.learning-host{max-width:1280px;margin:auto;padding:64px 24px 88px}
.learning-page-heading{max-width:850px;margin-bottom:48px}.learning-page-heading h1{font-size:clamp(36px,4.6vw,60px);margin:16px 0 22px}.learning-page-heading>p{color:var(--text-muted);font-size:18px;margin-bottom:20px}
.free-label{display:inline-block;color:var(--text);font-size:13px;background:var(--highlight-soft);padding:4px 10px;border-radius:4px}
.catalog-course{display:grid;grid-template-columns:minmax(220px,.8fr) 1.2fr;gap:44px;align-items:center;padding:32px 0;border-block:1px solid var(--border);text-decoration:none}.catalog-art{padding:12px}.catalog-copy h3{font-size:30px;margin:16px 0}.catalog-copy>p{font-size:17px;color:var(--text-muted);max-width:560px}.catalog-meta{display:flex;gap:16px;flex-wrap:wrap;margin:24px 0;font-size:13px;color:var(--text-muted)}
.lab-cards:has(.catalog-course){display:block}.catalog-course:hover .plain-link{color:var(--accent-text);border-color:var(--accent-text)}
.enroll-actions{display:flex;align-items:center;gap:16px;flex-wrap:wrap;margin-top:28px}.enroll-actions>p{flex-basis:100%;font-size:14px}.course-personal-progress{color:var(--text-muted)}
.outline-intro{margin:22px 0 28px;color:var(--text-muted)}.chapter{border:0;border-bottom:1px solid var(--border);padding:0;margin:0;border-radius:0;background:transparent;scroll-margin-top:100px}.chapter>summary{display:flex;align-items:center;gap:14px;padding:19px 0;list-style:none;font-size:16px;font-weight:550}.chapter>summary::-webkit-details-marker{display:none}.chapter>summary>span:first-child{font-size:12px;color:var(--text-muted);font-weight:400}.chapter-chevron{margin-left:auto;transition:transform .15s}.chapter:not([open]) .chapter-chevron{transform:rotate(-90deg)}.chapter>div{padding-bottom:12px}
.unit-row{display:flex;gap:12px;align-items:center;text-decoration:none;padding:11px 14px;border-radius:5px;font-size:14px}.unit-row:hover{background:var(--surface-subtle)}.unit-row[aria-current=page]{background:var(--highlight-soft);font-weight:550}.unit-marker{color:var(--text-muted)}.unit-marker.is-complete{color:var(--accent-text)}.unit-row-label{margin-left:auto;font-size:12px;color:var(--text-muted)}
.classroom-host{max-width:1380px;margin:auto;padding:36px 24px 80px}.classroom{display:grid;grid-template-columns:280px minmax(0,1fr);gap:64px}.classroom-outline{position:sticky;top:108px;align-self:start;max-height:calc(100vh - 130px);overflow:auto;padding-right:12px}.classroom-outline h2{font-size:23px;line-height:1.4;margin:24px 0 12px}.classroom-outline>p{font-size:13px;color:var(--text-muted)}.classroom-outline nav{margin:24px 0}.classroom-outline .chapter>summary{font-size:14px;gap:9px}.classroom-outline .chapter{margin:0}.classroom-outline .unit-row{font-size:13px}.classroom-lesson{min-width:0;max-width:810px}.lesson-heading{border-bottom:1px solid var(--border);padding-bottom:30px;margin-bottom:30px}.lesson-heading h1{font-size:clamp(30px,3.7vw,46px);margin:16px 0 20px;line-height:1.3}.lesson-heading>p:last-child{font-size:17px;color:var(--text-muted)}
.lesson-enroll{display:flex;align-items:center;justify-content:space-between;gap:22px;padding:18px 20px;margin:24px 0 36px;background:var(--highlight-soft);border-radius:6px;font-size:14px}.lesson-enroll .button{flex-shrink:0;min-height:40px}
.lesson-body{font-size:17px;line-height:1.9}.lesson-body h2{font-size:28px;line-height:1.4;margin:32px 0 20px}.lesson-body h3{font-size:20px;line-height:1.45;margin-bottom:16px}.lesson-body>p{margin:22px 0}.lesson-body pre{overflow:auto;max-width:100%;background:var(--surface-subtle);border:1px solid var(--border);border-radius:6px;padding:22px;font-size:13px;line-height:1.75}.lesson-body code{font-family:ui-monospace,Consolas,monospace}.lesson-body dl{display:grid;grid-template-columns:1fr 1fr;gap:12px 24px;padding:22px;background:var(--surface-subtle);border-radius:6px}.lesson-body dd{margin:0;overflow-wrap:anywhere}.lesson-body .code-toolbar{flex-wrap:wrap;gap:14px;font-size:13px}.lesson-table{overflow:auto;margin:32px 0}.lesson-table table{width:100%;border-collapse:collapse;text-align:left;background:transparent}.lesson-table td,.lesson-table th{padding:12px 18px;border-bottom:1px solid var(--border)}.lesson-table th{background:var(--surface-subtle);font-weight:550;font-size:14px}
