:root{--bg:#0e151d;--card:#17212d;--input:#111b25;--line:#304252;--text:#edf4f3;--muted:#abbcc7;--accent:#a6efb9;--ink:#102b20;--error:#ffb3ac;--shadow:0 18px 60px #0002;color-scheme:dark}*{box-sizing:border-box}body{margin:0;background:radial-gradient(ellipse at 90% 0%,#21443b55,transparent 45%),var(--bg);color:var(--text);font:15px/1.6 system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif}body.light{--bg:#f3f7f4;--card:#fff;--input:#f7faf8;--line:#ccdbd2;--text:#162d27;--muted:#52695e;--accent:#176a42;--ink:#fff;--error:#9a2b26;color-scheme:light}.app{max-width:1240px;padding:36px 44px 0;margin:auto}.header{display:flex;align-items:center;justify-content:space-between;gap:20px;padding-bottom:26px;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:12px;color:var(--text);text-decoration:none}.brand-cell{width:47px;height:53px;border:1px solid var(--accent);border-radius:9px 9px 18px 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button.done{background:var(--accent);color:var(--ink);border-color:var(--accent)}.save-note{font-size:10px;color:var(--muted);margin-top:20px}.result-number{font-size:62px;color:var(--accent);line-height:1.3;letter-spacing:-3px;margin:20px 0}.result .muted{font-size:13px}.review-item{padding:16px;border:1px solid var(--line);border-left:3px solid var(--accent);border-radius:9px;margin:14px 0;font-size:12px;overflow-wrap:anywhere}.review-item.wrong{border-left-color:var(--error)}.review-item summary{cursor:pointer;font-weight:600}.review-item p{white-space:pre-wrap}.review-item small{font-size:9px;color:var(--muted)}dialog{color:var(--text);background:var(--bg);border:1px solid var(--line);border-radius:20px;padding:26px;width:min(740px,calc(100vw - 24px));max-height:calc(100dvh - 32px);box-shadow:0 30px 100px #0008}dialog::backdrop{background:#061018c9;backdrop-filter:blur(5px)}.keyboard-dialog{width:min(930px,calc(100vw - 24px))}.dialog-header{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:20px}.dialog-header .eyebrow{font-size:8px;margin-bottom:7px}.dialog-header h2{font-size:23px;margin:0}.keyboard-toolbar{display:flex;justify-content:space-between;align-items:center;font-size:10px;color:var(--muted);gap:15px;margin-top:8px}.keyboard-toolbar button{min-height:32px;padding:6px 10px;font-size:11px}.keyboard-dialog h3{font-size:12px;margin:20px 0 10px}.keyboard-note{font-size:10px;color:var(--muted);margin:0 0 10px}.periodic-scroll{max-width:100%;overflow-x:auto;padding:3px 1px 9px}.periodic-table{display:grid;grid-template-columns:repeat(18,minmax(32px,1fr));grid-template-rows:repeat(8,42px);gap:4px;min-width:660px}.element-key{min-height:0;font:600 13px ui-monospace,monospace;position:relative;padding:10px 3px 3px;border-radius:5px;background:var(--card)}.element-key small{position:absolute;top:2px;left:4px;font-size:7px;font-weight:400;color:var(--muted)}.element-key.nonmetal{color:var(--accent);border-color:color-mix(in srgb,var(--accent) 35%,var(--line))}.element-key.transition{background:color-mix(in srgb,var(--accent) 4%,var(--card))}.key-row{display:flex;gap:6px;flex-wrap:wrap}.key-row button{min-width:42px;padding:7px 10px;min-height:39px;font-size:17px}.dialog-bottom{border-top:1px solid var(--line);padding-top:18px;margin-top:24px;display:flex;justify-content:space-between;align-items:center;gap:15px}.dialog-bottom>span{font-size:10px;color:var(--muted)}.dialog-bottom button{font-size:12px}.history-row{display:flex;justify-content:space-between;gap:15px;padding:15px 0;border-bottom:1px solid var(--line);font-size:13px}.history-row small{display:block;color:var(--muted);font-size:10px}.