*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

        :root {
            --primary: #004673;
            --primary-light: #0088b8;
            --accent: #bee4fb;
            --accent-mid: #a7d3ed;
            --gray-mid: #718fa6;
            --gray-darker: #506b80;  /* WCAG-AA-konform auf weiß (5.36:1) — für Body-Text wie Footer */
            --bg: #f0f7fb;
            --white: #ffffff;
            --dark: #00213a;
            --dark-2: #002E52;
            --highlight: #0088b8;
            --green: #AAD084;
            --cyan: #33b2ca;
            --sidebar-w: 320px;
            --header-h: 80px;
            --radius: 1rem;
            --radius-lg: 2rem;
            --shadow: 0 3px 20px rgba(167,211,237,0.35);
            --shadow-sm: 0 2px 10px rgba(167,211,237,0.2);
            --transition: 0.3s ease;
        }

        html { font-size: 62.5%; scroll-behavior: smooth; }

        body {
            font-family: 'Inter', sans-serif;
            font-weight: 300;
            font-size: 1.5rem;
            line-height: 2.6rem;
            color: var(--primary);
            background: var(--white);
            overflow-x: hidden;
        }

        a { color: inherit; text-decoration: none; }

        /* ===== SKIP LINK (Accessibility) =====
           Tastatur-Nutzer:innen können mit Tab vor allen Navigations-Links
           direkt zum Hauptinhalt springen. Sichtbar nur bei Fokus. */
        .skip-link {
            position: absolute;
            top: 0;
            left: 0;
            padding: 1rem 1.6rem;
            background: var(--primary);
            color: var(--white);
            font-size: 1.5rem;
            font-weight: 600;
            border-radius: 0 0 var(--radius) 0;
            z-index: 2000;
            transform: translateY(-110%);
            transition: transform 0.2s ease;
        }
        .skip-link:focus { transform: translateY(0); outline: 3px solid var(--accent); outline-offset: 2px; }

        /* Konsistenter Fokus-Ring für Tastatur-Navigation */
        :focus-visible {
            outline: 3px solid var(--primary-light);
            outline-offset: 2px;
            border-radius: 4px;
        }

        /* ===== HEADER ===== */
        .header {
            position: fixed;
            top: 0; left: 0; right: 0;
            height: var(--header-h);
            background: var(--white);
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 0 2rem;
            z-index: 1000;
            border-bottom: 1px solid rgba(0,70,115,0.06);
        }

        .header-left { display: flex; align-items: center; gap: 2rem; }

        .logo { display: flex; align-items: center; cursor: pointer; }
        .logo svg, .logo img { height: 4.5rem !important; width: auto !important; }

        .header-tag {
            font-size: 1.3rem;
            font-weight: 600;
            color: var(--primary);
            background: var(--accent);
            padding: 0.5rem 1.4rem;
            border-radius: 2.5rem;
        }

        .header-right { display: flex; align-items: center; gap: 1.6rem; }

        /* ===== MOBILE MENU TOGGLE ===== */
        .menu-toggle {
            display: none;
            width: 4rem;
            height: 4rem;
            background: transparent;
            border: none;
            padding: 0.8rem;
            cursor: pointer;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            color: var(--primary);
        }
        .menu-toggle span {
            display: block;
            width: 2.4rem;
            height: 2px;
            background: currentColor;
            border-radius: 2px;
            transition: transform 0.25s ease, opacity 0.25s ease;
        }
        body.menu-open .menu-toggle span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
        body.menu-open .menu-toggle span:nth-child(2) { opacity: 0; }
        body.menu-open .menu-toggle span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

        .sidebar-backdrop {
            display: none;
            position: fixed;
            top: var(--header-h);
            left: 0; right: 0; bottom: 0;
            background: rgba(0, 33, 58, 0.45);
            z-index: 880;
            opacity: 0;
            transition: opacity 0.25s ease;
        }
        body.menu-open .sidebar-backdrop {
            display: block;
            opacity: 1;
        }


        /* CTA Button — matches 506.ai style */
        .cta-btn {
            display: inline-flex;
            align-items: center;
            gap: 0.6rem;
            background: var(--accent);
            color: var(--primary);
            font-family: 'Inter', sans-serif;
            font-size: 1.6rem;
            font-weight: 600;
            padding: 1.1rem 2.2rem;
            border-radius: 2.5rem;
            border: none;
            cursor: pointer;
            transition: var(--transition);
        }
        .cta-btn:hover { background: var(--primary); color: var(--white); }

