:root{
    background-color: #ecf5ff;
    font-size: 62.5%;
}

body {
    background-image: url('');
    background-size: cover;
    background-repeat: no-repeat;
}

*{
    box-sizing: border-box; 
    font-family: Arial, Helvetica, sans-serif;
    margin: 0;
    padding: 0;
    color: #333;
}

h1,
h2,
h3,
h4 {
    margin-bottom: 1rem;
    /* same as 62.5% of 16px = 10px */
} 

h1 {
    font-size: 5.4rem; /* same as 5.4 x 10px = 54px*/
    color: #56a5eb;
    margin-bottom: 5rem;
}

h1 > span{
    font-size: 2.5rem;
    font-weight: 500;
}

h2 {
    font-size: 4.2rem;
    margin-bottom: 4rem;
    font-weight: 700;
}

h3 {
    font-size: 2.8rem;
    font-weight: 500;
}

.container{
    width: 100vw;
    height: 100vh;

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

    max-width: 80rem;
    margin: 0 auto;
    /*to keep all stuff centered while we minimize  */
    padding: 2rem;
}

.container > * {
    width: 100%;
}

.flex-column {
    display: flex;
    flex-direction: column;
}

.flex-center{
    justify-content: center;
    align-items: center;
}

.justify-center {
    justify-content: center;
}

.text-center {
    text-align: center;
}

.hidden {
    display: none;
}

/* buttons */
.btn {
    font-size: 1.8rem;
    padding: 1rem 0;
    width: 20rem ;
    text-align: center;
    border: 0.1rem solid #56a5eb;
    margin-bottom: 1rem;
    color: #56a5eb;
    background-color: white;
    text-decoration: none;
}

.btn:hover {
    cursor: pointer;
    box-shadow: 0 0.4rem 0 rgba(86, 185, 235, 0.5);
    
    transform: translateY(-0.1rem);
    transition: transform 150ms;
}

.btn[disabled]:hover{
    cursor: not-allowed;
    box-shadow: none;
    transform: none;
}

form {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
}

input {
    margin-bottom: 3rem;
    font-size: 1.8rem;
    border: none;
    box-shadow: 0.0.1rem 1.4rem 0 rgb(160, 212, 252);
    padding: 1.5rem;
    width: 20rem;
}

input::placeholder {
    color: #aaa;
}