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ul {
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.ytk-00-MathJye_mi {
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div.ytk-00-quizPutTag {
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.ytk-00-fenshu i,
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del.ytk-01-hide {
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del.ytk-01-blur {
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[class^="koba-"] span[editor-math-model] span,
[class^="koba-"] span[math-model] span {
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[class^="koba-"] > .divider:first-child {
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[class^="koba-"] .divider {
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[class^="koba-"] .label-header > hr {
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span[editor-math-model] span,
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table.cke_show_border,
span.MathTable table {
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span.MathTable table td {
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div.UserInput {
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span.ytk-02-ud {
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}
span.ytk-02-ud:before {
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}
span.exerconnectionimg,
span.exerimg {
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img.list_image {
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td.ucqo_frac_denominator {
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}
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}
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}
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}
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}
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  padding: 0px 0.4em;
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}
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}
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.ytk-00-ucqo_matrix .ytk-00-ucqo_matrix_fr {
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.ytk-00-ucqo_equalmark,
.ucqo_equalmark {
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.ytk-00-ucqo_equalmark_table .ytk-00-ucqo_equalmark_top,
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.ytk-00-ucqo_equalmark_table .ytk-00-ucqo_equalmark_top,
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.ytk-00-ucqo_equalmark_table .ytk-00-ucqo_equalmark_bottom,
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}
.ytk-00-ucqo_arrow_table,
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}
.ytk-00-ucqo_arrow_table .ytk-00-ucqo_arrow_top,
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}
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}
.ytk-00-ucqo_arrow_left_arrow,
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}
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}
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}
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}
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}
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}
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}
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}
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}
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}
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}
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}
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}
table.ytk-00-edittable {
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}
table.ytk-00-edittable th,
table.ytk-00-edittable td {
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}
.ytk-00-ucqo_frac {
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}
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}
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}
.ytk-00-ucqo_frac_frac .ytk-00-ucqo_frac_numerator,
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.ytk-00-ucqo_frac_frac .ytk-00-ucqo_frac_denominator {
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}
.ytk-00-ucqo_frac_frac .ytk-00-ucqo_frac_denominator,
