@media only screen and (max-width : 650px) {
  .first-section__heading {
    font-size: 26px;
    line-height: 34px;
    padding-top: 40px;
  }

  .first-section__wrapper {
    flex-wrap: wrap;
    margin-top: 20px;
  }

  .first-section__item {
    margin-top: 25px;
    max-width: 100%;
    flex: 1 1 200px;
  }

  .main-form {
    padding: 20px;
    margin-top: 40px;
  }

  .second-section__heading {
    font-size: 26px;
  }

  .second-section-text   {
    font-size: 16px;
  }

  .second-section-item {
    min-height: 175px;
  }

  .circle {
    height: 80px;
    width: 80px;
    background-size: cover;
    margin-top: -65px;
  }
  .third-section {
    padding-bottom: 10px;
  }

  .third-section__item {
    margin-top: 90px;
    padding-top: 25px;
    min-height: 100px;
  }

  .third-section__title {
    font-size: 18px;
  }

  .third-section__text {
    font-size: 14px;
    line-height: 22px;
  }

  .four-section {
    padding-bottom: 50px;
    -webkit-background-size: cover;
    background-size: cover;
  }

  .four-section__form {
    max-width: 450px;
    position: relative;
  }

  .four-section__heading {
    margin-top: 90px;
    font-size: 26px;
  }

  .four-section__post-heading {
    font-size: 14px;
  }

  .four-section__email {
    width: 100%;
  }

  .four-section__name {
    width: 100%;
    float: none;
  }

  .four-section__submit {
    position: absolute;
    bottom: 5px;
  }
  .four-section__textarea {
    height: 220px;
  }

  .tnx-pop {
    max-width: 550px;
    min-height: 360px;
    margin: auto;
    padding: 15px 10px 20px;
  }

  .tnx-pop__heading {
    font-size: 20px;
  }

  .tnx-pop__text {
    font-size: 16px;
  }
}

@media only screen and (max-width : 450px) {
  .first-section__item {
    flex: 1 1 143px;
  }
}