html{scroll-behavior:smooth;overflow-x:hidden;max-width:100vw}*,::after,::before{box-sizing:border-box}*{-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}@media (min-width:769px){.collapse-btn,.content-view-enrolled,.sidebar{will-change:transform;backface-visibility:hidden;transform:translateZ(0)}}:root{--bg-color:#f4f4f9;--text-color:#333;--border-color:#ddd;--title-bar-bg:#007bff;--title-bar-text:white;--btn-bg-color:linear-gradient(135deg, #007bff 0%, #0056b3 100%);--btn-hover-color:linear-gradient(135deg, #0056b3 0%, #007bff 100%);--swal-bg-color:#f0f0f0;--plyr-color-main:#3a5af2;--plyr-video-control-color:#e8ffba;--sidebar-collapsed-width:80px}[data-theme=dark]{--bg-color:#181a1b;--text-color:#e0e0e0;--border-color:#333;--title-bar-bg:#1f1f1f;--title-bar-text:#f9f9f9;--btn-bg-color:linear-gradient(135deg, #0056b3 0%, #007bff 100%);--btn-hover-color:linear-gradient(135deg, #007bff 0%, #0056b3 100%);--swal-bg-color:#333}body{font-family:Poppins,sans-serif;background-color:var(--bg-color);color:var(--text-color);overflow-x:hidden;overflow-y:auto;transition:background-color .3s,color .3s;margin:0;padding:0;padding-top:var(--menubar-height,70px);display:flex;flex-direction:column;min-height:100vh;width:100%;max-width:100vw}main{max-width:1200px;margin:0 auto;padding:20px;width:100%;box-sizing:border-box}.course-header{margin-bottom:20px;max-width:100%;box-sizing:border-box}.course-description,.course-details{max-width:100%;padding:20px;box-sizing:border-box;overflow-wrap:break-word;word-wrap:break-word}.course-description h2,.course-details h2{word-wrap:break-word;overflow-wrap:break-word}.course-description p,.course-details p,.course-details ul{word-wrap:break-word;overflow-wrap:break-word}.course-content-enrolled{display:flex;flex-direction:column;min-height:80vh;background:var(--bg-color);width:100%;box-sizing:border-box}.course-main-container{display:flex;flex:1;box-shadow:0 10px 30px rgba(0,0,0,.1);border-radius:12px;overflow:hidden}.course-image-small{border-radius:50px;width:25%;max-width:200px;height:auto;justify-content:center;align-items:center;object-fit:contain}.header-content{width:100%;display:flex;justify-content:space-between;align-items:center;background-color:var(--title-bar-bg);color:var(--title-bar-text);padding:1px 20px;font-size:1.2rem;box-shadow:0 2px 5px rgba(0,0,0,.1);margin-top:0;z-index:1;box-sizing:border-box;overflow:hidden}.header-content .course-title,.header-content h1{word-wrap:break-word;overflow-wrap:break-word;hyphens:auto;max-width:100%}.sidebar{border-radius:50px;width:25%;min-width:200px;overflow:hidden;background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);color:#fff;padding:30px;display:flex;flex-direction:column;box-shadow:10px 0 20px rgba(0,0,0,.1);position:relative;z-index:1;box-sizing:border-box;will-change:width,min-width,padding}.sidebar.collapsed{width:var(--sidebar-collapsed-width);min-width:var(--sidebar-collapsed-width);padding:30px 10px;align-items:center;overflow:hidden}.sidebar.collapsed~.content-view-enrolled{width:calc(100% - var(--sidebar-collapsed-width));margin-left:0}.sidebar{transition:width .5s cubic-bezier(.25, .46, .45, .94),min-width .5s cubic-bezier(.25, .46, .45, .94),padding .5s cubic-bezier(.25, .46, .45, .94)}.sidebar h2{font-size:24px;font-weight:700;margin-bottom:40px;text-transform:uppercase;transition:opacity .5s cubic-bezier(.25, .46, .45, .94),visibility .5s cubic-bezier(.25, .46, .45, .94)}.sidebar.collapsed h2{opacity:0;visibility:hidden}.sidebar.collapsed p{font-size:14px;justify-content:center;padding:0;text-align:center;margin:0;opacity:0;visibility:hidden}.sidebar-nav ul{list-style:none;padding:0;transition:opacity .5s cubic-bezier(.25, .46, .45, .94),visibility .5s cubic-bezier(.25, .46, .45, .94)}.sidebar.collapsed .sidebar-nav ul{opacity:1;visibility:visible}.sidebar-nav ul li{margin-bottom:20px}.sidebar-nav ul li a{text-decoration:none;color:#fff;font-size:18px;display:flex;align-items:center;padding:10px 15px;border-radius:8px;transition:background-color .3s ease,font-size .5s cubic-bezier(.25, .46, .45, .94),padding .5s cubic-bezier(.25, .46, .45, .94)}.sidebar-nav