        .cta-btn-dark {
            background: var(--primary);
            color: var(--white);
        }
        .cta-btn-dark:hover { background: var(--dark); }

        /* ===== SIDEBAR ===== */
        .sidebar {
            position: fixed;
            top: var(--header-h);
            left: 0;
            width: var(--sidebar-w);
            height: calc(100vh - var(--header-h));
            background: var(--white);
            border-right: 1px solid rgba(0,70,115,0.06);
            overflow-y: auto;
            z-index: 900;
            padding: 2.4rem 0;
        }

        .sidebar::-webkit-scrollbar { width: 3px; }
        .sidebar::-webkit-scrollbar-thumb { background: var(--accent); border-radius: 3px; }

        .nav-news {
            display: flex;
            align-items: center;
            gap: 0.8rem;
            padding: 0.8rem 2.4rem;
            font-size: 1.6rem;
            font-weight: 600;
            color: var(--primary);
            cursor: pointer;
            transition: var(--transition);
            margin-bottom: 0;
        }
        .nav-news:hover { background: var(--bg); }
        .nav-news .badge {
            margin-left: auto;
            background: var(--highlight);
            color: var(--white);
            font-size: 1rem;
            font-weight: 700;
            padding: 0.2rem 0.8rem;
            border-radius: 2rem;
        }

        .nav-divider { height: 1px; background: rgba(0,70,115,0.06); margin: 1.2rem 2.4rem; }

        /* "NEU"-Badge — kann in Sidebar, News-Cards oder anderen Stellen verwendet werden */
        .badge-new {
            display: inline-block;
            background: var(--highlight);
            color: var(--white);
            font-size: 1rem;
            font-weight: 700;
            padding: 0.15rem 0.7rem;
            border-radius: 2rem;
            margin-left: 0.8rem;
            vertical-align: middle;
            letter-spacing: 0.05em;
            text-transform: uppercase;
        }
        /* In Headlines (h3 in News-Cards) etwas größer, damit's nicht zu klein wirkt */
        h3 .badge-new { font-size: 1.1rem; padding: 0.2rem 0.9rem; }

        /* nav-section-title ist ein <button> — Default-Button-Styles zurücksetzen,
           damit es optisch identisch zum vorherigen <div> aussieht. */
        .nav-section-title {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 0.8rem;
            width: 100%;
            padding: 0.8rem 2.4rem;
            font-family: inherit;
            font-size: 1.6rem;
            font-weight: 600;
            color: var(--primary);
            background: transparent;
            border: none;
            text-align: left;
            letter-spacing: 0;
            margin-top: 0.8rem;
            cursor: pointer;
            user-select: none;
            transition: var(--transition);
        }
        .nav-section-title:hover { background: var(--bg); }
        .nav-chevron {
            font-size: 1.1rem;
            opacity: 0.55;
            transition: transform 0.2s ease;
            flex: 0 0 auto;
        }
        .nav-section.collapsed .nav-chevron { transform: rotate(-90deg); }
        .nav-section.collapsed .nav-item { display: none; }

        .nav-item {
            display: block;
            padding: 0.8rem 2.4rem 0.8rem 5rem;
            font-size: 1.6rem;
            font-weight: 400;
            color: var(--primary);
            opacity: 0.8;
            cursor: pointer;
            transition: var(--transition);
            position: relative;
        }
        .nav-item:hover { opacity: 1; background: var(--bg); }
        .nav-item.active,
        .nav-item[aria-current="page"] {
            opacity: 1;
            font-weight: 600;
            background: linear-gradient(90deg, var(--bg), transparent);
        }
        .nav-item.active::before,
        .nav-item[aria-current="page"]::before {
            content: '';
            position: absolute;
            left: 0; top: 0; bottom: 0;
            width: 3px;
            background: var(--primary);
            border-radius: 0 3px 3px 0;
        }

        /* ===== MAIN ===== */
        .main {
            margin-left: var(--sidebar-w);
            margin-top: var(--header-h);
            min-height: calc(100vh - var(--header-h));
        }

        .main-inner { padding: 5rem 6rem; }

        /* ===== HERO — matches 506.ai gradient style ===== */
        .hero {
            background: linear-gradient(90deg, #f0f7fb, #bee4fb);
            border-radius: 0 0 3rem 3rem;
            padding: 6rem 3rem 6.5rem;
            margin-bottom: 0;
            position: relative;
            overflow: hidden;
        }

