我是bootstrap的新手。我在改变小屏幕中列的顺序方面遇到了问题。它应该如下所示。有什么想法吗?
md& LG
[a] [b]
[c] [d]
sm& XS
[A]
[b]
[d]
[c]
我已尝试过推拉组合仅适用于' sm'但它改变了其他屏幕尺寸' md' &安培; ' LG' ..
.new_section {
text-align: center;
margin: 40px 0;
}
.about_bg {
background-color: rgba(252, 160, 0, 0.76);
}
.jumbo_text > h1 {
height: 200px;
line-height: 200px;
color: #FFFFFF;
}
.jumbo_text > p {
color: #666666;
padding: 20px 0;
overflow: hidden;
}
.arch_prof_bg {
background-color: rgba(252, 160, 0, 0.76);
}
.proj_heading_bg {
background-color: rgba(129, 86, 11, 0.8);
}
.proj_heading_bg > h1 {
margin: 20px;
color: #FFFFFF;
}

<section class="new_section">
<div class="container">
<div class="row" id="about">
<div class="col-md-6 jumbo_text about_bg">
<h1>Our Company</h1>
</div>
<div class="col-md-6 jumbo_text">
<P class="text-left">
It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout. The point of using Lorem Ipsum is that it has a more-or-less normal distribution of letters, as opposed to using 'Content here,
content here', making it look like readable English. Many desktop publishing packages and web page editors now use Lorem Ipsum as their default model text, and a search for 'lorem ipsum' will uncover many web sites still in their infancy. Various
versions have evolved over the years, sometimes by accident, sometimes on purpose (injected humour and the like).
</P>
</div>
</div>
<div class="row" id="arch_prof">
<div class="col-sm-6 col-sm-pull-6 jumbo_text">
<P class="text-left">
It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout. The point of using Lorem Ipsum is that it has a more-or-less normal distribution of letters, as opposed to using 'Content here,
content here', making it look like readable English. Many desktop publishing packages and web page editors now use Lorem Ipsum as their default model text, and a search for 'lorem ipsum' will uncover many web sites still in their infancy. Various
versions have evolved over the years, sometimes by accident, sometimes on purpose (injected humour and the like).
</P>
</div>
<div class="col-sm-6 col-sm-push-6 jumbo_text arch_prof_bg">
<h1>Architect Profile</h1>
</div>
</div>
</div>
</section>
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