ul li a:hover{background-color:rgba(255,255,255,.2)}.file-emoji{margin-right:8px;font-size:18px;transition:font-size .5s cubic-bezier(.25, .46, .45, .94)}.file-name{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;transition:opacity .5s cubic-bezier(.25, .46, .45, .94)}.sidebar-nav ul li a.active{background-color:rgba(255,255,255,.2);color:#fff}.sidebar.collapsed ul li a{font-size:14px;justify-content:center;padding:5px}.sidebar.collapsed ul li a.active{width:50px}.sidebar.collapsed .like-dislike{display:flex;flex-direction:column;align-items:center;padding:0}.sidebar.collapsed .like-dislike button{margin:0}.sidebar.collapsed .likes-count{display:none}.sidebar.collapsed ul li a span:not(.file-emoji):not(.material-check){display:none;opacity:0}.sidebar.collapsed ul li a .file-emoji{display:inline;font-size:24px;transition:font-size .5s cubic-bezier(.25, .46, .45, .94)}.sidebar.collapsed ul li a .material-check{display:flex}.collapse-btn{position:absolute;top:10px;left:50%;transform:translateX(-50%);background:rgba(255,255,255,.2);border-radius:8px;display:flex;align-items:center;justify-content:center;border:none;color:#fff;font-size:24px;padding:8px 12px;cursor:pointer;transition:transform .5s cubic-bezier(.25, .46, .45, .94),left .5s cubic-bezier(.25, .46, .45, .94),top .3s ease,right .3s ease,background .3s ease,box-shadow .3s ease;z-index:10}.collapse-btn:hover{background:rgba(255,255,255,.3)}.sidebar.collapsed .collapse-btn{transform:translateX(-50%) rotate(180deg);left:50%;margin-left:0}.sidebar.collapsed~.content-view-enrolled{width:100%;margin-left:0}.content-view-enrolled{width:calc(100% - 250px);padding:20px;background-color:var(--bg-color);display:flex;justify-content:center;align-items:center;border-left:2px solid #eee;transition:width .5s cubic-bezier(.25, .46, .45, .94),margin-left .5s cubic-bezier(.25, .46, .45, .94);overflow-x:hidden;overflow-y:auto;box-sizing:border-box;will-change:width,margin-left}.video-container{position:relative;max-width:100%;border-radius:10px;overflow:hidden;box-sizing:border-box}video{border-radius:10px;width:100%;max-width:100%;height:auto;box-shadow:0 5px 15px rgba(0,0,0,.1);object-fit:contain;box-sizing:border-box}img{max-width:100%;height:auto;box-sizing:border-box}#content-view{display:block;width:100%;max-width:100%;height:100%;position:relative;overflow-x:hidden;box-sizing:border-box}.player-container{border-radius:10px;max-width:700px;width:100%;margin:auto;position:relative;box-sizing:border-box}.player-container h1{margin-top:20px;margin-bottom:10px;color:var(--text-color);font-size:1.8rem;text-align:center}.player{border-radius:10px;width:100%;height:0;padding-bottom:56.25%;box-shadow:0 10px 0 -3px rgba(0,0,0,.2);position:relative;overflow:hidden;background:#000}@media (max-width:768px){.player-container{max-width:100%;margin:0}.player{border-radius:5px}}.pdf-container{max-width:100%;height:100%;overflow:auto;box-sizing:border-box}.like-dislike{display:flex;align-items:center;justify-content:flex-start;color:#fff}.like-dislike button{background:0 0;border:none;cursor:pointer;display:flex;align-items:center;padding:5px 10px;font-size:18px;color:#958d8d;transition:color .2s ease}.like-dislike button i{margin-right:5px}.likes-count{margin-right:20px;font-size:16px}.dislike-btn{margin-left:20px}.like-btn.active i,.like-btn:hover{color:#49f549}.dislike-btn.active i,.dislike-btn:hover{color:#e01616}.like-dislike button:focus{outline:0}.like-dislike button:disabled{cursor:not-allowed;color:silver}.comments-section{margin-top:20px;max-width:100%;overflow-x:hidden;box-sizing:border-box}.comments-list{margin-bottom:20px}.comment-text,.reply-text{margin-left:10px}.comment{border:1px solid #ccc;padding:10px;margin-bottom:10px;border-radius:8px;max-width:100%;overflow-wrap:break-word;word-wrap:break-word;box-sizing:border-box}.comment-form{margin-top:20px;background-color:var(--bg-color);padding:20px;border-radius:8px;box-shadow:0 4px 8px rgba(0,0,100,.6);max-width:100%;width:100%;box-sizing:border-box}.comment-form input,.comment-form textarea{width:100%;margin-bottom:15px;padding:10px;border:1px solid #ced4da;border-radius:5px;font-size:16px;min-height:15px;min-width:70px;resize:both;transition:border-color .3s ease;box-sizing:border-box}.comment-form input:focus,.comment-form textarea:focus{border-color:#007bff;outline:0}.comment-form button{padding:12px 20px;font-size:16px;color:#fff;background-color:#007bff;border:none;border-radius:5px;cursor:pointer;transition:background-color .3s ease}.comment-form button:hover{background-color:#0056b3;transform:translateY(-2px);box-shadow:0 4px 8px rgba(0,123,255,.3)}.videoInfo{margin-top:30px;padding:20px;background:var(--bg-color);border-radius:12px;max-width:700px;margin-left:auto;margin-right:auto}.videoInfo h2{color:var(--text-color);margin-top:20px;margin-bottom:15px;font-size:1.5rem}.videoInfo p{color:var(--text-color);line-height:1.6;margin-bottom:15px}.videoInfo hr{border:none;border-top:2px solid var(--border-color);margin:25px 0}iframe{border:none;box-shadow:0 5px 15px rgba(0,0,0,.1);max-width:100%;width:100%;box-sizing:border-box}.enroll-container{text-align:center;max-width:100%;padding:10px;box-sizing:border-box}.enroll-btn{padding:15px 50px;font-size:18px;background:linear-gradient(135deg,#28a745 0,#218838 100%);color:#fff;border:none;border-radius:8px;cursor:pointer;transition:background .3s ease}.enroll-btn:hover{background:linear-gradient(135deg,#218838 0,#28a745 100%);transform:translateY(-3px);box-shadow:0 5px 15px rgba(0,0,0,.2)}.fullscreen-pdf-toggle{position:absolute;top:10px;right:10px;width:40px;height:40px;background-color:#333;color:#fff;border:none;border-radius:50%;font-size:20px;cursor:pointer;z-index:1000;display:flex;align-items:center;justify-content:center;transition:background-color .3s ease,transform .3s ease;box-shadow:0 4px 8px rgba(0,0,0,.2)}.fullscreen-pdf-toggle:hover{background-color:#555;transform:scale(1.1)}.fullscreen-pdf-toggle:active{background-color:#111}.fullscreen-pdf-toggle:focus{outline:0}.comment-header,.reply-header{display:flex;align-items:center;margin-bottom:10px}.comment-pic,.reply-pic{margin-right:10px}.comment-header img,.reply-header img{width:40px;height:40px;border-radius:50%;object-fit:cover}.comment-info,.reply-info{display:flex;flex-direction:column}.comment-info p,.reply-info p{margin:0;padding:0;line-height:1.2}.comment-info .comment-date,.reply-info .reply-date{margin-top:2px;font-size:13px}.edit-textarea,.reply-textarea{width:100%;min-height:60px;font-size:1rem;padding:10px;border:1px solid #ccc;border-radius:5px;box-shadow:0 2px 4px rgba(0,0,0,.1);resize:vertical;transition:border .2s ease,box-shadow .2s ease}.edit-textarea:focus,.reply-textarea:focus{border-color:#007bff;box-shadow:0 0 6px rgba(0,123,255,.25);outline:0}button{font-size:.9rem;padding:6px 12px;border:none;border-radius:5px;cursor:pointer;transition:background-color .2s ease}.comment-interactions,.reply-interactions{display:flex;align-items:center;justify-content:space-between;margin-top:12px;gap:15px;flex-wrap:wrap}.comment-actions,.reply-actions{display:flex;align-items:center;gap:8px;flex-wrap:wrap}.delete-comment-btn,.delete-reply-btn,.edit-comment-btn,.edit-reply-btn,.reply-comment-btn,.report-comment-btn,.report-reply-btn{display:inline-flex;align-items:center;gap:4px;padding:6px 12px;font-size:.875rem;font-weight:500;border-radius:6px;border:1px solid transparent;background:0 0;cursor:pointer;color:var(--text-color);transition:all .2s ease-in-out}.reply-comment-btn{color:#007bff;border-color:#007bff}.reply-comment-btn:hover{background-color:#007bff;color:#fff}.edit-comment-btn,.edit-reply-btn{color:#28a745;border-color:#28a745}.edit-comment-btn:hover,.edit-reply-btn:hover{background-color:#28a745;color:#fff}.delete-comment-btn,.delete-reply-btn{color:#dc3545;border-color:#dc3545}.delete-comment-btn:hover,.delete-reply-btn:hover{background-color:#dc3545;color:#fff}.report-comment-btn,.report-reply-btn{color:#ff9800;border-color:#ff9800}.report-comment-btn:hover,.report-reply-btn:hover{background-color:#ff9800;color:#fff}.delete-comment-btn:focus,.delete-reply-btn:focus,.edit-comment-btn:focus,.edit-reply-btn:focus,.reply-comment-btn:focus,.report-comment-btn:focus,.report-reply-btn:focus{outline:2px solid