/* --- THEME COLORS --- */
:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --success-color: #28a745;

    /* Dark Mode Defaults */
    --bg-color: #121212;
    --surface-color: #1e1e1e;
    --text-color: #e0e0e0;
    --text-muted: #a0a0a0;
    --border-color: #333;
    --chart-border: #1e1e1e;
}

body.light-mode {
    --bg-color: #f4f7f6;
    --surface-color: #ffffff;
    --text-color: #1c1c1c;
    --text-muted: #555;
    --border-color: #e0e0e0;
    --chart-border: #ffffff;
}

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

body {
    font-family: 'Poppins', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    transition: background-color 0.3s, color 0.3s;
    overflow-x: hidden;
}

/* --- SIDEBAR --- */
.sidebar {
    width: 260px;
    background-color: var(--surface-color);
    padding: 2rem 1rem;
    height: 100vh;
    border-right: 1px solid var(--border-color);
    position: fixed;
    z-index: 100;
    transition: transform 0.3s ease-in-out, background-color 0.3s;
    left: 0;
}

.logo {
    text-align: center;
    margin-bottom: 2.5rem;
    font-weight: 700;
    font-size: 2rem;
    color: var(--primary-color);
}

.menu-item {
    display: block;
    padding: 1rem;
    margin-bottom: 0.5rem;
    border-radius: 8px;
    text-decoration: none;
    color: var(--text-muted);
    transition: background-color 0.3s, color 0.3s;
    font-weight: 500;
}

.menu-item .icon { margin-right: 1rem; }
.menu-item:hover {
    background-color: rgba(0, 123, 255, 0.1);
    color: var(--primary-color);
}
.menu-item.active {
    background-color: var(--primary-color);
    color: #fff;
    font-weight: 600;
}

/* --- MAIN CONTENT --- */
.main-content {
    margin-left: 260px;
    flex-grow: 1;
    padding: 2rem 3rem;
    transition: margin-left 0.3s ease-in-out;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.header-title h2 { font-size: 2.2rem; font-weight: 600; margin-bottom: 0.2rem; }
.header-title p { color: var(--text-muted); font-size: 1.1rem; }
.header-actions { display: flex; align-items: center; gap: 1.5rem; }

#comparisonToggleBtn {
    padding: 0.6rem 1.2rem;
    background-color: var(--secondary-color);
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    transition: background-color 0.3s;
}
#comparisonToggleBtn:hover { background-color: #5a6268; }


.calculator-container { display: grid; grid-template-columns: 1fr 1fr; gap: 3rem; }
.calculator { background-color: var(--surface-color); padding: 2rem; border-radius: 12px; border: 1px solid var(--border-color); transition: background-color 0.3s; }
.calculator h4 { margin-bottom: 1.5rem; font-size: 1.3rem; font-weight: 600; }
.input-group { margin-bottom: 2rem; }
.input-group:last-child { margin-bottom: 0; }


.label-container { display: flex; justify-content: space-between; align-items: center; margin-bottom: 1rem; }
.label-container label { font-weight: 500; color: var(--text-muted); }
.label-container input[type="number"], .input-group input[type="number"] { background-color: var(--bg-color); border: 1px solid var(--border-color); color: var(--text-color); padding: 0.5rem; border-radius: 6px; width: 120px; text-align: right; font-size: 1rem; }
.input-group input[type="number"] { width: 100%; text-align: left; }

input[type="range"] { -webkit-appearance: none; width: 100%; height: 8px; background: var(--bg-color); border-radius: 5px; outline: none; margin-top: 1rem; }
input[type="range"]::-webkit-slider-thumb { -webkit-appearance: none; appearance: none; width: 20px; height: 20px; background: var(--primary-color); cursor: pointer; border-radius: 50%; border: 3px solid var(--surface-color); }
input[type="range"]::-moz-range-thumb { width: 20px; height: 20px; background: var(--primary-color); cursor: pointer; border-radius: 50%; border: 3px solid var(--surface-color); }

#calculateBtn, #calculateCompBtn { display: block; width: 100%; margin-top: 2rem; padding: 1rem; font-size: 1.1rem; font-weight: 600; background-color: var(--primary-color); color: #fff; border: none; border-radius: 8px; cursor: pointer; transition: background-color 0.3s, transform 0.1s; }
#calculateBtn:hover, #calculateCompBtn:hover { background-color: #0069d9; }
#calculateBtn:active, #calculateCompBtn:active { transform: scale(0.98); }


.results-container { opacity: 0; transform: translateY(20px); transition: opacity 0.5s ease-out, transform 0.5s ease-out; }
.results-container.show { opacity: 1; transform: translateY(0); }

.results-summary { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; margin-bottom: 2rem; text-align: center; }
.result-item { background-color: var(--surface-color); padding: 1.5rem; border-radius: 8px; transition: background-color 0.3s; }
.result-item p { color: var(--text-muted); margin-bottom: 0.5rem; }
.result-item h3 { font-size: 1.8rem; font-weight: 600; color: var(--primary-color); }

