#ValentinesContainer 
{
    position: fixed;
    width: calc(100% - 100px);
    height: 100vh;
    z-index:1; 
    pointer-events:none;
}
#ValentinesContainer > div 
{
    position: absolute;
    width: 50px;
    height: 50px;
    
    /* We use the following properties to apply the fade and drop animations to each Valentines.
       Each of these properties takes two values. These values respectively match a setting
       for fade and drop.
    */
    -webkit-animation-iteration-count: infinite, infinite;
    -webkit-animation-direction: normal, normal;
    -webkit-animation-timing-function: linear, ease-in;
}

/* This CSS rule is applied to all img elements directly inside div elements which are
   directly inside the ValentinesContainer div. In other words, it matches the 'img' elements
   inside the ValentinesDivs which are created in the createAValentines() function.
*/
#ValentinesContainer > div > img {
     position: absolute;
     width: 50px;
     height: 50px;

    /* We use the following properties to adjust the clockwiseSpin or counterclockwiseSpinAndFlip
       animations on each Valentines.
       The createAValentines function in the Valentines.js file determines whether a Valentines has the 
       clockwiseSpin or counterclockwiseSpinAndFlip animation.
    */
     -webkit-animation-iteration-count: infinite;
     -webkit-animation-direction: alternate;
     -webkit-animation-timing-function: ease-in-out;
     -webkit-transform-origin: 30% -100%;
}


/* Hides a Valentines towards the very end of the animation */
@-webkit-keyframes fade
{
    /* Show a Valentines while into or below 95 percent of the animation and hide it, otherwise */
    0%   { opacity: 1; }
    95%  { opacity: 1; }
    100% { opacity: 0; }
}


/* Makes a Valentines fall from -300 to 600 pixels in the y-axis */
@-webkit-keyframes drop
{
    /* Move a Valentines to -300 pixels in the y-axis at the start of the animation */
    0%   { -webkit-transform: translate(-50px, -50px); }
    /* Move a Valentines to 600 pixels in the y-axis at the end of the animation */
    100% { -webkit-transform: translate(0px, 100vh); }
}

/* Rotates a Valentines from -50 to 50 degrees in 2D space */
@-webkit-keyframes clockwiseSpin
{
    /* Rotate a Valentines by -50 degrees in 2D space at the start of the animation */
    0%   { -webkit-transform: rotate(-50deg); }
    /*  Rotate a Valentines by 50 degrees in 2D space at the end of the animation */
    100% { -webkit-transform: rotate(50deg); }
}


/* Flips a Valentines and rotates it from 50 to -50 degrees in 2D space */
@-webkit-keyframes counterclockwiseSpinAndFlip 
{
    /* Flip a Valentines and rotate it by 50 degrees in 2D space at the start of the animation */
    0%   { -webkit-transform: scale(-1, 1) rotate(50deg); }
    /* Flip a Valentines and rotate it by -50 degrees in 2D space at the end of the animation */
    100% { -webkit-transform: scale(-1, 1) rotate(-50deg); }
}