:root{--learn-navy:#07194a;--learn-mint:#00c99f;--learn-soft:#f6f8f8;--learn-line:#dfe5e8}.learning-body,.learning-activity-body{background:#fff;color:var(--learn-navy)}.learning-body .site-main,.learning-activity-body .site-main{background:linear-gradient(180deg,#fff 0,#f7fbfa 100%)}.learning-body .topbar,.learning-activity-body .topbar{border-bottom:1px solid #e4e7e8;background:#fff;color:#0a1737;box-shadow:0 5px 20px #10284a0a}.learning-body .site-brand,.learning-activity-body .site-brand{color:#08193e}.learning-body .brand-number,.learning-activity-body .brand-number{color:#00af8a}.learning-body .brand-symbol svg,.learning-activity-body .brand-symbol svg{stroke:#00af8a}.course-catalog{width:min(1500px,calc(100% - 44px));margin:auto;padding:46px 0 90px}.catalog-intro{display:grid;grid-template-columns:auto 1fr 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17px;font-size:1.1rem;line-height:1.7}.chapter-meta{display:flex;justify-content:space-between;margin-top:auto;color:#6c7881;font-size:.78rem;font-weight:800}.chapter-progress{height:5px;margin-top:11px;overflow:hidden;border-radius:10px;background:#e7eaeb}.chapter-progress i,.map-progress i,.question-progress i{display:block;height:100%;border-radius:inherit;background:var(--chapter-accent,#00c99f)}.coming-card{display:grid;min-height:240px;place-items:center;color:#7b8790}.path-page{display:grid;width:min(1300px,calc(100% - 44px));grid-template-columns:420px minmax(0,1fr);gap:55px;margin:auto;padding:70px 0 110px}.path-summary{position:sticky;top:95px;align-self:start;padding:38px;border:2px solid #e1e4e5;border-radius:27px;background:#fff;box-shadow:0 8px 0 #e2e6e6}.back-link{color:#61717e;text-decoration:none;font-weight:800}.path-icon{display:grid;width:105px;height:105px;place-items:center;margin:45px 0 30px;border-radius:32px;background:color-mix(in srgb,var(--chapter-accent) 15%,white);color:var(--chapter-accent);font-size:3.5rem}.path-summary>small{color:var(--chapter-accent);font-weight:900}.path-summary h1{margin:8px 0 15px;font-size:2rem}.path-summary p{color:#67747e;line-height:2}.path-stats{display:flex;gap:25px;margin-top:30px;padding-top:22px;border-top:1px solid #e6eaeb}.path-stats span{display:grid;color:#6d7880}.path-stats b{color:#07194a;font-size:1.25rem}.stage-map>header{padding:18px 30px;border:3px solid color-mix(in srgb,var(--chapter-accent) 70%,white);border-radius:24px;text-align:center;box-shadow:0 7px 0 color-mix(in srgb,var(--chapter-accent) 45%,white)}.stage-map header small{color:var(--chapter-accent);font-weight:900}.stage-map h2{margin:4px 0 12px}.map-progress{height:6px;overflow:hidden;border-radius:8px;background:#e7ebeb}.stage-road{position:relative;width:min(620px,100%);margin:80px auto}.stage-road:before{position:absolute;top:10px;bottom:10px;right:87px;width:7px;border-radius:8px;background:linear-gradient(var(--chapter-accent),#d7dddd);content:""}.stage-node{position:relative;display:flex;align-items:center;gap:35px;margin:0 30px 74px}.stage-node:nth-child(even){margin-right:150px}.node-orbit{position:relative;z-index:2;display:grid;width:120px;height:82px;place-items:center;border-radius:50%;background:color-mix(in srgb,var(--chapter-accent) 12%,white);box-shadow:0 18px 30px color-mix(in srgb,var(--chapter-accent) 20%,transparent)}.node-orbit:before,.node-orbit:after{position:absolute;inset:10px;border:4px solid color-mix(in srgb,var(--chapter-accent) 60%,white);border-radius:50%;content:""}.node-orbit:after{inset:18px;border-width:2px}.node-orbit span{z-index:2;display:grid;width:50px;height:50px;place-items:center;border-radius:17px;background:var(--chapter-accent);color:#fff;font-size:1.25rem;font-weight:900;box-shadow:0 8px 0 color-mix(in srgb,var(--chapter-accent) 70%,#074)}.stage-label{min-width:255px;padding:18px 22px;border:2px solid #e2e5e6;border-radius:21px;background:#fff;box-shadow:0 7px 0 #e1e5e5}.stage-label small{color:#77838c}.stage-label h3{margin:4px 0 12px}.stage-label a{display:block;padding:10px;border-radius:13px;background:var(--chapter-accent);color:#fff;text-align:center;text-decoration:none;font-weight:900}.stage-label>span{color:#929ca2;font-size:.75rem}.stage-node.locked{filter:grayscale(1);opacity:.55}.stage-node.completed .node-orbit span{background:#4a46ee}.activity-shell{display:grid;min-height:calc(100vh - 72px);grid-template:72px 1fr / 280px 1fr;direction:rtl}.activity-top{grid-column:1/-1;display:grid;grid-template-columns:50px 1fr auto;align-items:center;gap:30px;padding:0 35px;border-bottom:1px solid #e1e6e8;background:#fff}.activity-top>a{color:#3c5872;font-size:1.8rem;text-decoration:none}.question-progress{height:14px;overflow:hidden;border-radius:20px;background:#dfe5e8}.activity-top>b{white-space:nowrap}.lesson-rail{grid-row:2;padding:22px 22px;border-left:1px solid #e1e6e8;background:#fbfcfc}.streak-card{display:grid;grid-template-columns:55px 1fr;align-items:center;padding:17px;border:1px solid #efe7da;border-radius:18px;background:#fffbf5}.streak-card span{grid-row:1/3;font-size:2.5rem}.streak-card b{font-size:1.2rem}.streak-card small{color:#68747d}.lesson-rail h2{margin:28px 10px 18px;font-size:1rem;color:#66747f}.rail-stage{position:relative;display:flex;align-items:center;gap:12px;min-height:62px;padding:9px 12px;color:#213755;text-decoration:none;font-weight:800}.rail-stage:not(:last-of-type):after{position:absolute;right:31px;top:46px;width:3px;height:32px;background:#dbe1e4;content:""}.rail-stage 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var(--chapter-accent)}.choice.correct{border-color:#00bf91;background:#e9fff8}.choice.wrong{border-color:#f05e72;background:#fff0f2}.answer-actions{display:flex;justify-content:space-between;gap:16px;margin-top:18px}.hint-button,.check-button{min-height:56px;padding:0 28px;border:2px solid #6257ff;border-radius:15px;background:#fff;color:#5145e9;font:inherit;font-weight:900;cursor:pointer}.check-button{display:grid;min-width:250px;place-items:center;border-color:var(--chapter-accent);background:var(--chapter-accent);color:#fff;text-decoration:none;box-shadow:0 7px 0 color-mix(in srgb,var(--chapter-accent) 70%,#074)}.hint-text,.feedback{margin-top:17px;padding:15px 18px;border-radius:14px;background:#f5f3ff;color:#4b42bf}.feedback{background:#f5f8f8;color:#334a5e}.feedback.success{border-right:5px solid #00bd91}.feedback.error{border-right:5px solid #ef5b70}.feedback h2{margin:0 0 5px;font-size:1rem}.feedback p{margin:0;line-height:1.9}.feedback 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