:root {
    --bg-base: #F7F7F5;
    --bg-surface: #FFFFFF;
    --bg-dark: #111820;
    --bg-darker: #0A0F14;
    
    --text-main: #2C3539;
    --text-dark: #111820;
    --text-light: #F7F7F5;
    --text-muted: #6B7280;
    
    --accent: #B89C65;
    --accent-hover: #9A8151;
    
    --border-light: #E2E2DC;
    --border-dark: #2C3539;
    
    --font-heading: 'Zen Old Mincho', serif;
    --font-body: 'Inter', system-ui, -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 2rem;
    --space-lg: 4rem;
    --space-xl: 8rem;
    
    --radius: 0px; /* Sharp corners for premium corporate feel */
    --transition: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

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

img, picture, video, canvas, svg {
    display: block;
    max-width: 100%;
    height: auto;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-body);
    background-color: var(--bg-base);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    color: var(--text-dark);
    line-height: 1.2;
    font-weight: 700;
}

h1 { font-size: clamp(2.5rem, 5vw, 4.5rem); letter-spacing: -0.02em; }
h2 { font-size: clamp(2rem, 4vw, 3rem); letter-spacing: -0.01em; }
h3 { font-size: clamp(1.5rem, 2.5vw, 2rem); }
h4 { font-size: 1.25rem; }

p {
    margin-bottom: var(--space-sm);
    font-size: 1.125rem;
    max-width: 70ch;
}

.text-sm { font-size: 0.875rem; }
.text-lg { font-size: 1.25rem; }
.text-center { text-align: center; }
.text-accent { color: var(--accent); }
.mono { font-family: var(--font-mono); font-size: 0.9em; letter-spacing: 0.05em; text-transform: uppercase;}

/* Layout */
.container {
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: var(--space-xl) 0;
    position: relative;
}

.section-sm {
    padding: var(--space-lg) 0;
}

.grid {
    display: grid;
    gap: var(--space-lg);
}

.grid-2 { grid-template-columns: 1fr; }
.grid-3 { grid-template-columns: 1fr; }
.grid-4 { grid-template-columns: 1fr; }

@media (min-width: 768px) {
    .grid-2 { grid-template-columns: repeat(2, 1fr); }
    .grid-4 { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 1024px) {
    .grid-3 { grid-template-columns: repeat(3, 1fr); }
    .grid-4 { grid-template-columns: repeat(4, 1fr); }
}

/* Header & Navigation */
.site-header {
    background-color: rgba(247, 247, 245, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-light);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    transition: transform var(--transition);
}

.site-header.scroll-down {
    transform: translateY(-100%);
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.logo span {
    font-weight: 400;
    color: var(--accent);
}

.main-nav {
    display: none;
}

.main-nav ul {
    list-style: none;
    display: flex;
    gap: 2rem;
}

.main-nav a {
    text-decoration: none;
    color: var(--text-main);
    font-size: 0.875rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    transition: color var(--transition);
    position: relative;
}

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 1px;
    background-color: var(--accent);
    transition: width var(--transition);
}

.main-nav a:hover::after, .main-nav a.active::after {
    width: 100%;
}

.mobile-toggle {
    display: block;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--text-dark);
    margin-bottom: 5px;
    transition: var(--transition);
}

.mobile-toggle span:last-child { margin-bottom: 0; }

@media (min-width: 1024px) {
    .main-nav { display: block; }
    .mobile-toggle { display: none; }
}

/* Mobile Menu */
.mobile-menu {
    position: fixed;
    top: 80px;
    left: 0;
    width: 100%;
    height: calc(100vh - 80px);
    background-color: var(--bg-base);
    padding: var(--space-md);
    transform: translateX(100%);
    transition: transform var(--transition);
    z-index: 999;
    overflow-y: auto;
}

.mobile-menu.active {
    transform: translateX(0);
}

.mobile-menu ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.mobile-menu a {
    text-decoration: none;
    font-family: var(--font-heading);
    font-size: 2rem;
    color: var(--text-dark);
    display: block;
    border-bottom: 1px solid var(--border-light);
    padding-bottom: 1rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 1rem 2rem;
    font-size: 0.875rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    text-decoration: none;
    border: 1px solid var(--border-dark);
    background-color: transparent;
    color: var(--text-dark);
    transition: all var(--transition);
    cursor: pointer;
}

.btn-primary {
    background-color: var(--bg-dark);
    color: var(--text-light);
    border-color: var(--bg-dark);
}

.btn-primary:hover {
    background-color: var(--accent);
    border-color: var(--accent);
}

