.course-shell{position:relative;border:1px solid var(--line);border-radius:30px;background:linear-gradient(150deg,color-mix(in srgb,var(--paper) 98%,transparent),color-mix(in srgb,var(--paper-soft) 82%,transparent));box-shadow:var(--shadow);overflow:hidden}.course-shell::before{content:"";position:absolute;inset:0;pointer-events:none;opacity:.34;background-image:radial-gradient(color-mix(in srgb,var(--brand) 42%,transparent) 1px,transparent 1px),radial-gradient(color-mix(in srgb,var(--blue) 14%,transparent) 28%,transparent 29%);background-size:24px 24px,330px 330px}.course-heading{position:relative;z-index:1;padding:25px 28px 17px;border-bottom:1px solid var(--line)}.course-heading h2{margin:0;font-size:20px}.course-heading p{margin:5px 0 0;color:var(--muted);font-size:14px}.course-map{position:relative;z-index:1;max-height:min(740px,calc(100dvh - 210px));min-height:580px;overflow-y:auto;overscroll-behavior:contain;padding:34px 24px 70px;scrollbar-width:thin;scrollbar-color:var(--brand) transparent}.topic-route{position:relative;display:grid;grid-template-columns:156px minmax(0,1fr);gap:25px;align-items:start;padding:18px 0 74px}.topic-route:not(:last-child)::after{content:"";position:absolute;left:76px;bottom:10px;height:64px;border-left:5px dashed var(--road)}.topic-marker{position:sticky;top:10px;border:5px solid var(--paper);border-radius:48% 52% 53% 47% / 58% 47% 53% 42%;min-height:122px;padding:14px 10px;background:linear-gradient(145deg,var(--brand),var(--violet));color:#fff;display:grid;place-content:center;gap:5px;text-align:center;box-shadow:0 10px 0 color-mix(in srgb,var(--ink) 11%,transparent),0 16px 25px color-mix(in srgb,var(--ink) 17%,transparent)}.topic-marker[data-topic="fractions"]{background:linear-gradient(145deg,#2ebd8c,#1a9074)}.topic-marker[data-topic="calc"]{background:linear-gradient(145deg,#6388ef,#5062d3)}.topic-marker[data-topic="percent"]{background:linear-gradient(145deg,#f5b53c,#e08440)}.topic-marker[data-topic="equation"]{background:linear-gradient(145deg,#f68579,#d64f76)}.topic-marker[data-topic="formula"]{background:linear-gradient(145deg,#49b9d4,#2785ad)}.topic-marker span{font-size:10px;font-weight:850;letter-spacing:.1em;opacity:.85}.topic-marker strong{font-size:18px;line-height:1.05}.topic-marker small{font-size:11px;opacity:.9}.topic-marker.locked{filter:grayscale(.85);opacity:.55}.topic-track{position:relative;display:grid;gap:18px;padding:4px 0 10px}.topic-track::before{content:"";position:absolute;left:38px;top:34px;bottom:34px;width:5px;border-radius:6px;background:repeating-linear-gradient(to bottom,var(--road) 0 12px,transparent 12px 24px)}.course-island{position:relative;z-index:1;display:grid;grid-template-columns:58px minmax(0,1fr) auto;align-items:center;gap:12px;min-height:70px;border:1px solid var(--line);border-radius:20px;background:var(--paper);color:var(--ink);padding:10px 15px;text-align:left;box-shadow:var(--shadow-soft);transition:transform .15s,border .15s,opacity .15s}.course-island:hover:not(.locked){border-color:var(--brand);transform:translateX(4px)}.course-island:nth-child(3n){margin-left:22px}.course-island:nth-child(3n+2){margin-left:9px}.island-icon{display:grid;place-items:center;width:46px;height:46px;border-radius:16px;background:color-mix(in srgb,var(--brand) 11%,var(--paper));color:var(--brand-deep);font-size:20px;font-weight:900}.course-island.star .island-icon{background:color-mix(in srgb,var(--amber) 18%,var(--paper));color:var(--amber)}.course-island.exam .island-icon{background:color-mix(in