body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: #f0f2f5;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    transition: background-color 0.3s ease;
    /* Защита от выделения текста на всей странице */
    -webkit-user-select: none; 
    -moz-user-select: none;    
    -ms-user-select: none;     
    user-select: none;         
}
.card {
    background: #ffffff;
    padding: 40px 30px;
    border-radius: 20px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
    text-align: center;
    max-width: 400px;
    width: 90%;
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}
.logo {
    font-size: 50px;
    margin-bottom: 20px;
}
h1 {
    color: #222;
    font-size: 22px;
    margin: 0 0 10px 0;
    transition: color 0.3s ease;
}
p {
    color: #666;
    font-size: 15px;
    line-height: 1.5;
    margin-bottom: 25px;
    transition: color 0.3s ease;
}
.copy-box {
    background: #f4f8fb;
    border: 2px dashed #cbd5e1;
    border-radius: 12px;
    padding: 15px;
    margin-bottom: 20px;
    cursor: pointer;
    transition: all 0.2s ease;
    -webkit-user-select: auto; 
    -moz-user-select: auto;    
    -ms-user-select: auto;     
    user-select: auto;         
}
.copy-box:hover {
    border-color: #0088cc;
    background: #e8f4fd;
}
.copy-box span {
    font-size: 20px;
    font-weight: 600;
    color: #0088cc;
    font-family: monospace;
    transition: color 0.2s ease;
}
.hint {
    font-size: 13px;
    color: #888;
    transition: color 0.3s ease;
}
.success-msg {
    color: #22c55e;
    font-weight: 600;
    font-size: 14px;
    margin-top: 10px;
    opacity: 0;
    transition: opacity 0.3s;
}
.success-msg.show {
    opacity: 1;
}

@media (prefers-color-scheme: dark) {
    body {
        background-color: #121212;
    }
    .card {
        background: #1e1e1e;
        box-shadow: 0 10px 25px rgba(0,0,0,0.4);
    }
    h1 {
        color: #e0e0e0;
    }
    p {
        color: #a0a0a0;
    }
    .copy-box {
        background: #2a2a2a;
        border-color: #444444;
    }
    .copy-box:hover {
        border-color: #4db8e8;
        background: #253545;
    }
    .copy-box span {
        color: #4db8e8;
    }
    .hint {
        color: #666666;
    }
}