.about {
  position: relative;
  padding-top: 4.17vw;
  padding-bottom: 4.27vw;
  background-color: #fff;
}

.about .wrapper {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
}

.about .left {
  width: 53.23vw;
}

.about .left .title {
  font-weight: 700;
  font-size: 2.29vw;
  line-height: 1;
}

.about .left .desc {
  margin-top: 1.3vw;
  font-size: 1.15vw;
  line-height: 1;
}

.about .left .content {
  margin-top: 2.92vw;
  text-align: justify;
  line-height: 2;
  font-size: .83vw;
}

.about .left .content p {
  margin-bottom: 1.56vw;
}

.about .left .content p:last-child {
  margin-bottom: 0;
}

.about .left .logo {
  position: absolute;
  bottom: calc(4.27vw + .83vw);
}

.about .left .logo img {
  width: 31.25vw;
}

.about .left .logo .text {
  display: flex;
  align-items: baseline;
  position: absolute;
  bottom: -0.89vw;
  line-height: 1;
  font-style: italic;
}

.about .left .logo .text .since {
  font-family: Arial;
  font-size: 1.98vw;
  font-weight: 700;
  text-transform: uppercase;
}

.about .left .logo .text .year {
  font-family: Arial;
  font-size: 3.65vw;
  font-weight: 700;
  text-transform: uppercase;
  color: #2D77D9;
  line-height: 1;
  margin-left: .21vw;
}

.about .right {
  width: 29.79vw;
}

.about .right img {
  width: 100%;
}

.certification {
  position: relative;
  height: 34.38vw;
  background-color: #f7f9fd;
  padding-top: 4.48vw;
}

.certification .title {
  font-size: .83vw;
  line-height: 2;
  width: 49vw;
}

.certification .title span {
  font-weight: 700;
}

.certification .list {
  display: grid;
  margin-top: 5.94vw;
  grid-template-columns: repeat(6, 1fr);
  gap: 0 2.08vw;
}

.certification .list .item {
  border-top: 2px solid #333;
  padding-top: 1.25vw;
  padding-bottom: 1.41vw;
  line-height: 1;
  border-bottom: 2px solid #d7dfe2;
}

.certification .list .item .name {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  font-size: 3.54vw;
  font-family: Arial;
  font-weight: 700;
}

.certification .list .item .name img {
  width: 1.25vw;
  transform: translateY(.42vw);
}

.certification .list .item .desc {
  font-size: .83vw;
  margin-top: .83vw;
}

.certification .logo {
  position: absolute;
  width: 31.25vw;
  right: 5.73vw;
  bottom: 3.33vw;
}

.slogan {
  position: relative;
  display: flex;
  justify-content: space-between;
  height: 31.56vw;
  margin-top: -6.15vw;
}

.slogan .left {
  background-color: #fff;
}

.slogan .left img {
  width: 64.43vw;
  height: 100%;
  object-fit: cover;
}

.slogan .right {
  position: absolute;
  right: 0;
  bottom: 0;
  width: 50vw;
  height: 25.42vw;
  background-color: #fff;
  padding: 3.85vw 6vw 0 3.96vw;
}

.slogan .right .title {
  line-height: 1;
  font-size: 2.29vw;
  font-weight: 700;
}

.slogan .right .content {
  margin-top: 2.76vw;
  text-align: justify;
  line-height: 2;
}

.slogan .right .content p {
  font-size: .83vw;
  margin-bottom: 1.56vw;
}

.production {
  position: relative;
  z-index: 1;
  padding-top: 3.59vw;
  padding-bottom: 5.52vw;
  background-color: #fff;
}

.production .container>.title {
  font-size: 2.29vw;
  font-weight: 700;
  line-height: 1;
  margin-bottom: 3.54vw;
}

.production .list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: repeat(2, 1fr);
  gap: 1.46vw;
  height: 35.21vw;
}

.production .list .item {
  position: relative;
  min-height: 0;
  overflow: hidden;
  cursor: pointer;
}

