.header { position: sticky; top: 0; left: 0; width: 100%; height: 5rem; background-color: var(--color-white); box-shadow: var(--header-shadow),var(--shadow-inset); margin-bottom: -5rem; z-index: 10; } .header.is-open { box-shadow: unset; } .header.is-open .header__mobile { display: block; position: fixed; } .header__section { position: relative; display: flex; align-items: center; justify-content: space-between; height: 100%; } .header__mobile { display: none; width: 100%; height: calc(100% - 4.75rem); background-color: var(--color-white); z-index: 20; } .header__button { position: relative; border: 0; background: transparent; padding: 2rem 2rem; } .header__button > span{ display: block; position: absolute; height: 0.125rem; width: 1.625rem; background: var(--color-black); opacity: 1; left: calc(50% - 0.8125rem); border-radius: 10rem; transform: rotate(0deg); transition: all 0.3s ease; } .header__button > span:nth-child(1) { top: calc(50% - 0.4375rem); } .header__button > span:nth-child(2) { top: calc(50% - 0.0625rem); } .header__button > span:nth-child(3) { top: calc(50% - 0.0625rem); } .header__button > span:nth-child(4) { top: calc(50% + 0.3125rem); } .header__button.is-active > span:nth-child(1), .header__button.is-active > span:nth-child(4) { width: 0%; left: 50%; } .header__button.is-active > span:nth-child(2) { transform: rotate(45deg); } .header__button.is-active > span:nth-child(3) { transform: rotate(-45deg); }