:root{--bg:#ffffff;--surface:#ffffff;--surface-soft:#f1f6fa;--text:#243443;--muted:#667a8b;--line:#dbe5ec;--accent:#0077b5;--accent-strong:#005e93;--accent-soft:#e8f4fc;--good:#05689b;--answer-bg:#eaf5fc;--signal:#0088cc;--on-blue:#ffffff;--ink:#006ba7;--ink-soft:#005789;--shadow:0 4px 16px #123b5c0a;--warning-bg:#fff2f3;--warning-text:#9b464c;color-scheme:light;font-family:Roboto,Arial,"Helvetica Neue",system-ui,sans-serif;font-synthesis:none}
:root[data-theme=dark]{--bg:#101d2b;--surface:#17283a;--surface-soft:#21384b;--text:#eef6fb;--muted:#acc1d2;--line:#385267;--accent:#5dbbfa;--accent-strong:#a8dfff;--accent-soft:#193d57;--good:#9edfff;--answer-bg:#16415a;--signal:#57b9f5;--on-blue:#ffffff;--ink:#006ba7;--ink-soft:#005789;--shadow:0 4px 16px #0002;--warning-bg:#452b3a;--warning-text:#efbdc9;color-scheme:dark}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--text);line-height:1.55;min-width:300px}button,input,textarea,select{font:inherit}button,a,input,textarea,select{-webkit-tap-highlight-color:transparent}button,a{touch-action:manipulation}button{border:0;background:none;color:inherit;cursor:pointer}button,a{transition:background .16s,color .16s,border-color .16s,transform .16s}button:disabled{cursor:default;opacity:.55}a{color:inherit}button:focus-visible,a:focus-visible,select:focus-visible{outline:3px solid var(--signal);outline-offset:4px}svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round;flex:none}.sprite{position:absolute;width:0;height:0;overflow:hidden}.wrap{max-width:1200px;margin:0 auto;padding:0 32px}.technical-line{background:var(--ink);color:#e4f3fc;font:9px/1.2 ui-monospace,SFMono-Regular,Consolas,monospace;letter-spacing:1.5px}.technical-line>.wrap{height:30px;display:flex;align-items:center;justify-content:space-between;gap:15px}.technical-line span{display:flex;align-items:center;gap:8px}.technical-line i,.tech-card-top i{width:5px;height:5px;background:var(--signal);display:inline-block}.site-header{height:88px;display:flex;align-items:center;justify-content:space-between;gap:20px}.brand{text-transform:uppercase;display:flex;align-items:center;gap:11px;text-decoration:none;font-size:12px;line-height:1.25;letter-spacing:.9px;font-weight:500}.brand strong{font-weight:800}.brand-mark{width:43px;height:43px;background:var(--ink);color:#ffffff;font-size:31px;line-height:45px;font-weight:800;padding-left:10px;position:relative;border-radius:3px}.brand-mark>span{color:var(--signal);font-size:26px;position:absolute;right:3px;bottom:-1px}.site-header nav{display:flex;align-items:center;gap:19px}.text-button{display:inline-flex;align-items:center;justify-content:center;gap:7px;font-size:12px;font-weight:700;padding:9px 4px;text-decoration:none;color:var(--muted)}.text-button:hover{color:var(--accent)}#browse-button>span{font:10px ui-monospace,Consolas,monospace;background:var(--on-blue);color:var(--ink);padding:3px 5px}.icon-button{width:38px;height:38px;display:inline-flex;align-items:center;justify-content:center;flex:none;color:var(--muted);border-radius:3px}.icon-button:hover{background:var(--surface-soft);color:var(--text)}.theme-button{border:1px solid var(--line)}.theme-button svg{width:18px;height:18px}.mode-switch{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));border:1px solid var(--text);background:var(--surface);margin:0 0 27px}.mode-tab{min-height:72px;display:flex;align-items:center;gap:15px;padding:13px 20px;text-decoration:none;position:relative}.mode-tab+.mode-tab{border-left:1px solid var(--text)}.mode-tab:hover{background:var(--surface-soft)}.mode-tab.is-current{background:var(--ink);color:#ffffff}.mode-number{font:11px