/* ==========================================
   CSS Design Tokens & Theme Variables
   ========================================== */
:root {
    /* Light Mode Palette */
    --bg-primary: #F8FAFC;
    --bg-secondary: #FFFFFF;
    --bg-tertiary: #F1F5F9;
    --border-color: rgba(15, 23, 42, 0.08);
    --border-hover: rgba(220, 38, 38, 0.2);
    --text-primary: #0F172A;
    --text-secondary: #475569;
    --text-muted: #64748B;
    
    --card-shadow: 0 10px 30px -10px rgba(15, 23, 42, 0.06), 0 1px 3px rgba(15, 23, 42, 0.02);
    --card-shadow-hover: 0 20px 45px -15px rgba(220, 38, 38, 0.12), 0 0 0 1px rgba(220, 38, 38, 0.15);
    
    /* Accents */
    --accent: #DC2626; /* Global red */
    --accent-fin: #1D4ED8; /* Financing blue */
    --accent-fin-rgb: 29, 78, 216;
    --accent-con: #DC2626; /* Consortium red */
    --accent-con-rgb: 220, 38, 38;
    
    --font-headings: 'Outfit', sans-serif;
    --font-body: 'Plus Jakarta Sans', sans-serif;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html.dark {
    /* Dark Mode Palette */
    --bg-primary: #080D1A;
    --bg-secondary: #0F172A;
    --bg-tertiary: #1E293B;
    --border-color: rgba(255, 255, 255, 0.06);
    --border-hover: rgba(220, 38, 38, 0.4);
    --text-primary: #F8FAFC;
    --text-secondary: #94A3B8;
    --text-muted: #64748B;
    
    --card-shadow: 0 10px 35px -12px rgba(0, 0, 0, 0.5), 0 1px 3px rgba(0, 0, 0, 0.3);
    --card-shadow-hover: 0 22px 50px -18px rgba(220, 38, 38, 0.22), 0 0 0 1px rgba(220, 38, 38, 0.35);
}

/* ==========================================
   Base resets and styling
   ========================================== */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    height: 100%;
}

body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-family: var(--font-body);
    line-height: 1.6;
    min-height: 100%;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
    transition: background-color 0.4s ease, color 0.4s ease;
}

h1, h2, h3, h4 {
    font-family: var(--font-headings);
    color: var(--text-primary);
    font-weight: 700;
}

a {
    transition: var(--transition);
}

/* Focus states */
a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible {
    outline: 3px solid var(--accent);
    outline-offset: 2px;
}

/* ==========================================
   Header Navbar Layout
   ========================================== */
header {
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition);
}

html.dark header {
    background-color: rgba(15, 23, 42, 0.75);
}

html:not(.dark) header {
    background-color: rgba(255, 255, 255, 0.75);
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0.85rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.back-link {
    display: flex;
    align-items: center;
    gap: 0.35rem;
    text-decoration: none;
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 600;
    padding: 0.4rem 0.85rem;
    border-radius: 8px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
}

.back-link:hover {
    color: var(--accent);
    background: var(--border-color);
    transform: translateX(-2px);
}

.logo-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    color: var(--text-primary);
    font-family: var(--font-headings);
    font-weight: 800;
    font-size: 1.25rem;
    letter-spacing: -0.025em;
}

.logo-icon {
    width: 32px;
    height: 32px;
    background: linear-gradient(135deg, var(--accent) 0%, var(--accent-light) 100%);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #FFFFFF;
    font-weight: 800;
    font-size: 1.1rem;
    box-shadow: 0 4px 10px rgba(220, 38, 38, 0.25);
}

.logo-text-accent {
    color: var(--accent);
}

/* Theme Switcher */
.theme-toggle-btn {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 9999px;
    width: 42px;
    height: 42px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--text-primary);
    position: relative;
    overflow: hidden;
    transition: var(--transition);
}

.theme-toggle-btn:hover {
    background: var(--border-color);
    transform: scale(1.05);
}

.theme-toggle-btn svg {
    width: 18px;
    height: 18px;
    position: absolute;
    transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.3s ease;
}

.sun-icon {
    opacity: 0;
    transform: translateY(30px) rotate(180deg);
}

.moon-icon {
    opacity: 1;
    transform: translateY(0) rotate(0deg);
}

html.dark .sun-icon {
    opacity: 1;
    transform: translateY(0) rotate(0deg);
}

html.dark .moon-icon {
    opacity: 0;
    transform: translateY(-30px) rotate(-180deg);
}

/* ==========================================
   Anchor Navigation Bar
   ========================================== */
.calculator-nav {
    position: sticky;
    top: 60px;
    z-index: 90;
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    gap: 1.5rem;
}

.nav-anchor {
    text-decoration: none;
    color: var(--text-muted);
    font-size: 0.95rem;
    font-family: var(--font-headings);
    font-weight: 600;
    padding: 1rem 0.25rem;
    position: relative;
    border-bottom: 2px solid transparent;
}

