/* ==========================================================================
   KDC ARCHITECTS — PRISTINE LIGHT ARCHITECTURAL STUDIO EXPERIENCE (GREEN THEME)
   High-End Emerald & Architectural Forest Green Palette with Off-White Canvas
   ========================================================================== */

:root {
    --bg-main: #FAFAFA;
    --bg-sec: #FFFFFF;
    --bg-card: #FFFFFF;
    --bg-subtle: #F1F5F9;
    
    --gold: #059669; /* Emerald Green Primary */
    --gold-dark: #047857; /* Deep Architectural Forest Green */
    --gold-bright: #10B981; /* Vibrant Mint/Emerald Accent */
    --gold-glow: rgba(5, 150, 105, 0.15);

    --steel: #475569;
    --concrete: #64748B;
    --blueprint-blue: #1E40AF;
    --charcoal: #0F172A;
    --muted: #64748B;

    --border-line: #E2E8F0;
    --border-dark: #CBD5E1;
    --border-accent: rgba(5, 150, 105, 0.3);

    --font-serif: 'Cormorant Garamond', Georgia, serif;
    --font-sans: 'Manrope', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;

    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 12px 35px rgba(0, 0, 0, 0.08);
}

/* Reset & Core Setup */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    background-color: var(--bg-main);
    color: var(--charcoal);
    font-family: var(--font-sans);
}

body.light-theme {
    overflow-x: hidden;
    line-height: 1.6;
    background-color: var(--bg-main);
    color: var(--charcoal);
    cursor: default;
}

/* Custom Architectural Cursor */
.custom-cursor {
    position: fixed;
    top: 0;
    left: 0;
    width: 28px;
    height: 28px;
    pointer-events: none;
    z-index: 10000;
    transform: translate(-50%, -50%);
    transition: transform 0.1s ease-out, opacity 0.3s ease;
}

.cursor-dot {
    width: 6px;
    height: 6px;
    background: var(--gold-dark);
    border-radius: 50%;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.cursor-crosshair {
    width: 22px;
    height: 22px;
    border: 1px solid rgba(5, 150, 105, 0.5);
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    border-radius: 50%;
}

.cursor-label {
    position: absolute;
    top: 28px;
    left: 50%;
    transform: translateX(-50%);
    font-family: var(--font-mono);
    font-size: 0.6rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    color: var(--gold-dark);
    white-space: nowrap;
    opacity: 0;
    transition: opacity 0.2s ease;
}

.custom-cursor.hovering .cursor-crosshair {
    transform: translate(-50%, -50%) scale(1.5);
    border-color: var(--gold-dark);
}

.custom-cursor.hovering .cursor-label {
    opacity: 1;
}

/* Loader Screen */
.loader-overlay {
    position: fixed;
    inset: 0;
    background: #FFFFFF;
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity 0.6s ease, visibility 0.6s ease;
}

.loader-overlay.hidden {
    opacity: 0;
    visibility: hidden;
}

.loader-content {
    text-align: center;
    max-width: 550px;
    padding: 0 24px;
}

.loader-coord {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--gold-dark);
    font-weight: 700;
    letter-spacing: 0.15em;
    margin-bottom: 24px;
}

.loader-brand {
    font-family: var(--font-sans);
    font-size: 2.2rem;
    font-weight: 800;
    letter-spacing: 0.25em;
    color: var(--charcoal);
    margin-bottom: 12px;
}

.loader-sub {
    font-family: var(--font-serif);
    font-style: italic;
    font-size: 1.2rem;
    color: var(--steel);
    margin-bottom: 32px;
}

.loader-progress-bar {
    width: 100%;
    height: 3px;
    background: #E2E8F0;
    overflow: hidden;
    border-radius: 2px;
}

.loader-progress-fill {
    height: 100%;
    width: 0%;
    background: var(--gold-dark);
    transition: width 0.1s linear;
}

