/* common */
ol{list-style-type:none;counter-reset:sectioncounter}
ol li:before {
   content:counter(sectioncounter) "."; 
   counter-increment:sectioncounter;
}
iframe{
    display: block;
    margin: 0 auto;
    width: 100%;
}
.advertise {
    width: 100%;
    display: flex;
    justify-content: center;
  }
  .badge {
    display: inline-block;
    padding: 0.25em 0.4em;
    font-size: 75%;
    font-weight: 700;
    line-height: 1;
    text-align: center;
    white-space: nowrap;
    vertical-align: baseline;
    border-radius: 0.25rem;
  }
  .badge-danger {
    color: #fff;
    background-color: #dc3545;
  }
  .badge-primary {
    color: #fff;
    background-color: #007bff;
  }
  .search-box .box {
    display: flex;
    justify-content: center;
    width: 100%;
  }
  .search-box .keyword {
    width: 65%;
    height: 16px;
    padding: 16px;
    font-size: 16px;
    margin: 0;
    vertical-align: top;
    box-shadow: none;
    border-radius: 10px 0 0 10px;
    border: 2px solid #c4c7ce;
    background: #fff;
    color: #222;
    overflow: hidden;
    box-sizing: content-box;
    border-right: 0;
    transition: border-color 0.4s ease;
  }
  .search-box .keyword:focus {
    border-color: #4285f4;
  }
  .search-box .keyword:not(:focus):hover {
    border-color: #a7aab5;
  }
  .search-box .search_btn {
    cursor: pointer;
    background-color: #4285f4;
    border-radius: 0 10px 10px 0;
    font-size: 17px;
    color: #fff;
    box-shadow: none;
    font-weight: 400;
    border: none;
    outline: 0;
    width: 17%;
    transition: background-color 0.4s ease;
  }
  .search-box .search_btn:hover {
    background: #3668bc;
  }
  /* navbar */
  .navbar {
    font-size: 0;
    padding: 10px 0;
    border-bottom: 1px solid #efefef;
    position: relative;
  }
  .navbar .container {
    width: 1200px;
    display: flex;
    align-items: center;
  }
  .navbar .nav_logo {
    width: 120px;
    display: block;
  }
  .navbar .search-box {
    width: 50%;
    margin-left: 30px;
  }
  .navbar .search-box .keyword {
    width: 70%;
    padding: 12px;
  }
  .navbar .search-box .search_btn {
    width: 30%;
  }
  .navbar .nav_list {
    margin-left: auto;
  }
  .navbar .nav_list a {
    color: #4285f4;
    transition: color 0.4s ease;
    font-size: 20px;
  }
  .navbar .nav_list a:hover {
    color: #3668bc;
    text-decoration: underline;
  }
  .navbar .nav_list a + a {
    margin-left: 30px;
  }
  header .menu {
    cursor: pointer;
    user-select: none;
    float: right;
    align-items: center;
    font-size: 0;
    display: none;
  }
  header .menu .in {
    background: #4285f4;
    border-radius: 4px;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
  }
  header .menu span,
  header .menu span:after,
  header .menu span:before {
    display: inline-block;
    height: 2px;
    width: 19px;
    background: #fff;
    transition: top 0.2s linear;
  }
  header .menu span {
    transition: all 0.2s 0.4s ease;
    position: relative;
  }
  header .menu span:after,
  header .menu span:before {
    position: absolute;
    left: 0;
    content: '';
    transform-origin: 50% 50%;
    transition: top 0.2s 0.4s ease, transform 0.4s ease;
    height: 2px;
  }
  header .menu span:before {
    top: 6px;
  }
  header .menu span:after {
    top: -6px;
  }
  header .menu.active span {
    transition: all 0.2s 0s ease;
    background: 0 0;
  }
  header .menu.active span:after,
  header .menu.active span:before {
    transition: top 0.2s ease, transform 0.2s 0.3s ease;
    top: 0;
    width: 19px;
  }
  header .menu.active span:before {
    transform: rotate3d(0, 0, 1, 45deg);
  }
  header .menu.active span:after {
    transform: rotate3d(0, 0, 1, -45deg);
  }
  .search_mb {
    margin-left: auto;
    width: 30px;
    height: 30px;
    align-items: center;
    justify-content: center;
    border-radius: 4px;
    background: #4285f4;
    color: #fff;
    display: none;
  }
  .search_mb .close {
    display: none;
  }
  .search_mb.active .close {
    display: block;
  }
  .search_mb.active .icon {
    display: none;
  }
  body.PC .navbar .nav_list {
    display: block !important;
  }
  /* footer */
  footer {
    border-top: 1px solid #efefef;
    padding: 20px 0;
  }
  .footer_sns {
    text-align: center;
    display: flex;
    justify-content: center;
    font-size: 0;
  }
  .footer_sns a {
    display: inline-block;
    color: #1b1e25;
    padding: 3px;
    transition: all 0.4s ease;
    border-radius: 5px;
  }
  .footer_sns a:hover {
    background-color: #2c66d4;
    color: #fff;
