.container1 {
        margin-top: 2rem;
        margin-bottom: 2rem;
        max-width: 920px;
        margin-inline: auto;
        padding: clamp(1rem, 3vw, 1.5rem);
        border-radius: 20px;
        border: 1px solid transparent;
        transition: background .2s ease, color .2s ease, border-color .2s ease, box-shadow .2s ease;
    }
    .logo { height: 50px; }


    /* Light mode */
    body.theme-light .container1 {
        background: #ffffff;
        color: #0f172a;
        border-color: rgba(203, 213, 225, 0.6);
        box-shadow: 0 24px 48px rgba(15, 23, 42, 0.06);
    }

    /* Dark mode */
    body.theme-dark .container1 {
        background: rgba(15, 23, 42, 0.9);
        color: #e2e8f0;
        border-color: rgba(148, 163, 184, 0.18);
        box-shadow: 0 24px 48px rgba(2, 6, 23, 0.4);
    }

    .container1 h2 {
        margin: 0 0 0.75rem;
        font-weight: 800;
        letter-spacing: 0.2px;
        text-align: center;
    }

    .container1 a { text-decoration: underline; }
    body.theme-light .container1 a { color: #1d4ed8; }
    body.theme-dark .container1 a { color: #93c5fd; }