header {
  height: 210px;
  background-color: #3a5151;
}
header nav {
  position: static;
}

.tissus-intro h1 {
  background-color: #fce4da;
  color: #3a5151;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
  margin: 0 auto;
  padding: 80px 0px;
  font-size: 26px;
}

.tissus-intro div {
  width: 80%;
  margin: auto;
}
.tissus-intro div > img {
  object-fit: cover;
  width: 100%;
}