css - run-time error CSS1019: Unexpected token, found '@charset' -

i have css stylesheet contains following code:

@charset "utf-8"; /* css document */  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, 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;     vertical-align: baseline; } 

i facing these errors

/* minification failed. returning unminified contents. (1189,1): run-time error css1019: unexpected token, found '@charset' (1189,10): run-time error css1019: unexpected token, found '"utf-8"' (1189,17): run-time error css1019: unexpected token, found ';'

only 1 @charset may appear in css , must appear @ start of document. must not preceded characters, not comments.

most of time, it's due bundle css along 'css' files.
guess that, using bunch of css'es in single bundle , the topmost css in bundled files, can have @charset "utf-8".
therefore can set @charset "utf-8" @ topmost css file in bundle statement (and make sure haven't use @charset declaration other "utf-8" if so, need split bundled files separate bundles, every @charset accommodate @ top of it's bundle order).

note: since http header has higher precedence in-document @charset declaration, may want omit @charset statements , declare in http header.