.ytk-00-ucqo_frac .frac-denominator {
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}
.ytk-00-ucqo_script_full {
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}
.ytk-00-ucqo_script_full .ytk-00-ucqo_script_body,
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  margin-left: -5px;
}
.ytk-00-ucqo_script_full .ytk-00-ucqo_script_sup,
.ytk-00-ucqo_script_full .ytk-00-ucqo_script_sub,
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}
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.ytk-00-ucqo_script_full .ytk-00-ucqo_script_sub > sub,
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.ucqo_script_full .ucqo_script_sub > sub {
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}
.ytk-00-ucqo_pc .ytk-00-ucqo_script_front {
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}
.ytk-00-ucqo_text {
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}
.ytk-00-ucqo_root .ytk-00-ucqo_root_index {
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}
.ytk-00-ucqo_repeat_repeat {
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}
.ytk-00-ucqo_repeat_dot {
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  margin-top: -1.15em;
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  font-weight: bold;
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  font-family: "Symbola-mq", "Times New Roman", serif;
}
.ytk-00-ucqo_repeat_one .ytk-00-ucqo_repeat_dot {
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}
.ytk-00-ucqo_repeat_right {
  float: left;
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}
.ytk-00-ucqo_repeat_left {
  float: right;
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}
.ytk-00-ucqo_tof > li {
  display: inline-block;
}
.ytk-00-ucqo_operator {
  margin: 0 0.1em;
}
.ytk-00-ucqo_operator .ytk-00-ucqo_operator_main {
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  text-align: center;
}
.ytk-00-ucqo_operator .ytk-00-ucqo_operator_o {
  line-height: 1em;
  display: block;
}
.ytk-00-ucqo_operator .ytk-00-ucqo_operator_lower {
  line-height: 1em;
  font-size: 0.6em;
  display: block;
}
.ytk-00-ucqo_operator .ytk-00-ucqo_operator_upper {
  line-height: 1em;
  font-size: 0.6em;
  display: block;
}
.ytk-00-ucqo_limit .ytk-00-ucqo_operator_main {
  margin-bottom: -0.1em;
}
.ytk-00-ucqo_limit .ytk-00-ucqo_operator_lower {
  margin-bottom: -7px;
}
.ytk-00-ucqo_sum .ytk-00-ucqo_operator_o {
  line-height: 0.8em;
  padding-top: 0.10em;
  font-size: 1.6em;
}
.ytk-00-ucqo_sum .ytk-00-ucqo_operator_main {
  margin-top: -0.2em;
}
table.edittable {
  border-collapse: collapse;
  text-align: center;
  line-height: 1.3em;
}
table.edittable > tr > th,
table.edittable > tr > td {
  padding: 8px;
  border: 1px solid;
}
table.edittable > tbody > tr > th,
table.edittable > tbody > tr > td {
  padding: 8px;
  border: 1px solid;
}
.ytk-00-ucqo_grid {
  display: inline-block;
  vertical-align: middle;
}
.ytk-00-ucqo_grid .ytk-00-ucqo_grid_fl {
  float: left;
}
.ytk-00-ucqo_grid .ytk-00-ucqo_grid_fr {
  float: left;
  margin-left: 1em;
}
.ytk-00-ucqo_arc {
  line-height: 1em;
  display: inline-block;
  text-align: center;
  vertical-align: baseline;
}
.ytk-00-ucqo_arc .ytk-00-ucqo_arc_main {
  display: block;
  line-height: 0.8em;
  height: 0.8em;
}
.ytk-00-ucqo_arc .ytk-00-ucqo_arc_header {
  display: block;
}
.ytk-00-ucqo_strike {
  text-decoration: line-through;
}
.ytk-03-Math table {
  display: inline-block;
  vertical-align: middle;
  text-align: center;
}
ol.q-xz {
  list-style-type: none;
}
ol.q-xz div.xx {
  display: inline-block;
}
@font-face {
  font-family: MathJax_Main;
  src: url('./df3ef3d5-MathJax_Main.ttf');
  font-weight: 400;
  font-style: normal;
}
.fM,
.font-math-regular,
.wb_math,
.wb_physics,
.wb_biology,
.wb_chemistry,
.glossary {
  font-family: MathJax_Main;
  font-weight: 400;
  font-style: normal;
}
@font-face {
  font-family: MathJax_Math-Italic;
  src: url('./554d7a67-MathJax_Italic.ttf');
  font-weight: 400;
  font-style: normal;
}
.fI,
div[class^="koba-"] .special_italic {
  font-family: MathJax_Math-Italic;
  font-weight: 400;
  font-style: italic;
}
@font-face {
  font-family: MathJax_AMS;
  src: url('./455d5fd0-MathJax_AMS.ttf');