  }
  .footer_sns a + a {
    margin-left: 20px;
  }
  /* layout */
  .container {
    width: 1032px;
    padding: 0 16px;
    margin: 0 auto;
  }
  /* index */
  #index {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 80px 0 40px;
  }
  #index .logo {
    text-align: center;
    font-size: 0;
  }
  #index .logo .logo_pic {
    display: inline-flex;
    align-items: center;
  }
  #index .logo .logo_pic:hover span {
    color: #4285f4;
  }
  #index .logo .logo_icon {
    width: 200px;
  }
  #index .logo span {
    font-family: Fira Sans Extra Condensed;
    color: #2e3952;
    font-size: 50px;
    font-weight: 500;
    display: block;
    transition: color 0.4s ease;
  }
  #index .search-box {
    margin-top: 50px;
  }
  #index .advertise {
    margin-top: 50px;
  }
  #index .questions {
    display: flex;
    flex-wrap: wrap;
    margin-left: -30px;
    margin-top: 20px;
  }
  #index .questions a {
    display: inline-block;
    color: #4285f4;
    transition: color 0.4s ease;
    font-size: 18px;
    margin-left: 30px;
    margin-top: 20px;
  }
  #index .questions a:hover {
    color: #3668bc;
    text-decoration: underline;
  }
  /* content */
  #content {
    padding: 20px 0 100px;
    color: #212529;
  }
  #content .row {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
  }
  #content .main {
    width: 68%;
  }
  #content .article .category {
    font-size: 12px;
    font-weight: 500;
  }
  #content .article h1 {
    display: inline-block;
    font-weight: 700;
    font-size: 32px;
    margin-top: 10px;
  }
  #content .article .user {
    font-size: 14px;
    font-family: Fira Sans Extra Condensed;
  }
  #content .article .body {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid #f0f2f7;
  }
  #content .article .body p {
    font-size: 16px;
    margin-bottom: 1rem;
  }
  #content .article .body img {
    display: block;
    margin: 0 auto;
    max-width: 100%;
    object-fit: cover;
  }
  #content .article .body .advertise {
    margin: 1rem 0;
  }
  #content .article .body .see_go_btn {
    display: flex;
    justify-content: center;
    margin: 1rem 0;
  }
  #content .article .body .see_go_btn .btn {
    color: #fff;
    text-decoration: underline;
    background-color: #e95420;
    padding: 3px;
    border-radius: 2px;
    transition: all 0.4s ease;
  }
  #content .article .body .see_go_btn .btn:hover {
    transform: scale(1.04);
  }
  #content .article .body .card {
    margin-top: 50px;
  }
  #content .article .body .card .tit {
    color: #222;
    font-size: 18px;
    font-weight: 700;
    line-height: 1;
    display: block;
  }
  #content .article .body .answer_list .item {
    margin-top: 30px;
  }
  #content .article .body .answer_list .title {
    font-size: 20px;
    color: #155baf;
    font-weight: 700;
  }
  #content .article .body .answer_list .title:hover {
    color: #4285f4;
    text-decoration: underline;
  }
  #content .article .body .answer_list .title + p {
    margin-top: 0.5rem;
  }
  #content .heading {
    text-align: center;
    margin-bottom: 30px;
  }
  #content .heading h1 {
    color: #1e53a8;
    font-weight: 700;
    font-size: 40px;
  }
  #content .heading p {
    font-size: 16px;
  }
  #content .heading .advertise {
    margin-top: 20px;
  }
  #content .list li {
    padding: 20px 0;
    border-bottom: 1px solid #efefef;
    border-top: 1px solid #efefef;
  }
  #content .list li + li {
    border-top: 0;
  }
  #content .list a {
    color: #4285f4;
    transition: all 0.4s ease;
    font-size: 20px;
  }
  #content .list a:hover {
    color: #3668bc;
    text-decoration: underline;
  }
  #content .sidebar {
    width: 29%;
  }
  #content .sidebar .advertise:not(:first-child) {
    margin-top: 20px;
  }
  #content .sidebar .fixed {
    position: sticky;
    top: 10px;
  }
  #content .sidebar .item {
    margin-top: 30px;
  }
  #content .sidebar .item .heading {
    font-size: 18px;
    font-weight: 700;
    color: #4285f4;
    display: flex;
    align-items: center;
    padding-bottom: 15px;
    line-height: 1;
    border-bottom: 1px solid #4285f4;
  }
  #content .sidebar .item .heading .icon {
    margin-left: 5px;
  }
  #content .sidebar .item .list a {
    display: block;
    font-size: 15px;
    font-weight: 700;
    color: #2c66d4;
    transition: color 0.4s ease;
    margin-top: 15px;
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
  }
  #content .sidebar .item .list a:hover {
    color: #4285f4;
    text-decoration: underline;
  }
  @media all and (max-width: 1359px) {
    .container {
