:root {
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary: #0f172a;
    --background: #f8fafc;
    --card-bg: #ffffff;
    --text-dark: #0f172a;
    --text-primary: #334155;
    --text-secondary: #64748b;
    --border: #e2e8f0;
    --success: #10b981;
    --accent: #f97316;
}

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

body {
    font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--background);
    color: var(--text-primary);
    line-height: 1.5;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Header & Nav */
.header {
    background-color: var(--card-bg);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--text-dark);
}

.logo-icon {
    font-size: 1.4rem;
    color: var(--primary);
}

.nav {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    padding: 0.65rem 1.25rem;
    border-radius: 8px;
    font-size: 0.88rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s ease-in-out;
    border: none;
}

.btn-secondary {
    background-color: #f1f5f9;
    color: var(--text-dark);
}

.btn-secondary:hover {
    background-color: #e2e8f0;
    transform: translateY(-2px);
}

/* Cards */
.card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2rem;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05);
}

/* Interactive Layout Grid */
.calc-layout {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 2rem;
    align-items: stretch;
}

@media (max-width: 900px) {
    .calc-layout {
        grid-template-columns: 1fr;
    }
}

/* Sliders */
.slider-group {
    margin-bottom: 2rem;
}

.slider-group:last-child {
    margin-bottom: 0;
}

.slider-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
    font-weight: 700;
    font-size: 0.9rem;
    color: var(--text-dark);
}

.slider-val {
    color: var(--primary);
    background: #eff6ff;
    padding: 0.2rem 0.6rem;
    border-radius: 6px;
    font-size: 0.8rem;
}

input[type="range"] {
    width: 100%;
    height: 6px;
    background: var(--border);
    border-radius: 9999px;
    outline: none;
    -webkit-appearance: none;
    appearance: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary);
    cursor: pointer;
    transition: transform 0.1s;
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

/* Ledger Rows */
.ledger-row {
    display: flex;
    justify-content: space-between;
    padding: 0.85rem 0;
    border-bottom: 1px dashed #334155;
    font-size: 0.85rem;
}

.ledger-row:last-child {
    border-bottom: none;
}

/* Info Cards Grid */
.info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.info-card {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    transition: transform 0.2s;
}

.info-card:hover {
    transform: translateY(-4px);
}

.info-icon {
    width: 48px;
    height: 48px;
    background: #dbeafe;
    color: var(--primary);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
}

.info-card h3 {
    font-size: 1.1rem;
    font-weight: 800;
    color: var(--text-dark);
}

.info-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.badge {
    display: inline-flex;
    padding: 0.25rem 0.6rem;
    border-radius: 9999px;
    font-size: 0.7rem;
    font-weight: 800;
    text-transform: uppercase;
    width: fit-content;
}

.badge-blue {
    background: #dbeafe;
    color: #1e40af;
}

/* Footer */
.footer {
    padding: 3rem 0;
    background: var(--secondary);
    margin-top: 8rem;
}