:root{--bg: #f8fafc;--bg-gradient: linear-gradient(180deg, #ffffff 0%, #f1f5f9 100%);--fg: #0f172a;--card: rgba(255, 255, 255, .95);--card-hover: rgba(255, 255, 255, 1);--muted: #64748b;--accent: #6366f1;--accent-hover: #4f46e5;--accent-light: #e0e7ff;--accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);--border: #e2e8f0;--border-hover: #cbd5e1;--success: #10b981;--success-light: #d1fae5;--warning: #f59e0b;--warning-light: #fef3c7;--error: #ef4444;--error-light: #fecaca;--shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, .05);--shadow: 0 4px 12px -2px rgba(0, 0, 0, .08);--shadow-lg: 0 12px 24px -4px rgba(0, 0, 0, .12);--shadow-xl: 0 24px 48px -12px rgba(0, 0, 0, .18);--shadow-2xl: 0 32px 64px -12px rgba(0, 0, 0, .25);--blur: blur(12px);--nav-height: 68px;--border-radius: 12px;--border-radius-lg: 16px}[data-theme=dark]{--bg: #0a0e1a;--bg-gradient: linear-gradient(180deg, #0f172a 0%, #0a0e1a 100%);--fg: #f1f5f9;--card: rgba(30, 41, 59, .95);--card-hover: rgba(30, 41, 59, 1);--muted: #94a3b8;--accent: #818cf8;--accent-hover: #a5b4fc;--accent-light: #312e81;--accent-gradient: linear-gradient(135deg, #818cf8 0%, #a78bfa 100%);--border: #1e293b;--border-hover: #334155;--success: #34d399;--success-light: #064e3b;--warning: #fbbf24;--warning-light: #78350f;--error: #f87171;--error-light: #7f1d1d;--shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, .5);--shadow: 0 4px 12px -2px rgba(0, 0, 0, .4);--shadow-lg: 0 12px 24px -4px rgba(0, 0, 0, .5);--shadow-xl: 0 24px 48px -12px rgba(0, 0, 0, .6);--shadow-2xl: 0 32px 64px -12px rgba(0, 0, 0, .7)}html,body{padding:0;margin:0;background:var(--bg-gradient);color:var(--fg);font-family:-apple-system,BlinkMacSystemFont,Inter,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,sans-serif;transition:all .3s cubic-bezier(.4,0,.2,1);line-height:1.6;font-size:16px;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;scroll-behavior:smooth}*{box-sizing:border-box}a{color:var(--accent);text-decoration:none;transition:color .2s ease-in-out}a:hover{color:var(--accent-hover)}.container{max-width:1120px;margin:0 auto;padding:0 20px}.header{position:sticky;top:0;backdrop-filter:var(--blur);background:#ffffffd9;border-bottom:1px solid var(--border);box-shadow:var(--shadow);z-index:1000;transition:all .25s cubic-bezier(.4,0,.2,1);height:var(--nav-height)}[data-theme=dark] .header{background:#0a0e1ad9}.header:hover{box-shadow:var(--shadow-lg);border-bottom-color:var(--accent)}.header .inner{display:flex;align-items:center;justify-content:space-between;padding:20px;max-width:1200px;margin:0 auto}.brand{font-weight:800;font-size:1.8rem;letter-spacing:-.03em;background:var(--accent-gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;transition:all .25s ease-in-out;text-shadow:0 2px 12px rgba(99,102,241,.15)}.brand:hover{transform:scale(1.02) translateY(-1px);filter:brightness(1.1)}.nav{display:flex;align-items:center;gap:8px}.nav a{padding:10px 18px;font-size:14.5px;font-weight:600;color:var(--fg);border-radius:var(--border-radius);transition:all .2s cubic-bezier(.4,0,.2,1);position:relative}.nav a:hover{background:var(--accent-light);color:var(--accent);transform:translateY(-1px)}.nav a.active{background:var(--accent);color:#fff}.card{background:var(--card);border:1px solid var(--border);border-radius:16px;padding:32px;box-shadow:var(--shadow-sm);transition:all .3s cubic-bezier(.4,0,.2,1);position:relative;overflow:hidden}.card:before{content:"";position:absolute;top:0;left:0;right:0;height:1px;background:linear-gradient(90deg,transparent,var(--accent),transparent);opacity:0;transition:opacity .3s ease}.card:hover{box-shadow:var(--shadow-lg);transform:translateY(-4px);border-color:var(--border-hover);background:var(--card-hover)}.card:hover:before{opacity:1}.card.featured{border:2px solid var(--accent);box-shadow:var(--shadow-lg)}.card.featured:before{opacity:1;height:2px}.button{background:var(--accent-gradient);color:#fff;border:0;border-radius:var(--border-radius);padding:12px 