grid.css

.container {
    margin-right: auto;
    margin-left: auto;
    padding-right: 15px;
    padding-left: 15px; 
    position: relative;
  }
  
  @media (min-width: 576px) {
    .container {
      padding-right: 15px;
      padding-left: 15px;
    }
  }
  
  @media (min-width: 768px) {
    .container {
      padding-right: 15px;
      padding-left: 15px;
    }
  }
  
  @media (min-width: 992px) {
    .container {
      padding-right: 15px;
      padding-left: 15px;
    }
  }
  
  @media (min-width: 1200px) {
    .container {
      padding-right: 15px;
      padding-left: 15px;
    }
  }
  
  @media (min-width: 576px) {
    .container {
      width: 540px;
      max-width: 100%;
    }
  }
  
  @media (min-width: 768px) {
    .container {
      width: 720px;
      max-width: 100%;
    }
  }
  
  @media (min-width: 992px) {
    .container {
      width: 960px;
      max-width: 100%;
    }
  }
  
  @media (min-width: 1200px) {
    .container {
      width: 1140px;
      max-width: 100%;
    }
  }