/* Learning chrome is deliberately scoped; existing formula, lab and bank styles stay untouched. */
.learning-shortcut{display:flex;align-items:center;gap:20px;background:#102c60;color:white;padding:24px 28px;border-radius:18px;margin:24px 0}.learning-shortcut:hover{background:#173d79}.learning-shortcut-icon{display:grid;place-items:center;width:52px;height:52px;flex-shrink:0;border-radius:50%;background:#72e0cc;color:#102c60}.learning-shortcut small{display:block;color:#a9eade;letter-spacing:.1em;font-size:10px;margin-bottom:7px}.learning-shortcut strong{display:block;font-size:22px;line-height:1.3}.learning-shortcut span span{display:block;font-size:13px;color:#d0deee;margin-top:7px}.learning-shortcut>b{margin-left:auto;white-space:nowrap;font-size:14px}.learning-nav-link{border:1px solid #b9cced;background:#e6edfa;margin:9px 0;color:#163f8d!important;gap:10px;font-weight:650}
#learning-path{--lp-navy:#102c60;--lp-blue:#2351b5;--lp-mint:#72e0cc;--lp-text:#16345e;--lp-muted:#536980;--lp-line:#d6e1eb;color:var(--lp-text);font-family:Inter,"Segoe UI",Arial,sans-serif;text-align:left;line-height:1.55;padding:24px;min-width:0}.lp-header{display:flex;align-items:center;justify-content:space-between;gap:26px;background:var(--lp-navy);color:white;border-radius:18px;padding:34px 38px;overflow:hidden}.lp-eyebrow{font-size:9px;letter-spacing:.15em;font-weight:650;color:#b9d5ed}.lp-header h2{font-size:clamp(30px,3.1vw,46px)!important;line-height:1.13!important;letter-spacing:-1.3px;margin:16px 0!important;color:white!important;font-weight:700}.lp-header h2 em{font-style:normal;color:var(--lp-mint)}.lp-header p{font-size:14px;line-height:1.7;color:#c5d8ed;margin:16px 0 0}.lp-header-art{width:155px;flex-shrink:0;text-align:center;color:var(--lp-mint)}.lp-header-art svg{width:100%;fill:currentColor}.lp-header-art span{display:block;font-size:10px;color:#c5d8ed;margin-top:8px}.lp-overview{display:flex;flex-wrap:wrap;gap:10px 26px;padding:20px 4px 25px;border-bottom:1px solid var(--lp-line);font-size:12px;color:var(--lp-muted)}.lp-overview b{color:var(--lp-text);margin-right:5px}.lp-layout{display:grid;grid-template-columns:minmax(280px,1fr) minmax(230px,290px);align-items:start;gap:34px;padding-top:30px}.lp-path-column{min-width:0}.lp-path-intro{margin:0 0 25px}.lp-path-intro h3{font-size:21px;margin:0 0 5px}.lp-path-intro p{font-size:12px;color:var(--lp-muted);margin:0}.lp-stage{margin-bottom:30px}.lp-stage-header{background:#e6effb;padding:20px 23px;border:1px solid #cfddf0;border-radius:13px;position:relative;z-index:1}.lp-stage-header>span{font-size:9px;letter-spacing:.12em;font-weight:700;color:#3c5e94}.lp-stage-header h3{font-size:19px;line-height:1.35;margin:7px 0 5px;color:#102c60}.lp-stage-header p{font-size:12px;color:#536980;margin:0}.lp-chain{list-style:none;padding:24px 0 5px;margin:0;position:relative;isolation:isolate}.lp-chain:before{content:"";position:absolute;left:50%;top:0;bottom:0;border-left:3px dashed #dce5ef;z-index:-1}.lp-node{display:flex;justify-content:center;position:relative;margin:0 auto 23px;transform:translateX(var(--node-offset));max-width:calc(100% - 