.nav-anchor:hover {
    color: var(--accent);
}

.nav-anchor.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
}

/* ==========================================
   Calculator Hero Header
   ========================================== */
.calculator-hero {
    background: linear-gradient(135deg, #090E1A 0%, #152238 100%);
    padding: 3.5rem 1.5rem;
    text-align: center;
    color: #FFFFFF;
    position: relative;
    overflow: hidden;
}

.calculator-hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 80% 20%, rgba(220, 38, 38, 0.12) 0%, transparent 40%),
        radial-gradient(circle at 20% 80%, rgba(29, 78, 216, 0.2) 0%, transparent 50%);
    pointer-events: none;
}

.hero-pattern {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-size: 30px 30px;
    background-image: 
        linear-gradient(to right, rgba(255, 255, 255, 0.01) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(255, 255, 255, 0.01) 1px, transparent 1px);
    mask-image: radial-gradient(circle, black, transparent 80%);
    -webkit-mask-image: radial-gradient(circle, black, transparent 80%);
    pointer-events: none;
}

.hero-content {
    max-width: 750px;
    margin: 0 auto;
    position: relative;
    z-index: 5;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 2.75rem);
    font-weight: 800;
    margin-bottom: 0.75rem;
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-size: clamp(0.95rem, 2vw, 1.1rem);
    color: #94A3B8;
    line-height: 1.5;
}

/* ==========================================
   Main Calculator Grid Layout
   ========================================== */
.main-calculator-layout {
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.calc-grid-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    margin-top: -2.5rem;
    position: relative;
    z-index: 10;
    margin-bottom: 3rem;
}

@media (min-width: 992px) {
    .calc-grid-container {
        grid-template-columns: 1.1fr 0.9fr;
    }
}

.calc-panel {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: var(--card-shadow);
    transition: var(--transition);
}

.panel-title {
    font-size: 1.35rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border-color);
    letter-spacing: -0.02em;
}

/* ==========================================
   Forms & Custom Inputs
   ========================================== */
.input-group {
    margin-bottom: 1.25rem;
}

.input-group label {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.input-wrapper-prefix, .input-wrapper-suffix {
    display: flex;
    align-items: center;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    transition: var(--transition);
    overflow: hidden;
}

.input-wrapper-prefix:focus-within, .input-wrapper-suffix:focus-within {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(220, 38, 38, 0.12);
    background: var(--bg-secondary);
}

.input-prefix, .input-suffix {
    padding: 0 1rem;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-muted);
    user-select: none;
}

.input-wrapper-prefix input, .input-wrapper-suffix input {
    width: 100%;
    border: none;
    background: transparent;
    padding: 0.8rem 0.5rem;
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-primary);
    outline: none;
    font-family: var(--font-body);
}

.input-wrapper-prefix input {
    padding-left: 0.25rem;
}

.input-wrapper-suffix input {
    padding-right: 0.25rem;
    text-align: right;
}

.downpayment-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.select-urgency {
    width: 100%;
    border: 1px solid var(--border-color);
    background: var(--bg-tertiary);
    color: var(--text-primary);
    padding: 0.8rem 1rem;
    font-family: var(--font-body);
    font-weight: 600;
    font-size: 0.92rem;
    border-radius: 10px;
    outline: none;
    cursor: pointer;
    transition: var(--transition);
}

.select-urgency:focus {
    border-color: var(--accent);
    background: var(--bg-secondary);
    box-shadow: 0 0 0 3px rgba(220, 38, 38, 0.12);
}

.input-help-text {
    font-size: 0.78rem;
    color: var(--text-muted);
    margin-top: 0.35rem;
    line-height: 1.3;
}

.input-readonly {
    background-color: var(--bg-tertiary) !important;
    cursor: not-allowed;
    color: var(--text-muted) !important;
}

/* ==========================================
   Split Form Variables Container
   ========================================== */
.split-variables-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
    margin-top: 2rem;
    border-top: 1px dashed var(--border-color);
    padding-top: 2rem;
}

@media (min-width: 576px) {
    .split-variables-container {
        grid-template-columns: 1fr 1fr;
    }
}

.param-card {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 1.5rem;
    transition: var(--transition);
}

.param-card-title {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 1.25rem;
    display: flex;
    align-items: center;
    gap: 0.35rem;
}

/* Color indicator highlights on variables cards */
.param-financing {
    border-top: 4px solid var(--accent-fin);
}

.param-financing:focus-within {
    border-color: var(--accent-fin);
    box-shadow: 0 10px 20px -10px rgba(var(--accent-fin-rgb), 0.1);
}

.param-consorcio {
    border-top: 4px solid var(--accent-con);
}

.param-consorcio:focus-within {
    border-color: var(--accent-con);
    box-shadow: 0 10px 20px -10px rgba(var(--accent-con-rgb), 0.1);
}

/* ==========================================
   Results Column Layout
   ========================================== */
.results-panel {
    border-top: 4px solid var(--accent);
}

/* Recommendation Banner Box styles */
.recommendation-alert-box {
    border-radius: 16px;
    padding: 1.5rem;
    margin-bottom: 2rem;
    font-weight: 500;
    line-height: 1.5;
    font-size: 0.95rem;
    transition: var(--transition);
    border: 1px solid transparent;
}

