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

:root {
    --primary: #1a365d;
    --primary-mid: #2b5797;
    --primary-light: #edf2f7;
    --accent: #16a34a;
    --accent-dark: #15803d;
    --accent-light: #f0fdf4;
    --surface: #ffffff;
    --surface-glass: rgba(255, 255, 255, 0.72);
    --bg: #f0f4f8;
    --text: #1e293b;
    --text-muted: #64748b;
    --text-light: #94a3b8;
    --border: #e2e8f0;
    --warning-bg: #fffbeb;
    --warning-border: #f59e0b;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
    --shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.08);
    --radius: 12px;
    --radius-sm: 8px;
    --max-width: 860px;
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text);
    background: var(--bg);
    padding: 0 1rem;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ---- Header ---- */
header {
    text-align: center;
    padding: 2.5rem 1rem 1.5rem;
    max-width: var(--max-width);
    margin: 0 auto;
}

header h1 {
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-mid) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.35rem;
}

header .subtitle {
    color: var(--text-muted);
    font-size: 0.95rem;
    font-weight: 400;
}

main {
    max-width: var(--max-width);
    margin: 0 auto;
    padding-bottom: 2rem;
}

/* ---- Disclaimer ---- */
.disclaimer {
    background: var(--warning-bg);
    border-left: 4px solid var(--warning-border);
    padding: 0.85rem 1.15rem;
    margin-bottom: 1.75rem;
    border-radius: var(--radius-sm);
    font-size: 0.84rem;
    color: #92400e;
    line-height: 1.65;
}

/* ---- Form ---- */
.input-section {
    background: var(--surface);
    padding: 1.75rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin-bottom: 1.75rem;
    border: 1px solid var(--border);
}

.form-group {
    margin-bottom: 1.15rem;
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.3rem;
    color: var(--primary);
    font-size: 0.88rem;
    letter-spacing: -0.01em;
}

.form-group .hint {
    font-size: 0.78rem;
    color: var(--text-muted);
    margin-bottom: 0.4rem;
}

.input-row {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.input-row input[type="number"] {
    flex: 0 0 180px;
}

.input-row input[type="range"] {
    flex: 1;
}

input[type="number"],
select {
    width: 100%;
    max-width: 300px;
    padding: 0.6rem 0.85rem;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 0.95rem;
    font-family: inherit;
    background: var(--surface);
    color: var(--text);
    transition: border-color var(--transition), box-shadow var(--transition);
}

input[type="number"]:focus,
select:focus {
    outline: none;
    border-color: var(--primary-mid);
    box-shadow: 0 0 0 3px rgba(43, 87, 151, 0.12);
}

/* Range slider */
input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    height: 6px;
    background: linear-gradient(90deg, var(--primary-mid), var(--accent));
    border-radius: 3px;
    cursor: pointer;
    opacity: 0.7;
    transition: opacity var(--transition);
}

input[type="range"]:hover {
    opacity: 1;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 20px;
    height: 20px;
    background: var(--surface);
    border: 2px solid var(--primary-mid);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.15);
    transition: transform var(--transition), box-shadow var(--transition);
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.15);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

input[type="range"]::-moz-range-thumb {
    width: 20px;
    height: 20px;
    background: var(--surface);
    border: 2px solid var(--primary-mid);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.15);
}

/* Checkboxes */
.checkbox-group {
    display: flex;
    align-items: center;
    gap: 0.6rem;
}

.checkbox-group input[type="checkbox"] {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border: 2px solid var(--border);
    border-radius: 5px;
    cursor: pointer;
    position: relative;
    transition: background var(--transition), border-color var(--transition);
    flex-shrink: 0;
}

.checkbox-group input[type="checkbox"]:checked {
    background: var(--primary-mid);
    border-color: var(--primary-mid);
}

.checkbox-group input[type="checkbox"]:checked::after {
    content: "";
    position: absolute;
    left: 5px;
    top: 2px;
    width: 6px;
    height: 10px;
    border: solid #fff;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

.checkbox-group label {
    font-weight: 500;
    color: var(--text);
    font-size: 0.9rem;
    cursor: pointer;
    margin-bottom: 0;
}

.bundesland-group {
    overflow: hidden;
    max-height: 0;
    opacity: 0;
    transition: max-height 0.35s ease, opacity 0.35s ease, margin 0.35s ease;
    margin-top: 0;
}

.bundesland-group.visible {
    max-height: 80px;
    opacity: 1;
    margin-top: 1rem;
}

