.top-container {
    margin: 2em auto;
    max-width: 1000px;
    display: flex;
    flex-direction: row;
    justify-content: center;
}

.menu {
    margin: 0 auto;
    background-color: #4CAF50;
    /*max-width: 20%;*/
    flex: 1;
}


.container {
    width: 80%;
    flex: 4;
}

.content {
    margin: 0 auto;
    background-color: aliceblue;
}

.menu ul {
    padding: 0;
}

.menu li {
    list-style-type: none;
    margin: 1em auto;
    border: 1px solid #666666;
    text-align: center;
    font-size: 18px;
}

.menu li:hover {
    background-color:aliceblue;
}

.active {
    background-color: aliceblue;
}

.hidden {
    display: none;
}

.show {
    display: inline-block;
}

tr:hover{
    opacity: 0.5;
    cursor: pointer;
    margin: 1px auto;
}

#mail-form{
    width: 100%;
    margin: 1em 1em;
}

#mail-container input {
    width: 100%;
}

textarea {
    width: 100%;
    height: 5em;
}

.relative-container {
    position: relative;
}

.username-selector {
    position: absolute;
    display: none;
    z-index: 9;
    background-color: #fff;
    border: 1px solid;
    box-shadow: 3px 3px 1px grey;
    min-width: 5em;
    min-height: 3em;
}

.username-selector div:hover {
    background-color: aliceblue;
    opacity: 0.8;
    cursor: pointer;
    font-weight: bold;
}

.errmsg {
    color: red;
}



/* audio record */
#audio-container canvas {
    width: 10em;
    height: 3em;
}

#audio-container img {
    height: 3em;
}

#audio-container .audio-box {
    display: flex;
    margin: 1em auto;
}

#audio-container .tile{
    height: 3em;
    margin: auto 1em;
}