:root{--text:#172033;--muted:#667085;--line:#e3e7ef;--blue:#2368ff;--green:#11875d;--bg:#f5f7fb;--surface:#fff}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--text);font:16px/1.6 Inter,-apple-system,BlinkMacSystemFont,"Segoe UI",Arial,sans-serif;letter-spacing:0}a{color:#1b55d3;text-underline-offset:3px}button,input,select{font:inherit}button,a,input,select,summary{touch-action:manipulation}button{cursor:pointer}[hidden]{display:none!important}.wrap{width:min(1160px,calc(100% - 40px));margin:auto}.topbar{background:#fff;border-bottom:1px solid var(--line)}.topbar-inner{min-height:68px;display:flex;align-items:center;justify-content:space-between;gap:24px}.brand{font-size:24px;font-weight:800;text-decoration:none;color:var(--text)}.brand b{color:var(--blue)}.topnav{display:flex;gap:22px;align-items:center}.topnav a{font-size:14px;text-decoration:none;font-weight:650;white-space:nowrap}.breadcrumbs{font-size:13px;color:var(--muted);padding-top:25px}.page-head{padding:25px 0 30px}.eyebrow{font-size:12px;text-transform:uppercase;font-weight:800;color:var(--blue)}h1,h2,h3{line-height:1.25;letter-spacing:0}h1{font-size:34px;margin:10px 0 14px;max-width:950px}h2{font-size:23px;margin:28px 0 14px}h3{font-size:18px;margin:0 0 10px}.page-head p{font-size:17px;max-width:850px;color:#526077;margin:0}.section{padding:0 0 38px}.catalog-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.catalog-item{border:1px solid var(--line);border-radius:8px;background:#fff;padding:22px;display:flex;flex-direction:column;min-width:0}.catalog-item p{color:var(--muted);font-size:14px;margin:0 0 18px}.catalog-item>a:last-child{margin-top:auto;align-self:flex-start;font-weight:650}.catalog-item .eyebrow{margin-bottom:9px}.catalog-row{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:20px}.catalog-row h2{margin:0}.button{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:9px 18px;background:#fff;border:1px solid #cbd4e2;border-radius:6px;color:var(--text);font-size:15px;font-weight:700;text-decoration:none;white-space:normal;text-align:center}.button:hover{border-color:var(--blue)}.button.primary{background:var(--blue);color:#fff;border-color:var(--blue)}.button.primary:hover{background:#174fc9}.button:disabled{opacity:.6;cursor:default}.button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid #7aa2ff;outline-offset:3px}.search-field{display:block;width:min(500px,100%);margin-bottom:24px}.search-field span{display:block;font-size:13px;color:var(--muted);margin-bottom:5px}.search-field input,.field input:not([type=range]),.field select{width:100%;min-height:46px;padding:10px 12px;background:#fff;border:1px solid #cbd4e2;border-radius:6px;color:var(--text)}.search-results{margin-bottom:30px;border-top:1px solid var(--line)}.search-hit{display:block;padding:16px 0;border-bottom:1px solid var(--line);text-decoration:none}.search-hit p{font-size:14px;margin:5px 0 0;color:var(--muted)}.article-layout{display:grid;grid-template-columns:minmax(0,780px) minmax(220px,1fr);gap:48px;padding-bottom:50px}.prose{min-width:0}.prose>h2:first-child{margin-top:0}.prose p{margin:0 0 17px}.prose li{margin:8px 0}.prose figure{margin:24px 0}.prose svg{width:100%;height:auto;display:block}.prose figcaption{font-size:13px;color:var(--muted)}.related{border-top:2px solid var(--blue);padding-top:18px;align-self:start}.related h2{font-size:17px;margin:0 0 12px}.related