/* Background Grid Overlay */
.bg-grid-overlay {
    position: fixed;
    inset: 0;
    background-image: 
        linear-gradient(to right, rgba(15, 23, 42, 0.03) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(15, 23, 42, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
    pointer-events: none;
    z-index: 0;
}

/* Container */
.container {
    max-width: 1360px;
    margin: 0 auto;
    padding: 0 32px;
    position: relative;
    z-index: 1;
}

/* Typography Utilities */
.serif-italic {
    font-family: var(--font-serif);
    font-style: italic;
    font-weight: 400;
}

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

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 85px;
    z-index: 500;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border-line);
    transition: all 0.3s ease;
    box-shadow: var(--shadow-sm);
}

.nav-container {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 40px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.brand-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}

.logo-svg-wrapper {
    display: flex;
    align-items: center;
    justify-content: center;
}

.brand-name {
    font-family: var(--font-sans);
    font-weight: 800;
    font-size: 1.15rem;
    letter-spacing: 0.1em;
    color: var(--charcoal);
}

.brand-tag {
    display: block;
    font-size: 0.58rem;
    font-family: var(--font-mono);
    letter-spacing: 0.15em;
    color: var(--steel);
    font-weight: 700;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 20px;
}

.nav-item {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    color: var(--steel);
    text-decoration: none;
    transition: color 0.2s ease;
}

.nav-item:hover { color: var(--gold-dark); }

.nav-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

.sound-btn {
    background: #FFFFFF;
    border: 1px solid var(--border-line);
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    color: var(--steel);
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    font-family: var(--font-mono);
    font-size: 0.65rem;
    font-weight: 700;
    transition: all 0.2s ease;
    box-shadow: var(--shadow-sm);
}

.sound-btn:hover {
    border-color: var(--gold);
    color: var(--gold-dark);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 12px 24px;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.25s ease;
    border-radius: var(--radius-sm);
}

.btn-gold {
    border: 1px solid var(--gold-dark);
    color: var(--gold-dark);
    background: rgba(5, 150, 105, 0.06);
}

.btn-gold:hover {
    background: var(--gold-dark);
    color: #FFFFFF;
    box-shadow: var(--shadow-md);
}

.btn-gold-fill {
    background: var(--charcoal);
    color: #FFFFFF;
}

.btn-gold-fill:hover {
    background: var(--gold-dark);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.btn-outline {
    border: 1px solid var(--border-dark);
    color: var(--charcoal);
    background: #FFFFFF;
}

.btn-outline:hover {
    border-color: var(--gold-dark);
    color: var(--gold-dark);
}

.btn-full { width: 100%; }

/* Tech Tags */
.tech-tag {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-family: var(--font-mono);
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    color: var(--gold-dark);
    margin-bottom: 20px;
}

.tag-badge {
    background: rgba(5, 150, 105, 0.1);
    padding: 2px 8px;
    border-radius: 2px;
    border: 1px solid rgba(5, 150, 105, 0.3);
}

/* ==========================================================================
   FULL-WIDTH HERO & PINNED 3D CANVAS SECTION (HD CRISP OVERLAY)
   ========================================================================== */
.digital-twin-section {
    position: relative;
    height: 400vh;
    width: 100%;
}

.hero-bg-canvas-container {
    position: sticky;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    overflow: hidden;
    z-index: 0;
    background: #0F172A;
}

canvas#building-canvas {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: cover;
}

.hero-bg-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, 
        rgba(250, 250, 250, 0.85) 0%, 
        rgba(250, 250, 250, 0.5) 40%, 
        rgba(250, 250, 250, 0.05) 100%);
    pointer-events: none;
    z-index: 1;
}

.digital-twin-sticky-container {
    position: sticky;
    top: 0;
    height: 100vh;
    width: 100%;
    max-width: 1440px;
    margin: -100vh auto 0 auto;
    padding: 110px 40px 40px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 2;
    pointer-events: none;
}

