.main{
    margin: 5% 10% auto 10%;
    text-align: center;
}

.testimonial-container {
    margin: auto 10%;
    display: flex;
    justify-content: space-around;
    padding: 20px;
}

.testimonial {
    background-color: #DFF3FF;
    border: 1px solid #ddd;
    padding: 20px;
    margin: 10px;
    width: 30%; 
    text-align: center;
}

div.main-idea{
    min-height: calc(100vh - 54px);
    height: fit-content;
    width: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.heading h1{
    display: inline;
}

.second-color-heading{
    color: #246365;
}

.main-idea .heading{
    margin-bottom: 50px;
}

.main-idea p, .textbox p{
    width: 67%;
    text-align: justify;
}

#why-pen{
    margin: 100px auto 50px auto;
}

div.textbox{
    height: 20%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.product-img{
    max-width: 100%;
}

/* specifying behaviour when on phone size screen */
@media screen and (max-width: 600px){
    .main{
        margin: 5% 5% auto 5%;
        text-align: center;
    }

    .testimonial-container {
        margin: auto 5%;
        flex-direction: column;
    }
    
    .testimonial {
        width: 90%;
    }

    .main-idea p, .textbox p{
        width: 90%;
    }
}