body
has default margins: http://www.w3.org/TR/CSS2/sample.html
body { margin:0; } /* Remove body margins */
Or you could use this useful Global reset
* { margin:0; padding:0; box-sizing:border-box; }
If you want something less *
global than:
html, body, body div, span, object, iframe, h1, h2, h3, h4, h5, h6, p, blockquote, pre, abbr, address, cite, code, del, dfn, em, img, ins, kbd, q, samp, small, strong, sub, sup, var, b, i, dl, dt, dd, ol, ul, li, fieldset, form, label, legend, table, caption, tbody, tfoot, thead, tr, th, td, article, aside, figure, footer, header, hgroup, menu, nav, section, time, mark, audio, video {
margin: 0;
padding: 0;
border: 0;
outline: 0;
font-size: 100%;
vertical-align: baseline;
background: transparent;
}
some other CSS Reset:
http://yui.yahooapis.com/3.5.0/build/cssreset/cssreset-min.css
http://meyerweb.com/eric/tools/css/reset/
https://github.com/necolas/normalize.css/
http://html5doctor.com/html-5-reset-stylesheet/
…