        .hero-inner { padding: 0 3rem; }

        .hero h1 {
            font-size: 3.8rem;
            font-weight: 700;
            line-height: 4.6rem;
            color: var(--primary);
            margin-bottom: 1.2rem;
        }

        .hero p {
            font-size: 1.8rem;
            font-weight: 300;
            color: #004673;
            opacity: 1;
            max-width: 56rem;
            line-height: 3rem;
        }

        /* ===== SECTIONS ===== */
        .section { margin-bottom: 5rem; }

        .section-header {
            display: flex;
            align-items: center;
            gap: 1.4rem;
            margin-bottom: 2.4rem;
        }

        .section-icon {
            width: 4.4rem;
            height: 4.4rem;
            border-radius: var(--radius);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 2rem;
            flex-shrink: 0;
        }

        .section-icon.news,
        .section-icon.start,
        .section-icon.platform,
        .section-icon.data,
        .section-icon.advanced,
        .section-icon.learn,
        .section-icon.info { background: var(--bg); }

        .section-title {
            font-size: 2.4rem;
            font-weight: 600;
            color: var(--primary);
            line-height: 2.8rem;
        }

        .section-subtitle {
            font-size: 1.5rem;
            font-weight: 400;
            color: var(--primary);
            opacity: 0.6;
            margin-top: 0.2rem;
        }

        /* ===== CARDS — matches 506.ai card style ===== */
        .cards-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(28rem, 1fr));
            gap: 2rem;
        }

        .card {
            background: var(--white);
            border-radius: var(--radius);
            padding: 2.8rem;
            border: 1px solid rgba(0,70,115,0.06);
            transition: var(--transition);
            cursor: pointer;
            display: flex;
            flex-direction: column;
        }
        .card:hover {
            box-shadow: var(--shadow);
            transform: translateY(-2px);
        }

        .card-icon {
            width: 4rem;
            height: 4rem;
            border-radius: var(--radius);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.8rem;
            margin-bottom: 1.6rem;
            background: var(--bg);
        }

        .card h3 {
            font-size: 1.8rem;
            font-weight: 600;
            color: var(--primary);
            margin-bottom: 0.8rem;
            line-height: 2.4rem;
        }

        .card p {
            font-size: 1.6rem;
            font-weight: 400;
            color: var(--primary);
            opacity: 0.75;
            line-height: 2.4rem;
            flex-grow: 1;
        }

        /* Link with animated underline — matches 506.ai style */
        .card-link {
            display: inline-flex;
            align-items: center;
            gap: 0.6rem;
            font-size: 1.6rem;
            font-weight: 600;
            color: var(--primary);
            margin-top: 1.8rem;
            background: linear-gradient(var(--primary), var(--primary));
            background-position: 100% 100%;
            background-repeat: no-repeat;
            background-size: 0 1px;
            transition: background-size 0.35s;
            padding-bottom: 2px;
        }
        .card:hover .card-link,
        .news-card:hover .card-link {
            background-position: 0 100%;
            background-size: 100% 1px;
        }

        .card-link .arrow {
            transition: transform 0.3s;
        }
        .card:hover .card-link .arrow,
        .news-card:hover .card-link .arrow { transform: translateX(4px); }

        /* ===== NEWS SECTION ===== */
        .news-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(30rem, 1fr));
            gap: 2rem;
        }

        .news-card {
            background: var(--white);
            border-radius: var(--radius);
            padding: 2.8rem;
            border: 1px solid rgba(0,70,115,0.06);
            transition: var(--transition);
            cursor: pointer;
            display: flex;
            flex-direction: column;
        }
        .news-card:hover { box-shadow: var(--shadow); transform: translateY(-2px); }

        .news-date {
            font-size: 1.4rem;
            font-weight: 500;
            color: var(--primary);
            opacity: 0.55;
            margin-bottom: 0.6rem;
        }

        .news-card h3 {
            font-size: 1.8rem;
            font-weight: 600;
            color: var(--primary);
            margin-bottom: 0.8rem;
            line-height: 2.4rem;
        }

        .news-card p {
            font-size: 1.6rem;
            font-weight: 400;
            color: var(--primary);
            opacity: 0.75;
            line-height: 2.4rem;
            flex-grow: 1;
        }

        .news-tag {
            display: inline-block;
            font-size: 1.3rem;
            font-weight: 600;
            padding: 0.3rem 1rem;
            border-radius: 2rem;
            margin-top: 1.4rem;
        }
        .news-tag.feature { background: rgba(170,208,132,0.2); color: #5a8a2e; }
        .news-tag.update { background: rgba(0,136,184,0.1); color: var(--primary-light); }

