styles.css

html,
body {
    width: 100%;
    height: 100%;
    margin: 0;
    font-family: 'Noto Sans TC', sans-serif;
    font-size: 16px;
    line-height: 22px;
    font-weight: 300;
    position: relative;
}

.sidebar {
    width: 280px;
    height: 100%;
    padding: 40px;
    box-sizing: border-box;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 2;
    background: #FFFFFF;
    border-radius: 0 10px 10px 0;
    box-shadow: 4px 0 8px 0 rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease-in-out;
    overflow: hidden;
    /* animation-name: sidebarMove;
    animation-duration: 1s; */
}

.top {
    justify-content: flex-start;
}

.center {
    justify-content: center;
}

.bottom {
    justify-content: flex-end;
}

.more {
    height: 64px;
    width: 40px;
    color: rgb(101, 104, 121);
    border-radius: 100%;
    line-height: 36px;
    font-size: 40px;
    justify-content: flex-end;
    box-sizing: border-box;
    display: none;
    transition: all 0.3s ease-in-out;
}

.more::before {
    border-style: solid;
    border-width: 4px 4px 0 0;
    content: '';
    display: inline-block;
    transform: rotate(-45deg);
    height: 12px;
    left: 30%;
    position: relative;
    top: 28px;
    vertical-align: top;
    width: 12px;
}

.more:hover, .add:hover{
    cursor: pointer;
}

.logo {
    background: url(assets/logo-day.svg);
    background-position: center center;
    background-repeat: no-repeat;
    height: 90px;
    justify-content: center;
}

.howto {
    margin: 0 0 40px 0;
    color: #646978;
}

.legend {
    margin: 0;
    padding: 0;
    margin-bottom: 88px;
}

.legend li {
    list-style: none;
    color: #646978;
    padding-left: 24px;
}

.legend li h3 {
    font-size: 16px;
    font-weight: 400;
    color: #646978;
    margin: 20px 0 0 0;
    /* text-transform: uppercase;
    letter-spacing: 2px; */
    position: relative;
}

.legend h3::before {
    content: "•";
    font-size: 80px;
    position: absolute;
    left: -58px;
    top: -1px;
  }

.legend .item1 h3::before {
    color: #3a7bbf;
}

.legend .item2 h3::before {
    color: #99e0dc;
}

.legend .item3 h3::before {
    color: #ae65d5;
}

.legend li p {
    font-size: 14px;
    font-weight: 300;
    margin: 0;
}

#toggleTime {
    opacity: 0;
}

.creditsleft {
    float: left;
}

.creditsright {
    float: right;
    margin-top: -4px;
    background-image: url(assets/toggle-day.svg);
    background-position: center center;
    background-repeat: no-repeat;
    height: 24px;
    width: 48px;
    justify-content: center;
}

.creditsleft, .creditsleft a {
    font-size: 14px;
    line-height: 16px;
    text-transform: none;
    color: #646978;
    margin-bottom: -16px;
    text-decoration: none;
    transition: all 0.3s ease-in-out;
}

.credits a:hover {
    color: #ec4667;
}

#photo, #photobg {
    background-color: #e5e8ef;
    position: absolute;
    z-index: 4;
    top: 20px;
    right: 20px;
    height: 200px;
    width: 300px;
    border-radius: 10px;
    opacity: 1;
    pointer-events: none;
}

#photo {
    background-repeat: no-repeat;
    background-size: cover;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.45);
    overflow: hidden;
    z-index: 5;
}

#photo.hidden, #photobg.hidden {
    opacity: 0;
    transition: all 0.3s;
}

#label {
    color: white;
    background: rgba(0, 0, 0, 0.6);
    margin: 0;
    padding: 12px 16px 24px;
    font-weight: 400;
    text-shadow: 0 2px 4px #00000060;

    /* Permalink - use to edit and share this gradient: http://colorzilla.com/gradient-editor/#000000+0,000000+100&0.6+0,0+100 */
    background: -moz-linear-gradient(top, hsla(0, 0%, 0%, 0.8) 0%, hsla(0, 0%, 0%, 0) 100%);
    /* FF3.6-15 */
    background: -webkit-linear-gradient(top, hsla(0, 0%, 0%, 0.8) 0%, hsla(0, 0%, 0%, 0) 100%);
    /* Chrome10-25,Safari5.1-6 */
    background: linear-gradient(to bottom, hsla(0, 0%, 0%, 0.8) 0%, hsla(0, 0%, 0%, 0) 100%);
    /* W3C, IE10+, FF16+, Chrome26+, Opera12+, Safari7+ */
    filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#99000000', endColorstr='#00000000', GradientType=0);
    /* IE6-9 */
}

#mapid {
    width: 100%;
    height: 100%;
    z-index: 1;
}

.leaflet-top {
    right: 0;
}

.addsound {
    width: 64px;
    height: 64px;
    text-align: center;
    background-color:#ec4667;
    color: white;
    text-decoration: none;
    border-radius: 100%;
    position: absolute;
    bottom: 20px;
    right: 20px;
    z-index: 6;
    line-height: 62px;
    font-size: 40px;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease-in-out;
}

.addsound:hover {
    background-color: #ec4667;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.4);
}



/* @keyframes sidebarMove {
    0%   {left:-280px;}
    100% {left:0px;}
  } */

@media only screen and (max-width: 600px) {
    .sidebar {
        width: 100%;
        height: 416px;
        /* 416 */
        padding: 20px;
        /* flex-direction: row; */
        border-radius: 0 0 10px 10px;
        box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2);
        /* animation-name: sidebarMove;
        animation-duration: 1s; */
    }

    .top {
        position: relative;
    }

    .logo {
        height: 64px;
        width: 120px;
        background-position: left center;
        float: left;
    }

    .more {
        display: block;
        float: right;
    }

    .howto{
        margin: 24px 0;
        max-width: 430px;
    }

    .legend {
        margin-bottom: 32px;
    }

    .credits {
        margin: 0;
    }

    .center, .bottom {
        /* display: none; */
        /* visibility: hidden; */
        opacity: 1;
        transition: all 0.3s ease-in-out;
    }

    #photo, #photobg {
        top: auto;
        right: auto;
        bottom: 0;
        left: 0;
        height: 240px;
        width: 100%;
        border-radius: 8px 8px 0 0;
    }
    
}