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console 命令行工具 X clear

                    
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console
<main class="wrapper1 clearfix">
    <section class="center">center</section>
    <section class="left">left</section>
    <section class="right">right</section>
</main>
.clearfix::after {
    display: block;
    clear: both;
    content: "";
}

section {
    float: left;
    width: 200px;
    font-weight: 700;
    text-align: center;
    text-transform: uppercase;
    line-height: 100px;
    color: #fff;
    background-color: #066;
}

.center {
    width: 100%;
    padding: 0 200px;
    background-color: #099;
    box-sizing: border-box;
}

.left {
    margin-left: -100%;
}

.right {
    margin-left: -200px;
}