hugo-theme-hello-friend/source/css/menu.css

@define-mixin menu {
  position: absolute;
  background: var(--light-header);
  box-shadow: var(--shadow);
  margin: 0;
  padding: 5px;
  list-style: none;
  border-radius: 5px;
  z-index: 99;

  .dark-theme & {
    background: var(--dark-background-secondary);
  }
}

.menu {
  --shadow-color: rgba(0, 0, 0, .12);
  --shadow: 0 8px 20px var(--shadow-color);

  border-right: 1px solid;
  margin-right: 18px;
  padding-right: 24px;
  font-weight: 600;

  @media (--phone) {
    @mixin menu;
    border: none;
    top: 50px;
    right: 10px;
  }

  a {
    text-decoration: none;
  }

  &__inner {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    flex-wrap: wrap;
    list-style: none;
    margin: 0;
    padding: 0;

    &--desktop {
      @media (--phone) {
        display: none;
      }
    }

    &--mobile {
      display: none;

      @media (--phone) {
        display: block;
      }
    }

    li {
      text-align: left;
      flex: 0 0 auto;

      &:not(:first-of-type) {
        margin-left: 20px;
      }
    }

    @media (--phone) {
      flex-direction: column;
      align-items: flex-start;
      padding: 0;

      li {
        margin-left: 0 !important;
        padding: 10px;
      }
    }
  }

  &__sub-inner {
    position: relative;
    list-style: none;
    padding: 0;
    margin: 0;

    &:not(:only-child) {
      margin-left: 20px;
    }

    &-more {
      @mixin menu;
      top: 35px;
      left: 0;

      &-trigger {
        display: inline-flex;
        align-items: center;
        user-select: none;
        cursor: pointer;

        &-icon {
          display: inline-flex;
          align-items: center;
          margin-left: 3px;
          transform: rotate(90deg);
          line-height: 1;

          @mixin greater-icon 5px;
        }
      }

      li {
        .menu__inner & {
          margin-left: 0;
          white-space: nowrap;

          &:hover {
            background: rgba(0, 0, 0, 0.05);
            border-radius: 3px;
            cursor: pointer;

            .dark-theme & {
              background: rgba(0, 0, 0, 0.15);
            }
          }
        }
      }

      li a {
        width: 100%;
        display: inline-block;
        padding: 10px;
      }
    }
  }

  &-trigger {
    width: 24px;
    height: 24px;
    fill: currentColor;
    margin-left: 10px;
    cursor: pointer;
  }
}