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%)}[hidden]{display:none!important}@media(max-width:950px){.app{padding:26px 24px 0}.workspace{gap:16px;grid-template-columns:minmax(0,1.2fr) minmax(0,1fr)}.panel{padding:23px}.hero-formula{transform:scale(.88)}.start-row{align-items:stretch;flex-direction:column}.start-button{width:100%}.start-row>div{grid-template-columns:auto 72px 1fr}.start-row small{grid-column:3;margin:0 0 0 8px}.field legend span{display:block;margin:2px 0 0}.level-chips button{font-size:10px}}@media(max-width:680px){.app{padding:20px 16px 0}.header{gap:10px;padding-bottom:20px}.brand strong{font-size:27px}.brand-cell{height:45px;width:39px}.brand-cell b{font-size:24px}.brand>span>small{font-size:6px;letter-spacing:1px}.brand{gap:8px}nav{gap:5px}nav .quiet{font-size:0;width:35px;padding:0}nav .quiet:before{content:'↗';font-size:21px}.icon-button{width:37px;height:37px;min-height:37px;font-size:22px}.hero{display:block;padding:34px 0 30px}.hero-formula{display:none}h1{font-size:39px;letter-spacing:-1.6px}.lead{font-size:13px}.eyebrow{font-size:9px}.hero-tags span{font-size:9px}.workspace{grid-template-columns:1fr;gap:18px}.panel{padding:23px;border-radius:17px}.field legend span{display:inline;margin-left:7px}.level-chips button{font-size:11px}.start-row{flex-direction:column}.start-row>div{grid-template-columns:auto 72px 1fr}.right-column{gap:18px}.chain-diagram{margin:24px 0}.side-note{display:none}.topic-list{max-height:220px}.topic-option{font-size:12px;min-height:43px}.text-button{font-size:11px;min-height:36px}footer{margin-top:28px;flex-direction:column;align-items:flex-start;gap:6px;font-size:10px}.keyboard-dialog{padding:16px;max-height:calc(100dvh - 16px)}.dialog-header h2{font-size:20px}.keyboard-toolbar>span{max-width:50%}.dialog-bottom{align-items:stretch;flex-direction:column}.quiz h2{font-size:20px}.question-nav button{width:32px;min-height:32px}.answer-option{font-size:14px}.quiz-actions button{min-height:47px}.periodic-table{grid-template-rows:repeat(8,44px)}input,select{font-size:16px}.start-row select{font-size:16px}.scratch textarea{font-size:16px}.key-row button{min-width:43px;min-height:43px}}@media(prefers-reduced-motion:no-preference){button{transition:background .16s,border-color .16s}dialog[open]{animation:appear .15s ease-out}@keyframes appear{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}}
/* 1.0.1: chemical typography and the traditional eight-group short table. */
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#chainPlayer{width:min(1120px,calc(100vw - 20px))}.chain-art{margin:18px 0 10px;border-radius:12px;border:1px solid var(--line);overflow:auto;background:#fff}.chain-art img{display:block;width:100%;height:auto}.chain-art.zoom img{width:1500px;max-width:none}#chainPlayer #chainTaskPrompt{font-size:13px;color:var(--muted)}#chainPlayer #chainAnswer li{margin:16px 0;overflow-wrap:anywhere}#chainPlayer #chainAnswer li p{font-size:12px}#chainSummary button{margin:8px}.chain-solution{font-size:18px}#chainBranches button{font-size:12px}.chains .field{margin:18px 0}.chains .start-row>button{font-size:12px}
.calc-categories{border:0;padding:0;margin:20px 0 10px;display:grid;grid-template-columns:1fr 1fr;gap:9px}.calc-category{display:flex;align-items:center;gap:9px;padding:11px;border:1px solid var(--line);border-radius:9px;font-size:12px;cursor:pointer;background:var(--input)}.calc-category:has(:checked){border-color:var(--accent)}.calc-category input{width:18px;height:18px;min-height:18px;accent-color:var(--accent);margin:0;flex:0 0 18px}.reaction-kinds{display:grid;gap:10px}.reaction-kinds button{display:flex;text-align:left;justify-content:space-between;gap:10px;font-size:13px}.reaction-kinds button span{color:var(--accent);white-space:nowrap}#extraPlayer{width:min(1000px,calc(100vw - 20px))}#extraPrompt{font-size:19px;line-height:1.65;white-space:pre-wrap;overflow-wrap:anywhere}#extraFeedback{white-space:normal}#extraFeedback p,#extraFeedback li{white-space:pre-wrap}#extraFeedback li{margin:10px 