您可以使用transform:translateX來實現這一點 header { font-family: Arial;}header nav{ color:white;}header nav ul{ list-style:none; margin:0; padding:0;}header nav ul li{ margin:0; padding: 0; float: left; width:200px; height:40px; background-color: rgb(187,199,124); line-height: 40px; text-align: center;}header nav ul li a{ display: block; text-decoration: none; color:white;}header nav ul li a:hover{ background-color: rgb(163,175,75); opacity: 0.5;}header nav ul li ul li{ display: none;}header nav ul li:hover ul li{ display: block;}.fit-picture{ max-width: 12%;}#rectangle{ width:1000px; height:900px; backg