/* V27 LESSON-FIRST — content is the interface */
.v27-course,.v27-reader{max-width:1320px;margin:auto}
.v27-course{padding:28px 24px 72px}
.v27-course-hero{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:28px;align-items:start;background:#fff;border:1px solid #e5e8ef;border-radius:24px;padding:28px;box-shadow:0 16px 48px rgba(35,44,86,.07)}
.v27-course-main h1{font-size:clamp(34px,4.4vw,58px);line-height:1.02;letter-spacing:-.045em;margin:10px 0 14px}
.v27-domain{font-size:10px;font-weight:850;text-transform:uppercase;letter-spacing:.08em;color:#575bd8}
.v27-lead{font-size:17px;line-height:1.7;color:#596377;max-width:850px}
.v27-course-meta{display:flex;gap:9px;flex-wrap:wrap;margin:18px 0}.v27-course-meta span{font-size:10px;padding:7px 9px;background:#f5f6f9;border:1px solid #e7eaf0;border-radius:999px}
.v27-course-progress{background:#f7f8fb;border:1px solid #e6e9ef;border-radius:17px;padding:16px}.v27-course-progress strong{font-size:12px}
.v27-course-info{display:grid;grid-template-columns:1.2fr .8fr;gap:14px;margin:16px 0}.v27-course-info>section{background:#fff;border:1px solid #e5e8ef;border-radius:20px;padding:20px}.v27-course-info h2,.v27-schedule h2{font-size:22px;letter-spacing:-.025em;margin:0 0 12px}.v27-course-info p,.v27-highlights{font-size:13px;line-height:1.65;color:#5d6678}.v27-highlights{list-style:none;padding:0;margin:0}.v27-highlights li{padding:6px 0}
.v27-schedule{background:#fff;border:1px solid #e5e8ef;border-radius:22px;padding:22px}.v27-heading{display:flex;justify-content:space-between;align-items:end}.v27-heading p{font-size:10px;color:#788193}
.v27-unit{border-top:1px solid #edf0f4;padding:18px 0}.v27-unit:first-of-type{border-top:0}.v27-unit-head>span{font-size:9px;color:#666fe0;font-weight:900;text-transform:uppercase;letter-spacing:.08em}.v27-unit-head h3{font-size:18px;margin:5px 0}.v27-unit-head p{font-size:11px;color:#737d90}
.v27-lesson-list{margin-top:10px;border:1px solid #e8eaf0;border-radius:14px;overflow:hidden}.v27-lesson-list a{display:grid;grid-template-columns:48px 1fr auto;gap:10px;align-items:center;padding:11px 12px;border-top:1px solid #eceef3;text-decoration:none;color:#1e2330;background:#fff}.v27-lesson-list a:first-child{border-top:0}.v27-lesson-list a:hover{background:#f7f8ff}.v27-number{font-size:10px;color:#69738a}.v27-lesson-title{font-size:12px;font-weight:750}.v27-duration{font-size:9px;color:#80889a}.v27-unit-actions{display:flex;gap:8px;margin-top:8px}.v27-unit-actions a{font-size:9px;text-decoration:none;color:#5357d8;font-weight:800}
.v27-references{margin-top:14px;background:#fff;border:1px solid #e5e8ef;border-radius:18px;padding:18px}.v27-references li{font-size:11px;margin:4px 0}

.v27-reader{display:grid;grid-template-columns:240px minmax(0,760px) 210px;gap:22px;padding:24px 18px 80px;align-items:start}
.v27-leftnav{position:sticky;top:82px;max-height:calc(100vh - 100px);overflow:auto;padding:4px 10px 20px}.v27-back{display:block;font-size:10px;font-weight:850;color:#5459d3;text-decoration:none;margin-bottom:14px}.v27-nav-unit{margin:14px 0}.v27-nav-unit strong{display:block;font-size:10px;color:#535d70;margin-bottom:6px}.v27-nav-unit a{display:block;text-decoration:none;color:#70798a;font-size:9px;line-height:1.35;padding:6px 8px;border-radius:8px}.v27-nav-unit a:hover{background:#f0f2f7;color:#212635}.v27-nav-unit a.current{background:#ebeaff;color:#4b49d3;font-weight:850}
.v27-article{background:#fff;border:1px solid #e5e8ef;border-radius:22px;padding:32px 38px;box-shadow:0 12px 40px rgba(36,44,82,.05)}.v27-breadcrumb{font-size:9px;text-transform:uppercase;letter-spacing:.07em;color:#747e91;font-weight:750}.v27-article>h1{font-size:clamp(32px,4vw,48px);line-height:1.08;letter-spacing:-.04em;margin:10px 0 18px}.v27-intro{font-size:17px;line-height:1.75;color:#3e4655;border-left:4px solid #5b5cf0;padding-left:18px;margin:18px 0 28px}