.digital-twin-sticky-container * {
    pointer-events: auto;
}

.hero-left-card {
    max-width: 600px;
}

.hero-headline {
    font-family: var(--font-sans);
    font-size: 4rem;
    font-weight: 800;
    line-height: 1.08;
    letter-spacing: -0.02em;
    margin-bottom: 20px;
    color: var(--charcoal);
}

.hero-subline {
    font-size: 1.1rem;
    color: var(--steel);
    margin-bottom: 32px;
    line-height: 1.6;
}

.hero-cta-group {
    display: flex;
    gap: 16px;
}

/* Stage Nav Bar */
.hero-right-hud {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
}

.stage-nav-vertical {
    display: flex;
    flex-direction: column;
    gap: 20px;
    border-right: 2px solid var(--border-line);
    padding-right: 20px;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    padding: 20px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-line);
    box-shadow: var(--shadow-md);
}

.stage-step {
    display: flex;
    align-items: center;
    gap: 12px;
    cursor: pointer;
    opacity: 0.5;
    transition: all 0.3s ease;
}

.stage-step.active {
    opacity: 1;
}

.step-num {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--gold-dark);
}

.step-lbl {
    font-family: var(--font-sans);
    font-size: 0.8rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    color: var(--charcoal);
}

/* CAD Overlay Annotations */
.canvas-cad-overlay {
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.cad-label-box {
    position: absolute;
    display: flex;
    align-items: center;
    gap: 10px;
    opacity: 0;
    transition: opacity 0.4s ease;
}

.cad-label-box.visible { opacity: 1; }

.cad-dot {
    width: 8px;
    height: 8px;
    background: var(--gold-bright);
    border-radius: 50%;
    box-shadow: 0 0 10px var(--gold-bright);
}

.cad-text {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(8px);
    border: 1px solid var(--border-dark);
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    box-shadow: var(--shadow-sm);
}

.cad-text strong { display: block; font-size: 0.75rem; color: var(--charcoal); }
.cad-text span { font-size: 0.65rem; color: var(--steel); font-weight: 600; }

/* HUD Bar */
.transformation-hud {
    position: absolute;
    bottom: 24px;
    left: 40px;
    right: 40px;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border-line);
    border-radius: var(--radius-md);
    padding: 14px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow-md);
}

.hud-stage-title {
    font-family: var(--font-sans);
    font-size: 0.9rem;
    font-weight: 800;
    letter-spacing: 0.05em;
    color: var(--charcoal);
}

.hud-sub { font-size: 0.78rem; color: var(--steel); }

.hud-right { display: flex; gap: 24px; }
.hud-stat { text-align: right; }
.hud-stat-lbl { display: block; font-family: var(--font-mono); font-size: 0.6rem; font-weight: 700; color: var(--steel); }
.hud-stat-val { font-family: var(--font-mono); font-size: 1.1rem; font-weight: 700; color: var(--charcoal); }

/* INTELLIGENCE SECTION */
.intelligence-section { padding: 100px 0; }

.editorial-quote {
    font-family: var(--font-sans);
    font-size: 3rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 50px;
    color: var(--charcoal);
}

.systems-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.system-card {
    background: #FFFFFF;
    border: 1px solid var(--border-line);
    border-radius: var(--radius-md);
    padding: 28px 24px;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.system-card:hover {
    border-color: var(--gold-dark);
    transform: translateY(-6px);
    box-shadow: var(--shadow-md);
}

.sys-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-line);
}

.sys-code {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.1em;
}

.sys-icon {
    width: 20px;
    height: 20px;
    color: var(--steel);
    transition: color 0.3s ease;
}

.system-card:hover .sys-icon {
    color: var(--gold-dark);
}

.system-title { font-family: var(--font-sans); font-size: 1.2rem; font-weight: 800; margin-bottom: 10px; color: var(--charcoal); }
.system-desc { font-size: 0.84rem; color: var(--steel); line-height: 1.55; margin-bottom: 16px; }

