style.css

html {
    height: 100%;
}

body {
    height: 100%;
    position: relative;
    background: #000 url(static/bg.min.jpg) no-repeat scroll 0 0;
    background-size: cover;
    font-family: 'Open Sans', Helvetica, Arial, sans-serif;
    color: #fff;
    overflow: hidden;
}

a,
a:hover {
    text-decoration: none;
}

input::-webkit-input-placeholder {
    color: #fff;
    font-size: 75%;
    line-height: 1.5em;
    font-weight: 300;
    transition: all 0.5s;
}

input::-moz-placeholder {
    color: #fff;
    font-size: 75%;
    line-height: 1.5em;
    font-weight: 300;
    transition: all 0.5s;
}

input::-ms-input-placeholder {
    color: #fff;
    font-size: 75%;
    line-height: 1.5em;
    font-weight: 300;
    transition: all 0.5s;
}

input:focus::-webkit-input-placeholder {
    color: transparent;
}

input:focus::-moz-placeholder {
    color: transparent;
}

input:focus::-ms-input-placeholder {
    color: transparent;
}

.container {
    display: flex;
    height: 90%;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    transition: height 0.5s;
}

.container-header {
    font-weight: 300;
    margin: 0;
    padding: 0;
    opacity: 1;
    transition: all 0.5s;
}

.container-header.done {
    margin: 0 0 1em 0;
}

.container-header.input-focus {
    opacity: 0.5;
}

.container-form {
    display: block;
    width: 80%;
    position: relative;
}

.container-form.hide {
    display: none;
}

.container-form-input {
    display: block;
    color: #122E62;
    background: rgba(255, 255, 255, 0.60);
    border: 0;
    border-radius: 1.5rem;
    height: 3rem;
    width: calc(100% - 4rem);
    font-size: 2em;
    line-height: 2.5rem;
    text-align: center;
    margin: 0;
    padding: 0 3.5rem 0 0.5rem;
    transition: all 0.25s;
}

.container-form-input:focus {
    box-shadow: -5px 0 20px #fff, 0 -5px 20px #fff, 5px 0 20px #fff, 5px 0 20px #fff, -5px 5px 20px #fff, 5px 5px 20px #fff;
    outline: none;
}

.container-form-button {
    display: block;
    position: absolute;
    top: 0;
    right: 0;
    padding: 0;
    margin: 0;
    border: none;
    background: rgba(255, 255, 255, 0.25);
    border-radius: 50%;
    width: 3rem;
    height: 3rem;
}

.container-form-button:focus {
    outline: none;
}

.container-form-button-icon {
    display: block;
    width: 32px;
    height: 32px;
    margin: 0 auto;
    text-align: center;
}

.container-form-button-icon > * {
    fill: #fff;
}

.container-form-button:hover .container-form-button-icon > *,
.container-form-button.focused .container-form-button-icon > * {
    fill: #122E62;
}

.container-counter {
    width: 100%;
    text-align: center;
    margin: 2em 0 0 0;
    flex: none;
    text-shadow: 0 1px 3px black;
    transition: color 0.5s, transform 1s, text-shadow 0.5s;
}

.container-counter.hide {
    position: relative;
    transform: translate(0, 50px);
    color: transparent;
    text-shadow: 0 1px 3px transparent;
}

.container-counter p {
    margin: 0;
}

.container-done-msg {
    width: 100%;
    text-align: center;
    flex: none;
    text-shadow: 0 1px 3px black;
    transition: color 0.5s, transform 1s, text-shadow 0.5s;
}

.container-done-msg.hide {
    position: relative;
    transform: translate(0, 50px);
    color: transparent;
    text-shadow: 0 1px 3px transparent;
}

.container-done-msg p {
    margin: 0;
}

.accordion-section {
    width: 80%;
    text-align: center;
    position: absolute;
    bottom: 0;
    left: 10%;
}

.accordion-section-title {
    display: inline-block;
    color: #fff;
    border-bottom: 1px dashed #fff;
}

.accordion-section-content {
    height: auto;
    max-height: 0;
    overflow: hidden;
    margin: 1em 0;
    opacity: 0;
    visibility: hidden;
    transition: opacity 1s, visibility 1s, max-height 1s;
}

.accordion-section-content.active {
    max-height: 325px;
    opacity: 1;
    visibility: visible;
}

.accordion-section-content svg {
    vertical-align: bottom;
}

.accordion-section-content svg > * {
    fill: #fff;
}

.accordion-section-content span {
    display: block;
}

@media screen and (max-width: 600px) {

    .container {
        height: 45%;
    }

}

.link {
    display: inline-block;
    color: #fff;
    border-bottom: 1px dashed #fff;
}

.link.hide {
    position: relative;
    transform: translate(0, 50px);
    color: transparent;
    text-shadow: 0 1px 3px transparent;
    border-bottom: none;
}