120px);min-width:150px}.lp-node-control{display:flex;align-items:center;flex-direction:column;text-align:center;background:none;border:none;padding:0;cursor:pointer;font:inherit;color:var(--lp-text);max-width:210px;text-decoration:none}.lp-node-control:disabled{cursor:not-allowed;color:#7b8796;opacity:1}.lp-circle{width:66px;height:63px;border-radius:50%;background:#2351b5;color:#fff;display:grid;place-items:center;box-shadow:0 7px 0 #153a83,0 0 0 7px #f6f9fc;margin-bottom:16px;border:2px solid #416ac1;transition:transform .15s,box-shadow .15s}.lp-circle svg{width:28px;height:28px;fill:currentColor}.lp-node-control:hover .lp-circle{transform:translateY(-2px);box-shadow:0 9px 0 #153a83,0 0 0 7px #f6f9fc}.lp-node-control:focus-visible{outline:3px solid #2351b5;outline-offset:7px;border-radius:8px}.lp-node.locked .lp-circle{background:#e3e9f0;border-color:#e3e9f0;color:#94a3b6;box-shadow:0 7px 0 #c4cfdc,0 0 0 7px #f6f9fc}.lp-node.done .lp-circle{background:#72e0cc;border-color:#72e0cc;color:#102c60;box-shadow:0 7px 0 #3aa990,0 0 0 7px #f6f9fc}.lp-node-caption{font-size:10px;background:#f6f9fc;padding:1px 7px;margin-bottom:3px;color:#536980}.lp-node strong{font-size:13px;font-weight:650;line-height:1.4;background:#f6f9fc;padding:0 5px}.lp-done-label{color:#24755d;font-size:10px;background:#f6f9fc;margin-top:3px}.lp-sidebar{position:sticky;top:28px;display:grid;gap:18px}.lp-progress-card{background:white;border:1px solid var(--lp-line);padding:24px;border-radius:16px}.lp-progress-heading{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-bottom:15px}.lp-progress-heading span{font-size:10px;font-weight:700;letter-spacing:.08em}.lp-progress-heading strong{font-size:24px;color:#2351b5}.lp-progress-card progress{width:100%;height:9px;display:block;appearance:none;border:0;border-radius:20px;overflow:hidden;background:#e9eef5}.lp-progress-card progress::-webkit-progress-bar{background:#e9eef5;border-radius:20px}.lp-progress-card progress::-webkit-progress-value{background:#48bba5;border-radius:20px}.lp-progress-card progress::-moz-progress-bar{background:#48bba5}.lp-progress-card>p{font-size:12px;color:var(--lp-muted);margin:10px 0 22px}.lp-current{border-top:1px solid var(--lp-line);padding-top:20px}.lp-current>span{font-size:9px;letter-spacing:.09em;color:var(--lp-muted)}.lp-current h3{font-size:16px;line-height:1.45;margin:10px 0 18px}.lp-primary,.lp-secondary{display:inline-flex;align-items:center;justify-content:center;gap:10px;padding:13px 19px;border-radius:12px;font:650 13px/1.4 Inter,"Segoe UI",Arial,sans-serif;cursor:pointer;text-decoration:none;border:1px solid #2351b5;background:#2351b5;color:#fff;min-height:46px;transition:background .15s}.lp-primary:hover{background:#183f92;border-color:#183f92;color:#fff}.lp-secondary{background:white;color:#16345e;border-color:#bacce0}.lp-secondary:hover{background:#eef4fb}.lp-primary:focus-visible,.lp-secondary:focus-visible,.lp-text-link:focus-visible,.lp-close:focus-visible,.lp-lesson-tabs a:focus-visible,.lp-resource:focus-visible{outline:3px solid #39a68f;outline-offset:4px}.lp-current .lp-primary{width:100%}.lp-progress-card .lp-local-note{font-size:10px;line-height:1.6;color:#60738b;margin:19px 0 0}.lp-rule-card{background:#e7f6f2;border:1px solid #c2e7de;border-radius:15px;padding:23px}.lp-rule-icon{font-size:28px;line-height:1;color:#348f7c}.lp-rule-card h3{font-size:20px;line-height:1.3;margin:12px 