body {
    font-family: "Roboto", sans-serif;
    background-color: #eff2f7;;
}

.main {
    position: absolute;
    width: 300px;
    top: 47%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
}

.main > input {
    position: relative;
    display: inline-block;
    width: 100%;
    height: 35px;
    border: none;
    padding-left: 15px;
    border-radius: 5px;
    font-size: 80%;
}

.main > button {
    position: relative;
    width: calc(100% + 15px);
    height: 37px;
    border: none;
    border-radius: 5px;
    font-size: 80%;
    background-color: #00e636;
    cursor: pointer;
}

.main > span.title {
    font-size: 150%;
    padding-bottom: 20px;
}

#error {
    position: relative;
    display: inline-block;
    color: red;
}