24px;font-weight:600;font-size:14.5px;cursor:pointer;transition:all .25s cubic-bezier(.4,0,.2,1);display:inline-flex;align-items:center;justify-content:center;gap:8px;box-shadow:var(--shadow);position:relative;overflow:hidden}.button:before{content:"";position:absolute;top:0;left:-100%;width:100%;height:100%;background:linear-gradient(90deg,transparent,rgba(255,255,255,.2),transparent);transition:left .5s}.button:hover:before{left:100%}.button:hover{transform:translateY(-2px);box-shadow:var(--shadow-lg);filter:brightness(1.1)}.button:active{transform:translateY(0);box-shadow:var(--shadow)}.button.primary{background:var(--accent-gradient)}.button.success{background:linear-gradient(135deg,var(--success) 0%,#059669 100%);box-shadow:0 2px 4px #10b98133}.button.success:hover{box-shadow:0 8px 20px #10b9814d;transform:translateY(-2px)}.button.warning{background:linear-gradient(135deg,var(--warning) 0%,#d97706 100%);box-shadow:0 2px 4px #f59e0b33}.button.warning:hover{box-shadow:0 8px 20px #f59e0b4d;transform:translateY(-2px)}.button.ghost{background:transparent;border:2px solid var(--border);color:var(--fg);box-shadow:none}.button.ghost:hover{background:var(--accent);color:#fff;border-color:var(--accent);box-shadow:0 8px 20px #3b82f633}.button.large{padding:18px 36px;font-size:16px;border-radius:12px}.button.small{padding:8px 16px;font-size:14px;border-radius:8px}.grid{display:grid;gap:24px;grid-template-columns:repeat(auto-fit,minmax(300px,1fr))}.prose{line-height:1.6;color:var(--fg)}.muted{color:var(--muted)}.qchoice{text-align:left;width:100%;background:var(--card);border:2px solid var(--border);border-radius:12px;padding:20px;color:var(--fg);cursor:pointer;transition:all .3s cubic-bezier(.4,0,.2,1);margin-bottom:16px;position:relative;overflow:hidden;font-size:15px;line-height:1.5}.qchoice:before{content:"";position:absolute;left:0;top:0;bottom:0;width:4px;background:transparent;transition:background .3s ease}.qchoice:hover{border-color:var(--accent);box-shadow:var(--shadow-lg);transform:translateY(-2px)}.qchoice:hover:before{background:var(--accent)}.qchoice.sel{border-color:var(--accent);background:var(--accent-light);color:var(--accent);box-shadow:0 0 0 4px #3b82f61a;transform:translateY(-2px)}.qchoice.sel:before{background:var(--accent)}[data-theme=dark] .qchoice.sel{background:var(--accent);color:#fff}.qchoice.right{background:var(--success-light);border-color:var(--success);color:var(--success);box-shadow:0 0 0 4px #10b9811a}.qchoice.right:before{background:var(--success)}[data-theme=dark] .qchoice.right{background:var(--success);color:#fff}.qchoice.wrong{background:var(--error-light);border-color:var(--error);color:var(--error);box-shadow:0 0 0 4px #ef44441a}.qchoice.wrong:before{background:var(--error)}[data-theme=dark] .qchoice.wrong{background:var(--error);color:#fff}.qchoice:disabled{cursor:not-allowed;opacity:.6}.timer{position:fixed;top:80px;right:20px;z-index:1000;background:var(--card);border:1px solid var(--border);color:var(--fg);border-radius:8px;padding:8px 12px;font-family:ui-monospace,SFMono-Regular,SF Mono,Monaco,Cascadia Code,Roboto Mono,monospace;font-weight:600;font-size:14px;box-shadow:var(--shadow)}.progress{height:6px;background:var(--border);border-radius:6px;overflow:hidden}.progress>div{height:100%;background:var(--accent);transition:width .3s ease-in-out}img{max-width:100%;height:auto;border-radius:8px;box-shadow:var(--shadow)}summary{cursor:pointer;font-weight:600;color:var(--fg);padding:8px 0}@media (max-width: 1024px){.header .inner{padding:12px 20px}.navigation-menu{display:none!important}.mobile-nav-toggle{display:block!important}}@media (max-width: 768px){.container{padding:0 16px}.header .inner{padding:12px 16px;flex-wrap:wrap;gap:12px}.brand{font-size:1.5rem}.grid{grid-template-columns:1fr;gap:16px}.card{padding:20px}.timer{top:70px;right:10px;font-size:12px;padding:6px 10px}.button{padding:12px 20px;font-size:14px}.button.large{padding:16px 