.production .list .item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.production .list .item .info {
  position: absolute;
  inset: 0;
  background-color: rgba(0, 0, 0, .6);
  transition: background-color 0.35s ease;
}

.production .list .item:hover img {
  transform: scale(1.08);
}

.production .list .item:hover .info {
  background-color: rgba(0, 0, 0, .25);
}

.production .list .item .info .content {
  color: #fff;
  display: flex;
  flex-direction: column;
  align-items: center;
  left: 50%;
  transform: translateX(-50%);
  position: absolute;
  bottom: 6.41vw;
  line-height: 1;
}

.production .list .item .info .content .title {
  font-size: 1.67vw;
}

.production .list .item .info .content .line {
  margin-top: 1.09vw;
  height: 3px;
  width: 1.61vw;
  background-color: #2D77D9;
}

.production .list .item .info .content .en {
  margin-top: .78vw;
  font-size: .83vw;
}


.production .list .item-1 {
  grid-column: 1;
  grid-row: 1 / span 2;
}

.production .list .item-2 {
  grid-column: 2;
  grid-row: 1;
}

.production .list .item-3 {
  grid-column: 2;
  grid-row: 2;
}

.production .list .item-4 {
  grid-column: 3;
  grid-row: 1 / span 2;
}

.brand {
  position: relative;
  z-index: 1;
  padding-top: 4.9vw;
  /* height: 35.68vw; */
  background: url(../images/about-brand-bg.jpg) 0 bottom/cover fixed;
}

.brand .title {
  line-height: 1;
  font-weight: 700;
  font-size: 2.29vw;
}

.brand .list {
  margin-top: 5vw;
  display: flex;
  gap: 1.61vw;
  padding-bottom: 5vw;
  justify-content: center;
  flex-wrap: wrap;
}

.brand .list .item {
  width: calc((100% - 3 * 1.61vw) / 4);
  display: flex;
  flex-direction: column;
  align-items: center;
  border-radius: .42vw;
  box-shadow: 0px 0px 30px 0px rgba(2, 54, 86, 0.1);
  background-color: #fff;
  height: 13.23vw;
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.4s ease;
}

.brand .list .item:hover {
  transform: translateY(-0.52vw);
  box-shadow: 0 1.04vw 2.08vw rgba(2, 54, 86, 0.18);
}

.brand .list .item .img-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  flex: 1;
  overflow: hidden;
}

.brand .list .item .img-wrap img {
  width: 11.77vw;
  transform: translateY(35%);
  transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

.brand .list .item:hover .img-wrap img {
  transform: translateY(35%) scale(1.05);
}

.brand .list .item .brand-name {
  margin: 0 auto;
  width: 17.5vw;
  border-top: 2px solid #edf8fe;
  line-height: 1;
  padding-top: .89vw;
  padding-bottom: 1.25vw;
  display: flex;
  justify-content: center;
  font-size: .94vw;
  transition: color 0.35s ease;
}

.brand .list .item:hover .brand-name {
  color: #2D77D9;
}

.course {
  position: relative;
  z-index: 1;
  background-color: #fff;
  overflow-x: hidden;
}

.course .header {
  line-height: 1;
  padding-top: 4.01vw;
  padding-bottom: 3.28vw;
}

.course .header .title {
  font-size: 2.29vw;
  font-weight: 700;
}

.course .header .desc {
  margin-top: 1.67vw;
  font-size: 1.15vw;
}

.course .course-banner-wrap {
  position: relative;
  height: 44.9vw;
  --course-axis-shift: 3.13vw;
  background: var(--bg-image) 0 0/cover fixed;
  overflow: hidden;
}

.course-swiper-viewport {
  position: relative;
  height: 100%;
  --course-viewport-pad-x: 4.69vw;
  padding: 0 var(--course-viewport-pad-x);
  overflow: hidden;
  box-sizing: border-box;
}

.course-timeline-line {
  position: absolute;
  top: calc(50% - var(--course-axis-shift));
  left: calc(var(--course-viewport-pad-x) * -1);
  right: calc(var(--course-viewport-pad-x) * -1);
  height: 1px;
  background: rgba(255, 255, 255, 0.2);
  z-index: 1;
  pointer-events: none;
}