.prepayment-results {
    background-color: rgba(40, 167, 69, 0.1);
    color: #28a745;
    padding: 1rem;
    border-radius: 8px;
    margin: 1.5rem 0;
    border: 1px solid rgba(40, 167, 69, 0.2);
}
.prepayment-results h4 { margin-bottom: 0.5rem; }
.prepayment-results p { font-size: 1rem; }


.chart-container { background-color: var(--surface-color); padding: 1.5rem; border-radius: 8px; transition: background-color 0.3s; height: 300px; }

#viewScheduleBtn, .pdf-button { margin-top: 1rem; width: 100%; padding: 0.8rem; border-radius: 8px; cursor: pointer; transition: background-color 0.3s, color 0.3s; }
#viewScheduleBtn { background: transparent; border: 1px solid var(--secondary-color); color: var(--secondary-color); }
#viewScheduleBtn:hover { background-color: var(--secondary-color); color: #fff; }

/* --- LOAN COMPARISON --- */
.comparison-container {
    background-color: var(--surface-color);
    padding: 2rem;
    border-radius: 12px;
}
.comparison-container h3 { text-align: center; font-size: 1.8rem; margin-bottom: 2rem; }
.comparison-calculators { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; }
.comparison-results table { width: 100%; border-collapse: collapse; margin-top: 2rem; }
.comparison-results th, .comparison-results td { padding: 1rem; text-align: center; border-bottom: 1px solid var(--border-color); }
.comparison-results th { font-weight: 600; color: var(--text-muted); }
.comparison-results tbody tr:last-child td { border-bottom: none; }
.comparison-results td:not(:first-child) { font-weight: 500; font-size: 1.2rem; }


/* --- THEME SWITCHER --- */
.switch { position: relative; display: inline-block; width: 50px; height: 28px; }
.switch input { opacity: 0; width: 0; height: 0; }
.slider { position: absolute; cursor: pointer; top: 0; left: 0; right: 0; bottom: 0; background-color: #ccc; transition: .4s; }
.slider:before { position: absolute; content: ""; height: 20px; width: 20px; left: 4px; bottom: 4px; background-color: white; transition: .4s; }
.slider.round { border-radius: 34px; }
.slider.round:before { border-radius: 50%; }
input:checked + .slider { background-color: var(--primary-color); }
input:checked + .slider:before { transform: translateX(22px); }

/* --- MODAL --- */
.modal { display: none; position: fixed; z-index: 1000; left: 0; top: 0; width: 100%; height: 100%; overflow: auto; background-color: rgba(0,0,0,0.7); animation: fadeIn 0.3s; }
.modal-content { background-color: var(--surface-color); margin: 5% auto; padding: 2rem; border: 1px solid var(--border-color); width: 80%; max-width: 800px; border-radius: 12px; position: relative; animation: slideIn 0.4s; }
.close-button { color: #aaa; position: absolute; top: 1rem; right: 1.5rem; font-size: 28px; font-weight: bold; cursor: pointer; }
.table-container { max-height: 60vh; overflow-y: auto; margin-top: 1rem; }
table { width: 100%; border-collapse: collapse; }
th, td { padding: 0.8rem; text-align: right; border-bottom: 1px solid var(--border-color); }
th { background-color: var(--bg-color); position: sticky; top: 0; }
tbody tr:nth-child(even) { background-color: var(--bg-color); }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes slideIn { from { transform: translateY(-50px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }


/* --- RESPONSIVE & MOBILE DESIGN --- */
.hamburger { display: none; position: fixed; top: 15px; left: 15px; z-index: 101; background: var(--surface-color); border: 1px solid var(--border-color); border-radius: 8px; width: 44px; height: 44px; flex-direction: column; justify-content: space-around; padding: 8px; cursor: pointer; }
.hamburger span { width: 100%; height: 3px; background-color: var(--text-color); border-radius: 3px; transition: all 0.3s ease-in-out; }

@media (max-width: 992px) {
    .hamburger { display: flex; }
    .sidebar { transform: translateX(-100%); }
    .sidebar.open { transform: translateX(0); }
    .main-content { margin-left: 0; }
    .calculator-container { grid-template-columns: 1fr; }
    .results-summary { grid-template-columns: 1fr; }
    header { flex-direction: column; align-items: flex-start; gap: 1rem; }
    .header-actions { width: 100%; justify-content: space-between; }
    .comparison-calculators { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .main-content { padding: 1.5rem; }
    header h2 { font-size: 1.8rem; }
    .results-summary { grid-template-columns: 1fr; }
    .comparison-results th, .comparison-results td { padding: 0.5rem; font-size: 0.9rem; }
    .comparison-results td:not(:first-child) { font-size: 1rem; }

}

/* --- PRINT & PDF STYLES --- */
.pdf-button { background: var(--success-color); border: none; color: #fff; font-weight: 500; }
.pdf-button:hover { background-color: #218838; }
@media print { body > *:not(.printable-area) { display: none; } .printable-area { display: block; } }