.system-diagram-box {
    width: 100%;
    background: #FAFAFA;
    border: 1px solid var(--border-line);
    border-radius: var(--radius-sm);
    padding: 10px;
    transition: all 0.3s ease;
}

.system-card:hover .system-diagram-box {
    background: #FFFFFF;
    border-color: rgba(5, 150, 105, 0.4);
    box-shadow: var(--shadow-sm);
}

.blueprint-svg {
    width: 100%;
    height: auto;
    display: block;
}

/* MATERIAL INTELLIGENCE SECTION */
.materials-section { padding: 100px 0; background: #FFFFFF; border-top: 1px solid var(--border-line); border-bottom: 1px solid var(--border-line); }
.section-title-editorial { font-family: var(--font-sans); font-size: 2.8rem; font-weight: 800; margin-bottom: 12px; color: var(--charcoal); }
.section-sub { font-size: 1.05rem; color: var(--steel); max-width: 650px; margin-bottom: 50px; }

.materials-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.material-tile {
    position: relative;
    background: #FFFFFF;
    border: 1px solid var(--border-line);
    border-radius: var(--radius-md);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: var(--shadow-sm);
}

.material-tile:hover {
    border-color: var(--gold-dark);
    transform: translateY(-6px);
    box-shadow: var(--shadow-md);
}

.mat-img-wrapper {
    position: relative;
    width: 100%;
    height: 180px;
    overflow: hidden;
    background: #F1F5F9;
}

.mat-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.material-tile:hover .mat-img {
    transform: scale(1.08);
}

.mat-badge {
    position: absolute;
    top: 14px;
    left: 14px;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(8px);
    border: 1px solid var(--border-dark);
    padding: 4px 10px;
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.7rem;
    font-weight: 700;
    color: var(--gold-dark);
    box-shadow: var(--shadow-sm);
}

.mat-content {
    padding: 20px;
    display: flex;
    flex-direction: column;
    flex: 1;
}

.mat-name { font-family: var(--font-sans); font-size: 1.2rem; font-weight: 800; margin-bottom: 12px; color: var(--charcoal); }

.mat-specs { display: flex; flex-direction: column; gap: 6px; font-size: 0.78rem; border-top: 1px solid var(--border-line); padding-top: 12px; margin-top: auto; }
.spec-line { display: flex; justify-content: space-between; color: var(--steel); }
.spec-line strong { color: var(--charcoal); }

/* BIM SYSTEM LAYERS */
.bim-layers-section { padding: 100px 0; }
.bim-wrapper { background: #FFFFFF; border: 1px solid var(--border-line); border-radius: var(--radius-lg); padding: 32px; box-shadow: var(--shadow-sm); }
.bim-controls { display: flex; gap: 12px; margin-bottom: 24px; flex-wrap: wrap; }
.bim-btn {
    background: #FAFAFA;
    border: 1px solid var(--border-line);
    color: var(--steel);
    font-family: var(--font-mono);
    font-size: 0.72rem;
    font-weight: 700;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.2s ease;
}

.bim-btn.active, .bim-btn:hover {
    border-color: var(--gold-dark);
    color: #FFFFFF;
    background: var(--charcoal);
}

.bim-stage { position: relative; width: 100%; aspect-ratio: 16 / 9; max-height: 520px; background: #0F172A; border-radius: var(--radius-md); overflow: hidden; }
canvas#bim-canvas { width: 100%; height: 100%; display: block; }
.bim-info-overlay { position: absolute; bottom: 20px; left: 20px; max-width: 450px; background: rgba(255,255,255,0.95); backdrop-filter: blur(10px); padding: 16px 20px; border-radius: var(--radius-sm); border: 1px solid var(--border-dark); box-shadow: var(--shadow-md); }
.bim-tag { font-family: var(--font-mono); font-size: 0.75rem; font-weight: 700; margin-bottom: 6px; }
.bim-desc { font-size: 0.8rem; color: var(--steel); }