currentColor;outline-offset:2px}.edit-btn,.post-reply-btn{background-color:#007bff;color:#fff}.edit-btn:hover,.post-reply-btn:hover{background-color:#0056b3}.save-edit-btn{background-color:#28a745;color:#fff}.save-edit-btn:hover{background-color:#218838}.cancel-edit-btn,.cancel-reply-btn{background-color:#dc3545;color:#fff;margin-left:5px}.cancel-edit-btn:hover,.cancel-reply-btn:hover{background-color:#c82333}.delete-btn{background-color:#6c757d;color:#fff;margin-left:5px}.delete-btn:hover{background-color:#5a6268}button+button{margin-left:10px}.swal2-success-circular-line-left,.swal2-success-circular-line-right,.swal2-success-fix{display:none}@keyframes shimmer{0%{background-position:-468px 0}100%{background-position:468px 0}}.skeleton{animation:shimmer 1.2s ease-in-out infinite;background:linear-gradient(to right,rgba(255,255,255,.05) 8%,rgba(255,255,255,.15) 18%,rgba(255,255,255,.05) 33%);background-size:800px 104px;display:inline-block;position:relative;overflow:hidden}.chapter-loading{text-align:center;padding:40px 20px}.chapter-loading .spinner{display:inline-block;width:40px;height:40px;border:4px solid rgba(0,123,255,.2);border-top-color:#007bff;border-radius:50%;animation:spin 1s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}@keyframes fadeInContent{from{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@media (max-width:1024px){.course-main-container{flex-direction:column}.sidebar{width:100%;min-width:unset;height:auto;border-radius:20px;padding:10px 20px;box-shadow:none;transition:height .4s cubic-bezier(.4, 0, .2, 1),padding .4s cubic-bezier(.4, 0, .2, 1),margin-bottom .4s cubic-bezier(.4, 0, .2, 1)}.sidebar h2{font-size:20px;margin-bottom:20px}.content-view-enrolled{width:100%;margin-top:20px}.header-content{flex-direction:column;text-align:center;gap:10px}.course-image-small{width:50%;max-width:150px}.sidebar.collapsed{height:0;min-height:0;width:0;min-width:0;padding:0;overflow:visible;margin-bottom:0}.sidebar.collapsed .sidebar-nav,.sidebar.collapsed h2,.sidebar.collapsed p{display:none;opacity:0;visibility:hidden}.sidebar.collapsed .collapse-btn{display:block;position:fixed;top:80px;left:50%;transform:translateX(-50%) rotate(90deg);margin:0;background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);border-radius:50%;width:50px;height:50px;z-index:1000;box-shadow:0 4px 8px rgba(0,0,0,.3)}.sidebar.collapsed~.content-view-enrolled{width:100%;margin-top:0}.collapse-btn{display:block}}@media (max-width:768px){body{padding-top:60px}main{padding:10px}.sidebar{width:100%;min-width:unset;padding:15px;margin-bottom:20px;box-shadow:none;border-radius:15px}.sidebar h2{font-size:18px;margin-bottom:15px;word-wrap:break-word}.sidebar-nav ul li a{font-size:16px;padding:8px 12px;word-wrap:break-word}.content-view-enrolled{width:100%;padding:10px}.header-content{flex-direction:column;padding:10px;font-size:1rem}.header-content h1{font-size:1rem;word-wrap:break-word;text-align:center}.course-image-small{width:80%;max-width:200px;margin-top:10px}.toggle-theme-btn{bottom:10px;right:10px}.fullscreen-pdf-toggle{top:5px;right:5px;width:35px;height:35px;font-size:18px}.enroll-btn{padding:12px 40px;font-size:16px;width:100%;max-width:300px}.like-dislike button{padding:8px 12px;font-size:20px}.comment-form button{padding:10px 16px;font-size:15px;width:100%;max-width:200px}.chapter-content{padding:20px 15px}.table-container{margin:20px -10px;border-radius:4px}.sidebar.collapsed{height:0;min-height:0;padding:0;margin-bottom:0;overflow:visible}.sidebar.collapsed .sidebar-nav,.sidebar.collapsed h2,.sidebar.collapsed p{display:none;opacity:0;visibility:hidden}.sidebar.collapsed .collapse-btn{display:flex;position:fixed;top:70px;right:20px;transform:none;margin:0;background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);border-radius:50%;width:50px;height:50px;z-index:1000;box-shadow:0 4px 8px rgba(0,0,0,.3);transition:all .3s ease}.sidebar.collapsed .collapse-btn:hover{background:linear-gradient(135deg,#7c1fd8 0,#3586ff 100%);box-shadow:0 6px 12px rgba(0,0,0,.4)}.sidebar.collapsed~.content-view-enrolled{width:100%;margin-top:0}}@media (max-width:480px){body{padding-top:56px}main{padding:8px}.header-content{font-size:.9rem;padding:8px}.header-content h1{font-size:.9rem}.course-image-small{width:90%;max-width:150px}.sidebar{padding:10px;border-radius:10px}.sidebar h2{font-size:16px;margin-bottom:10px}.sidebar-nav ul li a{font-size:14px;padding:6px 10px}.enroll-btn{padding:10px 30px;font-size:14px;width:100%;max-width:250px}.like-dislike button{font-size:18px;padding:6px 10px}.collapse-btn{font-size:22px;padding:10px}.sidebar.collapsed .collapse-btn{top:60px;right:15px;width:46px;height:46px;font-size:20px}.chapter-content{padding:15px 10px;font-size:1rem}.chapter-title{font-size:1.5rem;word-wrap:break-word}.section-header h1{font-size:1.4rem;padding:10px 0 10px 10px;word-wrap:break-word}.section-header h2{font-size:1.3rem;padding:8px 0 8px 10px;word-wrap:break-word}.subsection-header h3{font-size:1.2rem;padding:8px 0 6px 15px;word-wrap:break-word}.chapter-paragraph{font-size:.95rem;text-align:left}.chapter-table{font-size:.85rem;min-width:350px}.chapter-table td,.chapter-table th{padding:6px 8px}.comment-form input,.comment-form textarea{font-size:14px}.comment-interactions,.reply-interactions{flex-direction:column;align-items:flex-start;gap:10px}.comment-actions,.reply-actions{width:100%;justify-content:flex-start}.delete-comment-btn,.delete-reply-btn,.edit-comment-btn,.edit-reply-btn,.reply-comment-btn,.report-comment-btn,.report-reply-btn{font-size:.8rem;padding:5px 10px}}@media (max-width:360px){body{padding-top:52px}main{padding:5px}.header-content{font-size:.85rem;padding:5px}.header-content h1{font-size:.85rem}.course-image-small{width:100%;max-width:120px}.sidebar{padding:8px}.content-view-enrolled{padding:8px}.chapter-content{padding:10px 8px;font-size:.9rem}.chapter-title{font-size:1.3rem}.enroll-btn{font-size:13px;padding:8px 20px}}.chapter-container{width:100%;max-width:100%;background-color:var(--bg-color);border-radius:12px;overflow-y:visible;overflow-x:hidden;box-sizing:border-box}.chapter-header{background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);color:#fff;padding:30px;border-radius:12px 12px 0 0;box-shadow:0 4px 6px rgba(0,0,0,.1)}.chapter-title{font-size:2.5rem;font-weight:700;margin:0;text-shadow:2px 2px 4px rgba(0,0,0,.2)}.chapter-content{padding:40px;line-height:1.8;font-size:1.1rem;margin-bottom:0;max-width:100%;overflow-wrap:break-word;word-wrap:break-word;box-sizing:border-box}.chapter-text{max-width:900px;width:100%;margin:0 auto;box-sizing:border-box}.section-header{color:var(--title-bar-bg);font-size:1.8rem;font-weight:700;margin:40px 0 20px 0;padding-bottom:10px;border-bottom:3px solid var(--title-bar-bg);text-transform:uppercase;letter-spacing:1px}.section-header h1{color:var(--title-bar-bg);font-size:1.9rem;font-weight:700;margin:45px 0 25px 0;padding:15px 0 15px 20px;border-bottom:3px solid var(--title-bar-bg);text-transform:uppercase;letter-spacing:1.2px;background:linear-gradient(90deg,rgba(0,123,255,.05) 0,transparent 100%)}.section-header h2{color:var(--title-bar-bg);font-size:1.7rem;font-weight:700;margin:35px 0 20px 0;padding:12px 0 12px 15px;border-bottom:2px solid var(--title-bar-bg);text-transform:uppercase;letter-spacing:1px;background:linear-gradient(90deg,rgba(0,123,255,.03) 0,transparent 100%)}.subsection-header{color:var(--text-color);font-size:1.4rem;font-weight:600;margin:30px 0 15px 0;padding-left:15px;border-left:4px solid var(--title-bar-bg)}.subsection-header h3{color:var(--text-color);font-size:1.5rem;font-weight:600;margin:30px 0 15px 0;padding:10px 0 8px 25px;border-left:4px solid var(--title-bar-bg);background:linear-gradient(90deg,rgba(0,123,255,.02) 0,transparent 100%)}.subsection-header h4{color:var(--text-color);font-size:1.3rem;font-weight:600;margin:25px 0 12px 0;padding:8px 0 6px 35px;border-left:3px solid var(--title-bar-bg)}.subsection-header h5{color:var(--text-color);font-size:1.2rem;font-weight:600;margin:20px 0 10px 0;padding:6px 0 4px 45px;border-left:2px solid var(--title-bar-bg)}.subsection-header h6{color:var(--text-color);font-size:1.1rem;font-weight:600;margin:18px 0 8px 0;padding:4px 0 2px 55px;border-left:2px solid