0}.oxid-atom{min-width:1.15em;display:inline-flex;flex-direction:column;align-items:center;vertical-align:baseline;position:relative;margin-top:1em}.oxid-state{position:absolute;bottom:100%;font-size:.65em;line-height:1.1;white-space:nowrap}.redox-equation{font-size:20px;line-height:2.2;overflow-wrap:anywhere;margin:14px 0}.electron-balance{border-collapse:collapse;width:auto;margin:12px 0}.electron-balance td{padding:8px 18px;white-space:nowrap;font-size:18px}.electron-balance td:last-child{border-left:1px solid var(--accent);text-align:center;padding:8px 20px}.balance-scroll{max-width:100%;overflow:auto}#extraSummary .review-item h3{font-size:16px}#extraFeedback h3{margin-top:18px;font-size:17px}#extraFeedback h3:first-child{margin-top:0}@media(max-width:680px){.calc-categories{grid-template-columns:1fr}.calc-category{min-height:45px;font-size:14px}.redox-equation{font-size:18px}.electron-balance td{font-size:16px;padding:8px 10px}#extraPrompt{font-size:17px}}
/* Settings and teacher worksheets */
[hidden]{display:none!important}.setting-options{display:grid;gap:9px}.setting-options label{display:flex;gap:12px;align-items:center;padding:12px;background:var(--input);border:1px solid var(--line);border-radius:10px;cursor:pointer}.setting-options input{width:20px;height:20px;min-height:20px;margin:0;accent-color:var(--accent)}#settingsDialog{width:min(520px,calc(100vw - 24px))}#ambientVolume{padding:0;accent-color:var(--accent)}#teacherPanel{margin-bottom:24px;display:flex;gap:24px;align-items:center;justify-content:space-between}#teacherPanel h2{margin:0}#teacherPanel p{margin:6px 0}.teacher-add{margin-top:14px;width:100%;font-size:12px}.teacher-reactions{display:grid;gap:8px;margin-top:16px}#teacherAddCurrent,#teacherAddExtra,#teacherAddChain{margin-bottom:18px}#teacherDialog{width:min(960px,calc(100vw - 24px))}.teacher-toolbar{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-top:18px}.teacher-toolbar label{display:flex;align-items:center;gap:10px}.teacher-toolbar input{min-height:20px;width:20px;height:20px;accent-color:var(--accent)}.teacher-list{padding-left:26px;max-height:44vh;overflow:auto;margin:20px 0}.teacher-list li{padding:12px 6px;border-bottom:1px solid var(--line)}.teacher-list p{margin:4px 0;white-space:pre-wrap;overflow-wrap:anywhere}.teacher-row-actions{display:flex;gap:5px;justify-content:flex-end}.teacher-row-actions button{min-height:36px;padding:3px 12px}.empty-selection{list-style:none;color:var(--muted)}#teacherMailForm{margin-top:24px;padding-top:18px;border-top:1px solid var(--line)}#teacherToast{position:fixed;z-index:10000;bottom:20px;left:50%;transform:translateX(-50%);background:var(--accent);color:var(--ink);border-radius:12px;padding:12px 22px;box-shadow:var(--shadow);max-width:90vw;text-align:center}
body[data-display=phone] .app{max-width:480px;padding:20px 16px 0}body[data-display=phone] .workspace{grid-template-columns:1fr;gap:18px}body[data-display=phone] .hero{display:block;padding:32px 0}body[data-display=phone] .hero-formula{display:none}body[data-display=phone] h1{font-size:39px;letter-spacing:-1.6px}body[data-display=phone] .panel{padding:23px}body[data-display=phone] .calc-categories{grid-template-columns:1fr}body[data-display=phone] .start-row{flex-direction:column}body[data-display=phone] .start-row>div{grid-template-columns:auto 72px 1fr}body[data-display=phone] #teacherPanel{align-items:stretch;flex-direction:column}body[data-display=phone] .lead{font-size:13px}body[data-display=phone] .teacher-toolbar{align-items:flex-start;flex-direction:column}body[data-display=phone] .brand>span>small{font-size:6px}body[data-display=phone] .brand strong{font-size:26px}body[data-display=phone] .header{gap:10px}
