@import url(https://fonts.googleapis.com/css?family=Open+Sans);
*,
*::before,
*::after {
    box-sizing: border-box;
}

body {
    margin: 30px;
    background-color: #f0f0f0;
}

#marksBox,
#content {
    width: 460px;
    height: 180px;
}

#marks,
textarea {
    padding: 10px;
    font: 20px/28px 'Open Sans', sans-serif;
    letter-spacing: 1px;
}

#marksBox {
    position: absolute;
    z-index: 1;
    border: 2px solid #685972;
    background-color: #fff;
    overflow: auto;
    pointer-events: none;
    transition: transform 1s;
}

#marks {
    white-space: pre-wrap;
    word-wrap: break-word;
    color: transparent;
}

#contentBox {
    display: block;
    margin: 0 auto;
    transform: translateZ(0);
    width: 460px;
    height: 180px;
}

#content {
    display: block;
    position: absolute;
    z-index: 2;
    margin: 0;
    border: 2px solid #74637f;
    border-radius: 0;
    color: #444;
    background-color: transparent;
    overflow: auto;
    resize: none;
    transition: transform 1s;
}

mark {
    border-radius: 3px;
    color: transparent;
    background-color: #b1d5e5;
}

#luckyBtn {
    display: block;
    width: 300px;
    margin: 30px auto 0;
    padding: 10px;
    border: none;
    border-radius: 6px;
    color: #fff;
    background-color: #74637f;
    font: 18px 'Opens Sans', sans-serif;
    letter-spacing: 1px;
    appearance: none;
    cursor: pointer;
}

textarea:focus {
    outline: none;
    box-shadow: 0 0 0 2px #c6aada;
}

#regexBox {
    display: block;
    margin: 0 auto;
    width: 460px;
    height: 60px;
}

#regex {
    border: 2px solid #74637f;
    width: 435px;
    color: #333333;
    padding: 3px;
    font-family: courier, sans-serif;
    font-size: 24px;
}

.centered {
    display: block;
    margin: 0 auto;
    width: 460px;
}


.chars {
    margin-bottom: 10px;
}

span {
    color: #74637f;
}

.charBtn {
    border: none;
    border-radius: 3px;
    color: #fff;
    background-color: #74637f;
    font-weight: bold;
    cursor: pointer;
    outline: none;
}

.charBtn:hover{
    background-color: #9c89a8;
}

#epsilonBtn{
    padding: 0 8px 0 8px;
    font-size: 16px;
}

#unoImg {
    position: absolute;
    margin-left: 3px;
    height: 35px;
}

#unoImg:hover{
    box-shadow: 0 0 0 2px #c6aada;
    cursor: hand;
}

#unoImg:active{
    opacity: 70%;
}