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<label for="ex1">Input :disabled</label><br />
<input id="ex1" type="text" disabled />
<br /><br />
<label for="ex2">Input :enabled</label><br />
<input id="ex2" type="text" />
<br /><br />
<label for="ex3">Clique no input para visualizar o :focus</label><br />
<input id="ex3" type="text" />
<br /><br />
<label for="ex4">Input de email invalido</label><br />
<input id="ex4" type="email" value="meu_email_mal_formatado"/>
<br /><br />
<label for="ex5">Input de email valido</label><br />
<input id="ex5" type="email" value="meu_email@gmail.com"/>
<br /><br />
<label for="ex6">Input que está dentro dos limites</label><br />
<input id="ex6" type="number" min="0" max="100" value="36" />
<br /><br />
<label for="ex7">Input que está FORA dos limites</label><br />
<input id="ex7" type="number" min="0" max="100" value="402" />
<br /><br />
<label for="ex8">Input opcional</label><br />
<input id="ex8" type="text" />
<br /><br />
<label for="ex9">Input obrigatório</label><br />
<input id="ex9" type="text" required />
<br /><br />
<label for="ex10">Input disponível somente para leitura :read-only</label><br />
<input id="ex10" type="text" value="esse post é demais" readonly />
<br /><br />
<label for="ex11">Input input que pode ser alterado e lido :read-write</label><br />
<input id="ex11" type="text" value="você pode alterar isso" />
<br /><br />
label{font-family: Verdana, sans-serif;font-size: 14px;}
/* inputs desabilitados ficarão com fundo
vermelho e bordas pretas*/
input:disabled{
background-color: red;
border: 1px solid #000;
}
/* o input com id #ex2 que estiver habilitado
ficaá com cor de fundo amarela e letras pretas */
input#ex2:enabled{
background-color: yellow;
color: #000;
}
/* o input com o id #ex3 que estiver com foco do usuario
ficará com uma borda de 2px azul*/
input#ex3:focus{
border: 2px solid blue;
}
/* o input com id #ex4 com conteudo invalido
terá uma borda vermelha */
input#ex4:invalid{
border-color: red;
}
/* o input com id #ex5 valido ficará com fundo
verde e letras brancas */
input#ex5:valid{
background-color: green;
color: #fff;
}
/* o input que estiver dentro do range irá ter
borda verde */
input:in-range{
border-color: green;
}
/* o input que estiver fora do range ficará com
fundo rosa */
input:out-of-range{
background-color: pink;
}
/* o input com id #ex8 e que for opcional ficará
com fundo verde escuro e letras brancas */
input#ex8:optional{
background-color: #003300;
color: #fff;
}
/* o input que for obrigatório
ficará com fundo vermelho escuro e letras brancas */
input:required {
background-color: #660000;
color: #fff;
}
/* o input que estiver disponivel somente para leitura
ficará com fundo cinza e borda cinza escuro */
input:read-only{
background: #e3e3e3;
border: 1px solid #666;
}
/* o input com id #ex11 e disponivel para edição sem a tag
readonly ficará com fundo laranja e letras brancas*/
input#ex11:read-write{
background: #ff3300;
color: #fff;
}
Also see: Tab Triggers