:root{--accent:#6c63ff;--accent-bg:#6c63ff1a;--border:#e2e8f0;--code-bg:#f8fafc;--text-h:#1a202c;--mono:"Fira Code", "Courier New", monospace;--shadow:0 2px 8px #00000014;--color-border-danger:#fc8181;--color-bg-danger:#fff5f5;--color-text-danger:#e53e3e}[data-theme=dark]{--accent:#7c73ff;--accent-bg:#7c73ff26;--border:#2d3748;--code-bg:#1a202c;--text-h:#f7fafc;--shadow:0 2px 8px #0000004d;--color-border-danger:#9b2c2c;--color-bg-danger:#2d1515;--color-text-danger:#fc8181}*{box-sizing:border-box;margin:0;padding:0}body{background-color:var(--code-bg);color:var(--text-h);font-family:Inter,system-ui,sans-serif;line-height:1.5;transition:background-color .3s,color .3s}[data-theme=dark] body{background-color:#0f1117}.sidebar-logo-link,.sidebar-logo-link:hover,.sidebar-logo-link:focus,.sidebar-logo-link:active,.sidebar-logo-link:visited{display:block;color:#0000!important;border:none!important;outline:none!important;text-decoration:none!important}.sidebar-logo-link{margin-bottom:50px;display:block;text-decoration:none!important}.sidebar-logo{align-items:center;gap:2px;font-size:24px;font-weight:800;display:flex;color:#fff!important}.sidebar-logo span{color:var(--accent)!important}.sidebar-logo-link:hover .sidebar-logo{opacity:.9;color:#fff!important}.terminal-container,.code-editor{border:1px solid var(--border);box-shadow:var(--shadow);background-color:#1a202c;border-radius:12px;padding:20px;transition:transform .3s,box-shadow .3s}.terminal-container:hover{border-color:var(--accent);transform:translateY(-4px);box-shadow:0 12px 20px #00000026}[data-theme=dark] .feature-card,[data-theme=dark] .auth-card{border:1px solid var(--border);background:#1a202c}[data-theme=dark] .auth-header h2{color:var(--text-h)}[data-theme=dark] .form-group input{color:var(--text-h);background:#2d3748;border-color:#4a5568}[data-theme=dark] .form-group label{color:#a0aec0}.feature-card,.auth-card,.course-card{background:var(--bg-card,#fff);border:1px solid var(--border);border-radius:12px;padding:20px;transition:all .3s}.navbar{background:var(--navbar-bg);-webkit-backdrop-filter:blur(10px);border-bottom:1px solid var(--border-color);z-index:1000;justify-content:space-between;align-items:center;width:100%;height:70px;padding:0 50px;transition:all .3s;display:flex;position:fixed;top:0;left:0}[data-theme=dark] .navbar{background:#1a202cd9;border-bottom:1px solid #ffffff1a}.navbar-container{justify-content:space-between;align-items:center;gap:24px;width:100%;max-width:1100px;height:64px;margin:0 auto;padding:0 24px;display:flex}.navbar-logo{flex-shrink:0;align-items:center;gap:10px;text-decoration:none;display:flex}.logo-icon{color:#fff;font-family:var(--mono);background:#6c63ff;border-radius:8px;padding:6px 10px;font-size:14px;font-weight:700}.logo-text{letter-spacing:-.3px;font-size:1.3rem;font-weight:700;color:var(--text-primary)!important}.logo-accent{color:gold}.navbar-links{flex:1;justify-content:center;gap:4px;list-style:none;display:flex}.navbar-links a{opacity:.85;border-radius:8px;padding:8px 16px;font-size:15px;font-weight:500;text-decoration:none;transition:all .2s;color:var(--text-primary)!important}.navbar-links a:hover{background:#6c63ff26;color:#6c63ff!important}.navbar-right{flex-shrink:0;align-items:center;gap:10px;display:flex}.theme-toggle{cursor:pointer;width:38px;height:38px;color:var(--text-primary);background:#6c63ff1a;border:none;border-radius:8px;justify-content:center;align-items:center;font-size:16px;transition:background .2s;display:flex}.btn-login{border:1.5px solid var(--border-color);border-radius:8px;padding:8px 16px;font-size:14px;font-weight:500;text-decoration:none;transition:all .2s;color:var(--text-primary)!important}.btn-register{background:#6c63ff;border-radius:8px;padding:8px 16px;font-size:14px;font-weight:600;text-decoration:none;transition:all .2s;color:#fff!important}.user-menu{align-items:center;gap:15px;display:flex}.welcome-msg{border-right:1px solid var(--border-color);padding-right:15px;font-size:14px;font-weight:500;color:var(--text-primary)!important}.btn-logout{color:#ff4f4f;cursor:pointer;background:#ff4f4f1a;border:1px solid #ff4f4f33;border-radius:8px;padding:6px 12px;font-weight:600;transition:all .3s}.btn-logout:hover{background:#ff4f4f;color:#fff!important}@media (width<=768px){.navbar{padding:0 20px}.navbar-links{background:var(--main-bg);border-bottom:1px solid var(--border-color);flex-direction:column;padding:16px;display:none;position:absolute;top:70px;left:0;right:0}.navbar-links.open{display:flex}}.auth-page{background:linear-gradient(135deg,#f0f4ff 0%,#e8f4fd 100%);justify-content:center;align-items:center;min-height:100vh;padding:40px 20px;display:flex}.auth-card{background:#fff;border:1px solid #6c63ff1a;border-radius:20px;width:100%;max-width:440px;padding:40px;box-shadow:0 8px 40px #6c63ff1f}.auth-header{text-align:center;margin-bottom:28px}.auth-logo{color:#fff;font-family:var(--mono);background:linear-gradient(135deg,#6c63ff,#4facfe);border-radius:12px;margin-bottom:16px;padding:10px 16px;font-size:18px;font-weight:700;display:inline-block}.auth-header h2{color:#1a202c;margin-bottom:6px;font-size:1.6rem}.auth-header p{color:#718096;opacity:1;margin:0;font-size:14px}.auth-alert{border-radius:10px;margin-bottom:20px;padding:12px 16px;font-size:14px}.auth-alert.error{color:#e53e3e;background:#fff5f5;border:1px solid #fc8181}.auth-alert.success{color:#276749;background:#f0fff4;border:1px solid #68d391}.auth-form{flex-direction:column;gap:18px;display:flex}.form-group{flex-direction:column;gap:6px;display:flex}.form-group label{color:#4a5568;font-size:14px;font-weight:500}.form-group input{color:#1a202c;background:#f8fafc;border:2px solid #e2e8f0;border-radius:10px;outline:none;padding:12px 16px;font-size:15px;transition:all .2s}.form-group input:focus{background:#fff;border-color:#6c63ff;box-shadow:0 0 0 4px #6c63ff1a}.auth-btn{color:#fff;cursor:pointer;background:linear-gradient(135deg,#6c63ff,#4facfe);border:none;border-radius:10px;margin-top:4px;padding:14px;font-size:16px;font-weight:600;transition:all .2s}.auth-btn:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 4px 15px #6c63ff59}.auth-btn:disabled{opacity:.6;cursor:not-allowed}.auth-switch{text-align:center;color:#718096;opacity:1;margin-top:20px;margin-bottom:0;font-size:14px}.auth-switch a{color:#6c63ff;font-weight:600;text-decoration:none}.auth-switch a:hover{text-decoration:underline}.home-page{background-color:#fff;padding-top:80px}[data-theme=dark] .home-page{background-color:#0f1117}.hero{justify-content:space-between;align-items:center;gap:40px;max-width:1100px;margin:0 auto;padding:100px 24px 80px;display:flex}.hero-content{flex:1;max-width:540px}.hero-badge{color:#6c63ff;background:#6c63ff1a;border:1px solid #6c63ff33;border-radius:20px;margin-bottom:20px;padding:6px 