1. pc-reset PC 样式初始化

/* normalize.css */

html {
  line-height: 1.15;
  /* 1 */
  -ms-text-size-adjust: 100%;
  /* 2 */
  -webkit-text-size-adjust: 100%;
  /* 2 */
}

body {
  margin: 0;
}

article,
aside,
footer,
header,
nav,
section {
  display: block;
}

h1 {
  font-size: 2em;
  margin: 0.67em 0;
}

figcaption,
figure,
main {
  /* 1 */
  display: block;
}

figure {
  margin: 1em 40px;
}

hr {
  box-sizing: content-box;
  /* 1 */
  height: 0;
  /* 1 */
  overflow: visible;
  /* 2 */
}

pre {
  font-family: monospace, monospace;
  /* 1 */
  font-size: 1em;
  /* 2 */
}

a {
  background-color: transparent;
  /* 1 */
  -webkit-text-decoration-skip: objects;
  /* 2 */
}

abbr[title] {
  border-bottom: none;
  /* 1 */
  text-decoration: underline;
  /* 2 */
  text-decoration: underline dotted;
  /* 2 */
}

b,
strong {
  font-weight: inherit;
}

b,
strong {
  font-weight: bolder;
}

code,
kbd,
samp {
  font-family: monospace, monospace;
  /* 1 */
  font-size: 1em;
  /* 2 */
}

dfn {
  font-style: italic;
}

mark {
  background-color: #ff0;
  color: #000;
}

small {
  font-size: 80%;
}

sub,
sup {
  font-size: 75%;
  line-height: 0;
  position: relative;
  vertical-align: baseline;
}

sub {
  bottom: -0.25em;
}

sup {
  top: -0.5em;
}

audio,
video {
  display: inline-block;
}

audio:not([controls]) {
  display: none;
  height: 0;
}

img {
  border-style: none;
}

svg:not(:root) {
  overflow: hidden;
}

button,
input,
optgroup,
select,
textarea {
  font-family: sans-serif;
  /* 1 */
  font-size: 100%;
  /* 1 */
  line-height: 1.15;
  /* 1 */
  margin: 0;
  /* 2 */
}

button,
input {
  /* 1 */
  overflow: visible;
}

button,
select {
  /* 1 */
  text-transform: none;
}

button,
html [type="button"],

/* 1 */

[type="reset"],
[type="submit"] {
  -webkit-appearance: button;
  /* 2 */
}

button::-moz-focus-inner,
[type='button']::-moz-focus-inner,
[type='reset']::-moz-focus-inner,
[type='submit']::-moz-focus-inner {
  border-style: none;
  padding: 0;
}

button:-moz-focusring,
[type='button']:-moz-focusring,
[type='reset']:-moz-focusring,
[type='submit']:-moz-focusring {
  outline: 1px dotted ButtonText;
}

fieldset {
  padding: 0.35em 0.75em 0.625em;
}

legend {
  box-sizing: border-box;
  /* 1 */
  color: inherit;
  /* 2 */
  display: table;
  /* 1 */
  max-width: 100%;
  /* 1 */
  padding: 0;
  /* 3 */
  white-space: normal;
  /* 1 */
}

progress {
  display: inline-block;
  /* 1 */
  vertical-align: baseline;
  /* 2 */
}

textarea {
  overflow: auto;
}

[type='checkbox'],
[type='radio'] {
  box-sizing: border-box;
  /* 1 */
  padding: 0;
  /* 2 */
}

[type='number']::-webkit-inner-spin-button,
[type='number']::-webkit-outer-spin-button {
  height: auto;
}

[type='search'] {
  -webkit-appearance: textfield;
  /* 1 */
  outline-offset: -2px;
  /* 2 */
}

[type='search']::-webkit-search-cancel-button,
[type='search']::-webkit-search-decoration {
  -webkit-appearance: none;
}

::-webkit-file-upload-button {
  -webkit-appearance: button;
  /* 1 */
  font: inherit;
  /* 2 */
}

details,

/* 1 */

menu {
  display: block;
}

summary {
  display: list-item;
}

canvas {
  display: inline-block;
}

template {
  display: none;
}

[hidden] {
  display: none;
}

/* reset */

html,
body,
h1,
h2,
h3,
h4,
h5,
h6,
div,
dl,
dt,
dd,
ul,
ol,
li,
p,
blockquote,
pre,
hr,
figure,
table,
caption,
th,
td,
form,
fieldset,
legend,
input,
button,
textarea,
menu {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

