Generate cross browser transitons CSS (includes custom easing functions)

transitionCss.js

/**
 * Create cross browser transition CSS
 *
 * @param {Integer} duration Duration in milliseconds.
 * @param {String} easing Easing function. Can be built-in CSS3 function or one of the provided custom functions.
 * @param {String} prop CSS property to apply transition to.
 */
function transitionCss(duration, easing, prop) {
    var easingDefs = {
        easeInCubic     : 'cubic-bezier(0.550, 0.055, 0.675, 0.190)',
        easeOutCubic    : 'cubic-bezier(0.215, 0.610, 0.355, 1.000)',
        easeInOutCubic  : 'cubic-bezier(0.645, 0.045, 0.355, 1.000)',
        easeInCirc      : 'cubic-bezier(0.600, 0.040, 0.980, 0.335)',
        easeOutCirc     : 'cubic-bezier(0.075, 0.820, 0.165, 1.000)',
        easeInOutCirc   : 'cubic-bezier(0.785, 0.135, 0.150, 0.860)',
        easeInExpo      : 'cubic-bezier(0.950, 0.050, 0.795, 0.035)',
        easeOutExpo     : 'cubic-bezier(0.190, 1.000, 0.220, 1.000)',
        easeInOutExpo   : 'cubic-bezier(1.000, 0.000, 0.000, 1.000)',
        easeInQuad      : 'cubic-bezier(0.550, 0.085, 0.680, 0.530)',
        easeOutQuad     : 'cubic-bezier(0.250, 0.460, 0.450, 0.940)',
        easeInOutQuad   : 'cubic-bezier(0.455, 0.030, 0.515, 0.955)',
        easeInQuart     : 'cubic-bezier(0.895, 0.030, 0.685, 0.220)',
        easeOutQuart    : 'cubic-bezier(0.165, 0.840, 0.440, 1.000)',
        easeInOutQuart  : 'cubic-bezier(0.770, 0.000, 0.175, 1.000)',
        easeInQuint     : 'cubic-bezier(0.755, 0.050, 0.855, 0.060)',
        easeOutQuint    : 'cubic-bezier(0.230, 1.000, 0.320, 1.000)',
        easeInOutQuint  : 'cubic-bezier(0.860, 0.000, 0.070, 1.000)',
        easeInSine      : 'cubic-bezier(0.470, 0.000, 0.745, 0.715)',
        easeOutSine     : 'cubic-bezier(0.390, 0.575, 0.565, 1.000)',
        easeInOutSine   : 'cubic-bezier(0.445, 0.050, 0.550, 0.950)',
        easeInBack      : 'cubic-bezier(0.600, -0.280, 0.735, 0.045)',
        easeOutBack     : 'cubic-bezier(0.175, 0.885, 0.320, 1.275)',
        easeInOutBack   : 'cubic-bezier(0.680, -0.550, 0.265, 1.550)'
    }

    if (typeof prop === 'undefined') {
        prop = 'all';
    }
    if (typeof easing === 'undefined') {
        easing = 'ease-in';
    }

    var val = prop+' '+(duration/1000)+'s '+easingDefs[easing];

    return {
        '-webkit-transition': val,
        '-moz-transition': val,
        '-o-transition': val,
        '-ms-transition': val,
        'transition': val
    };
};