.course-swiper {
  width: 100%;
  height: 100%;
  overflow: hidden;
}

.course-swiper .swiper-slide {
  height: auto;
  overflow: visible;
  box-sizing: border-box;
  flex-shrink: 0;
}

@media (min-width: 768px) and (max-width: 1020px) {
  .course-swiper .swiper-slide {
    width: 50%;
  }
}

@media (min-width: 1021px) and (max-width: 1199px) {
  .course-swiper .swiper-slide {
    width: 33.333333%;
  }
}

@media (min-width: 1200px) {
  .course-swiper .swiper-slide {
    width: 20%;
  }
}

.timeline-item {
  position: relative;
  height: 44.9vw;
}

.timeline-item .panel {
  position: absolute;
  left: 0;
  right: 0;
  display: flex;
  align-items: stretch;
  box-sizing: border-box;
}

.timeline-item.is-bottom .panel {
  top: calc(50% - var(--course-axis-shift, 3.13vw));
}

.timeline-item.is-top .panel {
  bottom: calc(50% + var(--course-axis-shift, 3.13vw));
}

.timeline-item .v-line {
  position: relative;
  width: 2.6vw;
  flex-shrink: 0;
  background: linear-gradient(to right, transparent calc(50% - 0.5px), rgba(255, 255, 255, 0.2) calc(50% - 0.5px), rgba(255, 255, 255, 0.2) calc(50% + 0.5px), transparent calc(50% + 0.5px));
}

.course-swiper .swiper-slide:first-child .timeline-item .v-line {
  margin-left: 0.2vw;
}

.course-swiper .swiper-slide:last-child .timeline-item .v-line {
  margin-right: 0.2vw;
}

.timeline-item .node {
  position: absolute;
  left: 50%;
  width: .83vw;
  height: .83vw;
  border-radius: 50%;
  background: rgba(255, 255, 255, 1);
  z-index: 3;
  transition: background-color 0.45s ease;
}

.timeline-item .node::after {
  content: '';
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%) scale(1);
  width: 2.03vw;
  height: 2.03vw;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.2);
  z-index: 3;
  transition: transform 0.55s cubic-bezier(0.34, 1.45, 0.64, 1), background 0.45s ease;
}

.timeline-item.is-bottom .node {
  top: 0;
  transform: translate(-50%, -50%);
}

.timeline-item.is-top .node {
  bottom: 0;
  transform: translate(-50%, 50%);
}

.course-swiper .swiper-slide:hover .timeline-item .node {
  background-color: #2d77d9;
}

.course-swiper .swiper-slide:hover .timeline-item .node::after {
  background: rgba(45, 119, 217, 0.2);
  transform: translate(-50%, -50%) scale(1.18);
}

.timeline-item .card {
  flex: 1;
  min-width: 0;
  padding-left: 0.36vw;
  padding-right: 1.19vw;
  color: #fff;
  line-height: 1;
}

.timeline-item.is-bottom .card {
  padding-top: 2.6vw;
}

.timeline-item.is-top .card {
  padding-bottom: 3.18vw;
}

.timeline-item .card .year {
  font-size: 3.54vw;
  font-weight: 700;
  line-height: 1;
  transform-origin: left center;
  transition: opacity 0.45s ease, transform 0.45s cubic-bezier(0.22, 1, 0.36, 1);
}

.timeline-item .card .year-line {
  width: 1.72vw;
  height: 3px;
  background-color: #fff;
  margin-top: 1.04vw;
  transition: opacity 0.45s ease, transform 0.45s cubic-bezier(0.22, 1, 0.36, 1), width 0.5s cubic-bezier(0.22, 1, 0.36, 1), background-color 0.45s ease;
}

.timeline-item .card .desc {
  margin-top: .78vw;
  font-size: .83vw;
  line-height: 1.75;
  text-align: justify;
  display: -webkit-box;
  -webkit-line-clamp: 5;
  -webkit-box-orient: vertical;
  overflow: hidden;
  transition: opacity 0.45s ease, transform 0.45s cubic-bezier(0.22, 1, 0.36, 1);
}