14px;font-size:14px;font-weight:600;display:inline-block}.hero-title{color:var(--text-h);margin-bottom:20px;font-size:3rem;font-weight:800;line-height:1.2}.hero-accent{background:linear-gradient(135deg,#6c63ff,#4facfe);-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text}.hero-subtitle{color:#718096;text-align:left;margin-bottom:32px;font-size:1.1rem;line-height:1.7}.hero-btns{flex-wrap:wrap;gap:12px;margin-bottom:40px;display:flex}.hero-btn-primary{background:linear-gradient(135deg,#6c63ff,#4facfe);border:none;border-radius:10px;padding:14px 28px;font-size:15px;font-weight:600;text-decoration:none;transition:all .2s;color:#fff!important}.hero-btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 25px #6c63ff59;color:#fff!important}.hero-btn-secondary{border:2px solid var(--border);background:0 0;border-radius:10px;padding:14px 28px;font-size:15px;font-weight:600;text-decoration:none;transition:all .2s;color:var(--text-h)!important}.hero-btn-secondary:hover{border-color:#6c63ff;color:#6c63ff!important}.hero-btn-primary:active,.hero-btn-secondary:active{background:inherit;outline:none}.hero-stats{align-items:center;gap:24px;display:flex}.stat{flex-direction:column;display:flex}.stat-num{color:var(--text-h);font-size:1.5rem;font-weight:700}.stat-label{color:#718096;font-size:13px}.stat-divider{background:var(--border);width:1px;height:36px}.hero-visual{flex:1;max-width:480px}.code-preview{background:#1a1f2e;border-radius:16px;overflow:hidden;box-shadow:0 20px 60px #0003}.code-preview-header{background:#252b3b;border-bottom:1px solid #ffffff0f;align-items:center;gap:6px;padding:14px 16px;display:flex}.dot{border-radius:50%;width:12px;height:12px}.dot.red{background:#ff5f57}.dot.yellow{background:#febc2e}.dot.green{background:#28c840}.code-preview-title{color:#ffffff80;font-size:13px;font-family:var(--mono);margin-left:8px}.code-preview-body{font-family:var(--mono);color:#a9b1d6;white-space:pre;margin:0;padding:24px;font-size:14px;line-height:1.8}.features{max-width:1100px;margin:0 auto;padding:80px 0}.features-grid{grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:24px;margin-top:40px;display:grid}.feature-card{border:1px solid var(--border);background:#fff;border-radius:16px;padding:28px;transition:all .2s;box-shadow:0 2px 8px #0000000a}[data-theme=dark] .feature-card{background:#1a202c}.feature-card:hover{border-color:#6c63ff4d;transform:translateY(-4px);box-shadow:0 12px 30px #6c63ff1f}@media (width<=768px){.hero{text-align:center;flex-direction:column;padding:60px 20px}.hero-title{font-size:2.2rem}.hero-subtitle{text-align:center}.hero-btns,.hero-stats{justify-content:center}.hero-visual{width:100%;margin-top:40px}}a{color:inherit!important;outline:none!important;text-decoration:none!important}a:-webkit-any-link{color:inherit!important;outline:none!important;text-decoration:none!important}.sidebar-logo-link,.sidebar-logo-link:hover,.sidebar-logo-link:active{color:#fff!important;text-decoration:none!important}.dashboard-wrapper{background-color:var(--code-bg);min-height:100vh;margin-top:70px;display:flex}.sidebar-container{z-index:100;border-right:1px solid #ffffff1a;flex-direction:column;width:260px;padding:30px 20px;display:flex;position:fixed;top:70px;bottom:0;left:0;background:#111c44!important}.sidebar-logo-link{border:none!important;outline:none!important;align-items:center!important;margin-bottom:40px!important;text-decoration:none!important;display:flex!important}.sidebar-logo{align-items:center;color:#fff!important;letter-spacing:-1px!important;font-family:Inter,sans-serif!important;font-size:24px!important;font-weight:800!important;text-decoration:none!important;display:flex!important}.sidebar-logo