        .section-more {
            display: inline-flex;
            align-items: center;
            gap: 0.6rem;
            margin-top: 2rem;
            font-size: 1.4rem;
            font-weight: 600;
            color: var(--primary);
            cursor: pointer;
            background: linear-gradient(var(--primary), var(--primary));
            background-position: 100% 100%;
            background-repeat: no-repeat;
            background-size: 0 1px;
            transition: background-size 0.35s;
            padding-bottom: 2px;
        }
        .section-more:hover {
            background-position: 0 100%;
            background-size: 100% 1px;
        }

        /* ===== CONTACT BANNER ===== */
        .contact-banner {
            background: linear-gradient(90deg, #f0f7fb, #bee4fb);
            border-radius: var(--radius-lg);
            padding: 4rem 5rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
            margin-top: 5rem;
        }

        .contact-banner h3 {
            font-size: 2rem;
            font-weight: 600;
            color: var(--primary);
            margin-bottom: 0.4rem;
        }

        .contact-banner p {
            font-size: 1.5rem;
            font-weight: 400;
            color: var(--primary);
            opacity: 0.7;
        }

        /* ===== FOOTER ===== */
        .footer {
            margin-left: var(--sidebar-w);
            padding: 3rem 5rem;
            border-top: 1px solid rgba(0,70,115,0.06);
            display: flex;
            align-items: center;
            justify-content: space-between;
            font-size: 1.3rem;
            font-weight: 400;
            color: var(--gray-darker);
        }
        .footer-links { display: flex; gap: 2.4rem; }
        .footer-links a {
            color: var(--gray-darker);
            background: linear-gradient(var(--primary), var(--primary));
            background-position: 100% 100%;
            background-repeat: no-repeat;
            background-size: 0 1px;
            transition: background-size 0.35s, color 0.3s;
            padding-bottom: 1px;
        }
        .footer-links a:hover {
            color: var(--primary);
            background-position: 0 100%;
            background-size: 100% 1px;
        }

        /* ===== SUBPAGES ===== */
        .subpage { display: none; }
        .subpage.active { display: block; }

        .breadcrumb {
            display: flex;
            align-items: center;
            gap: 0.8rem;
            font-size: 1.6rem;
            color: var(--primary);
            opacity: 0.6;
            margin-bottom: 2.4rem;
            font-weight: 500;
            max-width: 1280px;
            margin-left: auto;
            margin-right: auto;
        }
        .breadcrumb a {
            color: var(--primary);
            font-weight: 500;
            background: linear-gradient(var(--primary), var(--primary));
            background-position: 100% 100%;
            background-repeat: no-repeat;
            background-size: 0 1px;
            transition: background-size 0.35s;
            padding-bottom: 1px;
        }
        .breadcrumb a:hover { background-position: 0 100%; background-size: 100% 1px; }

        .article {
            background: var(--white);
            border-radius: var(--radius-lg);
            padding: 5rem 6rem;
            border: 1px solid rgba(0,70,115,0.06);
            max-width: 1280px;
            margin-left: auto;
            margin-right: auto;
            box-shadow: var(--shadow-sm);
        }

        .article h1 {
            font-size: 3.6rem;
            font-weight: 700;
            color: var(--primary);
            line-height: 4.4rem;
            margin-bottom: 1rem;
        }

        .article .desc {
            font-size: 1.9rem;
            font-weight: 400;
            color: var(--primary);
            opacity: 0.75;
            margin-bottom: 3.2rem;
            line-height: 3rem;
        }

        .article h2 {
            font-size: 2.6rem;
            font-weight: 700;
            color: var(--primary);
            margin: 3.2rem 0 1.2rem;
            line-height: 3.4rem;
        }

        .article h3 {
            font-size: 2rem;
            font-weight: 600;
            color: var(--primary);
            margin: 2.4rem 0 1rem;
            line-height: 2.8rem;
        }

        .article p {
            font-size: 1.8rem;
            font-weight: 300;
            color: var(--primary);
            margin-bottom: 1.6rem;
            line-height: 3rem;
        }

        .article ul { margin: 1.2rem 0 2rem 2.4rem; }
        .article ol { margin: 1.2rem 0 2rem 2.4rem; }
        .article li {
            font-size: 1.8rem;
            font-weight: 300;
            color: var(--primary);
            margin-bottom: 0.8rem;
            line-height: 2.9rem;
        }
        .article li strong { font-weight: 600; }
        .article p strong { font-weight: 600; }
        .article strong { font-weight: 600; }