.lesson-prompt{border-left:3px solid var(--highlight);padding:22px 26px;background:var(--highlight-soft);margin:30px 0}.lesson-note{font-size:13px;color:var(--text-muted)}.input-example{border:0;padding:0;background:transparent}.input-example>summary{font-size:14px;text-decoration:underline;text-underline-offset:4px}
.lesson-quiz{border:0;padding:0;margin:28px 0}.lesson-quiz legend{font-size:14px;margin-bottom:14px}.lesson-quiz label{display:flex;align-items:flex-start;gap:12px;padding:16px;margin:10px 0;border:1px solid var(--border);border-radius:6px;font-size:16px;cursor:pointer}.lesson-quiz label:has(input:checked){background:var(--highlight-soft);border-color:#A98C4C}.lesson-quiz input{flex-shrink:0;width:18px;height:18px;margin-top:5px;accent-color:var(--accent-text)}.quiz-explanation{border-left:3px solid var(--highlight);padding:20px 24px;margin-top:24px;background:var(--highlight-soft)}
.lesson-completion{margin:42px 0 28px}.learning-feedback{font-size:14px;margin-top:12px;color:var(--accent-text)}.learning-feedback:empty{display:none}.lesson-pagination{display:flex;justify-content:space-between;align-items:center;gap:16px;padding-top:26px;border-top:1px solid var(--border)}.lesson-video{aspect-ratio:16/9;min-height:200px;margin:28px 0}.lesson-video iframe{width:100%;height:100%;border:0}
.learning-tabs{display:flex;gap:24px;border-bottom:1px solid var(--border);margin-bottom:26px}.learning-tabs button{padding:12px 2px;text-decoration:none;border-bottom:2px solid transparent}.learning-tabs button[aria-pressed=true]{border-bottom-color:var(--accent-text);color:var(--text);font-weight:550}.enrolled-course{padding:30px 0 36px;border-bottom:1px solid var(--border)}.enrolled-course h2{font-size:28px;margin:18px 0 26px}.enrolled-course progress{width:min(480px,100%);height:7px;display:block;accent-color:var(--action);margin-bottom:12px}.enrolled-course>p{font-size:14px;color:var(--text-muted)}.enrolled-next{margin:18px 0 24px}.learning-empty{padding:36px 0;color:var(--text-muted)}
@media(max-width:1100px){.desktop-nav{gap:18px}.classroom{gap:32px;grid-template-columns:240px minmax(0,1fr)}.classroom-outline .unit-row-label{display:none}}
@media(max-width:760px){.learning-host{padding:40px 20px 56px}.learning-page-heading{margin-bottom:32px}.learning-page-heading>p{font-size:16px}.catalog-course{grid-template-columns:1fr;gap:20px;padding:20px 0 32px}.catalog-art{max-width:380px;margin:auto}.catalog-copy h3{font-size:26px}.catalog-copy>p{font-size:16px}.catalog-meta{gap:10px}.classroom-host{padding:20px 20px 52px}.classroom{display:flex;flex-direction:column;gap:30px}.classroom-outline{position:static;max-height:none;overflow:visible;padding:0;width:100%;border-bottom:1px solid var(--border);padding-bottom:24px}.classroom-outline h2{font-size:20px;margin:18px 0 8px}.classroom-outline nav{margin:16px 0}.classroom-outline .unit-row-label{display:block}.lesson-heading h1{font-size:32px}.lesson-body{font-size:16px}.lesson-body h2{font-size:25px}.lesson-enroll{align-items:flex-start;flex-direction:column;gap:14px;padding:16px}.lesson-body dl{grid-template-columns:1fr;gap:6px;padding:16px}.lesson-body dd{margin-bottom:10px}.lesson-body pre{padding:14px;font-size:12px}.lesson-prompt{padding:18px}.lesson-pagination .button{font-size:13px}.enrolled-course h2{font-size:24px}.enroll-actions{align-items:flex-start}.course-overview .course-intro h1{font-size:36px}}

.outline-toggle{display:none;background:transparent;border:0;border-bottom:1px solid var(--border);padding:8px 0;min-height:44px;color:var(--text);font:inherit;font-size:14px;cursor:pointer}.outline-toggle>span{margin-left:10px}.outline-toggle[aria-expanded=false]>span{display:inline-block;transform:rotate(-90deg)}
@media(max-width:760px){.outline-toggle{display:inline-flex;align-items:center;margin:18px 20px 0 0}.classroom-outline>nav[hidden]{display:none}}
.enroll-actions[aria-busy=true] [data-enroll],[data-classroom][aria-busy=true] [data-unit-marker],[data-learning-course][aria-busy=true] [data-edit-progress]{visibility:hidden}
[data-my-learning][aria-busy=true] [data-enrolled-courses]{min-height:160px}