ant-design/style/components/carousel/slick-theme.less

.ant-carousel {

  /* Arrows */

  .slick-prev,
  .slick-next {
    position: absolute;
    display: block;
    height: 20px;
    width: 20px;
    line-height: 0px;
    font-size: 0px;
    cursor: pointer;
    background: transparent;
    color: transparent;
    top: 50%;
    margin-top: -10px;
    padding: 0;
    border: none;
    outline: none;
    &:hover, &:focus {
      outline: none;
      background: transparent;
      color: transparent;
      &:before {
        opacity: 1;
      }
    }
    &.slick-disabled:before {
      opacity: 0.25;
    }
  }

  .slick-prev {
    left: -25px;
    &:before {
      content: "←";
    }
  }

  .slick-next {
    right: -25px;
    &:before {
      content: "→";
    }
  }

  /* Dots */

  .slick-slider {
    padding-bottom: 45px;
  }

  .slick-dots {
    position: absolute;
    bottom: 0px;
    list-style: none;
    display: block;
    text-align: center;
    padding: 0;
    width: 100%;
    li {
      position: relative;
      display: inline-block;
      height: 20px;
      width: 20px;
      margin: 0 5px;
      padding: 0;
      cursor: pointer;
      button {
        border: 0;
        background: transparent;
        display: block;
        height: 20px;
        width: 20px;
        outline: none;
        line-height: 0px;
        font-size: 0px;
        color: transparent;
        padding: 5px;
        cursor: pointer;
        &:hover, &:focus {
          outline: none;
          &:before {
            opacity: 1;
          }
        }
        &:before {
          position: absolute;
          top: 0;
          left: 0;
          content: "•";
          width: 20px;
          height: 20px;
          font-size: 18px;
          font-family: arial, sans-serif;
          line-height: 20px;
          text-align: center;
          color: gray;
          opacity: 0.25;
          -webkit-font-smoothing: antialiased;
          -moz-osx-font-smoothing: grayscale;
        }
      }
      &.slick-active button:before {
        color: black;
        opacity: 0.75;
      }
    }
  }
}

.ant-carousel-vertical {

  .slick-slider {
    padding-bottom: 0;
  }

  .slick-dots {
    width: 20px;
    bottom: auto;
    right: -35px;
    top: 0;
  }
}