120px;max-height:92vh;padding:20px 24px;margin:auto;color:var(--ink);background:#fff;overflow:auto}
.diagram-dialog::backdrop{background:rgba(19,35,55,.55)}
.diagram-dialog-head{display:flex;align-items:center;justify-content:space-between;gap:20px;font-size:16px}
.diagram-dialog-help{font-size:12px;color:var(--study-muted)}
.diagram-dialog .lesson-figure{margin:16px 0 0}
.diagram-dialog .diagram-canvas{overflow:auto}
.diagram-dialog .diagram-canvas>svg{min-width:720px}
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.math-display .katex-display{width:max-content;min-width:100%}

/* Teaching revision 2: the same study surface, with explicit intermediate steps. */
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.proof-step{padding:22px 0}.proof-step+.proof-step{border-top:1px solid #edf0f5}
.proof-step .lesson-figure{margin:22px 0 4px}.proof-step p{margin:0 0 13px}
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.lesson-table-wrap{overflow-x:auto;margin:20px 0}.lesson-table{width:100%;border-collapse:collapse;font-size:15px;line-height:1.6}.lesson-table th,.lesson-table td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--study-line);vertical-align:top}.lesson-table th{background:var(--study-soft);font-weight:500}.lesson-table td p{margin:0}
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.interactive-disclosure{border:1px solid var(--study-line);padding:0 16px;margin-top:22px;background:#fcfdff}
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/* Keep accessible MathML inside the horizontally scrollable table container. */
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.score-note{font-size:12px;line-height:1.6;margin-top:12px;color:var(--study-muted)}

.math-variant[hidden]{display:none!important}.math-variant{max-width:none}.math-display{position:relative}.math-display .katex-html{display:inline-block}.math-display .katex-display{margin:.35em 0}

/* The v2 figures keep a readable label size on narrow study columns. A local
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.diagram-canvas{max-width:100%;overflow-x:auto;overscroll-behavior-x:contain}
@media(max-width:760px){.lesson-figure .diagram-canvas>svg{min-width:0}.lesson-figure{overflow:hidden}.diagram-dialog .diagram-canvas:after{content:none}}
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/* Keep short mathematical units intact when prose wraps on a phone. */
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.diagram-enlarge,.diagram-close{min-height:44px}
.time-comparison{font:16px/1.5 var(--sans);padding:8px 0;min-width:0}
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.time-comparison-track{height:12px;background:#e8edf0;width:100%;margin:12px 0}
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/* Full-scene overview; enlarged outer SVG pans without clipping nested source figures. */
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/* One local viewport for wide formulas; preserve normal text size. */
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.math-display[data-math-overflow=true]::after{content:"↔ Прокрути формулу";display:block;position:sticky;left:0;width:fit-content;font:400 12px/1.6 var(--sans);color:var(--study-muted);padding-top:4px}

/* Owner acceptance correction: these 77 lessons keep the full proof column.
   The shared research flex layout must not shrink a formula-only step to its contents.
   Wide formulas retain native scrolling and an accessible label, without a text callout. */
:is([data-problem-id^="phystech-2025-2026-physics-"][data-problem-id*="-round-"],[data-problem-id^="phystech-2025-2026-9-9-"]) .proof-step>div{flex:1;min-width:0}
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/* Sequences can now live inside a proof step; do not inherit its full-bleed margin twice. */
.academy-factory .proof-step .learning-sequence .lesson-figure{margin-left:0;width:100%;max-width:100%;box-sizing:border-box}