/* PAN INDIA MAP SECTION */
.pan-india-section { padding: 100px 0; background: #F1F5F9; border-top: 1px solid var(--border-line); border-bottom: 1px solid var(--border-line); }
.flex-between { display: flex; justify-content: space-between; }
.align-end { align-items: flex-end; }
.map-stats-strip { display: flex; gap: 32px; }
.m-val { font-family: var(--font-serif); font-size: 2.2rem; font-weight: 700; display: block; color: var(--charcoal); }
.m-lbl { font-family: var(--font-mono); font-size: 0.65rem; font-weight: 700; color: var(--steel); }

.map-wrapper {
    position: relative;
    width: 100%;
    height: 520px;
    margin-top: 40px;
    border: 1px solid var(--border-dark);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.india-map-container {
    width: 100%;
    height: 100%;
    background: #0F172A !important;
}

.leaflet-container { background: #0F172A !important; }
.leaflet-tile { filter: brightness(0.7) invert(0.9) contrast(2) saturate(0.2); }

.map-drawer {
    position: absolute;
    top: 0;
    right: 0;
    width: 420px;
    height: 100%;
    background: #FFFFFF;
    border-left: 1px solid var(--border-line);
    padding: 32px;
    z-index: 1000;
    transform: translateX(100%);
    transition: transform 0.4s ease;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
}

.map-drawer.open { transform: translateX(0); }
.drawer-close { position: absolute; top: 20px; right: 20px; background: none; border: none; color: var(--steel); font-size: 1.8rem; cursor: pointer; }
.drawer-city-tag { font-family: var(--font-mono); font-size: 0.75rem; font-weight: 700; }
.drawer-title { font-family: var(--font-sans); font-size: 1.4rem; font-weight: 800; margin-bottom: 20px; color: var(--charcoal); }
.drawer-img-box { width: 100%; height: 180px; border-radius: var(--radius-sm); overflow: hidden; margin-bottom: 20px; border: 1px solid var(--border-line); }
.drawer-img-box img { width: 100%; height: 100%; object-fit: cover; }
.drawer-specs-grid { display: flex; flex-direction: column; gap: 8px; font-size: 0.8rem; margin-bottom: 20px; }
.d-spec { display: flex; justify-content: space-between; color: var(--steel); border-bottom: 1px solid var(--border-line); padding-bottom: 6px; }
.d-spec strong { color: var(--charcoal); }
.drawer-desc { font-size: 0.85rem; color: var(--steel); margin-bottom: 24px; }

/* CASE STUDIES SECTION */
.case-studies-section { padding: 100px 0; }
.case-studies-list { display: flex; flex-direction: column; gap: 70px; margin-top: 50px; }

.case-study-item { display: flex; flex-direction: column; gap: 20px; border-bottom: 1px solid var(--border-line); padding-bottom: 50px; }
.cs-header { display: flex; gap: 24px; align-items: baseline; }
.cs-num { font-family: var(--font-mono); font-size: 1.5rem; font-weight: 700; color: var(--gold-dark); }
.cs-tag { font-family: var(--font-mono); font-size: 0.72rem; font-weight: 700; color: var(--steel); letter-spacing: 0.1em; display: block; margin-bottom: 4px; }
.cs-title { font-family: var(--font-sans); font-size: 2.2rem; font-weight: 800; color: var(--charcoal); }

.cs-visual { position: relative; width: 100%; height: 480px; border-radius: var(--radius-md); overflow: hidden; border: 1px solid var(--border-line); box-shadow: var(--shadow-md); }
.cs-visual img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.6s ease; }
.case-study-item:hover .cs-visual img { transform: scale(1.03); }
.cs-overlay-tag { position: absolute; bottom: 20px; right: 20px; background: #FFFFFF; border: 1px solid var(--border-dark); padding: 6px 14px; border-radius: var(--radius-sm); font-family: var(--font-mono); font-size: 0.75rem; font-weight: 700; color: var(--gold-dark); box-shadow: var(--shadow-sm); }