body[data-display=board]{font-size:20px}body[data-display=board] .app{max-width:1800px;padding:32px 44px 0}body[data-display=board] h1{font-size:66px}body[data-display=board] h2{font-size:30px}body[data-display=board] button,body[data-display=board] select,body[data-display=board] input,body[data-display=board] textarea{font-size:20px;min-height:58px}body[data-display=board] .topic-option,body[data-display=board] .calc-category{font-size:19px;min-height:58px}body[data-display=board] .topic-list{max-height:340px}body[data-display=board] .save-note,body[data-display=board] .muted{font-size:18px}body[data-display=board] #qPrompt,body[data-display=board] #extraPrompt{font-size:30px}body[data-display=board] .quiz,body[data-display=board] dialog{padding:32px}body[data-display=board] #extraPlayer,body[data-display=board] #chainPlayer{width:min(1400px,calc(100vw - 30px))}body[data-display=board] .redox-equation,body[data-display=board] .electron-balance td{font-size:28px}body[data-display=board] input[type=radio],body[data-display=board] input[type=checkbox]{min-height:24px;width:24px;height:24px}body[data-display=board] .setting-options input{flex:0 0 24px}body[data-display=board] .icon-button{min-width:58px}body[data-display=board] .section-label{font-size:14px}body[data-display=board] .hero-tags span{font-size:15px}body[data-display=board] .question-nav button{min-width:54px}
@media(max-width:680px){#teacherPanel,.teacher-toolbar{flex-direction:column;align-items:stretch}#teacherPanel{padding:23px}body[data-display=board] .app{padding:16px}body[data-display=board] h1{font-size:42px}#teacherDialog{padding:18px}.teacher-list{padding-left:22px}.teacher-toolbar{gap:10px}}
body[data-display=phone] #extraPlayer,body[data-display=phone] #chainPlayer,body[data-display=phone] #teacherDialog,body[data-display=phone] #settingsDialog{width:min(480px,calc(100vw - 24px));padding:20px}body[data-display=phone] .keyboard-dialog{width:min(480px,calc(100vw - 24px));padding:18px}
/* Community, support and rotating quotes */
.header-actions{display:flex;gap:22px;align-items:center;flex-wrap:wrap;justify-content:flex-end}.page-tabs{display:flex;gap:5px;padding:4px;border:1px solid var(--line);border-radius:12px;background:var(--input)}.page-tabs button{border:0;background:transparent;padding:9px 14px;min-height:40px;font-size:13px}.page-tabs button.active{background:var(--accent);color:var(--ink)}.question-community{border-top:1px solid var(--line);padding-top:18px;margin-top:22px}.feedback-label{display:block;font-size:13px;color:var(--muted);margin-bottom:9px}.rating-actions{display:flex;gap:8px;flex-wrap:wrap}.rating-actions button{min-height:43px;padding:8px 14px}.rating-actions button[aria-pressed=true]{border-color:var(--accent);background:color-mix(in srgb,var(--accent) 13%,var(--input))}.comment-button{font-size:13px}.rating-status{margin:8px 0 0}.support-view{max-width:920px;margin:40px auto}.author-intro{display:flex;gap:30px;align-items:center;margin-bottom:36px}.author-intro img{width:180px;height:auto;flex:0 0 180px;border-radius:20px;object-fit:cover}.support-view h1{font-size:36px;line-height:1.15;letter-spacing:-1px}.support-view .eyebrow{margin-top:0}.support-view h2{font-size:28px}.support-links{display:grid;gap:12px;margin:28px 0}.support-links a{display:flex;gap:15px;align-items:center;color:var(--text);text-decoration:none;border:1px solid var(--line);border-radius:14px;padding:16px;background:var(--input)}.support-links a:hover,.support-links a:focus-visible{border-color:var(--accent)}.support-links a>b{margin-left:auto}.support-links strong{font-size:16px}.support-links small{display:block;font-size:13px;color:var(--muted);margin-top:4px}.support-mark{display:grid;place-items:center;flex:0 0 52px;width:52px;height:52px;border-radius:12px;font-size:28px;font-weight:800}.tbank-mark{background:#ffdd2d;color:#222}.sber-mark{background:#21a038;color:white}.telegram-mark{background:#229ed9;color:white}.support-note{border:1px solid var(--line);padding:18px;border-radius:12px;background:var(--input)}.quote-box{max-width:800px;margin:48px auto 24px;padding:26px;text-align:center;border-top:1px solid var(--line)}.quote-box