:root{--primary: #8e44ad;--primary-dark: #6c3483;--accent: #f39c12;--text-main: #2c3e50;--text-light: #7f8c8d;--bg-gradient: linear-gradient(135deg, #fdfbfd 0%, #ebdef0 100%);--card-shadow: 0 10px 30px rgba(142, 68, 173, .08);--hover-shadow: 0 15px 35px rgba(142, 68, 173, .15)}*{margin:0;padding:0;box-sizing:border-box;font-family:Poppins,sans-serif}body{background:var(--bg-gradient);color:var(--text-main);min-height:100vh;display:flex;flex-direction:column;overflow-x:hidden}header{background:#fffffff2;backdrop-filter:blur(10px);padding:1rem 5%;display:flex;justify-content:space-between;align-items:center;box-shadow:0 4px 20px #00000008;position:sticky;top:0;z-index:1000}.logo{font-size:1.6rem;font-weight:800;background:linear-gradient(45deg,var(--primary),#c0392b);background-clip:text;-webkit-background-clip:text;-webkit-text-fill-color:transparent;color:transparent;display:flex;align-items:center;gap:10px;text-decoration:none}.logo i{font-size:1.4rem;color:var(--primary);-webkit-text-fill-color:initial}nav ul{display:flex;gap:2.5rem;list-style:none;margin:0;padding:0}nav ul li a{font-weight:500;font-size:.95rem;color:var(--text-main);position:relative;padding-bottom:5px;text-decoration:none}nav ul li a:hover,nav ul li a.active{color:var(--primary)}nav ul li a:after{content:"";position:absolute;width:0;height:2px;bottom:0;left:0;background:var(--primary);transition:width .3s}nav ul li a:hover:after{width:100%}.mobile-menu-btn{display:none;font-size:1.5rem;cursor:pointer;color:var(--text-main)}.page-hero{padding:3rem 5% 1rem;text-align:center;max-width:900px;margin:0 auto;animation:fadeIn .8s ease-out}.breadcrumbs{font-size:.85rem;color:var(--text-light);margin-bottom:1.5rem;display:flex;justify-content:center;gap:8px;align-items:center}.breadcrumbs a{text-decoration:none;color:inherit;transition:.3s}.breadcrumbs a:hover{color:var(--primary)}.breadcrumbs span{color:var(--primary);font-weight:600}.page-hero h1{font-size:2.5rem;font-weight:700;color:var(--primary-dark);margin-bottom:.5rem}.page-hero p{font-size:1.1rem;color:var(--text-light);margin-bottom:2rem}.nav-buttons-container{display:flex;justify-content:space-between;max-width:1200px;margin:0 auto 2rem;padding:0 5%}.nav-btn{display:flex;align-items:center;gap:10px;padding:10px 24px;border-radius:50px;font-weight:600;font-size:.9rem;transition:all .3s ease;cursor:pointer;text-decoration:none}.nav-btn-back{background:#8e44ad1a;color:var(--primary)}.nav-btn-back:hover{background:#8e44ad33;transform:translate(-5px)}.chapters-container{padding:0 5% 4rem;max-width:1200px;margin:0 auto;display:grid;grid-template-columns:repeat(auto-fill,minmax(320px,1fr));gap:1.5rem}.chapter-card{background:#fff;border-radius:16px;padding:1.5rem;display:flex;flex-direction:column;box-shadow:0 4px 15px #0000000d;border:1px solid rgba(0,0,0,.05);transition:all .3s ease;position:relative;overflow:hidden;animation:fadeInUp .5s backwards;cursor:pointer}a.chapter-card{flex-direction:row;align-items:center;gap:1rem;text-decoration:none}.chapter-card:hover{transform:translateY(-5px);box-shadow:var(--hover-shadow);border-color:#8e44ad4d}.card-header{display:flex;align-items:center;gap:1rem;width:100%}.chap-number{font-size:2.5rem;font-weight:800;color:#8e44ad1a;line-height:1;flex-shrink:0;width:60px;text-align:center}.chapter-card:hover .chap-number{color:#8e44ad33}.chap-info{flex:1}.chap-info