Issues using Bootstrap

I'm using a full image bootstrap but my image besides not being altered is getting in the middle of the screen. I wanted the login screen padding to be restricted to its size, but it's taking half the screen. Here is the css code:

body {
    margin-top: 50px; 
}

.full {
    background: "img/bg.JPG";
    -webkit-background-size: cover;
    -moz-background-size: cover;
    background-size: cover;
    -o-background-size: cover;
}

Now follows the html part where I enter a small login field:

<form method="post" name="frmIndex" id="frmIndex" action="autenticausuario.php"><br><br><br><br><br><br><br><br>
    <div id="login" style="width: 460px; background-color: #21374c; margin-left: 35%; height: 160px;">
                <div id ="img" style=" float: left;">
                    <img src="img/logocodap.png" style="width: 160px; height: 160px;"/>
                </div>
        <div id="acesso" style="float: left; width: 280px;">

            <div id="nnn" style="font-size: 30px; text-align: center; color: white; float: left; margin-left: 20px;  margin-bottom: 10px;">
                    <p><b>nnnnnnnnnnn</b></p>
                </div>
                <div id="aut" style=" float: left;">
                    <div id="labels" style="float: left; margin-left: 20px; color: white;">
                        <label>ID:</label><br><br>
                        <label>SENHA:</label>
                    </div>
                    <div id="labels" style="float: right;">
                        <label><input type="text" name="id" id="id" style="width: 130px;" /></label><br><br>
                        <label><input type="password" name="senha" id="senha"  style="width: 130px;" /></label>
                    </div>

                    <div id="labels" style="float: left;">
                        <br>
                        <p style=" margin-left: 125px;"><input type="submit" value="Entrar" id="botao_entrar" id="botao_entrar"/></p>
                    </div>


             </div>
        </div>       
     </div>
</form>