0;color:#16345e}.lp-rule-card p{font-size:12px;color:#42675f;line-height:1.65}.lp-resource{display:flex;align-items:center;justify-content:space-between;gap:15px;padding:18px;border:1px solid var(--lp-line);border-radius:12px;background:#fff;font-size:12px;font-weight:650}.lp-resource small{display:block;font-size:10px;font-weight:400;color:var(--lp-muted);margin-top:5px}.lp-text-link{font-size:12px;color:#2351b5;text-decoration:underline;text-underline-offset:4px}.lp-finish{text-align:center;padding:28px 20px;border:1px dashed #b9cadd;border-radius:16px;background:#edf2f8}.lp-finish>span{font-size:38px;color:#8ca0b9}.lp-finish h3{font-size:20px;margin:10px 0}.lp-finish p{font-size:13px;color:var(--lp-muted)}.lp-finish.finished{border-color:#68bfae;background:#e0f5ef}.lp-finish.finished>span{color:#188d72}
.lp-dialog{box-sizing:border-box;width:min(900px,calc(100vw - 40px));max-height:calc(100dvh - 48px);padding:0;border:1px solid #cedae7;border-radius:18px;background:#f9fbfd;color:#16345e;box-shadow:0 30px 100px #071b4a50;overflow:auto;font-family:Inter,"Segoe UI",Arial,sans-serif;line-height:1.6}.lp-dialog::backdrop{background:#091c3ed9;backdrop-filter:blur(4px)}.lp-dialog-header{display:flex;align-items:flex-start;justify-content:space-between;gap:25px;padding:24px 28px 18px;background:#fff}.lp-dialog-header small{font-size:9px;letter-spacing:.13em;font-weight:700;color:#536980}.lp-dialog-header h2{font-size:22px!important;font-weight:650;line-height:1.35!important;margin:8px 0 0!important;letter-spacing:-.4px;color:#16345e!important}.lp-close{font-size:29px;line-height:1.1;display:grid;place-items:center;flex:0 0 38px;height:38px;border:1px solid #d3dfec;border-radius:10px;background:#f5f8fc;text-decoration:none;color:#16345e}.lp-lesson-tabs{display:flex;background:#fff;border-top:1px solid #e2eaf3;border-bottom:1px solid #d8e2ed;padding:0 28px;gap:25px;font-size:12px;flex-wrap:wrap}.lp-lesson-tabs a,.lp-lesson-tabs>span{padding:13px 0;border-bottom:3px solid transparent;color:#8594a7}.lp-lesson-tabs a{color:#536980}.lp-lesson-tabs [aria-current=step]{border-color:#2351b5;color:#2351b5;font-weight:650}.lp-dialog-body{padding:27px 28px 30px}.lp-video-wrap{background:#102c60;border-radius:12px;overflow:hidden;aspect-ratio:16/9}.lp-video-wrap video{display:block;width:100%;height:100%;object-fit:contain;background:#102c60}.lp-video-meta{display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px;margin-top:13px;font-size:11px;color:#536980}.lp-video-meta a{color:#2351b5;text-decoration:underline;text-underline-offset:3px}.lp-muted{font-size:12px;color:#63768e;line-height:1.65}.lp-video-next{display:flex;align-items:center;justify-content:space-between;gap:28px;padding:24px 0 8px}.lp-video-next h3{font-size:17px;margin:0 0 8px}.lp-video-next p{font-size:12px;color:#536980;max-width:430px;margin:0}.lp-video-next .lp-primary{flex-shrink:0}.lp-support{font-size:12px;border-top:1px solid #d8e2ed;margin-top:22px;padding-top:16px}.lp-support summary{cursor:pointer;color:#2351b5}.lp-support a{color:#2351b5;text-decoration:underline}.lp-pill{font-size:9px;letter-spacing:.1em;color:#2351b5;background:#e7eefb;border:1px solid #ceddf3;border-radius:6px;padding:5px 