我是 CSS 新手，刚刚构建了一个应用程序。问题是，在验证 CSS 时，我收到以下错误和警告：
有人可以解释这些错误和警告的含义以及如何修复它以便可以验证 CSS 吗？
尽管有这些错误，我的应用程序仍能正常运行。
这是我的 CSS 代码：
/*----------------------------CSS reset------------------------------*/
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;
}
ol, ul {
list-style: none;
}
blockquote, q {
quotes: none;
}
blockquote:before, blockquote:after, q:before, q:after {
content: '';
content: none;
}
table {
border-collapse: collapse;
border-spacing: 0;
}
/*-----------App wrapper-----------*/
#wrapper {
padding-left: 1em;
padding-right: 1em;
}
/*-----------App description-----------*/
h1 {
font-size: 24px;
font-family: helvetica;
font-weight: bold;
text-align: center;
padding-top: 1em;
padding-bottom: 1em;
}
p {
font-size: 16px;
font-family: helvetica;
text-align:justify;
line-height: 1.2;
}
/*-----------Select menu-----------*/
#input {
padding-top: 1em;
padding-bottom: 1em;
}
#search_button, label select {
padding: 10px 10px 10px 10px;
background: #f8f8f8;
color: #444;
border: 1px solid black;
border-radius: 0;
display: inline-block;
-webkit-appearance: none;
-moz-appearance: none;
appearance: none;
cursor: pointer;
outline: none;
font-family: helvetica;
font-size: 13px;
}
#search_button, label select:-moz-focusring {
color: transparent;
text-shadow: 0 0 0 #444;
}
#search_button, label select::-ms-expand {
display: none;
}
label:before {
content: '';
right: 5px;
top: -7px;
width: 30px;
height: 33px;
background: #f8f8f8;
position: absolute;
pointer-events: none;
display: block;
}
label { position: relative; }
label:after {
content: '>';
font: 16px helvetica, monospace;
color: #444;
-webkit-transform: rotate(90deg);
-moz-transform: rotate(90deg);
-ms-transform: rotate(90deg);
transform: rotate(90deg);
right: 2px;
top: -3px;
border-bottom: 1px solid #aaa;
position: absolute;
pointer-events: none;
width: 35px;
padding: 0 0 5px 0;
text-indent: 14px;
}
/*-----------Crest, Name-----------*/
#output {
display: -webkit-box; /* OLD - iOS 6-, Safari 3.1-6 */
display: -moz-box; /* OLD - Firefox 19- (buggy but mostly works) */
display: -ms-flexbox; /* TWEENER - IE 10 */
display: -webkit-flex; /* NEW - Chrome */
display:flex;
max-height: 70px;
}
#crest {
max-height: 70px;
max-width: 70px;
}
img {
max-height: 100%;
float: left;
}
#team-name {
width: 100%;
}
h2 {
font-size: 17px;
font-family: helvetica;
font-weight: bold;
text-align: center;
vertical-align: middle;
line-height: 70px;
}
/*-----------Geochart container-----------*/
/*-----------Pie chart container-----------*/
#pie-container {
display: block;
}
/*----------------------------Tablet responsive----------------------------*/
@media all and (min-width: 700px) {
/*-----------App decription-----------*/
h1 {
font-size: 50px;
}
p {
font-size: 16px;
}
/*-----------Crest, Name-----------*/
#output {
max-height: 120px;
}
#crest {
max-height: 120px;
max-width: 120px;
}
h2 {
font-size: 38px;
line-height: 120px;
}
}
/*----------------------------Desktop responsive----------------------------*/
@media all and (min-width: 900px) {
/*-----------App wrapper-----------*/
#wrapper {
padding-left: 5em;
padding-right: 5em;
}
/*-----------App decription-----------*/
h1 {
font-size: 60px;
}
p {
font-size: 18px;
}
/*-----------Crest, Name-----------*/
#output {
max-height: 160px;
}
#crest {
max-height: 160px;
max-width: 160px;
}
h2 {
font-size: 40px;
line-height: 160px;
}
/*-----------Pie chart container-----------*/
#pie-container {
display: -webkit-box; /* OLD - iOS 6-, Safari 3.1-6 */
display: -moz-box; /* OLD - Firefox 19- (buggy but mostly works) */
display: -ms-flexbox; /* TWEENER - IE 10 */
display: -webkit-flex; /* NEW - Chrome */
display:flex;
}
#countryPie {
flex: 1;
}
#playerPie {
flex: 1;
}
}
谢谢你的帮助！