a{display:block;margin-bottom:12px;font-size:14px}.practice-case{border-left:3px solid var(--green);padding:4px 0 4px 20px;margin:25px 0}.practice-case h2{font-size:20px;margin:0 0 12px}.note,.calculation-notes{border-left:3px solid #d8a739;padding:10px 16px;background:#fff9e9;color:#625024;font-size:14px;margin:20px 0}.note p:last-child,.calculation-notes p:last-child{margin-bottom:0}.tool-surface{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:36px;border:1px solid var(--line);background:#fff;border-radius:8px;padding:28px;margin-bottom:30px}.fields{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin-bottom:22px}.field{display:block;min-width:0}.field>span{display:block;margin-bottom:6px;font-size:13px;font-weight:650;line-height:1.4}.field input[type=range]{width:100%;accent-color:var(--blue)}.field select{overflow:hidden;text-overflow:ellipsis}.tool-result{min-width:0;border-left:1px solid var(--line);padding-left:30px}.result-value{font-size:34px;font-weight:800;line-height:1.2;overflow-wrap:anywhere}.result-value span{font-size:20px;font-weight:600}.tool-result h2{font-size:18px;margin:22px 0 10px}.calculation-steps{padding-left:22px;font-size:14px}.calculation-steps li{margin-bottom:10px;overflow-wrap:anywhere}.calc-error{margin-top:18px;color:#a3293d;font-size:14px}.check{font-size:14px;padding:10px;border-left:3px solid}.check.pass{background:#edf9f3;color:#08704c}.check.fail{background:#fff0f2;color:#a3293d}.muted{color:var(--muted);font-size:14px}.lab-surface{border:1px solid var(--line);border-radius:8px;background:#fff;padding:24px;margin:20px 0}.lab-controls{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}.lab-diagram{margin:24px 0 12px}.lab-diagram svg{display:block;width:100%;max-height:340px}.lab-diagram text{font:16px Arial,sans-serif;fill:#344054}.lab-diagram figcaption{font-size:14px;color:var(--muted)}.lab-value{font-weight:700}.exam-setup{display:flex;align-items:center;gap:14px;flex-wrap:wrap;border-bottom:1px solid var(--line);padding-bottom:24px;margin-bottom:20px}.exam-setup>.muted{width:100%}.mode-picker{margin:0;padding:0;border:0;display:flex;gap:2px}.mode-picker legend{font-size:13px;color:var(--muted);margin-bottom:5px}.mode-picker label{padding:8px 12px;background:#fff;border:1px solid var(--line);font-size:14px}.mode-picker input{accent-color:var(--blue)}.mode-picker label:has(input:checked){background:#eaf0ff;border-color:#8faeff}.exam-status{display:flex;gap:20px;align-items:center;padding:14px 0;flex-wrap:wrap}.exam-status time{margin-left:auto;font-variant-numeric:tabular-nums;font-weight:800;min-width:55px}.exam-question{padding:20px;margin:0 0 20px;background:#fff;border:1px solid var(--line);border-radius:8px;min-width:0}.exam-question legend{font-weight:700;padding:0 8px;font-size:17px;max-width:100%}.exam-question legend>span{color:var(--blue)}.answer{display:flex;gap:12px;align-items:flex-start;padding:12px;margin-top:9px;border:1px solid var(--line);border-radius:5px;cursor:pointer}.answer input{margin-top:6px;accent-color:var(--blue);flex-shrink:0}.answer:has(input:checked){border-color:#7fa2f1;background:#f1f5ff}.answer.is-right{background:#edf9f3;border-color:#80c4a2}.answer.is-wrong{background:#fff0f2;border-color:#db9ca6}.answer-explanation{padding:15px 0 0;font-size:14px}.answer-explanation p{margin:5px 0}.exam-summary{border-left:4px solid var(--green);padding:18px;background:#eaf8f1;margin:15px 