8px;display:inline-block;font-weight:700}.lp-quiz-intro h3{font-size:23px;line-height:1.35;margin:14px 0 10px;letter-spacing:-.5px}.lp-quiz-intro p{font-size:13px;color:#536980;max-width:650px;margin:0 0 24px}.lp-question{margin:0 0 25px;padding:18px;border:1px solid #d6e1ee;border-radius:13px;background:white;min-width:0}.lp-question-heading{font-size:15px;font-weight:650;line-height:1.55;max-width:100%;min-width:0;margin:0 0 14px;overflow-wrap:anywhere}.lp-question-heading p{margin:0;color:inherit;font:inherit;white-space:normal;overflow-wrap:anywhere}.lp-question-heading>span{display:block;font-size:10px;color:#63768e;margin-bottom:4px;letter-spacing:.1em}.lp-choice{display:flex;align-items:center;gap:12px;position:relative;padding:13px 14px;border:1px solid #d9e3ef;border-radius:9px;background:#fff;font-size:14px;line-height:1.5;margin:10px 0 0;cursor:pointer;overflow-wrap:anywhere}.lp-choice:hover{background:#f4f8fd}.lp-choice:has(input:checked){border-color:#2351b5;background:#eaf1ff;box-shadow:0 0 0 1px #2351b5}.lp-choice:has(input:focus-visible){outline:3px solid #39a68f;outline-offset:3px}.lp-choice input{width:17px;height:17px;accent-color:#2351b5;flex:0 0 17px;margin:0}.lp-choice-letter{display:grid;place-items:center;width:23px;height:23px;flex:0 0 23px;color:#536980;border:1px solid #d6e1ee;border-radius:5px;font-size:10px;font-weight:650}.lp-quiz-submit{display:flex;align-items:center;gap:20px}.lp-quiz-submit>span{font-size:12px;color:#63768e}.lp-form-error,.lp-video-error{padding:14px;background:#fff0e8;color:#8e3b20;border:1px solid #efc6b5;border-radius:8px;font-size:13px}.lp-result-banner{display:flex;gap:18px;align-items:flex-start;border:1px solid #addfd1;border-radius:13px;background:#e6f7f1;padding:22px}.lp-result-banner>span{font-size:35px;color:#21896f;line-height:1}.lp-result-banner h3{font-size:22px;line-height:1.3;margin:0 0 8px}.lp-result-banner p{font-size:13px;margin:5px 0;color:#386b60}.lp-result-banner.retry{background:#fff5e4;border-color:#e8d19d}.lp-result-banner.retry>span,.lp-result-banner.retry p{color:#8b6629}.lp-result-actions{display:flex;flex-wrap:wrap;align-items:center;gap:12px;padding:20px 0 28px}.lp-results>h3{font-size:19px;margin:5px 0 0}.lp-review{border:1px solid #d2e6de;background:#fff;border-radius:12px;padding:20px;margin:18px 0}.lp-review.incorrect{border-color:#e3c7ae}.lp-review-title{display:flex;justify-content:space-between;gap:15px;font-size:10px;letter-spacing:.04em;color:#2d826b}.lp-review.incorrect .lp-review-title{color:#956134}.lp-review h4{font-size:15px;line-height:1.55;margin:13px 0}.lp-review p{font-size:13px;margin:8px 0;color:#536980}.lp-review .lp-explanation{background:#eef5fb;color:#294b70;padding:13px 15px;border-radius:8px;margin-top:15px}.lp-results:focus{outline:none}
@media(min-width:1500px){.lp-layout{grid-template-columns:minmax(320px,1fr) 310px;gap:50px}.lp-header{padding:42px 46px}.lp-header-art{width:195px}}
@media(max-width:1150px){#learning-path{padding:18px}.lp-layout{gap:20px;grid-template-columns:minmax(235px,1fr) 230px}.lp-header{padding:28px}.lp-header-art{width:120px}.lp-progress-card{padding:18px}.lp-node{--node-offset:0px!important;min-width:160px}.lp-node:nth-child(3n+1){transform:translateX(-30px)}.lp-node:nth-child(3n+2){transform:translateX(20px)}.lp-node:nth-child(3n){transform:translateX(35px)}}
