html的问题

不知道为什么中间多了一白条，解决不了，希望大佬帮忙。
代码如下
<!DOCTYPE html>
<html>

👊🌦🍒☣🦮‎

<head>
<style>
#header {
    background-color:black;
    color:white;

🙌⛪🍼🅰🦠‌

    text-align:center;
   
}
#nav {
    line-height:30px;🧒‏🧢⌨😘👃
    background-color:#eeeeee;
    height:300px;
    width:100px;
    float:left;
    padding:5px;              
👍🚠🥣☪🐠‎}
#section {
    width:350px;
    float:left;
    padding:10px;                  
🤳🗺🍟™🦮‏}
#footer {
    background-color:black;
    color:white;
    clear:both;
💪⛴🥩↔🐙‏    text-align:center;
   padding:5px;                  
}
</style>
</head>
💪🗺🍓☣🦉‌
<body>

<div id="header">
<h1>City Gallery</h1>👴‍👠⌨😚✍
</div>

<div id="nav">
London<br>
Paris<br>
🧠🌡🍌↔🦬‎Tokyo<br>
</div>

<div id="section">
<h2>London</h2>🧒‏🕶✒🙄👂
<p>
London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.
</p>
<p>
🧠🧳🍊❌🦚‏Standing on the River Thames, London has been a major settlement for two millennia,
its history going back to its founding by the Romans, who named it Londinium.
</p>
</div>

👌🌧🥄🆎🦉‍<div id="footer">
Copyright ? W3Schools.com
</div>

</body>
🖕🦼🥩⁉🦜‎</html>