blockquote{margin:0 0 12px}.quote-box blockquote p{font-size:22px;line-height:1.55;white-space:pre-line;margin:0 0 12px}.quote-box cite{font-size:14px;font-style:normal;color:var(--accent)}.quote-box>a{font-size:11px;color:var(--muted);margin-right:12px}.quote-box>.save-note{font-size:11px}.footer-actions{display:flex;gap:18px;flex-wrap:wrap}.footer-credit{white-space:nowrap}.footer-actions .text-button{font-size:12px}footer{flex-wrap:wrap;gap:14px}#communityDialog{width:min(720px,calc(100vw - 24px))}.community-context{padding:14px;border:1px solid var(--line);border-radius:10px;background:var(--input);white-space:pre-wrap}.community-context p{margin:6px 0}.community-context small{color:var(--muted);font-size:11px;overflow-wrap:anywhere}#communityForm textarea{width:100%;min-height:100px;font-size:16px}.form-status{white-space:pre-wrap;overflow-wrap:anywhere;font-size:14px}.community-honeypot{position:absolute;left:-10000px;width:1px;height:1px;overflow:hidden}#communityForm .field{margin-top:20px}#communitySubmit{margin-top:8px}
body[data-display=phone] .header{flex-wrap:wrap;justify-content:center}body[data-display=phone] .header-actions{width:100%;justify-content:space-between;gap:8px}body[data-display=phone] .page-tabs button{font-size:11px;padding:8px}body[data-display=phone] .support-view h1{font-size:27px}body[data-display=phone] .author-intro{flex-direction:column;align-items:flex-start;gap:20px}body[data-display=phone] .author-intro img{width:140px;flex-basis:auto}body[data-display=phone] .support-links strong{font-size:14px}body[data-display=phone] .quote-box blockquote p{font-size:19px}body[data-display=board] .quote-box{max-width:1200px}body[data-display=board] .quote-box blockquote p{font-size:30px}body[data-display=board] .support-view{max-width:1250px}body[data-display=board] .support-view h1{font-size:46px}body[data-display=board] .support-links strong{font-size:23px}body[data-display=board] .header-actions{gap:12px}body[data-display=board] .page-tabs button{font-size:20px}
@media(max-width:680px){.header{flex-wrap:wrap;justify-content:center}.header-actions{width:100%;justify-content:space-between;gap:8px}.page-tabs button{font-size:11px;padding:8px}.author-intro{flex-direction:column;align-items:flex-start;gap:18px}.author-intro img{width:140px;flex-basis:auto}.support-view h1{font-size:27px}.support-view h2{font-size:23px}.support-links a{padding:12px;gap:10px}.support-mark{width:42px;height:42px;flex-basis:42px;font-size:24px}.support-links strong{font-size:14px}.support-links small{font-size:11px}.quote-box{margin-top:30px;padding:22px 0}.quote-box blockquote p{font-size:19px}.footer-actions{gap:8px 20px}.footer-credit{font-size:11px}#communityDialog{padding:20px}.rating-actions .comment-button{width:100%}}
/* Consistent control alignment and compact results */
.header .icon-button{display:inline-flex;align-items:center;justify-content:center;flex:0 0 42px;width:42px;height:42px;min-height:42px;padding:8px;line-height:1}.header .icon-button svg{width:24px;height:24px}.header-actions>nav[aria-label="Инструменты"]{display:flex;align-items:center;gap:8px}.start-row{align-items:end}.start-row>div{min-width:0}.start-row>button{min-height:48px;align-self:end;white-space:normal;line-height:1.4}.calc-category{min-height:48px}.quiz-actions{display:flex;gap:10px;flex-wrap:wrap;align-items:stretch}.quiz-actions button{display:inline-flex;align-items:center;justify-content:center;line-height:1.4;text-align:center;min-height:48px;flex:1 1 190px;margin:0}.quiz-actions button:only-child{flex-grow:0}.result>h2{margin:0 0 14px}.result-number{display:flex;align-items:baseline;gap:12px;line-height:1.1;margin:12px 0 22px;letter-spacing:-2px}.result-number strong{font-size:74px;font-weight:500}.result-number>span{font-size:30px;color:var(--muted);letter-spacing:-1px}#resultActions{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}#resultActions