.v27-toc{background:#f7f8fb;border:1px solid #e7eaf0;border-radius:15px;padding:14px 16px;margin:20px 0 30px}.v27-toc strong{font-size:11px}.v27-toc ol{margin:8px 0 0;padding-left:20px}.v27-toc li{font-size:10px;margin:5px 0}.v27-toc a{color:#5055d6;text-decoration:none}
.v27-content-section,.v27-example,.v27-practice,.v27-summary,.v27-terms,.v27-check{margin:34px 0}.v27-article h2{font-size:25px;letter-spacing:-.025em;margin:0 0 13px}.v27-article p,.v27-article li{font-size:15px;line-height:1.78;color:#414a5b}.v27-article ul{padding-left:22px}.v27-article li{margin:6px 0}
.v27-diagram{background:#141923;color:#eaf0ff;border-radius:16px;padding:14px 16px;margin:28px 0;overflow:auto}.v27-diagram figcaption{font-size:9px;color:#9ea9bd;text-transform:uppercase;letter-spacing:.08em;margin-bottom:10px}.v27-diagram pre{font-size:12px;line-height:1.55;margin:0;color:#eaf0ff}
.v27-example{background:#f4f7ff;border:1px solid #dfe5ff;border-radius:17px;padding:18px}.v27-example h2{font-size:19px}.v27-code{background:#121722;color:#edf2ff;border-radius:13px;padding:15px;overflow:auto;font-size:11px;line-height:1.6}
.v27-practice{background:#effaf6;border:1px solid #d4eee4;border-radius:17px;padding:18px}.v27-practice h2{font-size:19px}.v27-summary{border-top:1px solid #e7e9ef;padding-top:20px}.v27-summary ul{list-style:none;padding:0}.v27-summary li{position:relative;padding-left:22px}.v27-summary li:before{content:"✓";position:absolute;left:0;color:#35966d;font-weight:900}
.v27-termgrid{display:grid;grid-template-columns:1fr 1fr;gap:8px}.v27-termgrid article{border:1px solid #e5e8ee;border-radius:13px;padding:12px}.v27-termgrid strong{font-size:11px}.v27-termgrid p{font-size:10px;margin:5px 0 0;line-height:1.5}
.v27-steps{padding-left:24px}.v27-steps li{padding:5px 0}.v27-warning{border-left:4px solid #f1a84f;background:#fff8ec;border-radius:8px;padding:13px 16px;margin:24px 0}.v27-warning strong{font-size:11px}.v27-warning p{font-size:11px;margin:6px 0 0}
.v27-check{border-top:1px solid #e8ebf0;padding-top:22px}.v27-check label{display:block;font-size:11px;padding:5px 0}.v27-complete{display:flex;gap:8px;flex-wrap:wrap;margin-top:36px;padding-top:22px;border-top:1px solid #e7eaf0}.v27-prevnext{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:18px}.v27-prevnext a{border:1px solid #e3e7ee;border-radius:13px;padding:12px;text-decoration:none;color:#202532}.v27-prevnext a:last-child{text-align:right}.v27-prevnext small{font-size:8px;color:#7a8394}.v27-prevnext b{display:block;font-size:10px;margin-top:4px}
.v27-right{position:sticky;top:82px}.v27-side-card{background:#fff;border:1px solid #e5e8ef;border-radius:15px;padding:13px;margin-bottom:10px}.v27-side-card strong{font-size:10px}.v27-side-card p,.v27-side-card li{font-size:8px;color:#727d90}.v27-side-card ol{padding-left:15px}.v27-side-card a{text-decoration:none;color:#5960d7}
@media(max-width:1080px){.v27-reader{grid-template-columns:210px minmax(0,1fr)}.v27-right{display:none}.v27-course-hero{grid-template-columns:1fr}.v27-course-info{grid-template-columns:1fr}}
@media(max-width:760px){.v27-reader{display:block;padding:10px}.v27-leftnav{position:relative;top:auto;max-height:none;background:#fff;border:1px solid #e5e8ef;border-radius:15px;margin-bottom:10px}.v27-leftnav .v27-nav-unit{display:none}.v27-article{padding:22px 18px}.v27-termgrid{grid-template-columns:1fr}.v27-article p,.v27-article li{font-size:14px}.v27-course{padding:16px 12px 60px}.v27-course-hero{padding:20px}.v27-lesson-list a{grid-template-columns:40px 1fr}.v27-duration{display:none}}