        #page-changelog .article h2 {
            border-top: 1px solid rgba(0,70,115,0.12);
            padding-top: 2.4rem;
        }
        #page-changelog .article h2:first-of-type {
            border-top: none;
            padding-top: 0;
        }

        .placeholder-img {
            width: 100%;
            height: 20rem;
            background: linear-gradient(90deg, var(--bg), var(--accent));
            border-radius: var(--radius);
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--gray-mid);
            font-size: 1.4rem;
            font-weight: 500;
            margin: 2rem 0;
        }

        .related {
            margin-top: 4rem;
            padding-top: 3.2rem;
            border-top: 1px solid rgba(0,70,115,0.06);
        }
        .related h3 {
            font-size: 1.8rem;
            font-weight: 700;
            color: var(--primary);
            margin-bottom: 1.2rem;
        }
        .related-list { display: flex; flex-direction: column; gap: 0.6rem; }
        .related-item {
            display: flex;
            align-items: center;
            gap: 0.8rem;
            padding: 1rem 1.4rem;
            border-radius: var(--radius);
            font-size: 1.8rem;
            font-weight: 500;
            color: var(--primary);
            cursor: pointer;
            transition: var(--transition);
        }
        .related-item:hover { background: var(--bg); }

        /* ===== RESPONSIVE ===== */
@media (max-width: 1024px) {
            .sidebar { width: 24rem; }
            .main, .footer { margin-left: 24rem; }
        }

        @media (max-width: 768px) {
            .menu-toggle { display: flex; }
            .header-cta { display: none; }
            .sidebar {
                width: 100%;
                left: 0;
                right: 0;
                border-right: none;
                border-left: none;
                transform: translateX(100%);
                transition: transform 0.28s ease;
            }
            body.menu-open .sidebar { transform: translateX(0); }
            .main, .footer { margin-left: 0; }
            .main-inner { padding: 2.4rem 2rem; }
            .hero { border-radius: 0 0 2rem 2rem; }
            .hero-inner { padding: 0 2rem; }
            .hero h1 { font-size: 2.6rem; line-height: 3.2rem; }
            .cards-grid, .news-grid { grid-template-columns: 1fr; }
            .contact-banner { flex-direction: column; align-items: flex-start; gap: 2rem; text-align: left; padding: 3rem; }
            .article { padding: 3rem; }
            .breadcrumb {
                flex-wrap: wrap;
                gap: 0.4rem 0.6rem;
                font-size: 1.3rem;
                line-height: 1.8rem;
            }
            .footer {
                flex-direction: column;
                align-items: flex-start;
                gap: 1.2rem;
                padding: 3rem 2rem;
                text-align: left;
            }
            .footer-links {
                flex-direction: column;
                align-items: flex-start;
                gap: 0.8rem;
            }
        }

/* === Multi-Page-Anpassungen === */
/* Mehr Abstand zwischen Fixed-Header und Breadcrumb auf den Subpages */
.main-inner .breadcrumb {
    margin-top: 3rem;
}

/* Footer-Text auf 15px (Default war 13px) */
.footer,
.footer-links a {
    font-size: 1.5rem;
}

/* === Mobile-Optimierungen === */
@media (max-width: 768px) {
    /* Lange Wörter wie "Nutzerberechtigungen" sauber umbrechen und Schriftgröße reduzieren */
    .article h1 {
        font-size: 2.8rem;
        line-height: 3.4rem;
        overflow-wrap: anywhere;
        word-break: break-word;
        hyphens: auto;
    }
    .article h2 {
        font-size: 2.2rem;
        line-height: 2.8rem;
        overflow-wrap: anywhere;
        hyphens: auto;
    }

    /* Inline-Grids in Artikeln (z. B. Kachel-Layouts auf "Ausgabeformate",
       "Dateien & Websiteinhalte", "Sprachmodelle", "Prompting") auf eine Spalte stacken */
    .article div[style*="display:grid"],
    .article div[style*="display: grid"] {
        grid-template-columns: 1fr !important;
    }

    /* Artikel-Innenpadding etwas reduzieren, damit Inhalt nicht abgeschnitten wirkt */
    .article { padding: 2.4rem 1.8rem; }

    /* Lange URLs/Links (z. B. Modelcard-Links auf "Sprachmodelle") umbrechen,
       damit sie nicht über den rechten Rand hinauslaufen */
    .article a {
        overflow-wrap: anywhere;
        word-break: break-word;
    }
    .article li, .article p { overflow-wrap: anywhere; }
}