This is my very first attempt to write HTML and CSS. I designed this website for a friend. I'm not sure if I used the best practices or maybe I did something wrong but I just started my learning process so I would love a review to point bad practices and things I could have done better or I did wrong.This is meant to be the first section (above the fold) of a vertical single-page website.* {  font-family: Open Sans;  margin: 0px}#PageHeader {  background-color: rgb(236, 100, 62);  height: 615px;}/* logo and nav look aligned on the original file :c */#logo {  position: relative;  margin-left: 40px;  top: 30px;}a.nav:link {  text-decoration: none;  font-size: 12px;  font-weight: bold;  color: white;  text-transform: uppercase;  margin-right: 40px;  float: right;}a.nav:hover{  border-width: 0px 0px 3px 0px;  border-style: solid;}#heading{  color: white;  text-align: center;  line-height: 1.2;  margin-top: 150px;}h1{  font-size: 60px;  margin-bottom: 30px;}<html lang=pt-br>  <head>    <title>Empreendi na Rede</title>    <meta charset=utf-8>    <meta name=author content=Luciano Infanti>    <link href=https://fonts.googleapis.com/css?family=Open+Sans:400,400i,800 rel=stylesheet>  </head>  <body>    <header id=PageHeader>      <div id=logo>        <img src=https://s31.postimg.org/4esz43xaj/empreendipngwhite.png height=35>       <nav>        <a class=nav href=#>Solucoes</a>        <a class=nav href=#>Metodologia</a>        <a class=nav  href=#>Sobre nos</a>        <a class=nav  href=#>Depoimentos</a>        <a class=nav  href=#>Clientes</a>        <a class=nav  href=#>Contato</a>      </nav>      <div id=heading>        <h1>A consultoria empresarial<br> acaba de ser redefinida</h1>        <p id=kicker>Aliquam et placerat lacus. Donec pharetra nibh a placerat tincidunt.<br>  Integer viverra nisl dolor, in viverra enim sollicitudin nec.</p>      </div>    </header>  </body></html>
Upper section of a vertical single-page website
beginner;html;css;html5