var(--title-bar-bg)}.chapter-paragraph{margin:15px 0;text-align:justify;color:var(--text-color);line-height:1.9;max-width:100%;overflow-wrap:break-word;word-wrap:break-word}.section-header+.chapter-paragraph,h1.section-header+.chapter-paragraph,h2.section-header+.chapter-paragraph{margin-left:20px}.subsection-header+.chapter-paragraph,h3.subsection-header+.chapter-paragraph,h4.subsection-header+.chapter-paragraph,h5.subsection-header+.chapter-paragraph,h6.subsection-header+.chapter-paragraph{margin-left:40px}.chapter-list{margin:20px 0 20px 20px;padding-left:40px;list-style-type:disc}.subsection-header+.chapter-list,h3.subsection-header+.chapter-list,h4.subsection-header+.chapter-list,h5.subsection-header+.chapter-list,h6.subsection-header+.chapter-list{margin-left:40px}.chapter-list li{margin:12px 0;color:var(--text-color);line-height:1.7}.chapter-list li::marker{color:var(--title-bar-bg);font-size:1.2em}[data-theme=dark] .chapter-header{background:linear-gradient(135deg,#1f1f1f 0,#0056b3 100%)}[data-theme=dark] .section-header,[data-theme=dark] h1.section-header,[data-theme=dark] h2.section-header{color:#4a9eff;border-bottom-color:#4a9eff;background:linear-gradient(90deg,rgba(74,158,255,.05) 0,transparent 100%)}[data-theme=dark] .subsection-header,[data-theme=dark] h3.subsection-header,[data-theme=dark] h4.subsection-header,[data-theme=dark] h5.subsection-header,[data-theme=dark] h6.subsection-header{border-left-color:#4a9eff;background:linear-gradient(90deg,rgba(74,158,255,.02) 0,transparent 100%)}[data-theme=dark] .chapter-list li::marker{color:#4a9eff}.table-container{overflow-x:auto;margin:25px 0;border-radius:8px;box-shadow:0 2px 8px rgba(0,0,0,.1);max-width:100%;-webkit-overflow-scrolling:touch}.chapter-table{width:100%;min-width:450px;border-collapse:collapse;background-color:var(--bg-color);font-size:1rem}.chapter-table td,.chapter-table th{padding:12px 15px;text-align:left;border:1px solid var(--border-color)}.chapter-table th{background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);color:#fff;font-weight:600;text-transform:uppercase;font-size:.95rem;letter-spacing:.5px}.chapter-table tr:nth-child(2n){background-color:rgba(0,0,0,.02)}.chapter-table tr:hover{background-color:rgba(0,123,255,.05);transition:background-color .3s ease}[data-theme=dark] .chapter-table{border-color:#444}[data-theme=dark] .chapter-table th{background:linear-gradient(135deg,#1f1f1f 0,#0056b3 100%)}[data-theme=dark] .chapter-table tr:nth-child(2n){background-color:rgba(255,255,255,.02)}[data-theme=dark] .chapter-table tr:hover{background-color:rgba(255,255,255,.05)}.katex{font-size:1.1em}.katex-display{margin:20px 0;padding:15px;background-color:rgba(0,0,0,.02);border-radius:8px;border-left:4px solid var(--title-bar-bg);overflow-x:auto;overflow-y:hidden}[data-theme=dark] .katex-display{background-color:rgba(255,255,255,.03)}.chapter-list li .katex,.chapter-paragraph .katex{margin:0 2px}.chapter-content code,.chapter-list li code,.chapter-paragraph code{background-color:rgba(0,0,0,.05);padding:2px 6px;border-radius:4px;font-family:"Courier New",monospace;font-size:.95em}[data-theme=dark] .chapter-content code,[data-theme=dark] .chapter-list li code,[data-theme=dark] .chapter-paragraph code{background-color:rgba(255,255,255,.1)}.code-block{background-color:rgba(0,0,0,.05);border-left:4px solid var(--title-bar-bg);border-radius:8px;padding:20px;margin:20px 0;overflow-x:auto;font-family:"Courier New",Monaco,monospace;font-size:.95em;line-height:1.6}.code-block code{background:0 0;padding:0;border-radius:0;color:var(--text-color)}[data-theme=dark] .code-block{background-color:rgba(255,255,255,.05)}.chapter-blockquote{border-left:4px solid var(--title-bar-bg);padding:15px 20px;margin:20px 0;background-color:rgba(0,0,0,.02);border-radius:4px;font-style:italic;color:var(--text-color)}[data-theme=dark] .chapter-blockquote{background-color:rgba(255,255,255,.03)}.chapter-hr{border:none;height:2px;background:linear-gradient(to right,transparent,var(--title-bar-bg),transparent);margin:30px 0}.chapter-list li strong,.chapter-paragraph strong,.section-header strong,.subsection-header