.btn-outline:hover {
    background-color: var(--bg-dark);
    color: var(--text-light);
}

/* Hero Section */
.hero {
    min-height: 90vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
    border-bottom: 1px solid var(--border-light);
    position: relative;
    overflow: hidden;
}

.hero::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 50%;
    height: 100%;
    background: radial-gradient(circle at center, rgba(184, 156, 101, 0.05) 0%, transparent 70%);
    z-index: -1;
}

.hero-content {
    max-width: 800px;
}

.hero-subtitle {
    font-family: var(--font-mono);
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--space-sm);
    display: block;
}

.hero h1 {
    margin-bottom: var(--space-md);
}

/* Structural Components */
.structural-line {
    width: 1px;
    height: 100%;
    background-color: var(--border-light);
    position: absolute;
    top: 0;
    z-index: -1;
}

.line-1 { left: 25%; }
.line-2 { left: 50%; }
.line-3 { left: 75%; }

@media (max-width: 1024px) {
    .structural-line { display: none; }
}

/* Cards & Modules (Boutique Style) */
.module {
    border: 1px solid var(--border-light);
    background-color: var(--bg-surface);
    padding: var(--space-md);
    transition: transform var(--transition), border-color var(--transition);
    position: relative;
}

.module::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--transition);
}

.module:hover {
    transform: translateY(-5px);
    border-color: var(--accent);
}

.module:hover::before {
    transform: scaleX(1);
}

.module-number {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--accent);
    margin-bottom: var(--space-sm);
}

/* Framework Tables */
.framework-table {
    width: 100%;
    border-collapse: collapse;
    margin: var(--space-md) 0;
}

.framework-table th, .framework-table td {
    padding: 1.5rem;
    border: 1px solid var(--border-light);
    text-align: left;
}

.framework-table th {
    font-family: var(--font-heading);
    background-color: var(--bg-surface);
    color: var(--text-dark);
}

@media (max-width: 768px) {
    .framework-table, .framework-table tbody, .framework-table tr, .framework-table th, .framework-table td {
        display: block;
        width: 100%;
    }
    .framework-table th {
        display: none;
    }
    .framework-table tr {
        margin-bottom: 1rem;
        border: 1px solid var(--border-light);
    }
    .framework-table td {
        border: none;
        border-bottom: 1px solid var(--border-light);
        padding: 1rem;
    }
    .framework-table td:last-child {
        border-bottom: none;
    }
}

/* Dark Section */
.bg-dark {
    background-color: var(--bg-dark);
    color: var(--text-light);
}

.bg-dark h2, .bg-dark h3, .bg-dark .logo {
    color: var(--bg-base);
}

.bg-dark .module {
    background-color: var(--bg-darker);
    border-color: var(--border-dark);
}

.bg-dark .module:hover {
    border-color: var(--accent);
}

.bg-dark p {
    color: #A0AAB2;
}

/* Footer */
.site-footer {
    background-color: var(--bg-darker);
    color: var(--text-light);
    padding: var(--space-xl) 0 var(--space-md);
    border-top: 1px solid var(--border-dark);
}

.footer-top {
    margin-bottom: var(--space-xl);
}

.footer-top h2 {
    color: var(--bg-base);
}

.footer-nav h4 {
    color: var(--bg-base);
    font-family: var(--font-mono);
    text-transform: uppercase;
    font-size: 0.875rem;
    letter-spacing: 0.1em;
    margin-bottom: 1.5rem;
}

.footer-nav ul {
    list-style: none;
}

.footer-nav li {
    margin-bottom: 0.75rem;
}

.footer-nav a {
    color: #A0AAB2;
    text-decoration: none;
    transition: color var(--transition);
}

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

.footer-bottom {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    border-top: 1px solid var(--border-dark);
    padding-top: var(--space-md);
    font-size: 0.875rem;
    color: #A0AAB2;
}

@media (min-width: 768px) {
    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
    }
}

/* Animations */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Forms */
input, textarea, select {
    font-family: var(--font-body);
    font-size: 1rem;
    padding: 0.75rem;
    border: 1px solid var(--border-light);
    background-color: transparent;
    color: inherit;
    width: 100%;
    outline: none;
    transition: border-color var(--transition);
}

input:focus, textarea:focus, select:focus {
    border-color: var(--accent);
}

.bg-dark input, .bg-dark textarea, .bg-dark select {
    border-color: var(--border-dark);
    color: var(--text-light);
}

.bg-dark input:focus, .bg-dark textarea:focus, .bg-dark select:focus {
    border-color: var(--accent);
}