@media (hover: hover) {
  .course-swiper .swiper-slide:hover .timeline-item .card .year {
    transform: scale(1.04);
  }

  .course-swiper .swiper-slide:hover .timeline-item .card .year-line {
    width: 2.8vw;
    background-color: #2d77d9;
    transition-delay: 0.06s;
  }

  .course-swiper .swiper-slide:hover .timeline-item .card .desc {
    transform: translateY(-0.28vw);
    transition-delay: 0.12s;
  }
}

.course-nav {
  position: absolute;
  bottom: 4.06vw;
  left: 0;
  right: 0;
  width: fit-content;
  margin-left: auto;
  margin-right: auto;
  display: flex;
  z-index: 5;
}

.course-swiper-prev,
.course-swiper-next {
  width: 9.38vw;
  height: 2.6vw;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  transition: all 0.3s ease;
}

.course-swiper-prev {
  background-color: #fff;
}

.course-swiper-next {
  margin-left: .73vw;
  background-color: #fff;
}

.course-swiper-prev:not(.swiper-button-disabled):hover,
.course-swiper-next:not(.swiper-button-disabled):hover {
  background-color: #2D77D9;
}

.course-swiper-prev:not(.swiper-button-disabled):hover::after,
.course-swiper-next:not(.swiper-button-disabled):hover::after {
  background-color: #fff;
}

.course-swiper-prev img,
.course-swiper-next img {
  display: none;
}

.course-swiper-prev::after,
.course-swiper-next::after {
  content: '';
  width: .63vw;
  aspect-ratio: 12 / 20;
  -webkit-mask: url(../images/arrow-right-icon.svg) no-repeat center / contain;
  mask: url(../images/arrow-right-icon.svg) no-repeat center / contain;
  transition: all .3s;
}

.course-swiper-prev::after {
  background-color: #333;
  transform: rotate(180deg);
}

.course-swiper-next::after {
  background-color: #333;
}

.course-swiper-prev.swiper-button-disabled,
.course-swiper-next.swiper-button-disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

footer {
  position: relative;
  z-index: 1;
}

/* 企业简介 — 移动端适配（375 设计稿，变量见 common.css） */
@media screen and (max-width: 1020px) {
  .about {
    padding-top: var(--m-section-py);
    padding-bottom: var(--m-section-py);
  }

  .about .wrapper {
    flex-direction: column;
    gap: var(--m-gap-block);
  }

  .about .left,
  .about .right {
    width: 100%;
  }

  .about .left .title {
    font-size: var(--m-font-h1);
  }

  .about .left .desc {
    margin-top: var(--m-space-xs);
    font-size: var(--m-font-h3);
    line-height: 1.5;
  }

  .about .left .content {
    margin-top: var(--m-space-md);
    font-size: var(--m-font-body);
    line-height: 1.85;
  }

  .about .left .content p {
    margin-bottom: var(--m-space-md);
  }

  .about .left .logo {
    position: relative;
    bottom: auto;
    margin-top: var(--m-space-lg);
    width: 74.667vw;
    max-width: 100%;
  }

  .about .left .logo img {
    width: 100%;
  }

  .about .left .logo .text {
    bottom: -2.133vw;
  }

  .about .left .logo .text .since {
    font-size: var(--m-font-h2);
  }

  .about .left .logo .text .year {
    font-size: var(--m-font-accent);
    margin-left: var(--m-space-3xs);
  }

  .certification {
    height: auto;
    padding-top: var(--m-section-py);
    padding-bottom: var(--m-section-py);
  }

  .certification .title {
    width: 100%;
    font-size: var(--m-font-body);
    line-height: 1.85;
  }

  .certification .list {
    margin-top: var(--m-gap-block);
    grid-template-columns: repeat(2, 1fr);
    gap: var(--m-space-md) var(--m-space-sm);
  }

  .certification .list .item {
    padding-top: var(--m-space-sm);
    padding-bottom: var(--m-space-sm);
    border-bottom: none;
  }