@media(max-width:700px){.learning-shortcut{padding:20px;gap:15px;flex-wrap:wrap}.learning-shortcut strong{font-size:19px}.learning-shortcut>b{margin-left:67px}.lp-layout{display:flex;flex-direction:column;gap:24px}.lp-sidebar{position:static;order:-1;width:100%;gap:13px}.lp-rule-card{display:none}.lp-progress-card{padding:18px}.lp-progress-card>p{margin:8px 0 15px}.lp-current{display:grid;grid-template-columns:1fr auto;gap:4px 15px;padding-top:14px}.lp-current>span{grid-column:1}.lp-current h3{margin:3px 0;font-size:13px}.lp-current .lp-primary{grid-column:2;grid-row:1/3;align-self:center;min-height:42px;width:auto;padding:10px 15px}.lp-progress-card .lp-local-note{font-size:10px;margin-top:15px}.lp-resource,.lp-sidebar>.lp-text-link{display:none}.lp-path-column{width:100%}.lp-header{padding:24px;gap:14px}.lp-header-art{display:none}.lp-header h2{font-size:33px!important}.lp-eyebrow{font-size:8px}.lp-header p{font-size:12px}.lp-overview{gap:10px 17px;font-size:11px;padding-bottom:18px}.lp-path-intro h3{font-size:19px}.lp-stage-header h3{font-size:18px}.lp-chain{padding-top:28px}.lp-node{max-width:200px;min-width:0;transform:translateX(var(--node-offset))!important;--node-offset:0px!important}.lp-node:nth-child(3n+1){transform:translateX(-30px)!important}.lp-node:nth-child(3n+2){transform:translateX(20px)!important}.lp-node:nth-child(3n){transform:translateX(40px)!important}.lp-dialog{width:calc(100vw - 16px);max-height:calc(100dvh - 16px);border-radius:14px}.lp-dialog-header{padding:19px 18px 16px;gap:14px}.lp-dialog-header h2{font-size:18px!important}.lp-dialog-header small{font-size:8px}.lp-close{flex-basis:34px;height:34px}.lp-lesson-tabs{padding:0 18px;gap:22px;font-size:11px}.lp-dialog-body{padding:20px 16px}.lp-video-wrap{border-radius:8px}.lp-video-meta{font-size:10px}.lp-video-next{display:block;padding-top:15px}.lp-video-next .lp-primary{margin-top:18px;width:100%}.lp-quiz-intro h3{font-size:21px}.lp-question{padding:12px 10px}.lp-question-heading{font-size:14px;padding:0}.lp-choice{font-size:13px;padding:12px 10px;gap:9px}.lp-choice-letter{display:none}.lp-quiz-submit{flex-direction:column;align-items:stretch;gap:10px}.lp-quiz-submit>span{text-align:center}.lp-result-banner{padding:18px;gap:13px}.lp-result-banner h3{font-size:19px}.lp-result-actions>.lp-primary,.lp-result-actions>.lp-secondary{flex:1 1 180px}.lp-review{padding:16px}.lp-review h4{font-size:14px}}
@media(max-width:400px){#learning-path{padding:12px}.lp-header{padding:22px 18px}.lp-header h2{font-size:30px!important}.lp-current{display:block}.lp-current .lp-primary{margin-top:13px;width:100%}.lp-stage-header{padding:18px}.lp-node:nth-child(3n){transform:translateX(25px)!important}.lp-node:nth-child(3n+1){transform:translateX(-20px)!important}.lp-node:nth-child(3n+2){transform:translateX(10px)!important}}
@media(prefers-reduced-motion:reduce){#learning-path *, .lp-dialog *{transition:none!important;scroll-behavior:auto!important}}
/* Multi-topic route selection and long Russian headings. */
