@import url('https://fonts.googleapis.com/css2?family=Lexend:wght@500;600;700&family=Source+Sans+Pro:wght@400;600&display=swap');

:root {
    --primary: #0f766e;
    --secondary: #1e293b;
    --accent: #eab308;
    --background: #f0fdfa;
    --surface: #ffffff;
    --card: #ccfbf1;
    --text: #134e4a;
    --muted: #64748b;
    --danger: #dc2626;
    --success: #16a34a;

    --font-headings: 'Lexend', sans-serif;
    --font-body: 'Source Sans Pro', sans-serif;
    --border-radius: 6px;
}

/* --- GRUNDLAGEN & UTILITIES --- */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 2rem;
}

body {
    font-family: var(--font-body);
    font-size: 1rem;
    line-height: 1.75;
    color: var(--text);
    background-color: var(--background);
}

h1, h2, h3 {
    font-family: var(--font-headings);
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 1rem;
}

h1 { font-size: 2.625rem; }
h2 { font-size: 1.75rem; margin-top: 2.5rem; margin-bottom: 1.5rem; }
h3 { font-size: 1.25rem; }

p { margin-bottom: 1rem; }
a { color: var(--primary); text-decoration: none; transition: color 0.3s ease; }
a:hover { color: var(--accent); }
ul { list-style: none; }
img { max-width: 100%; height: auto; display: block; }

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    font-family: var(--font-headings);
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.btn-primary {
    background-color: var(--accent);
    color: var(--secondary);
}
.btn-primary:hover {
    background-color: #d9a207;
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary);
    border-color: var(--primary);
}
.btn-secondary:hover {
    background-color: var(--primary);
    color: white;
}

.success { color: var(--success); }
.danger { color: var(--danger); }
.warning { color: var(--accent); }
.muted { color: var(--muted); }

/* --- HEADER --- */
.header {
    background-color: var(--surface);
    padding: 1.5rem 0;
    border-bottom: 1px solid #e2e8f0;
}
.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.logo {
    display: flex;
    align-items: center;
    font-family: var(--font-headings);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text);
}
.logo-icon {
    font-size: 1.8rem;
    color: var(--primary);
    margin-right: 0.5rem;
}
.main-nav ul {
    display: flex;
    gap: 2rem;
}
.main-nav a {
    font-weight: 600;
    color: var(--muted);
    position: relative;
}
.main-nav a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary);
    transition: width 0.3s ease;
}
.main-nav a:hover::after {
    width: 100%;
}

/* --- SECTIONS --- */
section {
    padding: 4rem 0;
}

/* Sektion 1: Hero */
.hero {
    background-image:
        linear-gradient(rgba(240, 253, 250, 0.95), rgba(240, 253, 250, 0.95)),
        url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ccfbf1' fill-opacity='0.4'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    padding-top: 5rem;
    padding-bottom: 5rem;
}
.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}
.hero .subtitle {
    font-size: 1.1rem;
    color: var(--muted);
}
.hero-buttons {
    margin-top: 2rem;
    display: flex;
    gap: 1rem;
}
.hero-image img {
    border-radius: var(--border-radius);
    box-shadow: 0 10px 25px rgba(15, 118, 110, 0.1);
}

/* Sektion 2: Warn-Karten */
.section-why-important { background-color: var(--surface); text-align: center; }
.warning-cards-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 2rem;
}
.warning-card {
    background-color: var(--background);
    padding: 2rem;
    border-radius: var(--border-radius);
    border: 2px solid var(--card);
}
.warning-card .value {
    font-family: var(--font-headings);
    font-size: 2.5rem;
    color: var(--primary);
    margin-bottom: 0.5rem;
}
.explanation-text {
    max-width: 800px;
    margin: 3rem auto 0;
    text-align: left;
}

/* Sektion 3: Kreditarten */
.section-kreditarten { background-color: var(--card); }
.kreditarten-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}
.kreditart-card {
    background-color: var(--surface);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--primary);
    border-left: 5px solid var(--primary);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.kreditart-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(15, 118, 110, 0.1);
}
.kreditart-card .icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}
.kreditart-card ul {
    padding-left: 1.2rem;
    list-style: '✓ ';
}
.kreditart-card li { padding-left: 0.5rem; color: var(--muted); }

