style.css

html, body, #map {
    height: 100%;
    margin: 0;
    padding: 0;
    position: relative;
}

iframe {
    height: 100%;
    width: 100%;
    border: 0;
    margin: 0;
    padding: 0;
}

button {
    font-family: 'Open Sans', sans-serif; 
}

.showLegend {
    display: none;
    cursor: pointer;
}

.hideLegend {
    position: absolute;
    bottom: 20px;
    right: 5px;
    z-index: 1;
    cursor: pointer;
}

.legend {    
    background: white;
    border-radius: 4px;
    box-shadow: 0 2px 4px 0 rgba(0, 0, 0, 0.24);
    box-sizing: border-box;
    display: none;
    font-family: 'Open Sans', sans-serif; 
    font-size: 12px;
    font-weight: 600;
    padding: 20px;
    height: 200px;
    white-space: nowrap;
    overflow-y: hidden;
    overflow-x: auto;
}

.legendSVG {
    height: 150px;
}

.chevron-right-fade {
    position: absolute;
    top: 0;
    right: 0;
    width: 50px;
    height: 100%;
    background: -webkit-linear-gradient(
        to right,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    ); 
    background-image: -moz-linear-gradient(
        to right,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    );
    background-image: -o-linear-gradient(
        to right,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    );
    background-image: linear-gradient(
        to right,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    );
    background-image: -ms-linear-gradient(
        to right,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    );
}

.chevron-right-fade:hover {
    background: transparent;
    cursor: pointer;
}

.chevron-right-wrapper {
    position: absolute;
    top: 37%;
    right: 0;
    color: #777;
}

.chevron-right-wrapper.hover {
    color: #333;
    cursor: pointer;
}


.chevron-left-fade {
    display: none;
    position: absolute;
    top: 0;
    left: 0;
    width: 50px;
    height: 100%;
    background: -webkit-linear-gradient(
        to left,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    ); 
    background-image: -moz-linear-gradient(
        to left,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    );
    background-image: -o-linear-gradient(
        to left,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    );
    background-image: linear-gradient(
        to left,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    );
    background-image: -ms-linear-gradient(
        to left,
        rgba(255, 255, 255, 0) 0%,
        rgba(255, 255, 255, 1) 100%
    );
}

.chevron-left-fade:hover {
    background: transparent;
    cursor: pointer;
}

.chevron-left-wrapper {
    position: absolute;
    top: 37%;
    left: 0;
    color: #777;
}

.chevron-left-wrapper.hover {
    color: #333;
    cursor: pointer;
}


.legend-wrapper {
    position: absolute;
    top: 20px;
    left: 20px;
    max-width: calc(100vw - 54px);
} 

@media (min-width: 616px) { 
    .legend-wrapper {
        left: 276px;
        max-width: calc(100vw - 100px);
    } 
}

@media (min-width: 775px) { 
    .legend-wrapper {
        top: 24px;
        max-width: calc(100vw - 600px);
    } 
}

@media (min-width: 1215px) {
    .legend-wrapper {
        top: 32px;
        left: 344px;
        max-width: calc(100vw - 675px);
    } 
}

@media (min-width: 1315px) {
    .legend-wrapper {
        max-width: calc(100vw - 750px);
    } 
}