srgb,var(--coral) 18%,var(--paper));color:var(--coral)}.course-island strong{display:block;font-size:15px}.course-island small{display:block;margin-top:3px;color:var(--muted);font-size:12px;font-weight:650}.island-progress{display:flex;gap:3px}.island-progress i{width:10px;height:10px;border-radius:50%;background:var(--line)}.island-progress i.done{background:var(--mint)}.course-island.locked{opacity:.5;cursor:not-allowed;box-shadow:none}.course-island.locked .island-icon{background:var(--paper-soft);color:var(--muted)}.course-island.complete{border-color:color-mix(in srgb,var(--mint) 52%,var(--line))}.topic-seal{margin:8px 0 0 18px;color:var(--muted);font-size:12px;font-weight:750}.lesson-definition{margin:0 0 13px;border:1px solid var(--line);border-radius:17px;background:var(--paper-soft);padding:16px;line-height:1.55}.lesson-rules{display:grid;gap:9px;margin:14px 0}.lesson-rule{display:flex;gap:10px;align-items:flex-start}.lesson-rule b{display:grid;place-items:center;flex:none;width:26px;height:26px;border-radius:9px;background:color-mix(in srgb,var(--brand) 14%,var(--paper));color:var(--brand-deep);font-size:12px}.task-status{display:flex;align-items:center;justify-content:space-between;gap:12px;margin:0 0 10px;color:var(--muted);font-size:12px;font-weight:800}.task-status .stars{color:var(--amber);font-size:15px;letter-spacing:2px}.task-help{border:1px solid var(--line);border-radius:12px;background:var(--paper-soft);color:var(--brand-deep);width:37px;height:37px;font-weight:900;font-size:18px}.task-nav{display:flex;justify-content:space-between;gap:9px;margin-top:16px}.task-nav .secondary{border:1px solid var(--line);border-radius:13px;background:var(--paper-soft);color:var(--ink);padding:10px 13px;font-weight:800}.island-actions{display:grid;gap:9px;margin-top:16px}.island-actions .secondary{border:1px solid var(--line);border-radius:13px;background:var(--paper-soft);color:var(--brand-deep);padding:11px 13px;font-weight:800}.exam-notice{border-radius:15px;background:color-mix(in srgb,var(--coral) 13%,var(--paper));padding:13px;color:color-mix(in srgb,var(--coral) 80%,var(--ink));font-size:13px;line-height:1.45}.account-sync-note{position:relative;z-index:1;display:flex;align-items:center;justify-content:center;gap:8px;margin:17px auto 0;color:var(--muted);font-size:12px}.account-sync-note b{color:var(--brand-deep)}@media(max-width:720px){.course-shell{border-radius:24px}.course-heading{padding:19px 18px 13px}.course-heading p{font-size:12px}.course-map{max-height:calc(100dvh - 190px);min-height:530px;padding:24px 11px 48px}.topic-route{grid-template-columns:104px minmax(0,1fr);gap:12px;padding-bottom:58px}.topic-route:not(:last-child)::after{left:51px;height:49px}.topic-marker{min-height:94px;border-width:4px;padding:9px 6px}.topic-marker strong{font-size:14px}.topic-marker small{font-size:9px}.topic-track{gap:13px}.topic-track::before{left:27px}.course-island{grid-template-columns:43px minmax(0,1fr);gap:9px;min-height:64px;padding:9px 10px}.course-island:nth-child(3n),.course-island:nth-child(3n+2){margin-left:0}.island-icon{width:37px;height:37px;border-radius:13px;font-size:16px}.course-island strong{font-size:13px}.course-island small{font-size:10px}.island-progress{grid-column:2;justify-content:flex-start}.island-progress i{width:8px;height:8px}.topic-seal{margin-left:0;font-size:11px}.task-nav{flex-wrap:wrap}.task-nav .button,.task-nav .secondary{flex:1}.island-actions{grid-template-columns:1fr}.account-sync-note{padding:0 10px;text-align:center}}