button{width:100%;min-height:54px;white-space:normal;padding:14px 16px}#resultActions button:only-child{grid-column:1/-1}.answer-option{display:flex;align-items:flex-start;gap:12px}.answer-option input[type=radio]{width:19px;height:19px;min-height:19px;flex:0 0 19px;margin:3px 0 0}.answer-option>span{min-width:0;overflow-wrap:anywhere}.chips{align-items:center}.chips button{display:flex;align-items:center;justify-content:center;min-height:43px;line-height:1.3}.right-column .section-label{align-items:center;gap:10px;flex-wrap:wrap}.right-column .mini-pill{white-space:nowrap}.field select{min-height:46px}.result .review-item summary{overflow-wrap:anywhere;line-height:1.5}
body[data-display=phone] .start-row{align-items:stretch}body[data-display=phone] .start-row>button{align-self:stretch;width:100%}body[data-display=phone] #resultActions{grid-template-columns:1fr}body[data-display=phone] .result-number strong{font-size:64px}body[data-display=phone] .quiz-actions{display:grid;grid-template-columns:1fr}body[data-display=phone] .quiz-actions button{width:100%;min-height:48px}body[data-display=board] .header .icon-button{flex-basis:58px;width:58px;height:58px;min-height:58px}body[data-display=board] .result-number strong{font-size:100px}body[data-display=board] .result-number>span{font-size:42px}
@media(max-width:680px){.start-row{align-items:stretch}.start-row>button{align-self:stretch;width:100%}#resultActions{grid-template-columns:1fr}.quiz-actions{display:grid;grid-template-columns:1fr}.quiz-actions button{width:100%;min-height:48px}.result-number strong{font-size:64px}.result-number>span{font-size:27px}.header .icon-button{flex-basis:38px;width:38px;height:38px;min-height:38px}.header-actions{align-items:center}.result .review-item{padding:13px}.answer-option{padding:13px}}
@media(min-width:681px){.start-row{align-items:flex-start}.start-row>button{align-self:flex-start}.start-row select{min-height:48px}}
/* Study links, five-star ratings and test results. */
.star-rating{display:flex;align-items:center;gap:4px;flex-wrap:nowrap}.star-rating button{font-size:27px;line-height:1;min-width:42px;min-height:44px;padding:6px;background:transparent;border-color:transparent;color:var(--muted)}.star-rating button.filled,.star-rating button:hover,.star-rating button:focus-visible{color:var(--accent)}.star-rating button[aria-pressed=true]{border-color:var(--accent)}.rating-actions{align-items:center;flex-wrap:wrap}.task-theory-links{display:flex;flex-direction:column;align-items:flex-start;gap:7px;margin-top:18px;padding-top:15px;border-top:1px solid var(--line)}.task-theory-link{color:var(--accent);font-size:.92em;line-height:1.5;text-underline-offset:4px;overflow-wrap:anywhere}.footer-actions{flex-wrap:wrap;justify-content:center;gap:10px 18px}.footer-credit a{color:inherit;text-underline-offset:4px}
.theory-view,.leaderboard-view{margin-top:28px}.theory-heading{display:flex;align-items:center;justify-content:space-between;gap:22px}.theory-view h1,.leaderboard-view h1{font-size:32px;line-height:1.2;margin:6px 0 22px}.theory-filters{display:grid;grid-template-columns:120px minmax(0,1fr);gap:18px;margin:24px 0}.theory-filters label,.nickname-form label{display:block;margin-bottom:7px}.theory-filters input,.theory-filters select,.nickname-form input{width:100%}.theory-layout{display:grid;grid-template-columns:minmax(210px,29%) minmax(0,1fr);gap:32px}.theory-topics{display:flex;flex-direction:column;align-items:stretch;justify-content:flex-start;gap:7px;max-height:75vh;overflow:auto;padding-right:10px}.theory-topics button{padding:12px;text-align:left;font-size:13px;line-height:1.5;white-space:normal;overflow-wrap:anywhere;flex-shrink:0}.theory-topics button.active{border-color:var(--accent);color:var(--accent)}#theoryArticle{min-width:0;overflow-wrap:anywhere}#theoryArticle h2{font-size:26px;line-height:1.35;margin-top:0}#theoryArticle h3{font-size:20px;margin-top:26px}.theory-lead{color:var(--muted);font-size:17px}.theory-example,.theory-formulas{padding:18px 20px;margin:25px 0;border:1px solid var(--line);border-radius:14px;background:var(--input)}.theory-example h3,.theory-formulas h3{margin-top:0!important}.theory-example li{margin-bottom:10px}.theory-formulas p{overflow-x:auto}