ui-monospace,Consolas,monospace;opacity:.55;align-self:flex-start;padding-top:5px}.mode-tab strong{font-size:16px;display:block;font-weight:750;letter-spacing:-.3px}.mode-tab small{font-size:10px;display:block;opacity:.65;margin-top:2px}.mode-tab>svg{width:21px;height:21px;margin-left:auto}.mode-autotest{background:var(--on-blue);color:var(--ink)}.mode-autotest:hover{background:#0077b5}.mode-autotest .mode-number{opacity:.65}.hero{display:grid;grid-template-columns:1.3fr 1fr;gap:50px;align-items:center;margin:26px 0 32px;min-height:218px}.eyebrow{font:9px ui-monospace,SFMono-Regular,Consolas,monospace;font-weight:700;letter-spacing:1.6px;color:var(--accent);display:flex;align-items:center;gap:8px}.live-dot{width:6px;height:6px;background:var(--signal);display:inline-block}.hero h1{font-size:clamp(48px,5.6vw,74px);line-height:.99;font-weight:850;letter-spacing:-4px;margin:17px 0 15px}.hero h1 span{color:var(--text)}.hero-copy{font-size:13px;color:var(--muted);line-height:1.65;margin:0}.technical-card{justify-self:end;width:100%;max-width:370px;background:var(--ink);color:#c5e6fa;padding:15px 18px 17px;border:1px solid #88bde0;position:relative;overflow:hidden}.technical-card::before{content:"";position:absolute;inset:0;background-image:linear-gradient(#ffffff05 1px,transparent 1px),linear-gradient(90deg,#ffffff05 1px,transparent 1px);background-size:19px 19px;pointer-events:none}.tech-card-top{font:8px ui-monospace,Consolas,monospace;letter-spacing:1.2px;display:flex;justify-content:space-between;position:relative}.tech-card-top span:first-child{display:flex;align-items:center;gap:6px}.pipe-drawing{width:100%;height:104px;color:#a6d7f4;display:block;margin:8px 0}.tech-card-bottom{display:flex;gap:32px;position:relative}.tech-card-bottom>div{display:flex;align-items:baseline;gap:7px}.tech-card-bottom strong{color:#ffffff;font-size:29px;font-weight:600;line-height:1}.tech-card-bottom span{font:8px ui-monospace,Consolas,monospace;color:#b6ddf3;max-width:54px}.tech-card-bottom .tech-check{display:grid;place-items:center;width:28px;height:28px;border:1px solid #ffffff77;color:var(--on-blue);font-size:17px;margin-left:auto;max-width:none}.search-section{max-width:none;margin:0 auto}.search-card{background:var(--surface);border:2px solid var(--text);padding:0 21px 12px;position:relative;box-shadow:7px 7px 0 var(--line)}.search-card:focus-within{border-color:var(--accent)}.search-card-title{display:flex;justify-content:space-between;font:8px ui-monospace,Consolas,monospace;letter-spacing:1.35px;color:var(--muted);border-bottom:1px solid var(--line);margin:0 -21px 5px;padding:9px 21px}.search-card-title span:first-child{color:var(--accent);font-weight:700}.input-row{display:flex;align-items:center;gap:15px;min-height:65px}.search-icon{width:24px;height:24px;color:var(--accent)}#query{width:100%;min-width:0;resize:none;border:0;outline:0;box-shadow:none;background:transparent;color:var(--text);padding:16px 0;line-height:1.45;font-size:20px;min-height:60px;max-height:195px;overflow-y:auto}#query::placeholder{color:#858c8f;opacity:1}.clear-button{width:30px;height:30px}.clear-button svg{width:17px;height:17px}.voice-button{display:flex;gap:8px;align-items:center;justify-content:center;background:var(--signal);color:var(--ink);height:44px;min-width:44px;padding:0 15px;font-size:12px;font-weight:800;flex:none;border-radius:2px}.voice-button:hover{background:#ee642e}.voice-button[aria-pressed=true]{background:#005789;color:#fff;animation:breathe 1.4s ease-in-out infinite}.voice-button svg{width:19px;height:19px}.search-divider{height:1px;background:var(--line);margin:4px 0 