  font-weight: 400;
  font-style: normal;
}
.fAMS {
  font-family: MathJax_AMS;
  font-weight: 400;
  font-style: normal;
}
@font-face {
  font-family: MathJax_Size1-Regular;
  src: url('./796d4d90-MathJax_S1.ttf');
  font-weight: 400;
  font-style: normal;
}
.fS1 {
  font-family: MathJax_Size1-Regular;
  font-weight: 400;
  font-style: normal;
}
@font-face {
  font-family: MathJax_Size2-Regular;
  src: url('./0850fe03-MathJax_S2.ttf');
  font-weight: 400;
  font-style: normal;
}
.fS2 {
  font-family: MathJax_Size2-Regular;
  font-weight: 400;
  font-style: normal;
}
@font-face {
  font-family: MathJax_Size3-Regular;
  src: url('./12e792ab-MathJax_S3.ttf');
  font-weight: 400;
  font-style: normal;
}
.fS3 {
  font-family: MathJax_Size3-Regular;
  font-weight: 400;
  font-style: normal;
}
@font-face {
  font-family: MathJax_Size4-Regular;
  src: url('./65b1417b-MathJax_S4.ttf');
  font-weight: 400;
  font-style: normal;
}
.fS4 {
  font-family: MathJax_Size4-Regular;
  font-weight: 400;
  font-style: normal;
}
span.dI {
  display: inline-block;
}
span.pA {
  position: absolute;
}
span.pR {
  position: relative;
}
span.pS {
  position: static;
}
span.oH {
  overflow: hidden;
}
.pt1 table,
.pt2 table,
.pt5 table,
.pt6 table {
  display: inline-block;
  vertical-align: middle;
}
.pt1 table td,
.pt2 table td,
.pt5 table td,
.pt6 table td {
  padding: 1px;
  white-space: nowrap;
  width: auto;
  _height: auto;
}
.pt1 span,
.pt2 span,
.pt5 span,
.pt6 span {
  text-align: left;
  line-height: normal;
  border: 1;
  display: inline-block;
}
.pt1 .MathJax span {
  vertical-align: initial;
}
span[mathtag=math] table {
  vertical-align: middle;
  display: inline-table;
}
span[mathtag=math] table td {
  text-align: center;
}
.FEBox {
  background-color: #FFF;
  position: relative;
  margin-left: 2px;
  margin-right: 2px;
  white-space: nowrap;
  font-size: 0;
  overflow: visible;
  display: inline-block;
  _display: inline;
  zoom: 1;
  border-bottom: #1d887b solid 1px;
  min-width: 30px;
  line-height: normal;
  padding: 2px 3px 4px 3px;
  _padding: 2px 20px 4px 5px;
}
.topiclist li {
  display: inline-block;
  *display: inline;
  *zoom: 1;
  padding: 5px 0;
  vertical-align: top;
}
.topiclist li .list_Option {
  min-height: 20px;
  _height: 20px;
  margin-right: 10px;
  margin-left: 40px;
}
.topiclist li .list_Option img {
  vertical-align: top;
}
.topiclist li .li_option_titie {
  width: 40px;
  color: #333;
  *display: inline;
  *zoom: 1;
  margin-left: -40px;
}
.topiclist li .input {
  margin: 3px 3px 0 0;
  margin-top: -1px;
  margin-right: 2px;
  margin-left: -4px;
  position: relative;
}
.topiclist li .label {
  font-family: "Times New Roman", Times, serif;
  margin-right: 0;
  position: relative;
  font-size: 16px;
  font-weight: bold;
  color: #0f54a8;
}
.topiclist li .label dfn {
  position: absolute;
  left: -25px;
  top: -4px;
  top: -3px;
  *top: -1px;
  display: none;
  width: 23px;
  height: 24px;
  margin: 0;
  padding: 0;
  overflow: hidden;
}
.topiclist li .label dfn.wrong {
  display: block;
  background-position: 0 0;
}
.topiclist li .label dfn.Corrector {
  display: block;
  background-position: 0 -41px;
}
.topiclist_1 li {
  width: 98%;
}
.topiclist_2 li {
  width: 48%;
}
.topiclist_3 li {
  width: 32%;
}
.topiclist_4 li {
  width: 23%;
}
.topictitle .topiclist,
.topicbody .topiclist {
  margin-left: 0;
}
.T-or-F {
  display: inline-block;
  *display: inline;
  zoom: 1;
  color: #222;
  font-style: normal;
  padding: 0 5px;
}
.T-or-F dfn {
  display: inline-block;
  *display: inline;
  zoom: 1;
  width: 18px;
  height: 16px;
  margin: 0;
  padding: 0 2px;
  vertical-align: -4px;
  *vertical-align: middle;
  cursor: pointer;
  overflow: hidden;
}
.T-or-F input {
  float: left;
  margin-left: -30px;
  _margin-bottom: -20px;
}
.T-or-F label {
  display: block;
  width: 18px;
  height: 16px;
  margin: 0;
  padding: 0;
  overflow: hidden;
  cursor: pointer;
}
.T-or-F .true {
  background-position: 0 -70px;
}
.T-or-F .false {
  background-position: 0 -90px;
}
.T-or-F .hot .true {
  background-position: 0 -110px;
}
.T-or-F .hot .false {
  background-position: 0 -130px;
}
.or-F {
  color: #be0000;
}
.or-F .true {