/* Sektion 4: Effektivzins */
.section-effektivzins { background-color: var(--surface); }
.section-container-split {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}
.example-table-wrapper {
    background-color: var(--card);
    padding: 1.5rem;
    border-radius: var(--border-radius);
}
table {
    width: 100%;
    border-collapse: collapse;
}
th, td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid var(--primary);
}
th { font-family: var(--font-headings); color: var(--primary); }
tbody tr:nth-child(even) { background-color: #e6f6f5; }
.fazit-row { background-color: var(--surface); }
.table-conclusion { margin-top: 1rem; text-align: center; font-weight: 600; }

/* Sektion 5: Rechner */
.section-rechner { background-color: var(--card); }
.rechner-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    background-color: var(--surface);
    padding: 2rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--primary);
}
.form-group { margin-bottom: 1.5rem; }
.form-group label { display: block; font-weight: 600; margin-bottom: 0.5rem; }
input[type="range"] {
    width: 100%;
    -webkit-appearance: none;
    appearance: none;
    height: 8px;
    background: var(--card);
    outline: none;
    border-radius: 5px;
}
input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    background: var(--primary);
    cursor: pointer;
    border-radius: 50%;
}
select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--primary);
    border-radius: var(--border-radius);
    font-size: 1rem;
}
.rechner-output {
    background-color: var(--secondary);
    color: white;
    padding: 2rem;
    border-radius: var(--border-radius);
    display: flex;
    flex-direction: column;
    justify-content: center;
}
.output-item {
    display: flex;
    justify-content: space-between;
    padding: 1rem 0;
    border-bottom: 1px solid var(--muted);
}
.output-item:last-child { border-bottom: none; }
.output-value {
    font-family: var(--font-headings);
    font-size: 1.5rem;
    color: var(--accent);
}
.info-text { font-size: 0.9rem; color: var(--muted); }

/* Sektion 6: RSV */
.section-rsv { background-color: var(--surface); }
.warning-box {
    background-color: #fef2f2;
    border: 1px solid var(--danger);
    border-left: 5px solid var(--danger);
    padding: 1.5rem;
    margin: 1.5rem 0;
    border-radius: var(--border-radius);
}
.warning-box p { color: var(--danger); font-weight: 600; margin: 0; }
.checklist { margin-top: 1.5rem; }
.checklist li { margin-bottom: 0.5rem; font-weight: 600; }
.item-good { color: var(--success); }
.item-bad { color: var(--danger); }

/* Sektion 7: Schufa */
.section-schufa { background-color: var(--card); }
.schufa-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 2rem;
    align-items: center;
}
.tipps-box {
    background-color: var(--surface);
    border: 1px solid var(--success);
    border-left: 5px solid var(--success);
    padding: 1.5rem;
    margin-top: 2rem;
    border-radius: var(--border-radius);
}
.tipps-box p { margin: 0; }

/* Sektion 8: Sondertilgung */
.section-sondertilgung { background-color: var(--surface); }
.sondertilgung-columns {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}
.sondertilgung-columns .column {
    background-color: var(--background);
    padding: 1.5rem;
    border-radius: var(--border-radius);
}
.sondertilgung-columns ul { list-style: '→ '; padding-left: 1rem; }
.sondertilgung-columns li { padding-left: 0.5rem; margin-bottom: 0.5rem; }
.intro-text { max-width: 800px; }
.info-box {
    background-color: #fffbeb;
    border: 1px solid var(--accent);
    padding: 1.5rem;
    margin-top: 2rem;
    border-radius: var(--border-radius);
}

/* Sektion 9: KI */
.section-ki { background-color: var(--card); }
.ki-cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}
.ki-card {
    background-color: var(--surface);
    padding: 1.5rem;
    text-align: center;
    border-radius: var(--border-radius);
    border: 1px solid var(--primary);
}
.ki-card .icon { font-size: 2.5rem; margin-bottom: 1rem; }
.ki-card h3 { margin-bottom: 0.5rem; }

/* Sektion 10: Tipps */
.section-tipps { background-color: var(--surface); }
.steps-list {
    counter-reset: step-counter;
    list-style: none;
    max-width: 800px;
    margin: 0 auto;
}
.steps-list li {
    counter-increment: step-counter;
    position: relative;
    padding-left: 3.5rem;
    margin-bottom: 2rem;
}
.steps-list li::before {
    content: counter(step-counter);
    position: absolute;
    left: 0;
    top: -5px;
    font-family: var(--font-headings);
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary);
    background-color: var(--card);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}
.steps-list h3 { margin-bottom: 0.25rem; }
.steps-list p { color: var(--muted); margin: 0; }