2. Phone-reset

/* normalize.css */

html {
  line-height: 1.15;
  /* 1 */
  -ms-text-size-adjust: 100%;
  /* 2 */
  -webkit-text-size-adjust: 100%;
  /* 2 */
}

body {
  margin: 0;
}

article,
aside,
footer,
header,
nav,
section {
  display: block;
}

h1 {
  font-size: 2em;
  margin: 0.67em 0;
}

figcaption,
figure,
main {
  /* 1 */
  display: block;
}

figure {
  margin: 1em 40px;
}

hr {
  box-sizing: content-box;
  /* 1 */
  height: 0;
  /* 1 */
  overflow: visible;
  /* 2 */
}

pre {
  font-family: monospace, monospace;
  /* 1 */
  font-size: 1em;
  /* 2 */
}

a {
  background-color: transparent;
  /* 1 */
  -webkit-text-decoration-skip: objects;
  /* 2 */
}

abbr[title] {
  border-bottom: none;
  /* 1 */
  text-decoration: underline;
  /* 2 */
  text-decoration: underline dotted;
  /* 2 */
}

b,
strong {
  font-weight: inherit;
}

b,
strong {
  font-weight: bolder;
}

code,
kbd,
samp {
  font-family: monospace, monospace;
  /* 1 */
  font-size: 1em;
  /* 2 */
}

dfn {
  font-style: italic;
}

mark {
  background-color: #ff0;
  color: #000;
}

small {
  font-size: 80%;
}

sub,
sup {
  font-size: 75%;
  line-height: 0;
  position: relative;
  vertical-align: baseline;
}

sub {
  bottom: -0.25em;
}

sup {
  top: -0.5em;
}

audio,
video {
  display: inline-block;
}

audio:not([controls]) {
  display: none;
  height: 0;
}

img {
  border-style: none;
}

svg:not(:root) {
  overflow: hidden;
}

button,
input,
optgroup,
select,
textarea {
  font-family: sans-serif;
  /* 1 */
  font-size: 100%;
  /* 1 */
  line-height: 1.15;
  /* 1 */
  margin: 0;
  /* 2 */
}

button,
input {
  /* 1 */
  overflow: visible;
}

button,
select {
  /* 1 */
  text-transform: none;
}

button,
html [type="button"],

/* 1 */

[type="reset"],
[type="submit"] {
  -webkit-appearance: button;
  /* 2 */
}

button::-moz-focus-inner,
[type='button']::-moz-focus-inner,
[type='reset']::-moz-focus-inner,
[type='submit']::-moz-focus-inner {
  border-style: none;
  padding: 0;
}

button:-moz-focusring,
[type='button']:-moz-focusring,
[type='reset']:-moz-focusring,
[type='submit']:-moz-focusring {
  outline: 1px dotted ButtonText;
}

fieldset {
  padding: 0.35em 0.75em 0.625em;
}

legend {
  box-sizing: border-box;
  /* 1 */
  color: inherit;
  /* 2 */
  display: table;
  /* 1 */
  max-width: 100%;
  /* 1 */
  padding: 0;
  /* 3 */
  white-space: normal;
  /* 1 */
}

progress {
  display: inline-block;
  /* 1 */
  vertical-align: baseline;
  /* 2 */
}

textarea {
  overflow: auto;
}

[type='checkbox'],
[type='radio'] {
  box-sizing: border-box;
  /* 1 */
  padding: 0;
  /* 2 */
}

[type='number']::-webkit-inner-spin-button,
[type='number']::-webkit-outer-spin-button {
  height: auto;
}

[type='search'] {
  -webkit-appearance: textfield;
  /* 1 */
  outline-offset: -2px;
  /* 2 */
}

[type='search']::-webkit-search-cancel-button,
[type='search']::-webkit-search-decoration {
  -webkit-appearance: none;
}

::-webkit-file-upload-button {
  -webkit-appearance: button;
  /* 1 */
  font: inherit;
  /* 2 */
}

details,

/* 1 */

menu {
  display: block;
}

summary {
  display: list-item;
}

canvas {
  display: inline-block;
}

template {
  display: none;
}

[hidden] {
  display: none;
}

/* reset */

html,
body,
h1,
h2,
h3,
h4,
h5,
h6,
div,
dl,
dt,
dd,
ul,
ol,
li,
p,
blockquote,
pre,
hr,
figure,
table,
caption,
th,
td,
form,
fieldset,
legend,
input,
button,
textarea,
menu {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html,
body {
  /* 禁止选中文本 */
  -webkit-user-select: none;
  user-select: none;
  font: Oswald, 'Open Sans', Helvetica, Arial, sans-serif;
}