span{color:#6c63ff!important;margin-left:4px!important}.sidebar-menu{flex-direction:column;gap:8px;display:flex}.menu-item{border-radius:12px;align-items:center;gap:12px;padding:12px 16px;font-weight:500;transition:all .3s;display:flex;color:#a3aed0!important;text-decoration:none!important}.menu-item:hover,.menu-item.active{color:#fff!important;background:#ffffff1a!important}.menu-icon{font-size:18px}.main-content{background-color:var(--code-bg);flex:1;margin-left:260px;padding:40px}.top-banner,.info-card,.custom-course-card{padding:25px;background:var(--bg-card,#fff)!important;border:1px solid var(--border)!important;box-shadow:var(--shadow)!important;border-radius:16px!important}.custom-course-card:hover{transform:translateY(-5px);border-color:var(--accent)!important}.btn-start-now{text-align:center;border-radius:10px;margin-top:15px;padding:12px;font-weight:700;display:block;background:var(--accent)!important;color:#fff!important;text-decoration:none!important}.courses-page{background:var(--code-bg);min-height:100vh;padding-top:100px;padding-bottom:50px;transition:background .3s}.courses-container{max-width:1200px;margin:0 auto;padding:0 25px}.courses-header{text-align:center;margin-bottom:50px}.courses-header h1{color:var(--text-h);margin-bottom:10px;font-size:2.5rem}.courses-header p{color:var(--text-sub);font-size:1.1rem}.courses-grid{grid-template-columns:repeat(auto-fit,minmax(320px,1fr));gap:30px;display:grid}.course-card{background:var(--bg-card);border:1.5px solid var(--border);box-shadow:var(--shadow);border-radius:20px;flex-direction:column;padding:25px;transition:all .3s cubic-bezier(.4,0,.2,1);display:flex;position:relative;overflow:hidden}.course-card:hover{border-color:var(--accent);transform:translateY(-10px);box-shadow:0 15px 30px #6c63ff33}.course-content h3{margin-bottom:10px;font-size:20px;font-weight:700;color:var(--text-h)!important}.course-content p{flex:1;margin-bottom:25px;font-size:14px;line-height:1.6;color:var(--text-sub)!important}.course-badge{text-transform:uppercase;border-radius:10px;align-self:flex-start;margin-bottom:15px;padding:5px 14px;font-size:11px;font-weight:800;display:inline-block}.course-footer{border-top:1px solid var(--border);justify-content:space-between;align-items:center;margin-top:auto;padding-top:15px;display:flex}.course-footer span{color:var(--text-sub);font-size:13px}.start-btn{cursor:pointer;text-align:center;border:none;border-radius:10px;padding:10px 22px;font-size:14px;font-weight:600;text-decoration:none;transition:all .3s;background-color:var(--accent)!important;color:#fff!important}.course-badge.beginner{color:#38b2ac;background:#38b2ac1a}.course-badge.middle{color:#dd6b20;background:#dd6b201a}.course-badge.professional{color:#e53e3e;background:#e53e3e1a}[data-theme=dark] .course-card{background:#1a202c!important}@media (width<=768px){.courses-header h1{font-size:2rem}.courses-grid{grid-template-columns:1fr}}:root{--primary:#6c63ff;--bg-soft:#f4f7fe;--white:#fff;--text-dark:#1b2559;--text-gray:#a3aed0;--border-light:#e2e8f0;--success:#05cd99}.course-detail-page{background:var(--bg-soft);min-height:100vh;padding-top:100px}.detail-container{grid-template-columns:1fr 380px;gap:30px;max-width:1400px;margin:0 auto;padding:0 30px 40px;display:grid}.main-content-area{flex-direction:column;gap:25px;display:flex}.video-player-box{border:1px solid