0 25px}.exam-summary h2{margin:0 0 10px}.exam-history{margin-bottom:20px}.exam-history summary{cursor:pointer;font-size:14px}.history-list{padding-left:20px;font-size:14px}.document-list{display:grid;gap:0}.document-item{padding:20px 0;border-top:1px solid var(--line)}.document-item h2{font-size:19px;margin:0 0 8px}.document-item p{font-size:14px;color:var(--muted)}.footer{margin-top:36px;border-top:1px solid var(--line);background:#fff;padding:24px 0;font-size:13px;color:var(--muted)}.footer .wrap{display:flex;justify-content:space-between;gap:24px}.formula{font:600 16px/1.5 ui-monospace,monospace;overflow-wrap:anywhere}.mini-links{display:flex;gap:15px;flex-wrap:wrap;margin-top:15px}
@media(max-width:950px){.catalog-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.article-layout{grid-template-columns:minmax(0,1fr);gap:24px}.related{max-width:780px}.topbar-inner{flex-wrap:wrap;padding-top:14px;gap:8px}.topnav{width:100%;overflow:auto;padding:10px 0;gap:18px}.tool-surface{grid-template-columns:1fr;gap:25px}.tool-result{border-left:0;border-top:1px solid var(--line);padding-left:0;padding-top:24px}}
@media(max-width:560px){.wrap{width:calc(100% - 28px)}h1{font-size:27px}h2{font-size:21px}.page-head{padding-top:18px}.catalog-grid{grid-template-columns:1fr}.catalog-row{align-items:flex-start;flex-direction:column;gap:10px}.catalog-item{padding:18px}.fields{grid-template-columns:1fr}.tool-surface{padding:18px}.lab-controls{grid-template-columns:1fr;gap:14px}.lab-surface{padding:15px}.exam-question{padding:14px}.exam-question legend{font-size:16px}.exam-status{gap:10px;font-size:14px}.result-value{font-size:30px}.footer .wrap{display:block}.exam-setup .button{flex:1}.topnav a{font-size:13px}}
@media(max-width:560px){.topnav{flex-wrap:wrap;overflow:visible;gap:8px 16px}}
.safety-page main>.wrap{width:min(980px,calc(100% - 40px))}
.safety-page .page-head{padding-bottom:10px}
.safety-page .page-head h1{font-size:32px}
.safety-page .note{margin:12px 0 24px;line-height:1.6}
[data-safety-exam] .exam-setup{display:block;padding:0 0 22px;margin:0 0 22px}
.exam-controls{display:flex;align-items:flex-end;justify-content:space-between;gap:20px;flex-wrap:wrap}
[data-safety-exam] .mode-picker{display:block;min-width:0}
.mode-options{display:flex;gap:4px;padding:4px;background:#e9edf4;border-radius:8px}
.mode-options label{position:relative;display:block;padding:0;border:0;background:transparent;border-radius:5px;cursor:pointer}
.mode-options input{position:absolute;inset:0;opacity:0;width:100%;height:100%;margin:0;cursor:pointer}
.mode-options label span{display:flex;align-items:center;justify-content:center;min-height:42px;min-width:128px;padding:8px 20px;font-weight:650;border:1px solid transparent;border-radius:5px}
.mode-options label:has(input:checked){background:var(--surface);color:#184eba;box-shadow:0 1px 3px #17203312}
.mode-options label:has(input:focus-visible){outline:3px solid #7aa2ff;outline-offset:2px}
.exam-actions{display:flex;gap:10px;flex-wrap:wrap}
.exam-actions .button{min-height:50px}
.exam-meta{display:flex;justify-content:space-between;gap:12px 24px;flex-wrap:wrap;margin-top:14px;font-size:13px;color:var(--muted)}
.local-save{display:inline-flex;align-items:center;gap:8px;color:#08704c}
.local-save:before{content:"";width:7px;height:7px;flex-shrink:0;border-radius:50%;background:currentColor}
