.app{min-height:100vh;display:flex;flex-direction:column}.container{max-width:1200px;margin:0 auto;padding:0 var(--spacing-md);width:100%}.header{background:linear-gradient(135deg,var(--color-primary) 0%,var(--color-primary-dark) 100%);color:#fff;padding:var(--spacing-xl) 0;box-shadow:var(--shadow-md)}.site-title{font-size:2.5rem;font-weight:700;margin-bottom:var(--spacing-xs);letter-spacing:-.02em}.site-subtitle{font-size:1.125rem;opacity:.9;font-weight:300}.main{flex:1;padding:var(--spacing-xl) 0}.intro{text-align:center;margin-bottom:var(--spacing-xl);padding:var(--spacing-lg) 0}.intro-title{font-size:2rem;font-weight:600;margin-bottom:var(--spacing-md);color:var(--color-text)}.intro-text{font-size:1.125rem;color:var(--color-text-light);max-width:600px;margin:0 auto;line-height:1.8}.section-title{font-size:1.75rem;font-weight:600;margin-bottom:var(--spacing-lg);color:var(--color-text);text-align:center}.categories{margin-bottom:var(--spacing-xl)}.category-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:var(--spacing-lg);margin-top:var(--spacing-lg)}.category-card{background:var(--color-bg);border:2px solid var(--color-border);border-radius:var(--border-radius);padding:var(--spacing-lg);cursor:pointer;transition:var(--transition);position:relative;overflow:hidden}.category-card:before{content:"";position:absolute;top:0;left:0;right:0;height:4px;background:var(--category-color);transform:scaleX(0);transition:transform .3s ease}.category-card:hover{border-color:var(--category-color);box-shadow:var(--shadow-lg);transform:translateY(-2px)}.category-card:hover:before,.category-card.active:before{transform:scaleX(1)}.category-card.active{border-color:var(--category-color);box-shadow:var(--shadow-md);background:var(--color-bg-secondary)}.category-icon{font-size:3rem;margin-bottom:var(--spacing-md);display:block}.category-title{font-size:1.5rem;font-weight:600;margin-bottom:var(--spacing-sm);color:var(--color-text)}.category-description{color:var(--color-text-light);line-height:1.6;font-size:.95rem}.content-preview{margin-top:var(--spacing-xl);animation:fadeIn .3s ease}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.preview-card{background:var(--color-bg-secondary);border:1px solid var(--color-border);border-radius:var(--border-radius);padding:var(--spacing-lg);text-align:center}.preview-text{font-size:1.125rem;color:var(--color-text-light)}.footer{background:var(--color-bg-secondary);border-top:1px solid var(--color-border);padding:var(--spacing-lg) 0;margin-top:auto}.footer-text{text-align:center;color:var(--color-text-light);font-size:.9rem}@media (max-width: 768px){.site-title{font-size:2rem}.site-subtitle{font-size:1rem}.intro-title{font-size:1.5rem}.category-grid{grid-template-columns:1fr}.container{padding:0 var(--spacing-sm)}}*{margin:0;padding:0;box-sizing:border-box}:root{--color-primary: #2563eb;--color-primary-dark: #1e40af;--color-text: #1f2937;--color-text-light: #6b7280;--color-bg: #ffffff;--color-bg-secondary: #f9fafb;--color-border: #e5e7eb;--color-accent: #10b981;--spacing-xs: .5rem;--spacing-sm: 1rem;--spacing-md: 1.5rem;--spacing-lg: 2rem;--spacing-xl: 3rem;--border-radius: .5rem;--shadow-sm: 0 1px 2px 0 rgb(0 0 0 / .05);--shadow-md: 0 4px 6px -1px rgb(0 0 0 / .1);--shadow-lg: 0 10px 15px -3px rgb(0 0 0 / .1);--transition: all .2s ease-in-out}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;color:var(--color-text);background-color:var(--color-bg);line-height:1.6}code{font-family:Fira Code,Courier New,monospace}a{color:var(--color-primary);text-decoration:none;transition:var(--transition)}a:hover{color:var(--color-primary-dark);text-decoration:underline}