好久没写什么大点的项目了，今天想着写一个个人博客好了。I did it！

做个人天地。肯定得有个主题色吧。整个下拉界面，先准备三个色系吧

        <el-header class="title">
            <el-dropdown @command="handleCommand">
                <span class="el-dropdown-link">
                主题色<el-icon class="el-icon--right"><arrow-down /></el-icon>
                </span>
                <template #dropdown>
                <el-dropdown-menu>
                    <el-dropdown-item command="day">白天</el-dropdown-item>
                    <el-dropdown-item command="night">黑夜</el-dropdown-item>
                    <el-dropdown-item command="primary">蓝天</el-dropdown-item>