strong{font-weight:700;color:var(--text-color)}.chapter-list li em,.chapter-paragraph em{font-style:italic;color:var(--text-color)}@media (max-width:768px){.chapter-content{padding:20px 15px;font-size:1rem}.chapter-title{font-size:1.8rem;word-wrap:break-word}.section-header{font-size:1.4rem;word-wrap:break-word}.subsection-header{font-size:1.2rem;word-wrap:break-word}.table-container{margin:20px -15px;overflow-x:auto;-webkit-overflow-scrolling:touch}.chapter-table{font-size:.9rem;min-width:400px}.chapter-table td,.chapter-table th{padding:8px 10px;word-wrap:break-word}.katex{font-size:1em}.katex-display{overflow-x:auto;-webkit-overflow-scrolling:touch;padding:10px}}@media (prefers-reduced-motion:reduce){*,::after,::before{animation-duration:0s!important;animation-iteration-count:1!important;transition-duration:0s!important;scroll-behavior:auto!important}.collapse-btn,.content-view-enrolled,.sidebar{will-change:auto}}a:focus-visible,button:focus-visible,input:focus-visible,textarea:focus-visible{outline:2px solid var(--title-bar-bg);outline-offset:2px}.sidebar-nav ul li a{text-shadow:0 1px 2px rgba(0,0,0,.3)}.chapter-loading .spinner{margin:0 auto}.settings-btn{position:fixed;top:80px;right:20px;width:50px;height:50px;border-radius:50%;background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);color:#fff;border:none;font-size:20px;cursor:pointer;z-index:999;box-shadow:0 4px 12px rgba(0,0,0,.3);transition:all .3s ease;display:flex;align-items:center;justify-content:center}.settings-btn:hover{transform:scale(1.1) rotate(90deg);box-shadow:0 6px 16px rgba(0,0,0,.4)}.settings-btn:active{transform:scale(.95)}.settings-modal{display:none;position:fixed;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,.7);backdrop-filter:blur(5px);z-index:1000;animation:fadeIn .3s ease}.settings-modal.show{display:flex;align-items:center;justify-content:center}@keyframes fadeIn{from{opacity:0}to{opacity:1}}.settings-content{background:var(--bg-color);border-radius:16px;max-width:500px;width:90%;max-height:80vh;overflow-y:auto;box-shadow:0 10px 40px rgba(0,0,0,.5);animation:slideIn .3s ease}@keyframes slideIn{from{transform:translateY(-50px);opacity:0}to{transform:translateY(0);opacity:1}}.settings-header{display:flex;justify-content:space-between;align-items:center;padding:20px 24px;border-bottom:2px solid var(--border-color);background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);color:#fff;border-radius:16px 16px 0 0}.settings-header h2{margin:0;font-size:1.5rem;display:flex;align-items:center;gap:10px}.close-modal{background:0 0;border:none;color:#fff;font-size:24px;cursor:pointer;padding:0;width:32px;height:32px;display:flex;align-items:center;justify-content:center;border-radius:50%;transition:background .3s ease}.close-modal:hover{background:rgba(255,255,255,.2)}.settings-body{padding:24px}.setting-item{display:flex;justify-content:space-between;align-items:center;padding:20px;margin-bottom:16px;border-radius:12px;background:var(--bg-color);border:2px solid var(--border-color);transition:all .3s ease}.setting-item:hover{border-color:#6a11cb;box-shadow:0 4px 12px rgba(106,17,203,.1)}.setting-item.danger{border-color:#dc3545}.setting-item.danger:hover{border-color:#c82333;box-shadow:0 4px 12px rgba(220,53,69,.2)}.setting-info{display:flex;align-items:flex-start;gap:16px;flex:1}.setting-icon{font-size:28px;color:#6a11cb;margin-top:4px}.setting-item.danger .setting-icon{color:#dc3545}.setting-info h3{margin:0 0 4px 0;font-size:1.1rem;color:var(--text-color)}.setting-info p{margin:0;font-size:.9rem;color:var(--text-color);opacity:.7}.setting-action-btn{padding:10px 20px;border:none;border-radius:8px;font-size:.95rem;font-weight:600;cursor:pointer;transition:all .3s ease;display:flex;align-items:center;gap:8px;white-space:nowrap}.save-progress-btn{background:linear-gradient(135deg,#28a745 0,#20c997 100%);color:#fff}.save-progress-btn:hover{background:linear-gradient(135deg,#218838 0,#1fa582 100%);transform:translateY(-2px);box-shadow:0 4px 8px rgba(40,167,69,.3)}.report-btn{background:linear-gradient(135deg,#ff9800 0,#ff6f00 100%);color:#fff}.report-btn:hover{background:linear-gradient(135deg,#e68900 