/* Sektion 11: Fehler */
.section-fehler { background-color: var(--card); }
.fehler-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}
.fehler-card {
    background-color: var(--surface);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--danger);
}
.fehler-card h3 { color: var(--danger); }

/* Sektion 12: Baufinanzierung */
.section-baufinanzierung { background-color: var(--surface); }
.section-baufinanzierung p { max-width: 800px; }
.section-baufinanzierung .example-table-wrapper { max-width: 800px; }

/* Sektion 13: FAQ */
.section-faq { background-color: var(--card); }
.faq-accordion { max-width: 800px; margin: 0 auto; }
.faq-item {
    background-color: var(--surface);
    border: 1px solid var(--primary);
    border-radius: var(--border-radius);
    margin-bottom: 1rem;
}
.faq-question {
    width: 100%;
    background: none;
    border: none;
    text-align: left;
    padding: 1rem 1.5rem;
    font-family: var(--font-headings);
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    position: relative;
    color: var(--text);
}
.faq-question::after {
    content: '+';
    position: absolute;
    right: 1.5rem;
    font-size: 1.5rem;
    transition: transform 0.3s ease;
}
.faq-item.active .faq-question::after {
    transform: rotate(45deg);
}
.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease-out, padding 0.4s ease-out;
}
.faq-answer p {
    padding: 0 1.5rem 1.5rem;
    margin: 0;
    color: var(--muted);
}
.faq-item.active .faq-answer {
    max-height: 300px;
}

/* Sektion 14: Kontakt */
.section-kontakt { background-color: var(--surface); }
.kontakt-container {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 3rem;
}
.kontakt-info a { font-weight: 600; }
.kontakt-form label { display: block; margin-bottom: 0.25rem; font-weight: 600; }
.kontakt-form input, .kontakt-form select, .kontakt-form textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--muted);
    border-radius: var(--border-radius);
    font-family: var(--font-body);
    font-size: 1rem;
}
.kontakt-form input:focus, .kontakt-form select:focus, .kontakt-form textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--card);
}
.form-group-checkbox {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}
.form-group-checkbox input { width: auto; }
.form-group-checkbox label { margin-bottom: 0; font-weight: normal; }
.kontakt-form button { width: 100%; margin-top: 1rem; }

/* Sektion 15: Footer */
.footer {
    background-color: var(--secondary);
    color: var(--surface);
    padding: 4rem 0 0;
}
.footer-container {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 2rem;
    padding-bottom: 3rem;
    border-bottom: 1px solid var(--muted);
}
.logo-footer {
    color: white;
    font-size: 1.3rem;
    display: block;
    margin-bottom: 1rem;
}
.footer-col h4 {
    font-family: var(--font-headings);
    margin-bottom: 1rem;
    color: var(--accent);
}
.footer-col a {
    color: #e2e8f0;
    display: block;
    margin-bottom: 0.5rem;
}
.footer-col a:hover { color: white; }
.footer-bottom {
    padding: 1.5rem 0;
    text-align: center;
}
.footer-bottom p {
    margin: 0;
    font-size: 0.9rem;
    color: var(--muted);
}
.footer-bottom p:first-child { color: white; margin-bottom: 0.5rem; }

/* --- RESPONSIVE DESIGN --- */
@media (max-width: 1024px) {
    h1 { font-size: 2.25rem; }
    h2 { font-size: 1.5rem; }
    .header .main-nav { display: none; } /* Simplified for demo */
    .cta-header { font-size: 0.9rem; padding: 0.5rem 1rem; }
    .hero-container { grid-template-columns: 1fr; text-align: center; }
    .hero-image { order: -1; max-width: 500px; margin: 0 auto; }
    .hero-buttons { justify-content: center; }
    .warning-cards-grid { grid-template-columns: 1fr; }
    .section-container-split, .schufa-content, .sondertilgung-columns, .kontakt-container {
        grid-template-columns: 1fr;
    }
    .rechner-wrapper { grid-template-columns: 1fr; }
    .footer-container { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
    section { padding: 3rem 0; }
    .footer-container { grid-template-columns: 1fr; }
    .footer-col { text-align: center; }
    .footer-bottom { text-align: center; }
    .footer-bottom p { margin-bottom: 0.5rem; }
}