var(--border-light);background:#000;border-radius:24px;height:0;padding-bottom:56.25%;position:relative;overflow:hidden;box-shadow:0 15px 35px #0000001a}.video-player-box iframe{width:100%;height:100%;position:absolute;top:0;left:0}.course-info-card{background:var(--white);border:1px solid var(--border-light);text-align:center;border-radius:24px;padding:35px;box-shadow:0 4px 20px #00000008}.course-info-card h1{color:var(--text-dark);margin-bottom:12px;font-size:28px;font-weight:800}.course-info-card p{color:var(--text-gray);font-size:16px;line-height:1.7}.complete-lesson-btn{color:#fff;cursor:pointer;background:#27c93f;border:none;border-radius:14px;margin:25px auto 0;padding:15px 40px;font-weight:700;transition:all .3s;display:inline-block;box-shadow:0 8px 20px #27c93f33}.complete-lesson-btn:hover{transform:scale(1.05);box-shadow:0 10px 25px #27c93f4d}.sidebar-lessons{background:var(--white);border:1px solid var(--border-light);border-radius:24px;height:fit-content;padding:25px;position:sticky;top:100px;box-shadow:0 4px 20px #00000008}.sidebar-header{border-bottom:2px solid var(--bg-soft);margin-bottom:20px;padding-bottom:15px}.sidebar-header h3{color:var(--text-dark);font-weight:800}.lesson-card{cursor:pointer;border:1px solid #0000;border-radius:16px;align-items:center;gap:15px;margin-bottom:12px;padding:15px;transition:all .3s;display:flex}.lesson-card:hover{background:var(--bg-soft);border-color:var(--border-light)}.active-lesson{border-color:var(--primary);background:#6c63ff14}.active-lesson .lesson-index{background:var(--primary);color:#fff}.lesson-index{background:var(--bg-soft);width:34px;height:34px;color:var(--primary);border-radius:10px;justify-content:center;align-items:center;font-size:13px;font-weight:800;transition:all .3s;display:flex}.lesson-text h4{color:var(--text-dark);margin:0;font-size:15px;font-weight:600}.lesson-type{color:var(--text-gray);align-items:center;gap:5px;font-size:12px;display:flex}.return-link{text-align:center;color:var(--primary);margin-top:25px;font-size:14px;font-weight:700;text-decoration:none;display:block}.return-link:hover{text-decoration:underline}@media (width<=1100px){.detail-container{grid-template-columns:1fr;padding:0 20px 30px}.sidebar-lessons{position:static}}.editor-wrapper{color:#fff;background-color:#1a1a1a;flex-direction:column;height:calc(100vh - 70px);display:flex}.editor-header{background-color:#252526;border-bottom:1px solid #333;justify-content:space-between;align-items:center;padding:10px 25px;display:flex}.lang-badge{color:#000;background:#f7df1e;border-radius:4px;margin-right:10px;padding:2px 8px;font-size:12px;font-weight:700}.editor-header h3{color:#ccc;font-size:16px;display:inline}.run-button{color:#fff;cursor:pointer;background-color:#4caf50;border:none;border-radius:6px;padding:8px 20px;font-weight:600;transition:all .2s}.run-button:hover{background-color:#43a047;transform:scale(1.05)}.editor-main-content{flex:1;display:flex;overflow:hidden}.code-area{background-color:#1e1e1e;flex:1;position:relative}.code-area textarea{color:#d4d4d4;resize:none;background:0 0;border:none;outline:none;width:100%;height:100%;padding:20px;font-family:Fira Code,Courier New,monospace;font-size:16px;line-height:1.5}.output-area{background-color:#111;border-left:1px solid #333;flex-direction:column;width:350px;display:flex}.output-label{justify-content:space-between;align-items:center;display:flex;padding:8px 15px!important}.clear-btn{color:#888;cursor:pointer;background:0 