  display: none;
}
.or-F .false {
  display: none;
}
.or-F dfn {
  border-bottom: red solid 1px;
}
.or-F label,
.or-T label {
  cursor: default;
}
.or-F .hot .true {
  display: block;
}
.or-F .hot .false {
  display: block;
}
.TorF-answer {
  display: inline-block;
  *display: inline;
  zoom: 1;
  width: 16px;
  height: 16px;
  overflow: hidden;
}
.TorF-answer-T {
  background-position: 0 -110px;
}
.TorF-answer-F {
  background-position: 0 -130px;
}
body {
  font-family: sans-serif;
  margin: 0;
  padding: 0;
  word-wrap: break-word;
}
* {
  margin: 0;
  padding: 0;
}
.float-l {
  float: left;
}
.float-r {
  float: right;
}
.text-muted {
  color: #666666;
}
.video-stamp {
  height: 10px;
  overflow: visible;
  text-align: right;
  padding-right: 5px;
}
.video-stamp img {
  width: 46px;
  height: 46px;
  margin-top: -21px;
}
.section-content {
  -webkit-text-size-adjust: 100%;
  -moz-text-size-adjust: 100%;
  -ms-text-size-adjust: 100%;
}
.question-group-guide-item {
  background-image: -webkit-gradient(linear, left top, right top, from(rgba(61, 148, 255, 0.6)), to(rgba(61, 148, 255, 0.6))) !important;
  background-image: -webkit-linear-gradient(left, rgba(61, 148, 255, 0.6) 0%, rgba(61, 148, 255, 0.6) 100%) !important;
  background-image: -moz-linear-gradient(left, rgba(61, 148, 255, 0.6) 0%, rgba(61, 148, 255, 0.6) 100%) !important;
  background-image: -o-linear-gradient(left, rgba(61, 148, 255, 0.6) 0%, rgba(61, 148, 255, 0.6) 100%) !important;
  background: linear-gradient(90deg, rgba(61, 148, 255, 0.6) 0%, rgba(61, 148, 255, 0.6) 100%) !important;
  background-position: 0 16px !important;
  background-repeat: repeat-x !important;
  -webkit-background-size: 2px 4px !important;
  -moz-background-size: 2px 4px !important;
  -o-background-size: 2px 4px !important;
  background-size: 2px 4px !important;
}
.show-teacher-guide-item {
  background-image: -webkit-gradient(linear, left top, right top, from(rgba(61, 148, 255, 0.6)), to(rgba(61, 148, 255, 0.6))) !important;
  background-image: -webkit-linear-gradient(left, rgba(61, 148, 255, 0.6) 0%, rgba(61, 148, 255, 0.6) 100%) !important;
  background-image: -moz-linear-gradient(left, rgba(61, 148, 255, 0.6) 0%, rgba(61, 148, 255, 0.6) 100%) !important;
  background-image: -o-linear-gradient(left, rgba(61, 148, 255, 0.6) 0%, rgba(61, 148, 255, 0.6) 100%) !important;
  background: linear-gradient(90deg, rgba(61, 148, 255, 0.6) 0%, rgba(61, 148, 255, 0.6) 100%) !important;
  background-position: 0 16px !important;
  background-repeat: repeat-x !important;
  -webkit-background-size: 2px 4px !important;
  -moz-background-size: 2px 4px !important;
  -o-background-size: 2px 4px !important;
  background-size: 2px 4px !important;
}
.big-img-adjust,
.section-content img.native,
*[q-type] img {
  max-width: 100%;
  height: auto;
  -webkit-tap-highlight-color: transparent;
}
.drag-container::-webkit-scrollbar {
  display: none;
}
.box.android-solar .content {
  background-color: #FFFFFF;
}
.box.android-solar .content .border-1px {
  border: 1px solid;
}
@media screen and (-webkit-min-device-pixel-ratio: 2) {
  .box.android-solar .content .border-1px {
    border: 1px solid;
  }
  .box.android-solar .content .border-1px {
    border: 0.5px solid;
  }
}
.box.android-solar .content .border-1px-top {
  border-top: 1px solid;
}
@media screen and (-webkit-min-device-pixel-ratio: 2) {
  .box.android-solar .content .border-1px-top {
    border-top: 1px solid;
  }
  .box.android-solar .content .border-1px-top {
    border-top: 0.5px solid;
  }
}
.box.android-solar .content .section-header {
  font-size: 20px;
  padding: 32px 16px 0;
  font-weight: bold;
  line-height: 28px;
  color: #272727;
  position: relative;
}
.box.android-solar .content .section-content {
  font-size: 16px;
  padding: 24px 16px 0;
  word-break: break-all;
  word-wrap: break-word;
  white-space: pre-line;
  background: transparent;
}
.box.android-solar .content .section-content,
.box.android-solar .content .section-content * {
  font-weight: normal !important;
  line-height: 30px;
}
.box.android-solar .content .section-content *:not(sup):not(sub) {
  font-size: 16px !important;
}
.box.android-solar .content .section-content .mjx-chtml * {
