.flex-box {
           display: flex; 
          flex-wrap: wrap;; 
          justify-content:center; 
          align-items:  flex-start;
          align-content: center;
          clear:left;
      }
      
  .subscribe-form {
     display: flex; 
     flex-wrap: nowrap; 
     justify-content:center; 
     align-items:  flex-start;
     align-content: center;
     clear:left;
  }
  .email-field {
   flex:1 1;
  } 
  .subscribe-button{
  flex:0 0 auto;      
  }