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p{font-size:1.1rem;color:var(--text-color);opacity:.7}.course-not-enrolled{max-width:1200px;margin:40px auto;padding:20px}.course-showcase{display:grid;grid-template-columns:1fr 1fr;gap:40px;align-items:start}.course-image-container{position:sticky;top:100px}.course-image-large{width:100%;border-radius:20px;box-shadow:0 10px 40px rgba(0,0,0,.2);transition:transform .3s ease}.course-image-large:hover{transform:scale(1.02)}.course-info-card{background:var(--glass-bg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);border:1px solid var(--glass-border);border-radius:20px;padding:32px;box-shadow:var(--glass-shadow-strong)}.course-title-section{margin-bottom:24px}.course-title-main{font-size:2.5rem;font-weight:700;color:var(--text-color);margin:0 0 12px 0;line-height:1.2}.course-rating{display:inline-flex;align-items:center;gap:8px;background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);color:#fff;padding:8px 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(max-width:1024px){.settings-btn{top:70px;right:15px;width:45px;height:45px;font-size:18px}.course-showcase{grid-template-columns:1fr;gap:30px}.course-image-container{position:relative;top:0}}@media (max-width:768px){.settings-btn{top:65px;right:10px;width:40px;height:40px;font-size:16px}.settings-content{width:95%}.settings-header{padding:16px 20px}.settings-header h2{font-size:1.3rem}.settings-body{padding:20px}.setting-item{flex-direction:column;align-items:flex-start;gap:12px}.setting-item:has(#shortcuts-btn){display:none}.setting-action-btn{width:100%;justify-content:center}.progress-container{padding:12px 16px;margin-bottom:16px}.course-not-enrolled{padding:15px;margin:20px auto}.course-info-card{padding:24px}.course-title-main{font-size:2rem}.course-meta{grid-template-columns:1fr}.welcome-icon{font-size:48px}.welcome-message h3{font-size:1.5rem}.welcome-message p{font-size:1rem}}@media (max-width:480px){.settings-btn{top:60px;right:8px;width:36px;height:36px;font-size:14px}.settings-header h2{font-size:1.1rem}.setting-info{gap:12px}.setting-icon{font-size:22px}.setting-info h3{font-size:1rem}.setting-info p{font-size:.85rem}.progress-container{padding:10px 12px}.progress-label{font-size:.9rem}.progress-percentage{font-size:1rem}.course-title-main{font-size:1.6rem}.course-description-card{padding:16px}.course-description-card h2{font-size:1.2rem}.course-description-card p{font-size:.95rem}.enroll-btn-primary,.enroll-btn-secondary{padding:14px 24px;font-size:1rem}}[data-theme=dark] .settings-header{background:linear-gradient(135deg,#2d1b69 0,#1a3a6e 100%)}[data-theme=dark] .settings-content{background:var(--glass-bg);border-color:var(--glass-border);box-shadow:var(--glass-shadow-strong)}[data-theme=dark] .setting-item{background:rgba(255,255,255,.06);border-color:rgba(255,255,255,.1);box-shadow:0 2px 8px rgba(0,0,0,.25),inset 0 1px 0 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.content-browser{background:var(--glass-bg);border-color:var(--glass-border)}[data-theme=dark] .browser-top{background:rgba(255,255,255,.04);border-bottom-color:rgba(255,255,255,.08)}[data-theme=dark] .enroll-btn-secondary{background:rgba(255,255,255,.07);border-color:rgba(106,17,203,.45);color:var(--text-color);box-shadow:0 2px 10px rgba(0,0,0,.2),inset 0 1px 0 rgba(255,255,255,.06)}.trademark-notice{display:flex;align-items:flex-start;gap:14px;background:rgba(255,193,7,.1);border:1px solid rgba(255,193,7,.4);border-left:4px solid #ffc107;border-radius:12px;padding:16px 20px;margin-top:24px;color:var(--text-color)}.trademark-notice>i{font-size:1.2rem;color:#ffc107;margin-top:2px;flex-shrink:0}.trademark-notice-text p{margin:0 0 6px 0;font-size:.88rem;line-height:1.55}.trademark-notice-text p:last-child{margin-bottom:0}[data-theme=dark] .trademark-notice{background:rgba(255,193,7,.08);border-color:rgba(255,193,7,.3)}.desktop-tab-interface{display:none;flex-direction:column;flex-shrink:0;position:relative;z-index:20;width:100%;background:var(--glass-bg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);border:1px solid var(--glass-border);padding-top:6px;box-sizing:border-box;border-radius:12px;box-shadow:var(--glass-shadow);transition:box-shadow .3s ease}.desktop-tab-interface.is-stuck{position:fixed;left:50%;transform:translateX(-50%);top:var(--menubar-height,70px);width:min(1240px,100%);z-index:200;box-shadow:0 6px 28px rgba(0,0,0,.14);will-change:transform;animation:tab-bar-fly-up .42s cubic-bezier(.16,1,.3,1) both}@keyframes tab-bar-fly-up{from{transform:translateX(-50%) translateY(-100%);opacity:0}to{transform:translateX(-50%) translateY(0);opacity:1}}.desktop-tab-interface.is-stuck.animation-done{will-change:auto}.desktop-tab-interface.is-stuck.scrolled{box-shadow:0 8px 32px 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0;background:rgba(0,0,0,.05);color:var(--text-color);font-size:12px;cursor:pointer;flex-shrink:0;user-select:none;opacity:.7;border:1px solid transparent;border-bottom:none;position:relative;transition:background .2s,opacity .2s,height .15s,transform .16s ease;box-sizing:border-box;will-change:transform}.tab-item:hover{background:rgba(0,0,0,.09);opacity:.9}.tab-item.active{background:var(--bg-color);border-color:rgba(0,0,0,.1);border-bottom-color:var(--bg-color);opacity:1;height:40px;margin-bottom:-1px;z-index:2}[data-theme=dark] .tab-item{background:rgba(255,255,255,.05)}[data-theme=dark] .tab-item:hover{background:rgba(255,255,255,.09)}[data-theme=dark] .tab-item.active{background:var(--bg-color);border-color:rgba(255,255,255,.1);border-bottom-color:var(--bg-color)}.tab-icon{font-size:14px;flex-shrink:0;line-height:1}.tab-title{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;font-size:12px;font-weight:500}.tab-completed-check{font-size:11px;color:#22c55e;flex-shrink:0;line-height:1}.tab-close{width:18px;height:18px;border-radius:50%;background:0 0;border:none;cursor:pointer;display:flex;align-items:center;justify-content:center;font-size:11px;color:inherit;opacity:0;padding:0;flex-shrink:0;font-family:inherit;line-height:1;transition:opacity .2s,background .2s}.tab-item.active .tab-close,.tab-item:hover .tab-close{opacity:.55}.tab-close:hover{opacity:1!important;background:rgba(0,0,0,.12)}[data-theme=dark] .tab-close:hover{background:rgba(255,255,255,.15)}.tab-item.dragging{opacity:.65;cursor:grabbing;transform:scale(.95) rotate(2deg);box-shadow:0 16px 40px rgba(0,0,0,.2);z-index:100;transition:opacity .15s 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