  .certification .list .item .name {
    font-size: var(--m-font-display);
  }

  .certification .list .item .name img {
    width: var(--m-icon-md);
    transform: translateY(0.8vw);
  }

  .certification .list .item .desc {
    margin-top: var(--m-space-xs);
    font-size: var(--m-font-body);
    line-height: 1.5;
  }

  .certification .logo {
    position: relative;
    right: auto;
    bottom: auto;
    display: block;
    width: 74.667vw;
    max-width: 100%;
    margin: var(--m-gap-block) auto 0;
  }

  .slogan {
    flex-direction: column;
    height: auto;
    margin-top: 0;
  }

  .slogan .left {
    width: 100%;
  }

  .slogan .left img {
    width: 100%;
    height: auto;
    display: block;
  }

  .slogan .right {
    position: relative;
    right: auto;
    bottom: auto;
    width: 100%;
    height: auto;
    padding: var(--m-section-py) var(--m-space-md);
    box-sizing: border-box;
  }

  .slogan .right .title {
    font-size: var(--m-font-h1);
    line-height: 1.3;
  }

  .slogan .right .content {
    margin-top: var(--m-space-md);
  }

  .slogan .right .content p {
    font-size: var(--m-font-body);
    line-height: 1.85;
    margin-bottom: var(--m-space-md);
  }

  .production {
    padding-top: var(--m-section-py);
    padding-bottom: var(--m-section-py);
  }

  .production .container > .title {
    font-size: var(--m-font-h1);
    margin-bottom: var(--m-gap-block);
  }

  .production .list {
    grid-template-columns: 1fr;
    grid-template-rows: auto;
    gap: var(--m-space-md);
    height: auto;
  }

  .production .list .item-1,
  .production .list .item-2,
  .production .list .item-3,
  .production .list .item-4 {
    grid-column: 1;
    grid-row: auto;
    height: 56vw;
    min-height: 12.5rem;
  }

  .production .list .item .info .content {
    bottom: var(--m-space-lg);
  }

  .production .list .item .info .content .title {
    font-size: var(--m-font-h2);
  }

  .production .list .item .info .content .line {
    margin-top: var(--m-space-xs);
    width: 6.4vw;
    height: 2px;
  }

  .production .list .item .info .content .en {
    margin-top: var(--m-space-2xs);
    font-size: var(--m-font-body);
  }

  .brand {
    height: auto;
    padding-top: var(--m-section-py);
    padding-bottom: var(--m-section-py);
  }

  .brand .title {
    font-size: var(--m-font-h1);
  }

  .brand .list {
    margin-top: var(--m-gap-block);
    /* grid-template-columns: repeat(2, 1fr); */
    gap: var(--m-space-md);
  }

  .brand .list .item {
    width: 100%;
    height: auto;
    min-height: 34.667vw;
    border-radius: var(--m-space-2xs);
  }

  .brand .list .item .img-wrap img {
    width: 28vw;
    transform: translateY(20%);
  }

  .brand .list .item:hover .img-wrap img {
    transform: translateY(20%) scale(1.05);
  }

  .brand .list .item .brand-name {
    width: calc(100% - var(--m-space-md));
    padding-top: var(--m-space-sm);
    padding-bottom: var(--m-space-sm);
    font-size: var(--m-font-body);
  }

  .course .header {
    padding-top: var(--m-section-py);
    padding-bottom: var(--m-gap-block);
  }

  .course .header .title {
    font-size: var(--m-font-h1);
  }

  .course .header .desc {
    margin-top: var(--m-space-sm);
    font-size: var(--m-font-h3);
    line-height: 1.5;
  }
}

/* 发展历程 — 平板（768~1020，与全站 mobile 断点重叠区间） */
@media screen and (min-width: 768px) and (max-width: 1020px) {
  .course .course-banner-wrap {
    height: auto;
    --course-axis-shift: 4vw;
    padding-bottom: 14vw;
    background-position: center;
  }

