I want to get my first CSS layout reviewed.First of all, the related HTML code is as follows -<!DOCTYPE html><html lang=en>    <head>        <meta charset=utf-8 />        <title> Preferences </title>        <script src=options.js></script>        <link rel=stylesheet href=options.css />    </head>    <body>        <h1> Search in New Tab - Preferences </h1>        <form id=preference-form>                <label for=search-engine> Search Engine </label>                <select id=search-engine>                    <option id=google value=google selected=selected> Google </option>                    <option id=bing value=bing> Bing </option>                    <option id=yahoo value=yahoo> Yahoo! </option>                    <option id=duckduckgo value=duckduckgo> DuckDuckGo </option>                    <option id=wikipedia value=wikipedia> Wikipedia </option>                </select>                <br>                <label for=focus-search-tab> Make the search tab active </label>                <input type=checkbox value=focus-search-tab id=focus-search-tab />        </form>         </body></html>I wrote the following CSS file in order to provide satisfactory presentation to the HTML -h1{    width : 40%;    background : #eeeeee;    box-shadow : 0 0 5px 5px #888;    margin-top : 10%;    margin-left : 30%;    margin-right : 30%;    padding-top : 10px;    padding-bottom : 10px;    text-align : center;    font-family : Arial, Century Gothic, Lucida Sans Unicode;}form{    width : 30%;    background : #eeeeee;    box-shadow: 0 0 5px 5px #888;    margin-top : 1%;    margin-left : 35%;    margin-right : 35%;    padding-top : 10px;    padding-bottom : 10px;}label{    width : 60%;    display : inline-block;    text-align : right;    margin-top : 10px;    margin-bottom : 10px;    margin-right : 10px;        font-family : Arial;}The resulting HTML document looks like this:Basically, I wanted to avoid the use of float property. I felt that I could accomplish the same by using combinations of inline-block property, padding and margins. So, I used that. Was that the right way?Other than that, I would like to know if I did things right. Also, any improvements that make my CSS code better are welcome.
Review for CSS layout code
optimization;css;html5