5px}.search-actions{display:flex;align-items:center;justify-content:space-between;gap:12px}.file-actions{display:flex;align-items:center;gap:8px}.upload-button,.camera-button{display:flex;align-items:center;gap:8px;padding:9px 4px;font-size:11px;font-weight:650;color:var(--muted);white-space:nowrap}.upload-button:hover,.camera-button:hover{color:var(--accent)}.upload-button svg,.camera-button svg{width:16px;height:16px}.camera-button{border-left:1px solid var(--line);padding-left:14px}.drop-hint{font-size:10px;color:var(--muted)}kbd{font:9px ui-monospace,monospace;border:1px solid var(--line);padding:2px 4px;margin-left:4px}.drop-overlay{display:none;position:absolute;inset:0;border:2px dashed var(--accent);background:var(--surface);z-index:2;align-items:center;justify-content:center;flex-direction:column;gap:9px;pointer-events:none}.drop-overlay svg{width:30px;height:30px;color:var(--accent)}.drop-overlay strong{font-size:19px}.drop-overlay span{font-size:12px;color:var(--muted)}.drag-active .drop-overlay{display:flex}.search-caption{display:flex;gap:24px;flex-wrap:wrap;padding:14px 0 0;font-size:9px;color:var(--muted)}.search-caption>span{display:flex;align-items:center;gap:6px}.search-caption svg{width:13px;height:13px}.input-status{display:flex;align-items:center;gap:8px;padding-top:10px;color:var(--accent);font-size:12px}.input-status .text-button{margin-left:auto;font-size:11px}.status-dot{width:6px;height:6px;background:currentColor;animation:breathe 1s infinite}.ocr-progress{height:3px;background:var(--line);margin-top:8px;overflow:hidden}.ocr-progress>div{height:100%;width:0;background:var(--signal);transition:width .15s}.input-error{display:flex;align-items:center;gap:8px;background:var(--warning-bg);color:var(--warning-text);font-size:12px;line-height:1.55;padding:10px 12px;margin-top:10px;border-left:3px solid var(--warning-text)}.input-error>svg{width:17px;height:17px}.input-error .icon-button{margin-left:auto;width:25px;height:25px;color:inherit}.image-panel{display:flex;align-items:center;gap:16px;padding:14px;border:1px solid var(--line);margin-top:16px;background:var(--surface)}.image-panel>img{width:86px;max-height:100px;object-fit:contain;background:var(--surface-soft)}.image-info{min-width:0}.image-info>strong{display:block;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;font-size:12px}.image-info>span{display:block;color:var(--muted);font-size:11px;margin-top:4px}.image-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:5px}.image-actions .text-button{font-size:10px;padding:4px}.image-actions svg{width:13px;height:13px}.start-section{margin:21px 0 0}.suggestion-row{display:flex;align-items:center;gap:8px;flex-wrap:wrap;font-size:10px;color:var(--muted)}.suggestion-row>span{margin-right:5px}.suggestion-row button{display:flex;align-items:center;gap:9px;border:1px solid var(--line);padding:7px 10px;background:transparent;font-size:10px;font-weight:600}.suggestion-row button:hover{background:var(--text);color:var(--bg);border-color:var(--text)}.suggestion-row svg{width:12px;height:12px}.action-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin-top:31px}.action-panel{padding:21px 24px 18px;text-decoration:none;display:flex;flex-direction:column;border:1px solid var(--text);position:relative;min-width:0}.preparation-panel{background:var(--ink);color:#f6f2e9}.autotest-panel{background:var(--on-blue);color:var(--ink)}.action-panel:hover{transform:translateY(-3px);box-shadow:4px 4px 0 var(--line)}.action-panel-top{display:flex;align-items:center;justify-content:space-between;font:9px ui-monospace,Consolas,monospace;letter-spacing:1.4px;opacity:.75}.action-panel-top svg{width:17px;height:17px}.action-panel