.btn-berechnen {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-mid) 100%);
    color: #fff;
    border: none;
    padding: 0.7rem 2.25rem;
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
    cursor: pointer;
    margin-top: 0.5rem;
    transition: transform var(--transition), box-shadow var(--transition);
    letter-spacing: -0.01em;
}

.btn-berechnen:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(26, 54, 93, 0.25);
}

.btn-berechnen:active {
    transform: translateY(0);
}

/* ---- Results ---- */
.results-section {
    display: none;
    animation: fadeSlideIn 0.4s ease both;
}

.results-section.visible {
    display: block;
}

@keyframes fadeSlideIn {
    from { opacity: 0; transform: translateY(12px); }
    to { opacity: 1; transform: translateY(0); }
}

.comparison-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 1rem;
}

.result-card {
    background: var(--surface);
    padding: 1.35rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    border-top: 3px solid var(--primary);
    transition: transform var(--transition), box-shadow var(--transition);
}

.result-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.result-card.linnemann {
    border-top-color: var(--accent);
}

.result-card h3 {
    font-size: 0.95rem;
    font-weight: 700;
    margin-bottom: 0.85rem;
    color: var(--primary);
    letter-spacing: -0.01em;
}

.result-card.linnemann h3 {
    color: var(--accent-dark);
}

.result-row {
    display: flex;
    justify-content: space-between;
    padding: 0.35rem 0;
    font-size: 0.88rem;
}

.result-row.total {
    border-top: 2px solid var(--border);
    margin-top: 0.6rem;
    padding-top: 0.65rem;
    font-weight: 700;
    font-size: 1rem;
}

.result-row .label {
    color: var(--text-muted);
}

.result-row .value {
    font-variant-numeric: tabular-nums;
    font-weight: 500;
}

.result-row.rate {
    font-size: 0.78rem;
    color: var(--text-light);
}

/* Savings banner */
.savings-banner {
    background: linear-gradient(135deg, #ecfdf5 0%, #d1fae5 100%);
    border: 1.5px solid var(--accent);
    border-radius: var(--radius);
    padding: 1.15rem 1.5rem;
    text-align: center;
    margin-bottom: 1.5rem;
    position: relative;
    overflow: hidden;
}

.savings-banner::before {
    content: "";
    position: absolute;
    top: -50%;
    right: -20%;
    width: 200px;
    height: 200px;
    background: radial-gradient(circle, rgba(22, 163, 74, 0.08) 0%, transparent 70%);
    pointer-events: none;
}

.savings-banner .amount {
    font-size: 1.6rem;
    font-weight: 800;
    color: var(--accent-dark);
    letter-spacing: -0.02em;
}

.savings-banner .detail {
    font-size: 0.84rem;
    color: var(--text-muted);
    margin-top: 0.3rem;
}

.savings-banner .raise-equivalent {
    margin-top: 0.65rem;
    padding-top: 0.6rem;
    border-top: 1px solid rgba(22, 163, 74, 0.18);
    font-size: 0.84rem;
    color: var(--text-muted);
    line-height: 1.55;
}

.savings-banner .raise-equivalent strong {
    color: var(--accent-dark);
    font-weight: 700;
}

.no-change {
    background: linear-gradient(135deg, #f8fafc 0%, var(--primary-light) 100%);
    border-color: var(--primary-mid);
}

.no-change::before {
    background: radial-gradient(circle, rgba(43, 87, 151, 0.06) 0%, transparent 70%);
}

.no-change .amount {
    color: var(--primary);
    font-size: 1.1rem;
    font-weight: 700;
}

/* ---- Chart ---- */
.chart-section {
    display: none;
    background: var(--surface);
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    margin-bottom: 1.75rem;
    animation: fadeSlideIn 0.4s ease both;
    animation-delay: 0.1s;
}

.chart-section.visible {
    display: block;
}

.chart-section h3 {
    font-size: 0.95rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 0.85rem;
    letter-spacing: -0.01em;
}

canvas {
    width: 100%;
    height: auto;
    border-radius: var(--radius-sm);
}

/* ---- Explanation ---- */
.explanation-section {
    margin-top: 1rem;
}

.explanation-section details {
    background: var(--surface);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    margin-bottom: 0.6rem;
    border: 1px solid var(--border);
    transition: box-shadow var(--transition);
}

.explanation-section details[open] {
    box-shadow: var(--shadow);
}

.explanation-section summary {
    padding: 0.85rem 1.15rem;
    font-weight: 600;
    color: var(--primary);
    cursor: pointer;
    font-size: 0.88rem;
    letter-spacing: -0.01em;
    list-style: none;
    display: flex;
    align-items: center;
    gap: 0.6rem;
}