h3{font-size:1.1rem;font-weight:600;color:var(--text-main);margin-bottom:4px}.chap-info span{font-size:.8rem;color:var(--primary);font-weight:500;text-transform:uppercase;letter-spacing:1px}.arrow-icon{width:35px;height:35px;border-radius:50%;background:#f4ecf7;display:flex;justify-content:center;align-items:center;color:var(--primary);transition:all .3s}.chapter-card.active .arrow-icon{transform:rotate(180deg);background:var(--primary);color:#fff}a.chapter-card:hover .arrow-icon{background:var(--primary);color:#fff;transform:translate(5px)}.chapter-links{display:none;margin-top:1.5rem;padding-top:1rem;border-top:1px solid #eee;grid-template-columns:repeat(auto-fit,minmax(100px,1fr));gap:10px}.chapter-card.active .chapter-links{display:grid;animation:fadeIn .3s}.ex-link{padding:8px 12px;background:#f8f9fa;border-radius:8px;text-align:center;font-size:.85rem;color:var(--text-main);text-decoration:none;transition:.2s;border:1px solid #eee;display:flex;flex-direction:column;gap:5px}.ex-link:hover{background:var(--primary);color:#fff;border-color:var(--primary)}.ex-link i{font-size:1rem}.ws-link{padding:8px 12px;background:#f8f9fa;border-radius:8px;text-align:center;font-size:.85rem;color:var(--text-main);text-decoration:none;transition:.2s;border:1px solid #eee}.ws-link:hover{background:var(--primary);color:#fff;border-color:var(--primary)}.ws-link i{margin-right:5px}.floating-theme-btn{position:fixed;bottom:30px;left:30px;width:50px;height:50px;border-radius:50%;background:var(--text-main);color:#fff;border:none;box-shadow:0 4px 15px #0000004d;cursor:pointer;display:flex;align-items:center;justify-content:center;font-size:1.2rem;z-index:1000;transition:all .3s ease}.floating-theme-btn:hover{transform:translateY(-3px);box-shadow:0 6px 20px #0006}.back-to-top{position:fixed;bottom:30px;right:30px;width:50px;height:50px;border-radius:50%;background:var(--primary);color:#fff;border:none;box-shadow:0 4px 15px #0000004d;cursor:pointer;display:flex;align-items:center;justify-content:center;font-size:1.2rem;z-index:1000;opacity:0;visibility:hidden;transition:all .3s ease;transform:translateY(20px)}.back-to-top.show{opacity:1;visibility:visible;transform:translateY(0)}.back-to-top:hover{transform:translateY(-5px);box-shadow:0 6px 20px #8e44ad66}footer{background:#0f0f0f;color:#ecf0f1;padding:2rem 5%;text-align:center;margin-top:auto;border-top:4px solid var(--primary)}body.dark-mode{--text-main: #ecf0f1;--text-light: #bdc3c7;--bg-gradient: linear-gradient(135deg, #1a1a1a 0%, #2c3e50 100%)}body.dark-mode header{background:#141414f2}body.dark-mode .chapter-card{background:#2c2c2c;border-color:#444}body.dark-mode .ex-link,body.dark-mode .ws-link{background:#333;border-color:#444;color:#ecf0f1}body.dark-mode .nav-btn-back{background:#ffffff1a;color:#fff}body.dark-mode .floating-theme-btn{background:#fff;color:#2c3e50}@keyframes fadeInUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@media(max-width:768px){.chapters-container{grid-template-columns:1fr;padding:0 1rem 4rem}.chapter-card{padding:1.25rem}.chap-number{font-size:2rem;width:50px}.nav-buttons-container{padding:0 1rem}.mobile-menu-btn{display:block}nav ul{display:none;flex-direction:column;position:absolute;top:100%;left:0;width:100%;background:#fff;padding:1.5rem;box-shadow:0 10px 20px #0000001a;text-align:center}nav ul.active{display:flex}body.dark-mode nav ul{background:#2c2c2c}}