换行时文字自动靠右显示是什么原因

html代码：

{
<!-- 导航栏 -->
    <div class="nav">
        <div class="logo">
            <img src="images/logo.png" alt="">
        </div>
        <div class="nav_text">
            <ul>
                <li>
                    <a href="#">首页</a>
                </li>
                <li>
                    <a href="#">学习路线</a>
                </li>
                <li>
                    <a href="#">知识库</a>
                </li>
                <li>
                    <a href="#">其他</a>
                </li>
                <li>
                    <a href="#">更多</a>
                </li>
                <li>
                    <a href="#">登录</a>
                </li>
            </ul>
        </div>
    </div>
    <!-- 主题部分 -->
    <div class="main_content">
        <div class="theme">
            <p class="l1">ALWAYS <br>BE A!</p>
            <p class="l3">小A智能创新团队</p>
            <p class="l4">LOOK FORWARD TO <br>YOU COMING</p>
        </div>
        <div class="pic">右边</div>
    </div>
}

css部分：

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
ul li {
    list-style: none;
}
a {
    text-decoration: none;
}
/* 版心 */
.w {
    width: 1200px;
    margin: auto;
}
/* 导航栏 */
.nav {
    background-color: #fff;
    height: 105px;
    border-bottom: 2px solid #ccc;
}
.nav img {
    float: left;
    display: block;
    width: 200px;
    height: 60px;
    margin:26px 88px 26px 278px ;
}
.nav_text ul li  {
    float: left;
    margin:36px 74px 36px 0;
}
.nav_text ul li a {
    
    display: inline-block;
    font-size: 22px;
    height: 67px;
    color: #737373;
}
.nav_text ul li:hover a {
    color: #0f9cf5;
    border-bottom: 5px solid #ffd155;
}

输出结果：

img

所以想问问ALWAYS BE A 为啥会靠右显示以及怎么解决这个问题。蟹蟹！

原因，没有清除浮动，加两br或者清除浮动，看代码

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
ul li {
    list-style: none;
}
a {
    text-decoration: none;
}
/* 版心 */
.w {
    width: 1200px;
    margin: auto;
}
/* 导航栏 */
.nav {
    background-color: #fff;
    height: 105px;
    border-bottom: 2px solid #ccc;
}
.nav img {
    float: left;
    display: block;
    width: 200px;
    height: 60px;
    margin:26px 88px 26px 278px ;
}
.nav_text ul li  {
    float: left;
    margin:36px 74px 36px 0;
}
.nav_text ul li a {
    display: inline-block;
    font-size: 22px;
    height: 67px;
    color: #737373;
}
.nav_text ul li:hover a {
    color: #0f9cf5;
    border-bottom: 5px solid #ffd155;
}
.clear{ clear:both} 
    </style>
</head>
<body>
    <div class="nav">
        <div class="logo">
            <img src="images/logo.png" alt="">
        </div>
        <div class="nav_text" >
            <ul>
                <li>
                    <a href="#">首页</a>
                </li>
                <li>
                    <a href="#">学习路线</a>
                </li>
                <li>
                    <a href="#">知识库</a>
                </li>
                <li>
                    <a href="#">其他</a>
                </li>
                <li>
                    <a href="#">更多</a>
                </li>
                <li>
                    <a href="#">登录</a>
                </li>
                
            </ul>
        </div>
    </div>
    <!-- <br>
    <br> -->


    
    <!-- 主题部分 -->
    <div class="main_content clear">
        <div class="theme">
            <p class="l1">ALWAYS <br>BE A!</p>
            <p class="l3">小A智能创新团队</p>
            <p class="l4">LOOK FORWARD TO <br>YOU COMING</p>
        </div>
        <div class="pic">右边</div>
    </div>

</body>
</html>