.explanation-section summary::-webkit-details-marker {
    display: none;
}

.explanation-section summary::before {
    content: "";
    display: inline-block;
    width: 6px;
    height: 6px;
    border-right: 2px solid var(--primary-mid);
    border-bottom: 2px solid var(--primary-mid);
    transform: rotate(-45deg);
    transition: transform var(--transition);
    flex-shrink: 0;
}

details[open] > summary::before {
    transform: rotate(45deg);
}

.explanation-section .detail-content {
    padding: 0 1.15rem 1.15rem;
    font-size: 0.84rem;
    color: var(--text-muted);
    line-height: 1.75;
}

.explanation-section .detail-content p + p {
    margin-top: 0.5rem;
}

.explanation-section code {
    background: var(--primary-light);
    padding: 0.15rem 0.4rem;
    border-radius: 4px;
    font-size: 0.8rem;
    color: var(--primary);
}

/* ---- Cookie banner ---- */
.cookie-banner {
    position: fixed;
    bottom: 1rem;
    left: 50%;
    transform: translateX(-50%);
    max-width: 600px;
    width: calc(100% - 2rem);
    background: var(--surface-glass);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    color: var(--text);
    padding: 0.85rem 1.25rem;
    font-size: 0.82rem;
    border-radius: var(--radius);
    z-index: 100;
    box-shadow: var(--shadow-lg), 0 0 0 1px rgba(0, 0, 0, 0.04);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    line-height: 1.5;
    animation: slideUp 0.4s ease both;
    animation-delay: 0.5s;
}

@keyframes slideUp {
    from { opacity: 0; transform: translateX(-50%) translateY(20px); }
    to { opacity: 1; transform: translateX(-50%) translateY(0); }
}

.cookie-banner.hidden {
    display: none;
}

.cookie-banner .cookie-icon {
    font-size: 1.2rem;
    flex-shrink: 0;
}

.cookie-banner .cookie-text {
    flex: 1;
}

.cookie-close {
    background: var(--primary-light);
    border: none;
    color: var(--primary);
    font-size: 0.78rem;
    font-weight: 600;
    cursor: pointer;
    padding: 0.4rem 0.85rem;
    border-radius: 6px;
    white-space: nowrap;
    transition: background var(--transition);
    flex-shrink: 0;
    font-family: inherit;
}

.cookie-close:hover {
    background: #dbeafe;
}

/* ---- Footer ---- */
footer {
    max-width: var(--max-width);
    margin: 1.5rem auto 2.5rem;
    padding-top: 1.25rem;
    border-top: 1px solid var(--border);
    text-align: center;
    font-size: 0.8rem;
    color: var(--text-light);
}

footer p {
    margin-bottom: 0.4rem;
}

footer .footer-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-top: 0.5rem;
}

footer a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color var(--transition);
    font-weight: 500;
}

footer a:hover {
    color: var(--primary);
}

/* ---- Impressum ---- */
.impressum {
    display: none;
    text-align: left;
    background: var(--surface);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    padding: 1.5rem;
    margin-top: 1.25rem;
    font-size: 0.84rem;
    color: var(--text-muted);
    line-height: 1.75;
    animation: fadeSlideIn 0.3s ease both;
}

.impressum.visible {
    display: block;
}

.impressum h4 {
    color: var(--primary);
    margin-top: 1.25rem;
    margin-bottom: 0.35rem;
    font-size: 0.88rem;
    font-weight: 700;
    letter-spacing: -0.01em;
}

.impressum h4:first-child {
    margin-top: 0;
}

.impressum address {
    font-style: normal;
}

/* ---- Responsive ---- */
@media (max-width: 600px) {
    header h1 {
        font-size: 1.5rem;
    }

    header {
        padding: 1.75rem 0.5rem 1rem;
    }

    .input-section {
        padding: 1.25rem;
    }

    .comparison-grid {
        grid-template-columns: 1fr;
    }

    .input-row {
        flex-direction: column;
        align-items: stretch;
    }

    .input-row input[type="number"] {
        flex: auto;
        max-width: 100%;
    }

    .savings-banner .amount {
        font-size: 1.3rem;
    }

    .cookie-banner {
        bottom: 0.5rem;
        flex-direction: column;
        text-align: center;
        gap: 0.5rem;
    }

    .cookie-banner .cookie-icon {
        display: none;
    }
}