.learning-shortcuts{display:grid;gap:14px;margin:24px 0}.learning-shortcuts .learning-shortcut{margin:0}.learning-shortcut>span:nth-child(2){min-width:0;overflow-wrap:anywhere}.lp-courses{display:flex;flex-wrap:wrap;gap:10px;margin-bottom:20px}.lp-courses a{flex:1 1 150px;border:1px solid #cedcf0;border-radius:11px;background:#fff;padding:12px 15px;font-size:12px;font-weight:650;line-height:1.45;color:#274977;min-width:0;overflow-wrap:anywhere}.lp-courses a[aria-current=page]{border-color:#2351b5;background:#e7efff;color:#163f8d}.lp-courses small{display:block;font-size:9px;font-weight:400;color:#64798f;margin-top:4px}.lp-courses a:focus-visible{outline:3px solid #39a68f;outline-offset:3px}.lp-header>div:first-child{min-width:0}.lp-header h2{overflow-wrap:anywhere}.lp-node-control{max-width:min(210px,100%)}.lp-node strong{overflow-wrap:anywhere}.lp-header p{max-width:600px}
@media(max-width:700px){.lp-courses a{flex-basis:130px}.learning-shortcuts{gap:12px}.learning-shortcuts .learning-shortcut strong{font-size:18px}.learning-shortcuts .learning-shortcut>b{margin-left:0}.learning-shortcuts .learning-shortcut>span:nth-child(2){flex:1 1 150px}.lp-header h2{font-size:clamp(26px,6vw,33px)!important}}

/* Question text belongs inside the card, not in the fieldset border. */
.lp-quiz,.lp-question{box-sizing:border-box;width:100%;max-width:100%;min-width:0}.lp-question{margin-inline:0}.lp-choice{box-sizing:border-box;width:100%;max-width:100%;min-width:0}.lp-choice>span:last-child{min-width:0;flex:1 1 auto;white-space:normal;overflow-wrap:anywhere}.lp-quiz-submit{min-width:0;flex-wrap:wrap}.lp-quiz-submit .lp-primary{max-width:100%;white-space:normal;overflow-wrap:anywhere}.lp-dialog-body,.lp-review,.lp-review p,.lp-review h4{min-width:0;overflow-wrap:anywhere}

.lp-notation{background:#eef5fb;border:1px solid #cedeed;border-radius:10px;padding:13px 16px;font-size:12px;line-height:1.65;color:#294b70;overflow-wrap:anywhere}

/* Keep dismissal separate from the independently scrolling lesson, including narrow screens. */
.lp-dialog{max-height:calc(100dvh - 32px);padding:0;border:0;border-radius:0;background:transparent;box-shadow:none;overflow:visible}
.lp-dialog[open]{display:flex;flex-direction:column;gap:8px}
.lp-dialog-toolbar{display:flex;justify-content:flex-end;flex:0 0 44px;min-height:44px}
.lp-dialog .lp-close{box-sizing:border-box;flex:0 0 44px;width:44px;min-width:44px;height:44px;min-height:44px;padding:0;font-size:30px;line-height:1;border-radius:12px;background:#fff;box-shadow:0 3px 14px #071b4a40}
.lp-dialog-scroll{box-sizing:border-box;min-height:0;max-height:calc(100dvh - 84px);overflow:auto;overscroll-behavior:contain;scrollbar-gutter:stable;border:1px solid #cedae7;border-radius:18px;background:#f9fbfd;box-shadow:0 30px 100px #071b4a50}
@media(max-width:700px){.lp-dialog{width:calc(100vw - 16px);max-height:calc(100dvh - 24px)}.lp-dialog-scroll{max-height:calc(100dvh - 76px);border-radius:14px}}

/* Font-independent cross: both strokes share the exact centre of the 44px target. */
.lp-dialog .lp-close>span{position:relative;display:block;width:20px;height:20px;font-size:0;line-height:0}
.lp-dialog .lp-close>span::before,.lp-dialog .lp-close>span::after{content:"";position:absolute;left:0;top:9px;width:20px;height:2px;border-radius:1px;background:currentColor;transform-origin:50% 50%;transform:rotate(45deg)}
.lp-dialog .lp-close>span::after{transform:rotate(-45deg)}