#app{width:100%;height:100vh}:root{--main-color: #3eaf7c;--text-color: #2c3e50;--bg-color: #f5f5f5}body{margin:0;padding:0;font-family:Helvetica Neue,Helvetica,PingFang SC,Hiragino Sans GB,Microsoft YaHei,微软雅黑,Arial,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;color:var(--text-color);background-color:var(--bg-color)}*{box-sizing:border-box}.main-btn{background-color:var(--main-color);color:#fff;border:none;padding:10px 20px;border-radius:4px;cursor:pointer;font-size:16px;transition:opacity .3s}.main-btn:active{opacity:.8}