Device Orientation API

window.addEventListener('deviceorientation', function(event) {
    event.alpha = 0;
    event.beta = 0;
    event.gamma = 0;
}, false);

Screen Orientation API

screen.orientation.addEventListener('change', function() {
    screen.orientation.type = "landscape-primary";
    screen.orientation.angle = 0;
}, false);

Window Orientation

window.addEventListener("orientationchange", function() {
    screen.orientation.angle = ;
}, false);

CSS Mediaqueries

@media screen and (orientation:portrait) {
    /* styles spécifiques à l'orientation portrait */
}

@media screen and (orientation:landscape) {
    /* styles spécifiques à l'orientation paysage */
}

var mediaQueryList = window.matchMedia("(orientation: portrait)");

mediaQueryList.addListener(function(mql) { 
    mql.matches = ; 
});