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HTML 

              
                <!--
Artigo : Contraste de cores
Autor : Orivelton Cesar - www.orivelton.com.br
-->
<!DOCTYPE html>
<html lang="pt-BR">
  <head>
    <meta charset="utf-8">
    <title>Contraste de cores</title>
    <link rel="stylesheet" href="css/style.css">
  </head>
  <body>
    <div class="row row-header">
      <div class="container">
        <nav>
          <ul>
            <li>
              <a href="#content" title="Ir para o Conteúdo">Ir para o Conteúdo</a>
            </li>
            <li>
              <a href="#" title="Ir para o Topo">Ir para o Topo</a>
            </li>
            <li>
              <a href="#footer" title="Ir para o Rodapé">Ir para o Rodapé</a>
            </li>
            <li>
              <a href="#" data-contraste="0" title="Sem Contraste">Sem Contraste</a>
            </li>
            <li>
              <a href="#" data-contraste="1" title="Contraste Branco">Contraste Branco</a>
            </li>
            <li>
              <a href="#" data-contraste="2" title="Contraste Preto">Contraste Preto</a>
            </li>
            <li>
              <a href="#" data-contraste="3" title="Contraste Azul">Contraste Azul</a>
            </li>
          </ul>
        </nav>
      </div>
      <!-- End - .container-->
    </div>
    <!--  End - .row-->
    <div class="row row-top">
      <div class="container">
        <strong>Front End Developer</strong>
      </div>
    </div>
    <div class="row row-banner">
      <div class="container">
        <h1>Hi my names is <span>Orivelton</span></h1>
        <img src="https://i.imgur.com/fmY5HzM.png" alt="Avatar Orivelton" class="avatar">
        <img src="https://i.imgur.com/3RTGwHr.png" alt="" class="oculos">
      </div>
    </div>
    <div class="row row-content">
      <article class="container" id="content">
        <div class="box">
          <h2>Html5</h2>
          <i>★★★★★</i>
          <p>
            Mussum Ipsum, cacilds vidis litro abertis. Manduma pindureta quium dia nois paga.
            Nec orci ornare consequat. Praesent lacinia ultrices consectetur. Sed non ipsum felis.
            Si num tem leite então bota uma pinga aí cumpadi! Atirei o pau no gatis, per gatis num morreus.
            </p>
        </div>
        <div class="box">
          <h2>Css3</h2>
          <i>★★★★★</i>
          <p>
            Mussum Ipsum, cacilds vidis litro abertis. Manduma pindureta quium dia nois paga.
            Nec orci ornare consequat. Praesent lacinia ultrices consectetur. Sed non ipsum felis.
            Si num tem leite então bota uma pinga aí cumpadi! Atirei o pau no gatis, per gatis num morreus.
            </p>
        </div>
        <div class="box">
          <h2>Javascript</h2>
          <i>★★★★</i>
          <p>
            Mussum Ipsum, cacilds vidis litro abertis. Manduma pindureta quium dia nois paga.
            Nec orci ornare consequat. Praesent lacinia ultrices consectetur. Sed non ipsum felis.
            Si num tem leite então bota uma pinga aí cumpadi! Atirei o pau no gatis, per gatis num morreus.
            </p>
        </div>
        <div class="box">
          <h2>Typescript</h2>
          <i>★★★★</i>
          <p>
            Mussum Ipsum, cacilds vidis litro abertis. Manduma pindureta quium dia nois paga.
            Nec orci ornare consequat. Praesent lacinia ultrices consectetur. Sed non ipsum felis.
            Si num tem leite então bota uma pinga aí cumpadi! Atirei o pau no gatis, per gatis num morreus.
            </p>
        </div>
      </article>
    </div>
    <footer id="footer">
        Copyright (c) 2016 Copyright Holder All Rights Reserved.
    </footer>
    <script type="text/javascript" src="js/contraste.js"></script>
  </body>
</html>
!

CSS 

              
                /*
Artigo : Contraste de cores
Autor : Orivelton Cesar - www.orivelton.com.br
*/
* {margin: 0; padding: 0} img {border : 0}
body {
   font-family: Arial, 'Helvetica Neue', Helvetica, sans-serif;
}
/*START - Barra de Acessibilidade*/
.row {
  width: 100%;
  overflow: hidden;
}

.container {
  width: 1024px;
  margin: auto;
  overflow: hidden;
  display: block;
}

.row-header {
  background: #282e3a;
  position: fixed;
  z-index: 1;
  top: 0;
}

nav ul li {
  float: left;
  list-style: none;
}

nav ul li a {
  color: #FFFFFF;
  display: inline-block;
  padding: 17px;
  font-size: 11px;
  text-transform: uppercase;
}

nav ul li a[data-contraste="0"] {
  background: #FFFFFF;
  color: #000000;
}

.row-top {
  background: #64c4e8;
  color: #FFFFFF;
  margin-top: 47px;
}

.row-top .container {
  padding: 1.5% 0;
  text-align: center;
  font-size: 1.5em;
}

.row-banner, footer {
  background: #56c0e6;
  color: #FFFFFF;
  text-align: center;
}

.row-banner .container {
  padding: 8% 0;
  position: relative;
  text-align: center;
}

.row-banner .avatar {
  border: 5px solid #fff;
  border-radius: 50%;
  padding: 0.5%;
  margin-top: 2%;
}