.cs-details-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; margin-top: 16px; }
.cs-col h4 { font-family: var(--font-mono); font-size: 0.75rem; font-weight: 700; color: var(--gold-dark); letter-spacing: 0.1em; margin-bottom: 8px; }
.cs-col p { font-size: 0.88rem; color: var(--steel); line-height: 1.6; }

/* PRODUCTION LINE HORIZONTAL CHAIN (INTERACTIVE) */
.production-line-section { padding: 100px 0; background: #FFFFFF; border-top: 1px solid var(--border-line); border-bottom: 1px solid var(--border-line); }
.horizontal-chain { width: 100%; overflow-x: auto; padding: 30px 0; }
.chain-track { display: flex; align-items: center; min-width: 1100px; justify-content: space-between; }

.chain-node {
    background: #FAFAFA;
    border: 1px solid var(--border-line);
    border-radius: var(--radius-md);
    padding: 20px 16px;
    width: 150px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: var(--shadow-sm);
    user-select: none;
}

.chain-node:hover {
    border-color: var(--gold-dark);
    transform: translateY(-4px);
    background: #FFFFFF;
    box-shadow: var(--shadow-md);
}

.chain-node.active {
    border-color: var(--gold-dark);
    background: #FFFFFF;
    box-shadow: var(--shadow-md);
    transform: translateY(-6px) scale(1.04);
}

.chain-node.active .node-num {
    color: var(--gold-dark);
}

.node-icon-box { margin-bottom: 8px; color: var(--steel); display: flex; justify-content: center; transition: color 0.3s ease; }
.chain-node.active .node-icon-box, .chain-node:hover .node-icon-box { color: var(--gold-dark); }
.node-num { font-family: var(--font-mono); font-size: 0.7rem; font-weight: 700; color: var(--steel); display: block; margin-bottom: 4px; }
.chain-node h4 { font-family: var(--font-sans); font-size: 0.85rem; font-weight: 800; margin-bottom: 4px; color: var(--charcoal); }
.chain-node p { font-size: 0.68rem; color: var(--steel); }
.chain-line { flex: 1; height: 2px; background: var(--border-line); margin: 0 6px; }

/* Dynamic Chain Detail Panel */
.chain-detail-panel {
    margin-top: 32px;
    background: #FAFAFA;
    border: 1px solid var(--border-line);
    border-radius: var(--radius-lg);
    padding: 32px 40px;
    box-shadow: var(--shadow-sm);
    transition: all 0.4s ease;
}

.panel-inner {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 40px;
    align-items: center;
}

.panel-code {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    display: block;
    margin-bottom: 8px;
}

.panel-title {
    font-family: var(--font-sans);
    font-size: 1.6rem;
    font-weight: 800;
    color: var(--charcoal);
    margin-bottom: 12px;
}

.panel-desc {
    font-size: 0.92rem;
    color: var(--steel);
    line-height: 1.65;
}

.panel-metrics-grid {
    display: flex;
    flex-direction: column;
    gap: 10px;
    background: #FFFFFF;
    border: 1px solid var(--border-line);
    border-radius: var(--radius-md);
    padding: 20px;
}

.p-metric {
    display: flex;
    justify-content: space-between;
    font-size: 0.82rem;
    color: var(--steel);
    border-bottom: 1px solid var(--border-line);
    padding-bottom: 8px;
}

.p-metric:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.p-metric strong {
    color: var(--charcoal);
}

