body {
  display: flex;
  flex-direction: column;
  margin: 0;
}

header {
  background-color: #f0f0f0;
  padding: 20px;
}

nav {
  background-color: #eee;
  padding: 10px;
}

nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
}

nav li {
  margin-right: 20px;
}

main {
  flex: 1;
  padding: 20px;
}

footer {
  background-color: #333;
  color: #fff;
  padding: 10px;
  text-align: center;
}

/* ?????????????? */
image-slider {
  display: block; /* ???????????????? */
  width: 80%;
  margin: 20px auto;
}

image-slider .slider {
  position: relative;
  width: 100%;
  overflow: hidden;
}

image-slider .slider img {
  width: 100%;
  display: none;
}

image-slider .slider img.active {
  display: block;
}

image-slider .thumbnails {
  display: flex;
  margin-top: 10px;
}

image-slider .thumbnails img {
  width: 100px;
  height: 100px;
  margin-right: 10px;
  cursor: pointer;
}

/* header menu  */
.button {
  -webkit-appearance: none;
     -moz-appearance: none;
          appearance: none;
  color: #fff;
  background-color: #2fa0f6;
  min-width: 120px;
  padding: 0.5rem 1rem;
  border-radius: 5px;
  text-align: center;
}
@media (max-width: 629px) {
  .button {
  margin-right: 2.5rem;     
    }
}

.brand {
  font-weight: bold;
  font-size: 20px; }

.site-header {
  position: relative;
  background-color: #def7ff; }

.site-header__wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem; }
  @media (min-width: 630px) {
    .site-header__wrapper {
      justify-content: initial; }
  }
@media (min-width: 630px) {
  .site-header__middle {
    margin-left: auto; }
}

@media (max-width: 629px) {
  .site-header__end {
    padding-right: 4rem; }
}

@media (min-width: 630px) {
  .nav__wrapper {
    display: flex; }
}

@media (max-width: 629px) {
  .nav__wrapper {
    position: absolute;
    top: 100%;
    right: 0;
    left: 0;
    z-index: -1;
    background-color: #d9f0f7;
    visibility: hidden;
    opacity: 0;
    transform: translateY(-100%);
    transition: transform 0.3s ease-out, opacity 0.3s ease-out; }

    .nav__wrapper.active {
      visibility: visible;
      opacity: 1;
      transform: translateY(0); }
}

li.nav__item {
    list-style-type: none;
}
.nav__item a {
  display: block;
  padding: 1rem;
}

.nav__toggle {
  display: none; }
  @media (max-width: 629px) {
    .nav__toggle {
      display: block;
      position: absolute;
      right: 1rem;
      top: 1rem; }
  }