:root{--primary-color: #3498db;--primary-color-hover: #2980b9;--secondary-color: #2c3e50;--accent-color: #e74c3c;--background-color: #f5f6fa;--text-color: #2c3e50;--light-gray: #ecf0f1;--dark-gray: #7f8c8d}*{margin:0;padding:0;box-sizing:border-box}html,body{height:100%}body{font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;background-color:var(--background-color);color:var(--text-color);line-height:1.6}.main-content{min-height:calc(100vh - 140px);padding-top:80px;padding-bottom:60px}.footer{background-color:var(--secondary-color);color:#fff;padding:1rem;text-align:center;position:fixed;bottom:0;width:100%}a{text-decoration:none;color:inherit}button{cursor:pointer;border:none;background-color:var(--primary-color);color:#fff;padding:.5rem 1rem;border-radius:4px;transition:background-color .3s ease}button:hover{background-color:var(--primary-color-hover)}.container{max-width:1200px;margin:0 auto;padding:0 1rem}.section{padding:4rem 0}.section-title{text-align:center;margin-bottom:2rem;color:var(--secondary-color);font-size:2.5rem}@media (max-width: 768px){.section{padding:2rem 0}.section-title{font-size:2rem}}