css float left布局换行不正常问题的解决

<div class="block">
        <div></div>
    </div>
    <div class="block">
        <div></div>
    </div>
    <div class="block">
        <div></div>
    </div>
    <div class="block" >
        <div id="special"></div>
    </div>
    <div class="block">
        <div></div>
    </div>
    <div class="block">
        <div></div>
    </div>

.block {

            width: 25%;
            paddg: 10px;
            float: left;
            box-sizg: border-box;

        }
        .block div {
            background-color: pk;
            width: 100%;
            height: 280px;
        }
        #special {
            height: 280px;
            background-color: green;
        }