h3{font-size:25px;line-height:1.15;letter-spacing:-.9px;margin:20px 0 12px;font-weight:700}.action-panel p{font-size:12px;line-height:1.7;max-width:370px;margin:0 0 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5px}.results-toolbar h2{font-size:29px;line-height:1.2;letter-spacing:-1px;margin:0}.topic-filter{position:relative;max-width:330px;flex-shrink:0}.topic-filter select{appearance:none;-webkit-appearance:none;padding:10px 32px 10px 11px;border:1px solid var(--line);color:var(--muted);background:var(--surface);font-size:11px;max-width:100%;text-overflow:ellipsis;border-radius:0}.topic-filter svg{position:absolute;right:10px;top:50%;transform:translateY(-50%);width:13px;height:13px;pointer-events:none;color:var(--muted)}.match-hint{font-size:12px;color:var(--muted);margin:0 0 15px}.match-hint:empty{display:none}.results-list{display:grid;gap:15px;counter-reset:answer}.answer-card{background:var(--surface);border:1px solid var(--line);border-left:5px solid var(--line);padding:22px 25px;position:relative;counter-increment:answer}.answer-card::before{content:counter(answer,decimal-leading-zero);position:absolute;top:22px;right:23px;font:10px ui-monospace,Consolas,monospace;color:var(--muted);opacity:.6}.answer-card.top-result{border-color:var(--text);border-left-color:var(--signal)}.card-meta{display:flex;align-items:center;gap:10px;padding-right:35px;margin-bottom:12px}.topic-label{font:9px/1.5 ui-monospace,Consolas,monospace;color:var(--muted)}.match-badge{font:8px/1.4 ui-monospace,Consolas,monospace;color:var(--accent);border:1px solid var(--line);padding:3px 5px;white-space:nowrap;margin-left:auto}.answer-card h3{font-size:19px;line-height:1.5;font-weight:700;letter-spacing:-.4px;margin:0 0 17px;max-width:900px}.answer-card mark{background:var(--on-blue);color:var(--ink);padding:0 2px}.correct-answers{list-style:none;margin:0;padding:0;display:grid;gap:7px}.correct-answers li{display:flex;align-items:flex-start;gap:11px;padding:12px 14px;border-left:2px solid var(--good);background:var(--answer-bg);color:var(--good);font-size:14px;font-weight:600;line-height:1.65}.correct-answers svg{width:18px;height:18px;stroke-width:2;margin-top:2px}.card-bottom{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-top:15px}.verified-label{display:flex;align-items:center;gap:5px;font:9px ui-monospace,Consolas,monospace;color:var(--muted)}.verified-label svg{width:12px;height:12px}.copy-answer{display:flex;align-items:center;gap:6px;font-size:11px;font-weight:600;padding:5px 7px;color:var(--muted)}.copy-answer svg{width:13px;height:13px}.copy-answer:hover{background:var(--surface-soft);color:var(--accent)}.variant-details{margin-top:12px;border-top:1px solid var(--line);padding-top:12px}.variant-details summary,.caveat-details summary{cursor:pointer;list-style:none;display:flex;align-items:center;gap:6px;font-size:11px;color:var(--muted)}.variant-details summary::-webkit-details-marker,.caveat-details summary::-webkit-details-marker{display:none}.variant-details summary svg,.caveat-details summary svg{width:13px;height:13px;transition:transform .2s}details[open]>summary svg{transform:rotate(180deg)}.variant-details ul{list-style:none;padding:7px 0 0;margin:0;display:grid;gap:6px}.variant-details li{display:flex;gap:9px;font-size:12px;line-height:1.6;color:var(--muted);padding:4px 0}.variant-details li.correct{color:var(--good);font-weight:650}.variant-dot{width:13px;height:13px;border:1px solid var(--line);margin-top:3px;flex:none}.variant-details li.correct .variant-dot{background:var(--good);border-color:var(--good);position:relative}.variant-details li.correct .variant-dot::after{content:"✓";position:absolute;top:-4px;left:1px;color:var(--surface);font-size:10px}.caveat-details{margin-top:13px;border-left:3px solid var(--warning-text);padding:9px 12px;background:var(--warning-bg);color:var(--warning-text)}.caveat-details summary{color:inherit}.caveat-details p{font-size:12px;line-height:1.7;margin:9px 0 5px}.caveat-details a{font-size:11px;text-underline-offset:3px}.empty-state{text-align:center;padding:40px 25px;background:var(--surface);border:1px solid var(--line)}.empty-icon{display:inline-flex;background:var(--surface-soft);padding:14px;color:var(--muted)}.empty-icon svg{width:28px;height:28px}.empty-state h3{font-size:21px;letter-spacing:-.5px;margin:17px 0 8px}.empty-state p{font-size:13px;color:var(--muted);max-width:400px;margin:0 auto 20px}.secondary-button{display:inline-flex;align-items:center;justify-content:center;gap:8px;border:1px solid var(--text);padding:11px 15px;background:var(--surface);font-size:12px;font-weight:700;color:var(--text);border-radius:2px}.secondary-button:hover{background:var(--surface-soft)}.secondary-button svg{width:15px;height:15px}.show-more{display:flex;margin:20px auto 0;min-width:170px}.study-note{display:flex;align-items:flex-start;gap:10px;margin-top:30px;padding:17px 0;border-top:1px solid var(--line);color:var(--muted)}.study-note svg{width:15px;height:15px;margin-top:3px;opacity:.7}.study-note p{font-size:10px;line-height:1.8;margin:0;max-width:840px}.study-note strong{font-weight:700}.site-footer{display:flex;align-items:center;justify-content:space-between;gap:15px;padding-top:20px;padding-bottom:27px;color:var(--muted);font:8px ui-monospace,Consolas,monospace;letter-spacing:.8px}.site-footer a{display:flex;align-items:center;gap:7px;text-decoration:none;font:10px Arial,sans-serif;letter-spacing:0}.site-footer a:hover{color:var(--accent)}.site-footer svg{width:12px;height:12px}.sr-only{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}[hidden]{display:none!important}dialog{max-width:480px;width:calc(100% - 32px);border:1px solid var(--text);background:var(--surface);color:var(--text);border-radius:2px;padding:26px;box-shadow:12px 12px 0 #0003}dialog::backdrop{background:#10192299;backdrop-filter:blur(3px)}.dialog-header{display:flex;align-items:center;justify-content:space-between}.dialog-header .eyebrow{font-size:9px}dialog h2{font-size:27px;letter-spacing:-.9px;margin:10px 0 24px}.help-list{list-style:none;margin:0;padding:0;counter-reset:help}.help-list li{position:relative;counter-increment:help;padding:0 0 22px 36px}.help-list li::before{content:counter(help,decimal-leading-zero);position:absolute;left:0;top:1px;font:11px ui-monospace,Consolas,monospace;color:var(--accent);border-bottom:2px solid var(--signal);padding:3px 0}.help-list strong{display:block;font-size:14px;margin-bottom:4px}.help-list span{display:block;color:var(--muted);font-size:12px;line-height:1.7}.help-tip{padding:12px;border-left:3px solid var(--signal);background:var(--surface-soft);color:var(--muted);font-size:11px;line-height:1.7}.primary-button{background:var(--ink);color:#ffffff;border:1px solid var(--ink);padding:13px 18px;font-size:13px;font-weight:750;display:flex;align-items:center;justify-content:center;gap:10px;width:100%;margin-top:18px;border-radius:2px}.primary-button:hover{background:var(--signal);border-color:var(--signal);color:var(--ink)}.primary-button svg{width:17px;height:17px}.toast{position:fixed;bottom:25px;left:50%;transform:translateX(-50%);padding:13px 18px;color:#ffffff;background:var(--ink);box-shadow:5px 5px 0 #0002;font-size:12px;border-left:4px solid var(--signal);max-width:calc(100% - 32px);z-index:10;text-align:center}.noscript{padding:20px;text-align:center;background:var(--warning-bg)}.loading-state{padding:30px;text-align:center;color:var(--muted);font-size:13px}body.searching .hero{display:none}body.searching .mode-switch{margin-bottom:24px}body.searching .search-section{margin-top:5px}.auto-link{text-decoration:none}