.ultra-game{margin:1.1rem 0;padding:1rem;border:1px solid #cad8de;border-radius:14px;background:#f8fbfc;min-width:0;box-sizing:border-box}.ultra-game h4{margin-top:0}.ultra-game p{max-width:70ch}.ultra-board-wrap{max-width:380px}.ultra-board{border-collapse:collapse;table-layout:fixed;width:100%;max-width:380px;background:white;font-variant-numeric:tabular-nums}.ultra-board td{position:relative;width:16.666%;aspect-ratio:1;text-align:center;border:1px solid #9aafb9;padding:.55em .15em;font-size:clamp(16px,4.9vw,22px);color:#17323e}.ultra-board tr:nth-child(2n) td{border-bottom:3px solid #48616c}.ultra-board tr:first-child td{border-top:3px solid #48616c}.ultra-board td:nth-child(2n){border-right:3px solid #48616c}.ultra-board td:first-child{border-left:3px solid #48616c}.ultra-board .visited{background:#d7ede5}.ultra-board .current{background:#f8dfa3;font-weight:700}.ultra-board .next{outline:3px solid #26634d;outline-offset:-4px;font-weight:700}.ultra-dot{position:absolute;font-size:8px;bottom:1px;left:50%;transform:translateX(-50%)}.ultra-legend{font-size:.9rem;color:#536b77}.ultra-actions,.ultra-card-choices{display:flex;flex-wrap:wrap;gap:.5rem;margin:.8rem 0}.ultra-game button,.ultra-game select{font:inherit;min-height:44px;max-width:100%;border:1px solid #839aa6;border-radius:8px;background:white;color:#173e4d;padding:.55rem .7rem;box-sizing:border-box}.ultra-game button:not(:disabled){cursor:pointer}.ultra-game button:disabled{opacity:.5;cursor:default}.ultra-game button:focus-visible,.ultra-game select:focus-visible{outline:3px solid #257ac3;outline-offset:2px}.ultra-game .ultra-card{min-width:56px;min-height:72px;font-size:1.5rem;font-weight:700}.ultra-deal-label{display:grid;gap:.35rem;font-weight:600}.ultra-game select{width:100%;font-weight:400}.ultra-card-feedback{min-height:1.4em;color:#254e3e}.ultra-card-state{border-top:1px solid #d5e0e5;margin-top:.8rem;padding-top:.2rem}.ultra-game [hidden]{display:none!important}@media(max-width:390px){.ultra-game{padding:.65rem}.ultra-actions button{flex:1 1 auto}.ultra-board td{padding:.45em .1em}}

.learning-sequence{margin:1.8rem 0;padding:1.25rem 0;border-top:1px solid #ced8e3;border-bottom:1px solid #ced8e3;min-width:0}.learning-sequence h3{margin-top:0}.learning-sequence-choices,.learning-sequence-actions{display:flex;flex-wrap:wrap;gap:.55rem;margin:.8rem 0}.learning-sequence button{font:inherit;font-size:.9rem;line-height:1.45;max-width:100%;text-align:left;background:#f7f9fc;border:1px solid #b8c9d8;border-radius:5px;color:#233d56;padding:.55rem .8rem;cursor:pointer}.learning-sequence button[aria-pressed=true]{background:#234f78;color:white;border-color:#234f78}.learning-sequence button:disabled{opacity:.45;cursor:default}.learning-sequence button:focus-visible{outline:3px solid #ad843f;outline-offset:3px}.learning-sequence-status{font-size:.88rem;color:#596b7d}.learning-sequence-states>section{min-width:0}.learning-sequence-states>section[hidden]{display:none}.learning-sequence .lesson-figure{margin:1rem 0}.learning-sequence-states h4{font-size:1.08rem;line-height:1.5}.learning-sequence .katex{font-size:1em}@media(max-width:420px){.learning-sequence-choices{display:grid;grid-template-columns:minmax(0,1fr)}.learning-sequence-actions button{flex:1 1 42%}}

.spatial-lesson [data-spatial-state][aria-pressed=true]{background:#234f78;color:white;border-color:#234f78}.spatial-lesson .q3d-static-reference{overflow:auto}.spatial-lesson .q3d-static-reference svg{width:100%;min-width:0;height:auto;display:block}

/* A sequence inside a proof step owns its width; do not inherit the direct figure outdent. */
.proof-step .learning-sequence .lesson-figure{margin-left:0;width:100%;max-width:100%;box-sizing:border-box}

.archive-condition .math-display{font-size:17px}.academy-lesson .lesson-heading{margin-top:20px}