.button_bl {
  background-color: #222222;
  transition: background-color 0.3s;
  width: fit-content;
  a {
    display: block;
    color: #fff;
    width: 100%;
    padding: 20px calc(100 / 1366 * 100vw);
    @media screen and (min-width: 1366px) {
      padding: 20px 100px;
    }
  }
  &:hover {
    background-color: #616161;
  }
  &.mc {
    margin: 0 auto;
  }
  &.ml {
    margin-left: auto;
  }
  &.mr {
    margin-right: auto;
  }
}

@media screen and (max-width: 768px) {
  .button_bl {
    width: 60%;
    a {
      padding: 15px 50px;
      font-size: 24px;
      text-align: center;
    }
  }
}

@media screen and (max-width: 480px) {
  .button_bl {
    a {
      font-size: 14px;
    }
  }
}