@keyframes breathe{0%,100%{opacity:1}50%{opacity:.5}}
@media(max-width:900px){.hero{gap:30px}.mode-tab{padding:13px 15px;gap:10px}.mode-tab strong{font-size:15px}.technical-card{max-width:330px}.action-panel h3{font-size:23px}}
@media(max-width:700px){.wrap{padding-left:20px;padding-right:20px}.technical-line>.wrap{height:26px;font-size:7px;letter-spacing:1px}.technical-line span:last-child{display:none}.site-header{height:74px}.site-header nav{gap:11px}.brand{font-size:10px;gap:8px;letter-spacing:.5px}.brand-mark{width:35px;height:35px;font-size:26px;line-height:37px;padding-left:8px}.brand-mark>span{font-size:22px;right:2px}.text-button{font-size:11px}.theme-button{width:33px;height:33px}.theme-button svg{width:16px;height:16px}#help-button{display:none}.mode-switch{margin-bottom:22px}.mode-tab{min-height:76px;padding:12px 10px;gap:7px;align-items:flex-start}.mode-number{font-size:9px;padding-top:3px}.mode-tab strong{font-size:12px;letter-spacing:-.2px}.mode-tab small{font-size:8px;line-height:1.35;margin-top:4px;max-width:100px}.mode-tab>svg{display:none}.hero{grid-template-columns:1fr;margin:22px 0 24px;min-height:0}.hero h1{font-size:56px;letter-spacing:-3.3px;margin:15px 0 11px}.hero h1 br{display:none}.hero h1 span::before{content:" "}.hero-copy{font-size:12px;max-width:360px}.hero-copy br{display:none}.technical-card{display:none}.eyebrow{font-size:8px;letter-spacing:1.1px}.search-card{padding:0 13px 9px;box-shadow:4px 4px 0 var(--line)}.search-card-title{margin:0 -13px 4px;padding:8px 13px;font-size:7px;letter-spacing:1px}.input-row{gap:9px;min-height:58px}.search-icon{width:21px;height:21px}#query{font-size:17px;min-height:56px;padding:14px 0}.voice-button{padding:0;min-width:42px;width:42px;height:42px}.voice-label{display:none}.drop-hint{display:none}.search-actions{justify-content:center}.file-actions{justify-content:center;gap:10px;width:100%}.upload-button,.camera-button{font-size:10px;padding-top:10px;padding-bottom:7px}.camera-button{padding-left:13px}.search-caption{font-size:8px;gap:5px 15px;line-height:1.6}.search-caption svg{width:11px;height:11px}.suggestion-row{font-size:9px;gap:6px}.suggestion-row button{font-size:9px;padding:6px 8px}.suggestion-row>span{display:none}.action-grid{gap:13px;margin-top:23px}.action-panel{padding:15px 14px;min-height:231px}.action-panel h3{font-size:20px;letter-spacing:-.6px;margin:20px 0 10px}.action-panel p{font-size:10px;line-height:1.65;margin-bottom:14px}.action-panel-top{font-size:7px;letter-spacing:.8px}.action-panel-top svg{width:14px;height:14px}.action-panel>strong{font-size:9px;padding-top:10px}.all-questions{font-size:10px;padding:14px;margin-top:13px}.results-section{margin-top:24px}.results-toolbar{align-items:center;padding-bottom:12px}.results-toolbar h2{font-size:24px;letter-spacing:-.7px}.section-eyebrow{font-size:7px;letter-spacing:1px}.topic-filter{max-width:44%}.topic-filter select{font-size:10px;padding:9px 25px 9px 9px}.topic-filter svg{right:8px}.answer-card{padding:18px 16px;border-left-width:4px}.answer-card::before{right:14px;top:20px;font-size:9px}.card-meta{align-items:flex-start;gap:6px;padding-right:25px;margin-bottom:11px;flex-wrap:wrap}.topic-label{font-size:8px;max-width:100%}.match-badge{font-size:7px;margin-left:0}.answer-card