style.css

body {
 background-color: #f5f5f5;
}

.container {
 max-width: 1200px;
 margin: 0 auto;
 padding: 20px;
}

.btn {
 margin: 20px 0;
}

.table {
 display: block;
 margin: auto;
}

.footer {
 display: flex;
 justify-content: center;
 align-items: center;
 height: 100px;
 background-color: #333;
 color: #fff;
 font-size: 18px;
 font-weight: bold;
}