.result-sharing,.result-tournament{border-top:1px solid var(--line);padding-top:20px;margin-top:24px}.nickname-form{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:14px;align-items:end}.nickname-form button{min-height:48px}.leaderboard-toolbar{display:flex;align-items:center;justify-content:space-between;gap:18px;flex-wrap:wrap;margin:20px 0}.leaderboard-scroll{overflow:auto}.leaderboard-table{border-collapse:collapse;width:100%}.leaderboard-table th,.leaderboard-table td{padding:14px 16px;text-align:left;border-bottom:1px solid var(--line)}.leaderboard-table th:last-child,.leaderboard-table td:last-child{text-align:right}.leaderboard-table tr.mine{background:var(--input);color:var(--accent)}#resultEmailDialog{width:min(560px,calc(100vw - 24px))}#resultEmailStatus,.tournament-status{overflow-wrap:anywhere}
@media(max-width:760px){.theory-layout{grid-template-columns:1fr;gap:24px}.theory-topics{max-height:220px;padding-right:4px;border-bottom:1px solid var(--line);padding-bottom:16px}.theory-heading{align-items:flex-start;flex-direction:column;gap:5px}.theory-heading button{width:100%}.theory-filters{grid-template-columns:85px minmax(0,1fr);gap:12px}#theoryArticle h2{font-size:23px}.nickname-form{grid-template-columns:1fr}.nickname-form button{width:100%}.footer-actions{gap:8px 16px}.star-rating button{font-size:25px;min-width:38px;padding:5px}}
body[data-display=phone] .theory-layout,body[data-display=board] .theory-layout{grid-template-columns:1fr}body[data-display=phone] .theory-topics{max-height:220px}body[data-display=phone] .nickname-form{grid-template-columns:1fr}
@media(max-width:560px){.leaderboard-table th,.leaderboard-table td{padding:12px 8px}.leaderboard-table td:nth-child(2){max-width:150px;overflow-wrap:anywhere}}

.matching-options{border:0;padding:0;min-width:0}.matching-options legend{margin-bottom:16px;color:var(--muted)}.matching-row{display:grid;grid-template-columns:1fr 1fr;gap:16px;align-items:center;margin:12px 0}.matching-row select{width:100%;min-width:0;white-space:normal}@media(max-width:680px){.matching-row{grid-template-columns:1fr;gap:6px}}

.nom-filters{display:grid;grid-template-columns:2fr 2fr 1fr;gap:16px;margin:24px 0}.nom-filters label{display:block;margin-bottom:8px}.nom-filters select{width:100%}.nomenclature-view{padding:28px}.nom-formula{padding:20px;background:var(--bg);border:1px solid var(--line);border-radius:16px;margin:20px 0;overflow-wrap:anywhere}.nom-formula .structural{font-size:clamp(18px,3vw,28px);line-height:1.7}.nom-formula p{margin:6px 0}.nom-review-formula{overflow-wrap:anywhere}.header-actions{flex-wrap:wrap}.page-tabs{flex-wrap:wrap}@media(max-width:680px){.nom-filters{grid-template-columns:1fr}.nomenclature-view{padding:20px}.header .page-tabs button{padding:10px;font-size:12px}}

.workspace{grid-template-columns:minmax(0,1fr)}.workspace>section{grid-column:1!important}.section-view{padding:28px}.section-view>h1{font-size:clamp(28px,4vw,44px)}.header{flex-wrap:wrap}.header-actions{width:100%;justify-content:space-between}.page-tabs{gap:6px;flex-wrap:wrap;min-width:0}.page-tabs button{font-size:13px;padding:10px 12px}.coefficient-equation{display:flex;flex-wrap:wrap;gap:12px;align-items:center;margin:24px 0;font-size:24px}.coefficient-term{display:inline-flex;align-items:center;gap:6px}.coefficient-term input{width:60px!important;min-width:60px;text-align:center;padding:8px!important}.danger{border-color:var(--error);color:var(--error)}#editorQuestion{padding:20px;border:1px solid var(--line);border-radius:16px;overflow-wrap:anywhere;margin-bottom:20px}.editor-task-delete{margin-top:12px}@media(max-width:680px){.header-actions{gap:12px}.page-tabs{width:100%;display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}.header .page-tabs button{font-size:13px;width:100%}.section-view{padding:20px}.coefficient-equation{font-size:21px;gap:10px}.coefficient-term input{width:48px!important;min-width:48px}}