h3{font-size:17px;line-height:1.55;letter-spacing:-.2px}.correct-answers li{font-size:13px;padding:10px 11px;gap:8px}.correct-answers svg{width:16px;height:16px}.card-bottom{align-items:flex-start;gap:6px}.verified-label{font-size:8px;line-height:1.5}.verified-label svg{width:11px;height:11px}.copy-answer{font-size:10px;white-space:nowrap;padding:2px}.copy-answer svg{width:12px;height:12px}.variant-details summary,.caveat-details summary{font-size:10px}.variant-details li{font-size:11px}.image-panel{gap:12px;padding:11px}.image-panel>img{width:64px;max-height:80px}.image-info>strong{font-size:11px}.image-info>span{font-size:10px}.image-info>span br{display:none}.image-actions{gap:5px}.image-actions .text-button{font-size:9px}.study-note{margin-top:24px;padding-top:15px}.study-note p{font-size:9px}.site-footer{flex-direction:column;align-items:flex-start;gap:10px;padding-top:18px;font-size:7px;line-height:1.7;padding-bottom:max(25px,env(safe-area-inset-bottom))}.site-footer a{font-size:9px}.input-error{font-size:11px;padding:9px}.input-status{font-size:11px}.search-card-title span:last-child{display:none}.match-hint{font-size:11px}.empty-state{padding:30px 18px}.empty-state h3{font-size:19px}.empty-state p{font-size:12px}}
@media(max-width:400px){.wrap{padding-left:16px;padding-right:16px}.hero h1{font-size:46px;letter-spacing:-2.7px}.mode-tab{padding:10px 7px;gap:5px;min-height:81px}.mode-number{font-size:8px}.mode-tab strong{font-size:11px}.mode-tab small{font-size:8px}.site-header nav{gap:8px}.brand{font-size:9px}#browse-button>span{display:none}.action-grid{grid-template-columns:1fr}.action-panel{min-height:0;padding:17px 18px}.action-panel h3{font-size:24px;margin:14px 0 10px}.action-panel p{font-size:11px;max-width:300px}.action-panel h3 br{display:none}.action-panel>strong{font-size:10px}.action-panel-top{font-size:8px}.search-caption{flex-direction:column;gap:4px}.answer-card h3{font-size:16px}.correct-answers li{font-size:12px}.card-bottom{flex-wrap:wrap}.topic-filter{max-width:46%}.results-toolbar h2{font-size:22px}.hero-copy{font-size:11px}.all-questions{font-size:9px;letter-spacing:.3px}.theme-button{width:31px;height:31px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}html{scroll-behavior:auto!important}}

@media(max-width:400px){.mode-number{display:none}.mode-tab{padding:11px 9px}.mode-tab strong{font-size:12px}.mode-tab small{font-size:9px;line-height:1.4}}

/* Blue and white gas-industry styling, informed by ugaz.ru/ks/. */
.technical-line{background:var(--ink);font-family:Roboto,Arial,sans-serif;letter-spacing:1.2px}
.technical-line i,.tech-card-top i{background:#9dddfd}
.site-header{height:96px}
.brand{color:var(--accent);font-size:12px;letter-spacing:.7px}
.brand-mark{background:var(--ink);border-radius:2px}
.brand-mark>span{color:#bce9ff}
.brand strong{font-weight:700}
.mode-switch{border-color:var(--line);margin-top:0;box-shadow:0 2px 10px #006ba706}
.mode-tab+.mode-tab{border-color:var(--line)}
.mode-tab{min-height:76px}
.mode-tab.is-current{background:var(--ink);color:#fff}
.mode-tab strong{font-weight:600}
.mode-tab small{opacity:1;color:var(--muted)}
.mode-tab.is-current small,.mode-autotest small{color:#d6efff}
.mode-number{font-family:Roboto,Arial,sans-serif;opacity:.65}
.mode-autotest{background:var(--signal);color:#fff}
.mode-autotest:hover{background:#0077b5}
.mode-autotest:hover small{color:#fff}
.hero{margin:32px 0 34px;min-height:214px;gap:45px}
.hero h1{font-size:clamp(48px,5.1vw,68px);font-weight:600;letter-spacing:-2.6px;line-height:1.02}
.hero h1 span{color:var(--accent)}
.eyebrow,.section-eyebrow{font-family:Roboto,Arial,sans-serif;letter-spacing:1.35px;font-weight:500}