0;border:1px solid #444;border-radius:4px;padding:2px 8px;font-size:10px}.clear-btn:hover{color:#fff;border-color:#666}.console-box{color:#0f0;white-space:pre-wrap;flex:1;margin:0;padding:20px;font-family:Courier New,monospace;font-size:14px;overflow-y:auto}::-webkit-scrollbar{width:8px}::-webkit-scrollbar-thumb{background:#333;border-radius:10px}.leaderboard-wrapper{background-color:#f4f7fe;min-height:100vh;margin-left:260px;padding:100px 40px 40px}.leaderboard-container{max-width:900px;margin:0 auto}.leaderboard-header{margin-bottom:30px}.leaderboard-header h1{color:#1b2559;margin:0;font-size:32px;font-weight:800}.leaderboard-header p{color:#a3aed0;margin-top:10px}.leaderboard-card{background:#fff;border:1px solid #edf2f7;border-radius:25px;padding:20px;box-shadow:0 4px 25px #0000000d}.leaderboard-table-header{color:#a3aed0;border-bottom:1px solid #f4f7fe;grid-template-columns:.5fr 2fr 1fr 1fr;padding:15px 25px;font-size:14px;font-weight:600;display:grid}.leaderboard-row{border-radius:15px;grid-template-columns:.5fr 2fr 1fr 1fr;align-items:center;margin-top:8px;padding:18px 25px;transition:all .3s;display:grid}.leaderboard-row:hover{background-color:#f8faff;transform:scale(1.01)}.active-user-row{background-color:#6c63ff14;border:1px solid #6c63ff33}.user-profile{align-items:center;gap:15px;display:flex}.user-avatar-small{color:#fff;background:linear-gradient(135deg,#6c63ff,#8e84ff);border-radius:10px;justify-content:center;align-items:center;width:35px;height:35px;font-size:14px;font-weight:700;display:flex}.user-name-text{color:#1b2559;font-weight:700}.user-level-badge{color:#718096;font-size:14px;font-weight:500}.user-xp-total{color:#6c63ff;font-weight:800}.rank{color:#1b2559;font-size:16px;font-weight:800}:root{--navbar-bg:#ffffffd9;--nav-text:#1a202c;--nav-border:#0000001a}[data-theme=dark]{--navbar-bg:#1a202cd9;--nav-text:#fff;--nav-border:#ffffff1a}.container{flex-direction:column;align-items:stretch;max-width:900px;min-height:100vh;margin:0 auto;padding:40px 20px;display:flex}h1{color:var(--text-h);text-align:center;margin-bottom:.5rem;font-size:2.5rem}p{text-align:center;opacity:.8;margin-bottom:2rem}.editor-section{flex-direction:column;gap:15px;width:100%;display:flex}textarea{width:100%;height:300px;font-family:var(--mono);border:2px solid var(--border);background-color:var(--code-bg);color:var(--text-h);border-radius:12px;outline:none;padding:20px;font-size:16px;transition:all .3s;box-shadow:inset 0 2px 4px #0000000d}textarea:focus{border-color:var(--accent);box-shadow:0 0 0 4px var(--accent-bg)}textarea:disabled{opacity:.6;cursor:not-allowed}.run-btn{background-color:var(--accent);color:#fff;cursor:pointer;border:none;border-radius:8px;align-self:center;padding:15px 30px;font-size:16px;font-weight:600;transition:transform .2s,background .2s}.run-btn:hover:not(:disabled){filter:brightness(1.1);transform:translateY(-2px)}.run-btn:active:not(:disabled){transform:translateY(0)}.run-btn:disabled{opacity:.6;cursor:not-allowed}.output-box{background:var(--code-bg);border:1px solid var(--border);box-shadow:var(--shadow);border-radius:12px;margin-top:30px;padding:20px}.output-box strong{color:var(--accent);margin-bottom:10px;display:block}pre{font-family:var(--mono);color:var(--text-h);white-space:pre-wrap;word-break:break-all;margin:0}.output-error{border-color:var(--color-border-danger);background:var(--color-bg-danger)}.output-error strong{color:var(--color-text-danger)!important}