28px;font-size:15px}.qchoice{padding:16px;font-size:14px}}@media (max-width: 480px){.header .inner{padding:8px 12px}.brand{font-size:1.25rem}.card{padding:16px}.timer{top:60px;right:8px;font-size:11px;padding:4px 8px}.button{padding:10px 16px;font-size:13px}.qchoice{padding:12px;font-size:13px}}.certifications-section{margin-top:80px;margin-bottom:80px}.certifications-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:24px;margin-top:40px}.cert-card{background:var(--card);border:2px solid var(--border);border-radius:16px;padding:32px;text-decoration:none;color:var(--fg);transition:all .3s cubic-bezier(.4,0,.2,1);position:relative;overflow:hidden}.cert-card:before{content:"";position:absolute;top:0;left:0;right:0;height:3px;background:linear-gradient(90deg,var(--accent),var(--success),var(--warning));opacity:0;transition:opacity .3s ease}.cert-card:hover{transform:translateY(-8px);box-shadow:var(--shadow-xl);border-color:var(--accent)}.cert-card:hover:before{opacity:1}.cert-icon{width:72px;height:72px;margin-bottom:16px;display:inline-flex;align-items:center;justify-content:center}.cert-logo{width:100%;height:100%;padding:2px;object-fit:contain;display:block}.cert-card h3{margin:0 0 16px;font-size:1.25rem;font-weight:700;line-height:1.3}.cert-meta{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:20px}.cert-meta span{font-size:12px;padding:4px 8px;border-radius:6px;font-weight:600}.cert-difficulty{background:var(--accent-light);color:var(--accent)}.cert-difficulty.beginner{background:var(--success-light);color:var(--success)}.cert-difficulty.advanced{background:var(--warning-light);color:var(--warning)}.cert-duration,.cert-questions{background:var(--border);color:var(--muted)}.cert-cta{font-weight:600;color:var(--accent);font-size:14px;margin-top:8px}@keyframes slideInDown{0%{opacity:0;transform:translateY(-20px)}to{opacity:1;transform:translateY(0)}}@media (max-width: 768px){.certifications-grid{grid-template-columns:1fr;gap:16px}.cert-card{padding:24px}.cert-icon{width:64px;height:64px}.cert-logo{padding:2px}.nav-logo{width:100%;height:100%;object-fit:contain;padding:1px;display:block}.footer-logo{display:inline-block;width:18px;height:18px;object-fit:contain;vertical-align:middle}[data-theme=dark] img.aws-logo[data-dark-src=""]{mix-blend-mode:screen;filter:brightness(1.2) saturate(1.05) drop-shadow(0 0 1px rgba(255,255,255,.9)) drop-shadow(0 0 2px rgba(255,255,255,.5))}}@keyframes mobileMenuSlideIn{0%{opacity:0;transform:translate(-50%) translateY(-20px) scale(.95)}to{opacity:1;transform:translate(-50%) translateY(0) scale(1)}}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes slideInUp{0%{opacity:0;transform:translateY(20px)}to{opacity:1;transform:translateY(0)}}@keyframes slideInDown{0%{opacity:0;transform:translateY(-10px) translate(-50%)}to{opacity:1;transform:translateY(0) translate(-50%)}}@keyframes mobileMenuSlideIn{0%{opacity:0;transform:translate(-50%) translateY(-10px)}to{opacity:1;transform:translate(-50%) translateY(0)}}.nav-category-button:hover{background:var(--accent-gradient)!important;color:#fff!important;box-shadow:var(--shadow-lg)!important;transform:translateY(-2px)!important}.dropdown-menu:before{content:"";position:absolute;top:-6px;left:50%;transform:translate(-50%) rotate(45deg);width:12px;height:12px;background:var(--card);border:1px solid var(--border);border-bottom:none;border-right:none;z-index:-1}.dropdown-item:hover{background:var(--accent-light)!important;color:var(--accent)!important;transform:translate(4px)!important}.mobile-menu{animation:mobileMenuSlideIn .3s cubic-bezier(.4,0,.2,1)}.mobile-nav-toggle:hover{background:var(--accent-gradient)!important;color:#fff!important;box-shadow:0 8px 25px #2563eb4d!important;transform:translateY(-1px)!important}@media (max-width: 768px){.footer-content{grid-template-columns:1fr 1fr!important;gap:32px!important}}@media (max-width: 520px){.footer-content{grid-template-columns:1fr!important;gap:24px!important}}