.block1 {
  position: relative;
  display: flex;
  height: 100vh;
  width: 100vw;
  min-height: 500px;

  overflow: hidden;

  justify-content: center;
  align-items: center;

  font-family: 'Oswald', 'Raleway', 'Helvetica Neue', Helvetica, Arial,
    sans-serif;
}

.b1__picture {
  display: flex;

  justify-content: center;
  align-items: center;
}
.b1__img {
  position: absolute;
  top: 0;
  min-height: 100%;
  min-width: 100vw;
  z-index: -1;
}

.b1__mobile-text {
  display: flex;
  position: absolute;

  height: 100%;
  width: 100vw;

  justify-content: center;
  align-items: center;
  flex-direction: column;

  color: white;

  font-weight: 100;

  background-color: rgba(0, 0, 0, 0.3);
}

.b1__mobile-text-title {
  /* minFont + (MaxFont - MinFont) * (100VW - minSize) / (maxSize - minSize) */
  font-size: calc(24px + (72 - 24) * (100vw - 400px) / (1600 - 400));

  letter-spacing: 0.6rem;

  text-transform: uppercase;
  font-weight: 100;
}
.b1__mobile-text-description {
  font-size: calc(16px + (20 - 16) * (100vw - 400px) / (1600 - 400));
  letter-spacing: 0.1rem;
}

.b1__mobile-social {
  display: none;
}

@media (max-width: 768px) {
  .b1__mobile-text {
    justify-content: flex-start;
  }
  .b1__mobile-text-title {
    padding-top: 6rem;
  }

  .b1__mobile-social {
    position: absolute;
    display: flex;

    bottom: 0;

    justify-content: center;
    align-items: flex-end;

    padding-bottom: 4rem;
  }

  .b1__box {
    cursor: pointer;
    margin: 0 0.5rem;
  }

  .b1__box-img {
    height: 2em;
  }
}