  .course-swiper-viewport {
    --course-viewport-pad-x: 3.2vw;
    height: 58vw;
    min-height: 22rem;
    padding: 0 var(--course-viewport-pad-x);
  }

  .timeline-item {
    height: 100%;
    min-height: 22rem;
  }

  .timeline-item .v-line {
    width: 4vw;
  }

  .timeline-item .node {
    width: 1.25vw;
    height: 1.25vw;
  }

  .timeline-item .node::after {
    width: 3vw;
    height: 3vw;
  }

  .timeline-item .card {
    padding-left: 0.8vw;
    padding-right: 1.6vw;
  }

  .timeline-item.is-bottom .card {
    padding-top: 2vw;
  }

  .timeline-item.is-top .card {
    padding-bottom: 2.4vw;
  }

  .timeline-item .card .year {
    font-size: 4.8vw;
  }

  .timeline-item .card .year-line {
    width: 2.4vw;
    margin-top: 1.2vw;
  }

  .timeline-item .card .desc {
    margin-top: 1vw;
    font-size: 1.6vw;
    line-height: 1.7;
    -webkit-line-clamp: 7;
  }

  @media (hover: hover) {
    .course-swiper .swiper-slide:hover .timeline-item .card .year-line {
      width: 4vw;
    }

    .course-swiper .swiper-slide:hover .timeline-item .card .desc {
      transform: translateY(-0.5vw);
    }
  }

  .course-nav {
    bottom: 3.2vw;
  }

  .course-swiper-prev,
  .course-swiper-next {
    width: 22vw;
    height: 6.4vw;
  }

  .course-swiper-next {
    margin-left: 1.6vw;
  }

  .course-swiper-prev::after,
  .course-swiper-next::after {
    width: 1.2vw;
  }
}

/* 发展历程 — 手机（<768） */
@media screen and (max-width: 767px) {
  .course .header {
    padding-top: var(--m-section-py);
    padding-bottom: var(--m-gap-block);
  }

  .course .header .title {
    font-size: var(--m-font-h1);
  }

  .course .header .desc {
    margin-top: var(--m-space-sm);
    font-size: var(--m-font-h3);
    line-height: 1.5;
  }

  .course .course-banner-wrap {
    height: auto;
    --course-axis-shift: 6.4vw;
    min-height: clamp(30rem, 128vw, 45rem);
  }

  .course-swiper-viewport {
    --course-viewport-pad-x: var(--m-space-md);
    height: clamp(30rem, 128vw, 40rem);
    padding: 0 var(--course-viewport-pad-x);
  }

  .timeline-item {
    height: 100%;
  }

  .timeline-item .v-line {
    width: 10.667vw;
  }

  .course-swiper .swiper-slide:last-child .timeline-item .v-line {
    margin-right: 0.8vw;
  }

  .timeline-item .node {
    width: 3.2vw;
    height: 3.2vw;
  }

  .timeline-item .node::after {
    width: 8vw;
    height: 8vw;
  }

  .timeline-item .card {
    padding-left: var(--m-space-2xs);
    padding-right: var(--m-space-sm);
  }

  .timeline-item.is-bottom .card {
    padding-top: var(--m-space-lg);
  }

  .timeline-item.is-top .card {
    padding-bottom: var(--m-space-lg);
  }

  .timeline-item .card .year {
    font-size: var(--m-font-accent);
  }

  .timeline-item .card .year-line {
    width: 6.4vw;
    margin-top: var(--m-space-xs);
    height: 2px;
  }

  .timeline-item .card .desc {
    margin-top: var(--m-space-2xs);
    font-size: var(--m-font-body);
    line-height: 1.75;
    -webkit-line-clamp: 5;
  }

  .course-nav {
    bottom: var(--m-space-lg);
  }

  .course-swiper-prev,
  .course-swiper-next {
    width: var(--m-btn-w);
    height: var(--m-btn-h);
  }

  .course-swiper-next {
    margin-left: var(--m-space-sm);
  }

  .course-swiper-prev::after,
  .course-swiper-next::after {
    width: var(--m-icon-arrow);
  }
}