.recommendation-alert-box.rec-financing {
    background: linear-gradient(135deg, rgba(29, 78, 216, 0.08) 0%, rgba(29, 78, 216, 0.01) 100%);
    border-color: rgba(29, 78, 216, 0.2);
    color: var(--text-primary);
}

.recommendation-alert-box.rec-consorcio {
    background: linear-gradient(135deg, rgba(220, 38, 38, 0.08) 0%, rgba(220, 38, 38, 0.01) 100%);
    border-color: rgba(220, 38, 38, 0.2);
    color: var(--text-primary);
}

/* Side-by-Side Comparison Table */
.comparison-table-container {
    width: 100%;
    overflow-x: auto;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    margin-bottom: 2.5rem;
}

.comparison-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.92rem;
    text-align: left;
}

.comparison-table th, .comparison-table td {
    padding: 1rem 1.15rem;
    border-bottom: 1px solid var(--border-color);
}

.comparison-table th[scope="row"] {
    font-weight: 600;
    color: var(--text-secondary);
    background: var(--bg-tertiary);
    width: 38%;
}

.comparison-table thead th {
    background: var(--bg-tertiary);
    font-weight: 700;
    font-family: var(--font-headings);
    color: var(--text-primary);
}

/* Align comparisons column headings style */
.header-financing {
    color: var(--accent-fin) !important;
    border-bottom: 2px solid var(--accent-fin);
}

.header-consorcio {
    color: var(--accent-con) !important;
    border-bottom: 2px solid var(--accent-con);
}

.comparison-table tr:last-child th, .comparison-table tr:last-child td {
    border-bottom: none;
}

.text-fin-accent {
    color: var(--accent-fin);
    font-weight: 700;
}

.text-con-accent {
    color: var(--accent-con);
    font-weight: 700;
}

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

/* ==========================================
   Line Chart Styles
   ========================================== */
.chart-layout-box {
    border-top: 1px dashed var(--border-color);
    padding-top: 2rem;
}

.chart-title {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 0.35rem;
}

.chart-subtitle {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}

.chart-canvas-wrapper {
    width: 100%;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1rem;
    display: flex;
    justify-content: center;
}

/* SVG configurations */
.line-chart-svg {
    width: 100%;
    height: auto;
    max-height: 240px;
    overflow: visible;
}

.chart-grid-lines line {
    stroke: var(--border-color);
    stroke-width: 1;
    stroke-dasharray: 4 4;
}

.chart-axes line, .chart-axes path {
    stroke: var(--text-muted);
    stroke-width: 1.5;
}

.chart-axes text {
    fill: var(--text-muted);
    font-size: 8px;
    font-family: var(--font-body);
    user-select: none;
}

.chart-line {
    fill: none;
    stroke-width: 3;
    stroke-linecap: round;
    stroke-linejoin: round;
    transition: stroke-dasharray 0.5s ease;
}

/* Chart Line colors */
.line-financing {
    stroke: var(--accent-fin);
}

.line-consorcio {
    stroke: var(--accent-con);
}

.chart-dot {
    fill: var(--bg-secondary);
    stroke-width: 2;
    transition: r 0.2s ease;
    cursor: pointer;
}

.chart-dot:hover {
    r: 6;
}

.dot-fin { stroke: var(--accent-fin); }
.dot-con { stroke: var(--accent-con); }

/* Legend for SVG chart */
.chart-legend {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-top: 1.25rem;
    font-size: 0.8rem;
}

.legend-dot-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
}

.legend-color-line {
    width: 20px;
    height: 4px;
    border-radius: 2px;
    display: inline-block;
}

.line-color-fin { background-color: var(--accent-fin); }
.line-color-con { background-color: var(--accent-con); }

/* ==========================================
   SEO Content & FAQ Sections
   ========================================== */
.seo-resources-section {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 2.5rem;
    box-shadow: var(--card-shadow);
    margin-bottom: 5rem;
}

.seo-main-title {
    font-size: 1.75rem;
    margin-bottom: 2rem;
    position: relative;
    display: inline-block;
    letter-spacing: -0.02em;
}

.seo-main-title::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 40px;
    height: 3px;
    background-color: var(--accent);
    border-radius: 9999px;
}

.seo-article {
    display: flex;
    flex-direction: column;
    gap: 1.75rem;
}

.seo-subtitle {
    font-size: 1.25rem;
    margin-top: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.seo-content-para p {
    font-size: 0.98rem;
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.65;
}

.seo-content-para p:last-child {
    margin-bottom: 0;
}

/* ==========================================
   Footer Layout
   ========================================== */
footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 3rem 1.5rem;
    margin-top: auto;
    transition: var(--transition);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    text-align: center;
}

.footer-brand {
    font-family: var(--font-headings);
    font-weight: 800;
    font-size: 1.1rem;
    color: var(--text-primary);
}

.footer-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.footer-link {
    text-decoration: none;
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 500;
}

.footer-link:hover {
    color: var(--accent);
}

.footer-copyright {
    font-size: 0.85rem;
    color: var(--text-muted);
}