/* Section guides and classification. */
.section-guide-button{margin:0 0 16px}.section-guide-dialog{width:min(820px,calc(100vw - 24px));max-height:90vh;overflow-y:auto}.section-guide-dialog .dialog-header{align-items:flex-start}.section-guide-dialog h2{font-size:25px;line-height:1.3}.section-guide-dialog li{margin:10px 0}.section-guide-dialog p{line-height:1.7;overflow-wrap:anywhere}.section-guide-dialog #sectionGuideReturn{margin-top:20px}.class-filters{grid-template-columns:minmax(0,2fr) minmax(90px,1fr)}#classPrompt{line-height:1.6}#classificationView .matching-row>span{font-size:22px}#classificationView .answer-options{border:0;padding:0;min-width:0}#extraSectionGuide{margin-left:auto}@media(max-width:680px){.class-filters{grid-template-columns:1fr}.section-guide-dialog{padding:20px}.section-guide-dialog h2{font-size:22px}#extraSectionGuide{padding:8px;margin:0}}

#classResult .review-item p{white-space:pre-line}

.section-guide-dialog p{white-space:pre-line}.guide-exceptions{border-left:3px solid var(--accent);padding-left:18px;margin:24px 0}

.question-community{position:relative;padding-bottom:36px}.rating-average{position:absolute;right:0;bottom:0;color:var(--accent);font-weight:600;font-size:14px;text-align:right}#resetTopics{margin-right:10px}

.calc-other-heading{grid-column:1/-1;margin:14px 0 4px}
/* Homeworks and teacher catalog */
.teacher-workspace{max-width:1150px;width:94vw}.teacher-catalog-filters{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.teacher-catalog-filters label{min-width:0}.teacher-catalog-filters select{max-width:100%}.teacher-catalog-row{display:flex;align-items:flex-start;gap:14px;padding:15px 0;border-bottom:1px solid var(--line)}.teacher-catalog-row>button{text-align:left;white-space:normal}.teacher-catalog-row span,.teacher-catalog-row small{display:block}.teacher-print-options{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin:12px 0}.teacher-print-options label{display:flex;gap:8px}.teacher-task-preview{text-align:left;white-space:normal}.teacher-list li{overflow-wrap:anywhere}#teacherCreated a{overflow-wrap:anywhere}#teacherTaskBody img{max-width:100%}#teacherDialog input[type=checkbox]{width:20px;min-height:20px}.homework-shell{max-width:1100px;margin:20px auto;padding:20px}.homework-shell>.brand{display:block;margin:0 0 20px;font-size:36px}.homework-task{padding:24px 0;border-bottom:1px solid var(--line)}.homework-task textarea{width:100%}.homework-task-image{max-width:100%;height:auto}.homework-task h2{font-size:21px}.hw-save-note{margin-left:12px;color:var(--accent)}.homework-shell progress{width:100%}.homework-shell #hwFinish{margin-top:25px}.task-image{max-width:100%}#teacherTaskDialog{max-width:900px;width:92vw}#teacherDialog hr{margin:24px 0}
@media(max-width:680px){.teacher-catalog-filters,.teacher-print-options{grid-template-columns:1fr}.homework-shell{padding:12px;margin:0}.homework-task{padding:20px 0}.homework-shell .panel{padding:18px}.teacher-workspace{padding:16px}.teacher-catalog-row{gap:8px}}
.module-view{margin-top:28px;min-width:0}.module-view[hidden]{display:none}.module-frame-host{width:100%;min-width:0}.activity-frame{display:block;width:100%;max-width:100%;border:1px solid var(--line);border-radius:18px;background:var(--card)}.module-status{padding:12px 0}@media(max-width:680px){.module-view{margin-top:20px}.activity-frame{border-radius:12px}.page-tabs button{min-height:46px}.page-tabs #tutorTab{line-height:1.25}}