“En 10 segundos se desvanecen en una tarjeta HTML CSS” Código de respuesta

En 10 segundos se desvanecen en una tarjeta HTML CSS

Your issue stems from applying two animations at once that you actually want to run in sequence. To get this working reliably you have two options:

CSS only: http://jsfiddle.net/marionebl/M9LR6/

Note opacity: 0; to keep the message hidden when the animation completes. Plus: This won't work in IE <= 9, it does not support keyframe animations: http://caniuse.com/#feat=css-animation

@keyframes fadeInOut {
    0% {
        opacity: 0;
    }
    16% {
       opacity: 1;
    }
    84% {
       opacity: 1;
    }
    100% {
       opacity: 0;
    }
}

.message {
    width: 400px;
    margin: 0 auto;
    opacity: 0;
    text-align: center;
   -webkit-animation: fadeInOut 6s;
   animation: fadeInOut 6s;
}
Involving JS: http://jsfiddle.net/marionebl/P26c9/1/

Is somewhat more flexible and easier to change, supports IE9.

CSS:

@-webkit-keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@-webkit-keyframes fadeOut {
    from {
        opacity: 1;
    }
    to {
        opacity: 0;
    }
}
@keyframes fadeOut {
    from {
        opacity: 1;
    }
    to {
        opacity: 0;
    }
}

.fadeIn {
    -webkit-animation: fadeIn;
    animation: fadeIn;
    opacity: 1;
}

.fadeOut {
    -webkit-animation: fadeOut;
    animation: fadeOut;
    opacity: 0;
}

.fast {
    -webkit-animation-duration: 1s;
    animation-duration: 1s
}

.message {
    width: 400px;
    margin: 0 auto;
    text-align: center;
}
JS:

var $message = $('.message');
$message.addClass('fadeIn fast');

setTimeout(function(){
   $message.removeClass('fadeIn').addClass('fadeOut');
}, 5000);