:root {
    background: #ecf5ff;
    font-size: 62.5%; /* Default font-size is 16px, so this equals to 10px - anything we reference with rems will be based on 10px */
}

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

h1, 
h2,
h3,
h4 {
    margin-bottom: 0;
}

h1 {
    font-size: 5.4rem;
    color: #56a5eb;
    margin-bottom: 5rem;
}

h1 > span {
    font-size: 2.4rem;
    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; /* Horizontal */
    align-items: center; /* Vertical */
    max-width: 80rem;
    margin: 0 auto;
    padding: 2rem;
}

/* Children of container */
.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;
    text-decoration: none;
    color: #56a5eb;
    background-color: white;
}

.btn:hover {
    cursor: pointer;
    box-shadow: 0 0.4rem 1.4rem 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 */
form {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
}

input {
    margin-bottom: 1rem;
    width: 20rem;
    padding: 1.5rem;
    font-size: 1.8rem;
    border: none;
    box-shadow: 0 0.1rem 1.4rem 0 rgba(86, 185, 235, 0.5);
}

input::placeholder {
    color: #aaa;
}