  line-height: 0;
}
.box.android-solar .content .section-content img {
  vertical-align: middle;
}
.box.android-solar .content .scholar-image {
  width: 100%;
  padding: 0 16px;
  box-sizing: border-box;
  margin-top: 16px;
}
.box.android-solar .content .section-question-group-guide {
  padding: 0 16px 0;
}
.box.android-solar .content .section-question-group-guide .question-group-guide {
  box-sizing: border-box;
  padding: 6px 12px;
  background: rgba(61, 148, 255, 0.1) !important;
  border-radius: 16px;
  font-size: 12px;
  color: #3D94FF;
  margin-right: 12px;
  margin-top: 12px;
  display: inline-block;
  max-width: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
  vertical-align: middle;
  white-space: nowrap;
}
.box.android-solar .content .section-tag {
  padding: 10px 16px 0;
}
.box.android-solar .content .section-tag .tag {
  background-color: #F8F8F8 !important;
  border-radius: 4px;
  color: #909090;
  font-size: 10px;
  margin-top: 6px;
  margin-right: 6px;
  padding: 4px 8px;
  display: inline-block;
}
.box.android-solar .content .section-ios-placeholder {
  padding: 0 16px;
  height: 32px;
}
.box.android-solar .content .section-android-placeholder {
  padding: 0 16px;
  height: 32px;
}
.box.android-solar .content .section-wrapper-padding {
  padding-bottom: 24px;
}
.box.android-solar .content .section-wrapper-padding img {
  vertical-align: middle;
}
.box.android-solar .content .section-separator {
  height: 0;
  margin: 24px 16px;
  border-color: #E9E9E9;
}
.box.android-solar .content .section-subheader {
  margin: 0 16px;
  font-size: 17px;
  font-weight: bold;
  color: #272727;
  position: relative;
  padding-left: 24px;
}
.box.android-solar .content .section-subheader:before,
.box.android-solar .content .section-subheader:after {
  content: '';
  border-radius: 50px;
  display: inline-block;
  width: 10px;
  height: 10px;
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  -webkit-transform: translateY(-50%);
}
.box.android-solar .content .section-subheader:before {
  left: 0;
  background-color: #9dcaff;
}
.box.android-solar .content .section-subheader:after {
  left: 6px;
  background-color: #61aaff;
}
.box.android-solar .content .section-subcontent {
  font-size: 16px;
  padding: 16px 16px 0;
  line-height: 30px;
  word-break: break-all;
  word-wrap: break-word;
  background: transparent;
  white-space: pre-line;
}
.box.android-solar .content .section-comment {
  margin-top: 16px;
  padding: 0 16px;
  font-size: 14px;
  color: #7A7A7A;
  line-height: 21.5px;
}
.box.android-solar .content .feedback-button {
  width: 80px;
  height: 32px;
  font-size: 14px;
  color: #7A7A7A;
  margin: 16px 16px 0;
  background-color: #ffffff;
  border-color: #CECECE;
  border-radius: 16px;
}
.box.android-solar .content .automatic-answer {
  font-size: 16px;
  padding: 24px 16px;
  word-break: break-all;
  word-wrap: break-word;
  background: transparent;
}
.box.android-solar .content .automatic-answer-share {
  padding: 32px 16px;
}
.box.android-solar .content .automatic-answer-share .block-answer-502:last-of-type {
  margin-bottom: 0px;
}
.box.android-solar .content .automatic-answer img {
  vertical-align: middle;
}
.box.android-solar .content .automatic-answer div[class*="block-answer-item-"] {
  display: none;
}
.box.android-solar .content .automatic-answer .block-answer-600 img,
.box.android-solar .content .automatic-answer .block-answer-602 img {
  width: 100%;
}
.box.android-solar .content .automatic-answer .block-answer-601 {
  color: #272727;
}
.box.android-solar .content .automatic-answer .block-answer-601 ol {
  list-style-type: none;
  counter-reset: sectioncounter;
  line-height: 23px;
}
.box.android-solar .content .automatic-answer .block-answer-601 ol li {
  padding-left: 30px;
  text-indent: -30px;
  margin-bottom: 8px;
  word-break: break-word;
}
.box.android-solar .content .automatic-answer .block-answer-601 ol li:before {
  content: "(" counter(sectioncounter) ")";
  counter-increment: sectioncounter;
  margin-right: 12.5px;
}
.box.android-solar .content .automatic-answer .block-answer-500 {
  margin-bottom: 16px;
}
.box.android-solar .content .automatic-answer .block-answer-500:last-of-type {