.hero-copy{font-size:13px;line-height:1.75}
.technical-card{background:var(--accent-soft);border:1px solid var(--line);color:var(--accent);padding:19px 21px;max-width:385px}
.technical-card::before{background-image:linear-gradient(#0088cc08 1px,transparent 1px),linear-gradient(90deg,#0088cc08 1px,transparent 1px);background-size:21px 21px}
.tech-card-top{color:var(--accent);font-family:Roboto,Arial,sans-serif;font-weight:500;letter-spacing:1px}
.tech-card-top i{background:var(--signal)}
.pipe-drawing{color:var(--accent);height:106px}
.tech-card-bottom strong{color:var(--accent);font-weight:500}
.tech-card-bottom span{color:var(--muted);font-family:Roboto,Arial,sans-serif;font-size:9px}
.tech-card-bottom .tech-check{color:var(--accent);border-color:var(--accent);font-size:17px}
.search-card{border:1px solid var(--line);border-top:3px solid var(--signal);box-shadow:0 5px 20px #00527a0a}
.search-card-title{font-family:Roboto,Arial,sans-serif;letter-spacing:1.2px;background:var(--surface-soft)}
.voice-button{color:#fff;background:var(--signal)}
.voice-button:hover{color:#fff;background:#0077b5}
.primary-button{background:var(--ink);color:#fff}
.primary-button:hover{background:#005789}
.action-grid{gap:20px}
.action-panel{border:1px solid var(--line);padding:25px 25px 19px}
.action-panel h3{font-weight:500;letter-spacing:-.7px;font-size:26px}
.action-panel-top{font-family:Roboto,Arial,sans-serif;letter-spacing:1.3px}
.preparation-panel{background:var(--surface-soft);color:var(--text);border-top:3px solid var(--ink)}
.preparation-panel p{color:var(--muted)}
.preparation-panel>strong{border-color:var(--line);color:var(--accent)}
.preparation-panel:hover{background:var(--accent-soft)}
.autotest-panel{background:var(--ink);color:#fff;border-color:var(--ink);border-top:3px solid var(--signal)}
.autotest-panel p{color:#d8edf9}
.autotest-panel>strong{border-color:#6aadd377;color:#fff}
.autotest-panel:hover{background:#005f99}
.all-questions{font-size:12px;font-weight:500;color:var(--accent);background:var(--surface);border-color:var(--line)}
.all-questions:hover{background:var(--accent-soft)}
.answer-card{border-color:var(--line);border-left-color:var(--line);box-shadow:0 3px 12px #00527a05}
.answer-card.top-result{border-left-color:var(--signal)}
.answer-card h3{font-weight:500}
.answer-card::before,.topic-label,.match-badge{font-family:Roboto,Arial,sans-serif}
.match-badge{background:var(--accent-soft);color:var(--accent)}
.correct-answers li{border-radius:2px}
.site-footer{font-family:Roboto,Arial,sans-serif;letter-spacing:.7px}
@media(max-width:900px){.action-panel h3{font-size:23px}}
@media(max-width:700px){.site-header{height:77px}.hero{margin:24px 0;min-height:0}.hero h1{font-size:54px;letter-spacing:-2px}.technical-line>.wrap{height:25px;font-size:7px}.mode-tab{min-height:79px}.mode-tab strong{font-size:12px}.mode-tab small{font-size:8px}.search-card{box-shadow:0 4px 16px #00527a0b}.action-panel{padding:17px 15px}.action-panel h3{font-size:21px}.action-panel p{font-size:11px}.all-questions{font-size:10px}.hero-copy{font-size:12px}.site-footer{font-size:8px}.eyebrow{font-size:8px}}
@media(max-width:400px){.hero h1{font-size:46px;letter-spacing:-1.6px}.mode-tab{padding:11px 9px;min-height:83px}.mode-tab strong{font-size:12px}.mode-tab small{font-size:9px}.action-panel{padding:20px}.action-panel h3{font-size:25px;line-height:1.15}.hero-copy{font-size:11px}.all-questions{font-size:10px}}

.mode-autotest,.voice-button{background:#0077b5}.action-panel p{opacity:1}.hero-copy>span{display:block}@media(max-width:700px){.hero-copy>span{display:inline}.hero-copy>span+span::before{content:" "}}