*{
    box-sizing: border-box;
}


body{
    background-image: url(../img/pattern.gif);
}
    #contenedor {
         width: 95%;
        height: 450px;
        margin: auto 20px;
        background-color: #999;
        display: flex;
        flex-wrap: wrap;
        padding: 10px;
        justify-content: space-between;
    }
    #titulo {
        width: 100%;
        height: 100px;
        background: #cccccc;
        text-align: center;
        border-bottom: 10px double #666666;
        font-size: 40px;
      
    }
    #bloque1{
        width: 32%;
        height: 150px;
        background: #ffffcc;
        padding: 10px;
        text-align: left;
        font-size: 30px;

    }
    #bloque2{
        width: 32%;
        height: 150px;
        background: #ccccff;
        padding: 10px;
        text-align: center;
        font-size: 30px;
        margin: 0 2% 0 2%;
        float: left;
    }
    #bloque3{
        width: 32%;
        height: 150px;
        background: #ffcccc;
        padding: 10px;
        text-align: right;
        font-size: 30px;
    }