  margin-bottom: 0px;
}
.box.android-solar .content .automatic-answer .block-answer-error {
  color: #909090;
  font-size: 16px;
  padding: 16px 0px;
  text-align: center;
}
.box.android-solar .content .automatic-answer .block-answer-item.block-answer-item-active {
  display: block;
}
.box.android-solar .content .automatic-answer .block-answer-501 {
  position: relative;
}
.box.android-solar .content .automatic-answer .block-answer-501 .block-answer-501-item {
  padding: 0 0 8px 0;
  width: 100%;
  box-sizing: border-box;
  word-break: break-all;
}
.box.android-solar .content .automatic-answer .block-answer-501 .block-answer-501-item img {
  object-fit: contain;
}
.box.android-solar .content .automatic-answer .block-answer-511 {
  position: relative;
}
.box.android-solar .content .automatic-answer .block-answer-511 .block-answer-511-item {
  display: flex;
  flex-wrap: wrap;
  margin-right: -13px;
}
.box.android-solar .content .automatic-answer .block-answer-511 .block-answer-511-item .block-answer-511-span {
  max-width: 90vw;
  display: inline-block;
  margin: 0 13px 23px 0;
}
.box.android-solar .content .automatic-answer .block-answer-511 .block-answer-511-item .block-answer-511-span img {
  max-width: 90vw;
  object-fit: contain;
}
.box.android-solar .content .automatic-answer .block-answer-502 {
  margin: 0px 0px 16px 19px;
  position: relative;
}
.box.android-solar .content .automatic-answer .block-answer-502 .block-answer-title {
  position: relative;
}
.box.android-solar .content .automatic-answer .block-answer-502 .block-answer-title:after {
  content: '';
  position: absolute;
  top: 50%;
  left: -19px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  margin-top: -6px;
  background: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAACcAAAAnCAMAAAC7faEHAAAAVFBMVEUAAAA9lf8+lf89lf9Blf9Blv9Al/9Vqv89lf8/lf8/mP8+lf8+lf8+lf89lf8+lf89lf89lv89lf8+lf8/lf89lP8/lf9Gl/9JpP9Alf89lf89lP+d8dKLAAAAG3RSTlMA8OOeNCwjBt5lOdbKxbuYiYV9c1lPRBYODPV45/k6AAABF0lEQVQ4y5VU1wKDIAx0D7Tunf//z5pERcQWuJemx+ViGPE0rIlIVu8/4q70AeGXXfxLlOYZ3JHl6ZtsLOCJYtTNQnhD+LCcP8AI6n6Yhr4OgPGZFVl2pEcXFR0FspswZbcqVpuv2FGW5tTGe6LhIlen9Df3dOS0Mh5VC8UtEZNIFMcilUkV80t7nEe7MFHJUtRrzE0GcCKIuBnq+YpClm0gsbEwPF06DIhbyE06LpSLYbcHJVKU2oKKllhMLvdf/PAaCYwU+MTWHK3I9LQh8ARtT4/RyqsDEkLTCaQHyuDVCYlJ00la2PrZfp9lv7b7Z3setudreV9s75/TfTa/D6f3Zn6/zvPAPF/M88p5/pnnqft8Ns/7L3wLSfxz38FOAAAAAElFTkSuQmCC') no-repeat center;
  background-size: cover;
}
.box.android-solar .content .automatic-answer .block-answer-tab-tip {
  font-size: 14px;
  line-height: 20px;
  color: #909090;
  margin: 16px 0px 12px;
}
.box.android-solar .content .automatic-answer .block-answer-tab {
  border: 1px solid transparent;
  background: #F4F4F4;
  border-radius: 6px;
  display: inline-block;
  font-size: 14px;
  color: #272727;
  margin-right: 12px;
  margin-bottom: 10px;
  padding: 6px 12px;
  line-height: 15px;
}
.box.android-solar .content .automatic-answer .block-answer-tab-active {
  background: rgba(61, 148, 255, 0.1);
  border: 1px solid #3D94FF;
  border-radius: 6px;
  font-size: 14px;
  color: #3D94FF;
}
.box.android-solar .content .automatic-answer .block-answer-tip {
  font-size: 16px;
  line-height: 23px;
  margin-bottom: 8px;
  letter-spacing: 0;
}
.box.android-solar .content .automatic-answer .block-answer-tip:last-of-type {
  margin-bottom: 0px;
}
.box.android-solar .content .automatic-answer .block-answer-403 {
  margin-bottom: 16px;
}
.box.android-solar .content .automatic-answer .block-answer-403:last-of-type {
  margin-bottom: 0px;
}
.box.android-solar .content .automatic-answer .block-answer-solution {
  font-size: 16px;
  line-height: 23px;
  color: #272727;
  margin: 8px 0px;
}
.box.android-solar .content .automatic-answer .block-answer-dot {
  position: relative;
}
.box.android-solar .content .automatic-answer .block-answer-dot:after {
  content: '';
  position: absolute;
  top: 100%;
  left: 50%;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  margin-left: -2px;
  background-color: #000;
}
.box.android-solar .content .automatic-answer img {
  display: block;
  pointer-events: none;
  margin-bottom: 8px;
}
.box.android-solar .content .automatic-answer .solution-tip {
