#st-wrap{
    text-align:center;
    padding:20px;
    background:#f8f8f8;
    border-radius:14px;
    max-width:700px;
    margin:auto;
    box-shadow:0 2px 8px rgba(0,0,0,0.08);
}
``

#st-info{
    display:flex;
    justify-content:center;
    align-items:center;
    margin:15px 0 8px;
    font-size:18px;
    font-weight:bold;
}

#st-settime{
    color:#3CB371;
    padding-right:12px;
    margin-right:12px;
    border-right:2px solid #ccc;
}

#st-label{
    color:#444;
}

.st-btn{
    background:#87CEFA;
    color:#fff;
    border:none;
    border-radius:8px;
    padding:12px 20px;
    margin:4px;
    font-size:18px;
    font-weight:bold;
    cursor:pointer;
}

.st-btn:hover{
    background:#6CB8E6;
}

.clear-btn{
    background:#3CB371;
}

.start-btn,
.stop-btn,
.reset-btn{
    color:#fff;
    border:none;
    border-radius:20px;
    padding:12px 24px;
    font-size:18px;
    margin:4px;
    cursor:pointer;
}

.start-btn{
    background:#FFB6A3;
}

.stop-btn{
    background:#87CEFA;
}

.reset-btn{
    background:#3CB371;
}

#st-circle-wrap{
    position:relative;
    width:220px;
    height:220px;
    margin:20px auto;
}

#st-display{
    position:absolute;
    top:50%;
    left:50%;
    transform:translate(-50%,-50%);
    font-size:42px;
    font-weight:bold;
}

#st-history{
    max-height:220px;
    overflow:auto;
    border:1px solid #ccc;
    border-radius:10px;
    padding:8px;
    background:#f2f2f2;
}

#st-finish{
    display:none;
    font-weight:bold;
    font-size:28px;
    color:#d63384;
}