.local-save.is-unavailable{color:#a3293d}
[data-safety-exam] .exam-history:empty{display:none}
[data-safety-exam] .exam-status{display:block;padding:16px 0 20px;margin-bottom:4px;position:sticky;top:0;z-index:2;background:var(--bg)}
.exam-status-line{display:flex;align-items:center;gap:12px 22px;flex-wrap:wrap;font-size:14px;min-height:28px}
.exam-status-line strong{font-size:16px}
.exam-status-line [data-answered]{color:var(--muted)}
.exam-status-line .progress-percent{margin-left:auto;font-weight:750;font-variant-numeric:tabular-nums;color:#08704c}
.exam-status-line time{margin-left:auto;min-width:64px;text-align:center;padding:2px 8px;border-radius:4px;background:#fff;border:1px solid var(--line)}
.exam-status-line time+.progress-percent{margin-left:0}
.answer-progress{height:6px;background:#dfe5ee;border-radius:3px;overflow:hidden;margin-top:12px}
.answer-progress>span{display:block;width:0;height:100%;background:var(--green);transition:width .15s ease}
[data-safety-exam] .exam-question{padding:24px;margin:0 0 16px}
[data-safety-exam] .exam-question legend{float:left;display:flex;align-items:flex-start;gap:12px;width:100%;padding:0;margin:0 0 18px;line-height:1.5;font-size:17px}
[data-safety-exam] .exam-question legend>span{display:flex;align-items:center;justify-content:center;flex:0 0 30px;min-height:30px;background:#edf2ff;border-radius:5px;font-size:14px;line-height:1.4;font-variant-numeric:tabular-nums}
.answer-list{clear:both;display:grid;gap:8px}
[data-safety-exam] .answer{margin:0;min-height:52px;padding:12px 14px;gap:12px;line-height:1.55;transition:border-color .15s ease}
[data-safety-exam] .answer input{width:17px;height:17px;margin:3px 0 0;accent-color:var(--blue)}
[data-safety-exam] .answer:hover:not(:has(input:disabled)){border-color:#9caecc}
[data-safety-exam] .answer:has(input:focus-visible){outline:3px solid #7aa2ff;outline-offset:2px}
[data-safety-exam] .answer span{min-width:0;overflow-wrap:anywhere}
[data-safety-exam] .answer-explanation{border-top:1px solid var(--line);margin-top:18px;padding-top:15px}
.exam-finish{display:flex;align-items:center;gap:12px 22px;flex-wrap:wrap;padding:8px 0 0}
.exam-finish p{margin:0}
.exam-summary.needs-review{border-color:#c08824;background:#fff6e6}
@media(max-width:560px){
 .safety-page main>.wrap{width:calc(100% - 28px)}
 .safety-page .page-head h1{font-size:26px}
 .exam-controls{gap:14px;align-items:stretch}
 [data-safety-exam] .mode-picker,.mode-options,.exam-actions{width:100%}
 .mode-options label{flex:1}.mode-options label span{min-width:0;padding:8px 12px}
 .exam-actions .button{flex:1;min-height:46px}
 .exam-meta{gap:8px;margin-top:12px}
 [data-safety-exam] .exam-question{padding:16px}
 [data-safety-exam] .exam-question legend{font-size:16px;gap:10px;margin-bottom:16px}
 [data-safety-exam] .answer{font-size:15px;padding:12px;min-height:48px}
 .exam-status-line{gap:8px 12px;font-size:13px}
 .exam-status-line strong{font-size:14px}
 [data-safety-exam] .exam-status{padding:12px 0 16px}
 .exam-finish .button{width:100%}
}
@media(prefers-reduced-motion:reduce){.answer-progress>span,[data-safety-exam] .answer{transition:none}}
@media print{.topbar,.footer,.exam-setup{display:none}.tool-surface,.article-layout{display:block}.tool-result{border:0;padding:0}.wrap{width:100%}body{background:#fff}[data-safety-exam] .exam-status{position:static}.exam-question{break-inside:avoid}}