  font-size: 12px;
  line-height: 17px;
  color: #909090;
  margin-top: 16px;
}
.box.android-solar .content .automatic-answer .smart-calculator-wrapper {
  background: #FFFFFF;
  box-shadow: 0 2px 8px 0 rgba(0, 0, 0, 0.1);
  border-radius: 12px;
  height: 80px;
  padding: 0px 16px;
  margin-top: 16px;
}
.box.android-solar .content .automatic-answer .smart-calculator {
  height: 100%;
  overflow: hidden;
  position: relative;
}
.box.android-solar .content .automatic-answer .smart-calculator img {
  float: left;
  height: 40px;
  width: 40px;
  position: absolute;
  top: 50%;
  left: 0px;
  margin-top: -20px;
}
.box.android-solar .content .automatic-answer .smart-calculator .smart-calculator-desc {
  margin-left: 52px;
  margin-top: 18px;
}
.box.android-solar .content .automatic-answer .smart-calculator .smart-calculator-desc .smart-calculator-desc-title {
  font-size: 17px;
  color: #272727;
  line-height: 24px;
  padding-bottom: 4px;
  font-weight: bold;
}
.box.android-solar .content .automatic-answer .smart-calculator .smart-calculator-desc .smart-calculator-desc-tip {
  font-size: 12px;
  color: #909090;
  line-height: 16px;
}
.box.android-solar .content .automatic-answer .smart-calculator .smart-calculator-arrow {
  opacity: 0.64;
  background: #CECECE;
  width: 22px;
  height: 22px;
  position: absolute;
  top: 50%;
  right: 0px;
  margin-top: -11px;
  border-radius: 50%;
}
.box.android-solar .content .automatic-answer .smart-calculator .smart-calculator-arrow:after {
  display: inline-block;
  content: "";
  color: #FFFFFF;
  height: 6px;
  width: 6px;
  border-width: 2px 2px 0 0;
  border-color: #FFFFFF;
  border-style: solid;
  transform: matrix(0.71, 0.71, -0.71, 0.71, 0, 0);
  position: absolute;
  top: 50%;
  left: 6px;
  margin-top: -4px;
}
.box.android-solar .content .cyber-uw {
  -webkit-text-decoration-line: underline;
  text-decoration-line: underline;
  -webkit-text-decoration-style: wavy;
  text-decoration-style: wavy;
}
.box.android-solar .content .cyber-ud {
  -webkit-text-emphasis-style: circle;
  text-emphasis-style: circle;
  -webkit-text-emphasis-position: under;
  text-emphasis-position: under left;
  -webkit-text-emphasis-color: black;
  text-emphasis-color: black;
}
.cyber-uw {
  -webkit-text-decoration-line: underline;
  text-decoration-line: underline;
  -webkit-text-decoration-style: wavy;
  text-decoration-style: wavy;
}
.cyber-ud {
  -webkit-text-emphasis-style: circle;
  text-emphasis-style: circle;
  -webkit-text-emphasis-position: under;
  text-emphasis-position: under left;
  -webkit-text-emphasis-color: black;
  text-emphasis-color: black;
}
.download-wrap {
  text-align: left;
  height: 85px;
  border-bottom: solid 1px #dcdcdc;
  background: #FFFFFF;
  margin: 0;
  padding: 0;
}
.download-wrap * {
  margin: 0;
  padding: 0;
}
.download-wrap .icon {
  margin: 15px 20px 0 10px;
  position: absolute;
  top: 0;
  left: 0;
}
.download-wrap .title {
  display: inline-block;
  margin: 10px 0 0 85px;
}
.download-wrap .title .row1 {
  line-height: 24px;
  font-size: 14px;
  color: #666;
}
.download-wrap .title .row2,
.download-wrap .title .row3 {
  line-height: 22px;
  font-size: 12px;
}
.download-wrap .title .mute {
  color: #99a7b0;
}
.download-wrap .title .star-filled {
  background: url('./f86d1d66-star.png') no-repeat;
  background-size: contain;
  display: inline-block;
  width: 12px;
  height: 12px;
  margin-right: 5px;
}
.download-wrap .download-btn {
  display: inline-block;
  font-size: 12px;
  background: #0099ff;
  color: #FFFFFF;
  text-align: center;
  line-height: 25px;
  width: 60px;
  height: 25px;
  text-decoration: none;
  margin: 30px 10px 30px 0;
  position: absolute;
  right: 0;
  top: 0;
}
body,
h3,
p {
  margin: 0;
  padding: 0;
}
html {
  overflow-x: hidden;
}
body {
  font-size: 15px;
  background: #f6f6f6;
  width: 100%;
  max-width: 100%;
  overflow-x: hidden;
}
.content {
  background-color: #FFFFFF;
  border-top: 1px solid #ededed;
}
.section-separator-div {
  height: 12px;
  background-color: #F4F4F4;
  margin-top: 32px;
}
.section-image {
  text-align: center;
  padding: 9px 10px 0;
}
.section-image img {
  display: block;
  margin: 0 auto 9px;
}
.section-image img {
