.external-btn {
    font: 400 14px system-ui;
    padding: 6px 12px;
    background: #007bff;
    border: 1px solid #007bff;
    border-radius: 4px;
    color: white;
    text-decoration: none;
    display: inline-block;
    cursor: pointer;
    vertical-align: middle;
}

/* 确保input和a标签样式一致 */
input.external-btn, a.external-btn {
    box-sizing: border-box;
    line-height: normal;
    font-family: inherit;
}

/* 让按钮在hover时有反馈 */
.external-btn:hover {
    background: #0056b3;
    border-color: #0056b3;
}
a{TEXT-DECORATION:none}//去掉超链接的下划线
a:hover{TEXT-DECORATION:underline}//当鼠标移上去时出现下划线