/* STUDIO SECTION */
.studio-section { padding: 100px 0; }
.studio-grid { display: grid; grid-template-columns: 1.2fr 0.8fr; gap: 60px; }
.studio-body { font-size: 1.1rem; color: var(--steel); margin-top: 24px; line-height: 1.8; }
.sub-head { font-family: var(--font-mono); font-size: 0.85rem; font-weight: 700; letter-spacing: 0.15em; color: var(--gold-dark); margin-bottom: 24px; }
.industries-list { display: flex; flex-direction: column; gap: 16px; }
.ind-item { font-family: var(--font-sans); font-size: 1rem; font-weight: 800; padding-bottom: 12px; border-bottom: 1px solid var(--border-line); color: var(--charcoal); }
.ind-item span { font-family: var(--font-mono); color: var(--gold-dark); margin-right: 12px; font-size: 0.85rem; }

/* CONTACT PORTAL EXPERIENCE */
.contact-section { padding: 100px 0; }
.portal-wrapper { background: #FFFFFF; border: 1px solid var(--border-line); border-radius: var(--radius-lg); padding: 50px 40px; box-shadow: var(--shadow-lg); }
.portal-content { max-width: 700px; margin: 0 auto; }
.portal-title { font-family: var(--font-sans); font-size: 2.5rem; font-weight: 800; margin-bottom: 8px; color: var(--charcoal); }
.portal-sub { font-size: 0.95rem; color: var(--steel); margin-bottom: 36px; }

.portal-form { display: flex; flex-direction: column; gap: 20px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.f-group { display: flex; flex-direction: column; gap: 6px; }
.f-group label { font-family: var(--font-mono); font-size: 0.68rem; font-weight: 700; color: var(--steel); letter-spacing: 0.1em; }
.f-group input, .f-group select, .f-group textarea {
    background: #FAFAFA;
    border: 1px solid var(--border-line);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    color: var(--charcoal);
    font-family: var(--font-sans);
    font-size: 0.9rem;
    outline: none;
}
.f-group input:focus, .f-group select:focus, .f-group textarea:focus { border-color: var(--gold-dark); background: #FFFFFF; }

/* FOOTER */
.footer { border-top: 1px solid var(--border-line); padding: 40px 0; background: #FFFFFF; }
.footer-container { display: flex; justify-content: space-between; align-items: center; }
.footer-brand { display: flex; flex-direction: column; gap: 4px; }
.footer-desc { font-family: var(--font-mono); font-size: 0.68rem; font-weight: 700; color: var(--steel); letter-spacing: 0.1em; }
.footer-copy { font-family: var(--font-mono); font-size: 0.7rem; font-weight: 700; color: var(--steel); }

/* TOASTS */
.toast-container { position: fixed; bottom: 24px; right: 24px; display: flex; flex-direction: column; gap: 12px; z-index: 10000; }
.toast { background: #FFFFFF; border: 1px solid var(--gold-dark); padding: 14px 20px; border-radius: var(--radius-sm); color: var(--charcoal); font-family: var(--font-mono); font-size: 0.8rem; box-shadow: var(--shadow-lg); }

/* RESPONSIVE */
@media (max-width: 1024px) {
    .digital-twin-sticky-container { flex-direction: column; align-items: flex-start; justify-content: flex-end; }
    .hero-right-hud { align-self: flex-end; }
    .stage-nav-vertical { flex-direction: row; border-right: none; border-bottom: 2px solid var(--border-line); padding-bottom: 12px; }
    .systems-grid, .materials-grid { grid-template-columns: repeat(2, 1fr); }
    .hero-headline { font-size: 3rem; }
    .studio-grid { grid-template-columns: 1fr; }
    .panel-inner { grid-template-columns: 1fr; gap: 24px; }
}

@media (max-width: 640px) {
    .nav-links { display: none; }
    .systems-grid, .materials-grid { grid-template-columns: 1fr; }
    .hero-headline { font-size: 2.2rem; }
    .form-row { grid-template-columns: 1fr; }
    .cs-details-grid { grid-template-columns: 1fr; }
}