/*  JavaScript 7th Edition
    Chapter 8
    Hands-on Project 8-2

    Filename: styles.css
*/

/* apply a natural box layout model to all elements */
* {
   -moz-box-sizing: border-box;
   -webkit-box-sizing: border-box;
   box-sizing: border-box;
}

/* reset rules */
html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
b, u, i, center,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td,
article, aside, canvas, details, embed, 
figure, figcaption, footer, header, hgroup, 
menu, nav, output, ruby, section, summary,
time, mark, audio, video {
   margin: 0;
   padding: 0;
   border: 0;
   font-size: 100%;
   font: inherit;
   vertical-align: baseline;
}

/* HTML5 display-role reset for older browsers */
article, aside, details, figcaption, figure, 
footer, header, hgroup, menu, nav, section {
   display: block;
}

body {
   line-height: 1;
   width: 960px;
   background: white;
   margin: 0 auto;
   font-family: Verdana, Geneva, sans-serif; 
}

ol, ul {
   list-style: none;
}

/* page header */
header {
   background: #5472B2;
   width: 100%;
   color: #FFFFFF;
   font-size: 48px;
   text-align: center;
   line-height: 1.5em;
   margin-bottom: 0;
}



/*-------------------- Project Styles ------------------*/

section {
   background-color: #FFDB70;
   margin-top: 0;
   padding-bottom: 20px;
   user-select:none;
   height: 570px;
   position: relative;
}

section h1 {
   font-size: 2.8em;
   text-align: center;
   margin: 0;
   padding: 20px 0;
}

div#box {
   width: 800px;
   height: 400px;
   border: 0px solid rgba(120, 120, 120, 0.5);
   background-color: ivory;
   position: relative;
   margin: 10px auto;
   top: 0px;
   left: 0px;
   box-shadow: 5px 5px 10px gray;
}

div.ball {
   position: absolute;
   background:radial-gradient(closest-corner at 25% 25%, rgba(92, 151, 170, 0.1) 0, rgba(92, 151, 170, 0.5) 100%);
   border: 1px solid transparent;
   width: 60px;
   height: 60px;
   border-radius: 50%;
   cursor: pointer;
}


input#addBall {
   display: block;
   width: 120px;
   height: 30px;
   margin: 25px auto;
   font-size: 1.2em;
   cursor: pointer;
}