body{margin:0;padding:0;box-sizing:border-box;font-family:Arial,sans-serif;line-height:1.6}h1,h2,h3,h4,h5,h6{margin:0;padding:0}a{text-decoration:none;color:inherit}ul{list-style-type:none;padding:0}button{cursor:pointer}.container{max-width:1200px;margin:0 auto;padding:20px}.header,.footer{background:#f8f9fa;padding:10px 0;text-align:center}.main-content{padding:20px}.main-layout{margin-top:20px;margin-left:10px;margin-right:10px}