.oculos {
  position: absolute;
  top: 49%;
  left: 40.7%;
}

.row-banner h1 {
  text-transform: uppercase;
}

.row-banner h1 span {
  color: #fdf210;
}

.row-content {
  background: #282e3a;
  color: #fdf210;
}

.row-content .container {
  padding: 8% 0;
}

.row-content .box {
  width: 46%;
  margin: 4% 0;
  float: left;
  text-align: center;
}

.row-content .box h2 {
  padding-bottom: 2%;
  text-transform: uppercase;
  letter-spacing: 10px;
}

.row-content .box i {
  font-style: normal;
  color: #fdf210;
  font: 1em;
}

.row-content .box p {
  color: #FFFFFF;
  padding: 2%;
}

footer {
  padding: 3% 0;
}

/*START - Contraste Branco*/

#contrasteBranco .row-header,
#contrasteBranco .row-top,
#contrasteBranco .row-banner,
#contrasteBranco .row-content,
#contrasteBranco footer{
  border-top: 1px solid #0a0a0a;
  background: #FFFFFF;
}

#contrasteBranco nav ul li a,
#contrasteBranco .row-top,
#contrasteBranco .row-banner,
#contrasteBranco .row-content,
#contrasteBranco .row-content .box p,
#contrasteBranco .row-content .box i,
#contrasteBranco .row-banner h1 span,
#contrasteBranco footer {
  color: #000000;
}

#contrasteBranco nav ul li a.contraste-active {
  color: #FFFFFF;
  background: #000000;
}

#contrasteBranco nav ul li a[data-contraste="1"],
#contrastePreto nav ul li a[data-contraste="0"] {
  background: #000000;
  color: #FFFFFF;
}

#contrasteBranco .row-banner .avatar {
  border: 5px solid #000;
}
/*END - Contraste Branco*/
/*START - Contraste Preto*/
#contrastePreto .row-header,
#contrastePreto .row-top,
#contrastePreto .row-banner,
#contrastePreto .row-content,
#contrastePreto footer{
  border-top: 1px solid #FFFFFF;
  background: #000000;
}

#contrastePreto nav ul li a,
#contrastePreto .row-top,
#contrastePreto .row-banner,
#contrastePreto .row-content,
#contrastePreto .row-content .box p,
#contrastePreto .row-content .box i,
#contrastePreto .row-banner h1 span,
#contrastePreto footer {
  color: #FFFFFF;
}

#contrastePreto nav ul li a[data-contraste="2"] {
  color: #000000;
  background: #FFFFFF;
}

#contrastePreto .row-banner .avatar {
  border: 5px solid #FFFFFF;
}
/*END - Contraste Preto*/
/*START - Contraste azul*/
#contrasteAzul .row-header,
#contrasteAzul .row-top,
#contrasteAzul .row-banner,
#contrasteAzul .row-content,
#contrasteAzul footer{
  border-top: 1px solid #FFFFFF;
  background: #0b325c;
}

#contrasteAzul nav ul li a[data-contraste="0"] {
  background: #0b325c;
}

#contrasteAzul nav ul li a[data-contraste="3"] {
  background: #FFFFFF;
  color: #0b325c;
}

#contrasteAzul nav ul li a,
#contrasteAzul .row-top,
#contrasteAzul .row-banner,
#contrasteAzul .row-content,
#contrasteAzul .row-content .box p,
#contrasteAzul .row-content .box i,
#contrasteAzul .row-banner h1 span,
#contrasteAzul footer {
  color: #FFFFFF;
}

#contrasteAzul nav ul li a.contraste-active {
  color: #0b325c;
  background: #FFFFFF;
}

#contrasteAzul .row-banner .avatar {
  border: 5px solid #FFFFFF;
}
/*END - Contraste azul*/
!

JS 

              
                /*
Artigo : Contraste de cores
Autor : Orivelton Cesar - www.orivelton.com.br
*/

//Selecionando os links de contraste
var linksContraste = document.querySelectorAll('nav a[data-contraste]');

//Function click passando o valor do data-contraste para a function contraste setar o Id no body
linksContraste.forEach(linksContraste => linksContraste.addEventListener('click', function() {
    var dataContraste = this.dataset.contraste; // pegando o data-contraste da tag 'a'
    contraste(dataContraste); // Chamando  a function contraste com um parâmetro passado pelo data-contraste da tag 'a'
  }
));

function contraste(dataContraste) {
  var setId;
  //Verificação de qual contraste foi selecionado
  if (dataContraste == 1) {
    setId = 'contrasteBranco';
  } else if (dataContraste == 2) {
    setId = 'contrastePreto';
  } else if (dataContraste == 3) {
    setId = 'contrasteAzul';
  } else {
    setId = ''
  }
  // setando o ID do contraste escolhido no body
  document.querySelector("body").setAttribute("id", setId);
  // Guardando o cookie do contraste
  document.cookie = "contraste=" + setId + "";
}

// Verificação do cookie
var cookieContrasteBranco = document.cookie.indexOf('contrasteBranco');
var cookieContrastePreto = document.cookie.indexOf('contrastePreto');
var cookieContrasteAzul = document.cookie.indexOf('contrasteAzul');

//Verificando o cookie setado anteriormente
var cookieTrue = '';
if (cookieContrasteBranco != -1) {
  cookieTrue = 1;
} else if (cookieContrastePreto != -1) {
  cookieTrue = 2;
} else if (cookieContrasteAzul != -1) {
  cookieTrue = 3;
} else {
  cookieTrue = '';
}
//Chamando a function contraste com o valor do cookie guardado
contraste(cookieTrue);
!
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