      max-width: 100%;
    }
    .navbar .nav_list a {
      font-size: 18px;
    }
    .navbar .nav_list a + a {
      margin-left: 20px;
    }
    .navbar .search-box .keyword {
      width: 65%;
    }
    .navbar .search-box {
      margin-left: 20px;
    }
  }
  @media all and (max-width: 1151px) {
    .container {
      max-width: 100%;
    }
    #index {
      padding: 60px 0 30px;
      min-height: 100%;
    }
    #index .logo span {
      font-size: 40px;
    }
    #index .logo .logo_icon {
      width: 180px;
    }
    #index .questions a {
      margin-left: 20px;
      font-size: 17px;
    }
    #index .questions {
      margin-left: -20px;
    }
    #content .main h1 {
      font-size: 30px;
    }
  }
  @media all and (max-width: 1000px) {
    .search-box .keyword {
      padding: 14px;
    }
    .search-box .search_btn {
      width: 24%;
      font-size: 16px;
    }
    .navbar .nav_list {
      position: absolute;
      display: none;
      width: 100%;
      top: calc(100% + 1px);
      background: #fff;
      z-index: 9999;
      padding: 30px 16px;
      left: 0;
      border-bottom: 1px solid #efefef;
    }
    header .menu {
      display: block;
      margin-left: auto;
    }
    .navbar .search-box .keyword {
      padding: 10px;
    }
    .search-box .search_btn {
      font-size: 14px;
    }
    .navbar .search-box {
      width: 60%;
    }
    .navbar .nav_logo {
      width: 110px;
    }
    .navbar .nav_list a {
      display: block;
    }
    .navbar .nav_list a + a {
      margin: 10px 0 0 0;
    }
    #index {
      padding: 50px 0 20px;
    }
    #index .search-box {
      margin-top: 40px;
    }
    #index .advertise {
      margin-top: 30px;
    }
    #index .questions a {
      font-size: 16px;
      margin-top: 15px;
      margin-left: 15px;
    }
    #index .questions {
      margin-left: -15px;
    }
    footer {
      padding: 15px 0;
    }
    #content .sidebar .item .list a {
      font-size: 14px;
      margin-top: 10px;
    }
    #content .heading h1 {
      font-size: 36px;
    }
    #content .list li {
      padding: 18px 0;
    }
    #content .list a {
      font-size: 18px;
    }
  }
  @media all and (max-width: 640px) {
    .search-box .keyword {
      padding: 10px;
      width: 60%;
    }
    .search-box .search_btn {
      width: 40%;
      font-size: 13px;
    }
    .navbar .search-box {
      display: none;
      width: 100%;
      top: calc(100% + 1px);
      position: absolute;
      left: 0;
      margin-left: 0;
    }
    .navbar .search-box .keyword,
    .navbar .search-box .search_btn {
      border-radius: 0;
    }
    .navbar .nav_list {
      padding: 20px 16px;
    }
    .search_mb {
      display: flex;
    }
    header .menu {
      margin-left: 10px;
    }
    #index {
      padding: 40px 0 20px;
    }
    #index .logo .logo_icon {
      width: 120px;
    }
    #index .logo span {
      font-size: 20px;
    }
    #index .search-box {
      margin-top: 30px;
    }
    #index .advertise {
      margin-top: 20px;
    }
    #index .questions a {
      font-size: 14px;
      margin-top: 5px;
      margin-left: 10px;
    }
    #index .questions {
      margin-left: -10px;
    }
    #content .main {
      width: 100%;
    }
    #content .sidebar {
      width: 100%;
      margin-top: 20px;
    }
    #content .sidebar .advertise {
      display: none;
    }
    #content .article .body p {
      margin-bottom: 0.8rem;
      font-size: 15px;
    }
    #content .article .body .advertise {
      margin: 0.8rem 0;
    }
    #content .article .body .answer_list .title {
      font-size: 18px;
    }
    #content .article .body .answer_list .title + p {
      margin-top: 0.3rem;
    }
    #content .article .body .answer_list .item {
      margin-top: 20px;
    }
    #content .sidebar .item .heading {
      font-size: 16px;
      padding-bottom: 10px;
    }
    #content .sidebar .item .heading .icon {
      margin-left: 3px;
      width: 12px;
      height: 12px;
    }
    #content .article .body .card {
      margin-top: 30px;
    }
    #content .article h1 {
      font-size: 26px;
    }
    #content .article .user {
      font-size: 13px;
    }
    #content .article .body {
      margin-top: 15px;
      padding-top: 15px;
    }
    #content .list li {
      padding: 15px 0;
    }
    #content .list a {
      font-size: 16px;
    }
    #content .heading h1 {
      font-size: 32px;
    }
    #content .heading .advertise {
      margin-top: 15px;
    }
    #content .heading p {
      font-size: 15px;
    }
  }