body{
    font-family:Arial,Helvetica,sans-serif;
    background:#f4f6f8;
    margin:0;
    padding:40px;
}

.container{
    max-width:1000px;
    margin:auto;
}

h1{
    text-align:center;
    margin-bottom:30px;
    color:#111827;
}

details{
    background:#fff;
    border-radius:12px;
    margin-bottom:12px;
    overflow:hidden;
    box-shadow:0 2px 8px rgba(0,0,0,.08);
}

summary{
    padding:18px 20px;
    cursor:pointer;
    font-weight:bold;
    color:#111827;
    list-style:none;
    font-size:16px;
}

summary::-webkit-details-marker{
    display:none;
}

summary:after{
    content:"+";
    float:right;
    font-size:20px;
}

details[open] summary:after{
    content:"−";
}

.respuesta{
    padding:0 20px 20px 20px;
    line-height:1.7;
    color:#374151;
}