  max-width: 100%;
  max-height: 300px;
}
.video-wrapper {
  padding: 10px 10px 20px;
}
.video-desc {
  position: absolute;
  bottom: 6px;
  color: #FFFFFF;
  font-size: 13px;
  z-index: 2;
}
.video-size {
  left: 8px;
}
.video-duration {
  right: 8px;
}
img.video-preview {
  height: 100%;
  width: auto;
}
.video-player-controller {
  height: 100%;
  width: 100%;
  position: absolute;
  left: 0;
  top: 0;
  z-index: 1;
  background-color: rgba(14, 45, 62, 0.23);
  cursor: pointer;
  text-align: middle;
  line-height: 115px;
}
.video-player-controller img {
  vertical-align: middle;
}
.video-player {
  position: relative;
  display: inline-block;
  height: 115px;
  width: 204px;
  text-align: center;
}
.text-muted {
  color: #999999;
}
.toast,
.vip-toast {
  box-sizing: border-box;
  color: #ffffff;
  font-size: 15px;
  line-height: 24px;
  background-color: rgba(0, 0, 0, 0.7);
  width: 270px;
  padding: 20px;
  border-radius: 5px;
  display: none;
  position: fixed;
  top: 200px;
  left: 50%;
  margin-left: -135px;
  z-index: 100;
}
@media only screen and (min-device-width: 1224px) {
  body {
    overflow: auto;
  }
}
.block-splitter {
  height: 12px;
  display: block;
  background: #F9F9F9;
}
.flex-cont {
  display: -webkit-box;
  display: -webkit-flex;
  display: flex;
}
.flex-item {
  -webkit-box-flex: 1;
  -webkit-flex: 1;
  flex: 1;
}
.full-width {
  width: 100%;
}
.ugc-title {
  font-family: PingFangSC-Medium, arial, sans-serif;
  font-size: 16px;
  color: #333;
  letter-spacing: 0;
  line-height: 16px;
  padding: 20px 0 0 20px;
  background: white;
}
.ugc-title span.highlight {
  color: #0099FF;
}
.rank-item {
  position: relative;
  padding-bottom: 12px;
  height: 80px;
  width: 100%;
  border-radius: 5px;
  background: white;
}
.rank-item .user-medal {
  min-width: 50px;
  text-align: center;
  opacity: 1;
  margin-top: 29px;
}
.rank-item .user-medal img {
  width: 22px;
}
.rank-item .user-medal p {
  font-size: 18px;
  line-height: 18px;
}
.rank-item .user-avatar {
  min-width: 50px;
  margin-top: 20px;
  margin-left: 20px;
}
.rank-item .user-avatar img {
  width: 40px;
  height: 40px;
  border-radius: 20px;
}
.rank-item .user-info {
  overflow: hidden;
  margin-top: 20px;
}
.rank-item .user-info .user-name {
  font-size: 16px;
  line-height: 16px;
  color: #333333;
  letter-spacing: 0;
  font-family: PingFangSC-Medium, sans-serif;
  margin-bottom: 12px;
}
.rank-item .user-info .user-name .name {
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
  -ms-text-overflow: ellipsis;
  -o-text-overflow: ellipsis;
}
.rank-item .user-info .user-name .level-img {
  min-width: 16px;
  max-width: 59px;
  height: 16px;
  margin-left: 6px;
}
.rank-item .user-info .user-name .level-img img {
  width: 100%;
}
.rank-item .user-info .user-school {
  font-family: PingFangSC-Regular, sans-serif;
  font-size: 12px;
  color: #666666;
  letter-spacing: 0;
  line-height: 12px;
}
.rank-item .user-info .user-school .school {
  text-overflow: ellipsis;
  overflow: hidden;
  white-space: nowrap;
  -ms-text-overflow: ellipsis;
  -o-text-overflow: ellipsis;
}
.rank-item .user-info .user-school .grade {
  min-width: 54px;
  white-space: nowrap;
}
.rank-item .beat-count {
  min-width: 80px;
  margin-left: auto;
  margin-top: 20px;
  white-space: nowrap;
  text-align: center;
  font-size: 20px;
  font-family: DINCondersed-Bold, arial, sans-serif;
  color: #333;
  letter-spacing: 0;
  line-height: 20px;
}
.rank-item .beat-count .label {
  margin-top: 6px;
  font-family: PingFangSC-Regular, arial, sans-serif;
  font-size: 12px;
  color: #666;
  letter-spacing: 0;
  line-height: 12px;
}
.rank-item .float-beat-count {
  position: absolute;
  right: 16px;
  margin-right: 0 !important;
}
.rank-item .beat-info {
  text-align: right;
  min-width: 70px;
  margin-right: 16px;
  margin-left: auto;
  white-space: nowrap;
  margin-top: 16px;
}
.rank-item .beat-info .beat-num {
  font-family: DINCondersed-Bold, sans-serif;
  font-size: 23px;
  line-height: 23px;
  margin-bottom: 8px;
}
.navigator-home {
  margin: 10px 12px;
  font-size: 16px;
  line-height: 44px;
  color: #ffffff;
  text-align: center;
  background: #0099ff;
  border-radius: 5px;
}