/* 禁止长按链接与图片弹出菜单 */

a,
img {
  -webkit-touch-callout: none;
}

/*ios android去除自带阴影的样式*/

a,
input {
  -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
}

input[type='text'] {
  -webkit-appearance: none;
}

3. 公共样式提取

/* 禁止选中文本 */
.usn {
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  -o-user-select: none;
  user-select: none;
}
/* 浮动 */
.fl {
  float: left;
}
.fr {
  float: right;
}
.cf {
  zoom: 1;
}
.cf:after {
  content: '.';
  display: block;
  clear: both;
  visibility: hidden;
  height: 0;
  overflow: hidden;
}

/* 元素类型 */
.db {
  display: block;
}
.dn {
  display: none;
}
.di {
  display: inline;
}
.dib {
  display: inline-block;
}
.transparent {
  opacity: 0;
}

/*文字排版、颜色*/
.f12 {
  font-size: 12px;
}
.f14 {
  font-size: 14px;
}
.f16 {
  font-size: 16px;
}
.f18 {
  font-size: 18px;
}
.f20 {
  font-size: 20px;
}
.fb {
  font-weight: bold;
}
.fn {
  font-weight: normal;
}
.t2 {
  text-indent: 2em;
}
.red,
a.red {
  color: #cc0031;
}
.darkblue,
a.darkblue {
  color: #039;
}
.gray,
a.gray {
  color: #878787;
}
.lh150 {
  line-height: 150%;
}
.lh180 {
  line-height: 180%;
}
.lh200 {
  line-height: 200%;
}
.unl {
  text-decoration: underline;
}
.no_unl {
  text-decoration: none;
}
.tl {
  text-align: left;
}
.tc {
  text-align: center;
}
.tr {
  text-align: right;
}
.tj {
  text-align: justify;
  text-justify: inter-ideograph;
}
.wn {
  /* 强制不换行 */
  word-wrap: normal;
  white-space: nowrap;
}
.wb {
  /* 强制换行 */
  white-space: normal;
  word-wrap: break-word;
  word-break: break-all;
}
.wp {
  /* 保持空白序列*/
  overflow: hidden;
  text-align: left;
  white-space: pre-wrap;
  word-wrap: break-word;
  word-break: break-all;
}
.wes {
  /* 多出部分用省略号表示 , 用于一行 */
  overflow: hidden;
  word-wrap: normal;
  white-space: nowrap;
  text-overflow: ellipsis;
}
.wes-2 {
  /* 适用于webkit内核和移动端 */
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 2;
  overflow: hidden;
}
.wes-3 {
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 3;
  overflow: hidden;
}
.wes-4 {
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 4;
  overflow: hidden;
}

/* 溢出样式 */
.ofh {
  overflow: hidden;
}
.ofs {
  overflow: scroll;
}
.ofa {
  overflow: auto;
}
.ofv {
  overflow: visible;
}

/* 定位方式 */
.ps {
  position: static;
}
.pr {
  position: relative;
  zoom: 1;
}
.pa {
  position: absolute;
}
.pf {
  position: fixed;
}

/* 垂直对齐方式 */
.vt {
  vertical-align: top;
}
.vm {
  vertical-align: middle;
}
.vb {
  vertical-align: bottom;
}

/* 鼠标样式 */
.csd {
  cursor: default;
}
.csp {
  cursor: pointer;
}
.csh {
  cursor: help;
}
.csm {
  cursor: move;
}

/* flex布局 */
.df-sb {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.df-sa {
  display: flex;
  align-items: center;
  justify-content: space-around;
}

/* 垂直居中 */
.df-c {
  display: flex;
  align-items: center;
  justify-content: center;
}
.tb-c {
  text-align: center;
  display: table-cell;
  vertical-align: middle;
}
.ts-c {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
}
.ts-mc {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  top: 0;
  margin: auto;
}

/* 辅助 */
.mask-fixed-wrapper {
  width: 100%;
  height: 100%;
  position: fixed;
  left: 0;
  top: 0;
  background: rgba(0, 0, 0, 0.65);
  z-index: 999;
}
.bg-cover {
  background-size: cover;
  background-repeat: no-repeat;
  background-position: center center;
}
.bg-cover-all {
  background-size: 100% 100%;
  background-repeat: no-repeat;
  background-position: center center;
}