0,#e65c00 100%);transform:translateY(-2px);box-shadow:0 4px 8px rgba(255,152,0,.3)}.drop-btn{background:linear-gradient(135deg,#dc3545 0,#c82333 100%);color:#fff}.drop-btn:hover{background:linear-gradient(135deg,#c82333 0,#bd2130 100%);transform:translateY(-2px);box-shadow:0 4px 8px rgba(220,53,69,.3)}.progress-container{background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);padding:16px 24px;border-radius:12px;margin-bottom:20px;box-shadow:0 4px 12px rgba(0,0,0,.15)}.progress-info{display:flex;justify-content:space-between;align-items:center;margin-bottom:12px}.progress-label{font-size:1rem;font-weight:600;color:#fff}.progress-percentage{font-size:1.2rem;font-weight:700;color:#fff}.progress-bar{width:100%;height:12px;background:rgba(255,255,255,.3);border-radius:6px;overflow:hidden}.progress-fill{height:100%;background:linear-gradient(90deg,#28a745 0,#20c997 100%);border-radius:6px;transition:width .5s ease;box-shadow:0 0 10px rgba(40,167,69,.5)}.material-check{margin-left:auto;width:24px;height:24px;border-radius:50%;background:0 0;border:2px solid rgba(255,255,255,.3);display:flex;align-items:center;justify-content:center;font-size:14px;color:transparent;transition:all .3s ease}.material-link.completed .material-check{background:#28a745;border-color:#28a745;color:#fff}.sidebar-header{margin:0;padding:0;line-height:1.2}.sidebar-header h2{margin:0;font-size:24px;font-weight:700;text-transform:uppercase}.welcome-message{text-align:center;padding:60px 20px}.welcome-icon{font-size:64px;color:#6a11cb;margin-bottom:20px}.welcome-message h3{font-size:1.8rem;color:var(--text-color);margin-bottom:12px}.welcome-message 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(--bg-color);border-radius:20px;padding:32px;box-shadow:0 10px 40px rgba(0,0,0,.1)}.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 16px;border-radius:20px;font-size:1rem;font-weight:600}.course-description-card{background:rgba(106,17,203,.05);padding:24px;border-radius:16px;margin-bottom:24px;border-left:4px solid #6a11cb}.course-description-card h2{font-size:1.4rem;color:var(--text-color);margin:0 0 12px 0;display:flex;align-items:center;gap:10px}.course-description-card p{font-size:1.05rem;line-height:1.7;color:var(--text-color);margin:0}.course-meta{display:grid;grid-template-columns:repeat(2,1fr);gap:16px;margin-bottom:32px}.meta-item{display:flex;align-items:center;gap:12px;padding:16px;background:var(--bg-color);border-radius:12px;border:2px solid var(--border-color);transition:all .3s ease}.meta-item:hover{border-color:#6a11cb;transform:translateY(-2px);box-shadow:0 4px 12px rgba(106,17,203,.1)}.meta-item i{font-size:24px;color:#6a11cb}.meta-item div{display:flex;flex-direction:column}.meta-label{font-size:.85rem;color:var(--text-color);opacity:.7;margin-bottom:2px}.meta-value{font-size:1.1rem;font-weight:600;color:var(--text-color)}.enroll-actions{display:flex;flex-direction:column;gap:12px}.enroll-actions form{margin:0}.enroll-btn-primary,.enroll-btn-secondary{width:100%;padding:16px 32px;border:none;border-radius:12px;font-size:1.1rem;font-weight:600;cursor:pointer;transition:all .3s ease;display:flex;align-items:center;justify-content:center;gap:10px}.enroll-btn-primary{background:linear-gradient(135deg,#28a745 0,#20c997 100%);color:#fff;box-shadow:0 4px 12px rgba(40,167,69,.3)}.enroll-btn-primary:hover{background:linear-gradient(135deg,#218838 0,#1fa582 100%);transform:translateY(-3px);box-shadow:0 6px 16px rgba(40,167,69,.4)}.enroll-btn-secondary{background:var(--bg-color);color:var(--text-color);border:2px solid #6a11cb}.enroll-btn-secondary:hover{background:linear-gradient(135deg,#6a11cb 0,#2575fc 100%);color:#fff;transform:translateY(-3px);box-shadow:0 6px 16px rgba(106,17,203,.3)}@media (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-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-content{background:#1f1f1f}[data-theme=dark] .setting-item{background:#2a2a2a;border-color:#444}[data-theme=dark] .course-info-card{background:#1f1f1f}[data-theme=dark] .meta-item{background:#2a2a2a;border-color:#444}[data-theme=dark] .course-description-card{background:rgba(106,17,203,.1)}