/* VENJOIN V9: CORPORATE LIGHT THEME ARCHITECTURE */
:root {
    /* Primary Light Mode Palette */
    --bg-main: #f8fafc;
    --bg-secondary: #ffffff;
    --accent-blue: #2563eb;
    --accent-blue-hover: #1d4ed8;
    --accent-orange: #f97316;
    
    /* Typography Palette */
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    
    /* Borders & Glass */
    --glass-bg: rgba(255, 255, 255, 0.85);
    --glass-border: rgba(148, 163, 184, 0.2);
    --shadow-soft: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    --shadow-heavy: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);

    /* Fonts */
    --font-main: 'Inter', sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    --transition: all 0.25s ease-in-out;
}

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

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

/* Base Typography */
h1, h2, h3, h4 {
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.02em;
    color: var(--text-primary);
}

.hud-label {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--accent-blue);
    margin-bottom: 12px;
    display: block;
    font-weight: 700;
}
.hud-label.center { text-align: center; }

/* Structural Grid Rules (UNBREAKABLE) */
.container {
    width: 100%;
    max-width: 1300px;
    margin: 0 auto;
    padding: 0 24px;
}
.relative { position: relative; }
.z-10 { z-index: 10; }
.mt-4 { margin-top: 40px; }

/* Buttons */
a { text-decoration: none; }

.btn-primary, .btn-secondary, .btn-primary-small {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 28px;
    font-size: 0.9rem;
    font-weight: 700;
    letter-spacing: 0.5px;
    border-radius: 6px;
    transition: var(--transition);
    cursor: pointer;
    text-transform: uppercase;
}
.btn-primary { 
    background: var(--accent-blue); 
    color: #ffffff; 
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25); 
    border: none;
}
.btn-primary:hover { 
    background: var(--accent-blue-hover); 
    transform: translateY(-2px); 
    box-shadow: 0 6px 16px rgba(37, 99, 235, 0.35);
}
.btn-secondary { 
    background: var(--bg-secondary); 
    color: var(--text-primary); 
    border: 1px solid var(--glass-border); 
}
.btn-secondary:hover { 
    background: #f1f5f9; 
}
.btn-primary-small { 
    padding: 10px 20px; 
    font-size: 0.8rem; 
    background: var(--accent-blue); 
    color: #white; 
}

/* Light Navigation */
nav {
    position: fixed;
    top: 0; 
    width: 100%;
    z-index: 1000;
    transition: var(--transition);
    padding: 20px 0;
}
nav.scrolled {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 15px 0;
    box-shadow: var(--shadow-soft);
    border-bottom: 1px solid var(--glass-border);
}
.nav-container { display: flex; justify-content: space-between; align-items: center; }
.logo { font-size: 1.8rem; font-weight: 900; letter-spacing: -0.05em; color: var(--text-primary); }
.logo span { color: var(--accent-blue); }
.nav-links { display: flex; list-style: none; gap: 32px; align-items: center; }
.nav-links li a { 
    color: var(--text-secondary); 
    font-size: 0.9rem; 
    font-weight: 600; 
    letter-spacing: 0.5px; 
    transition: var(--transition); 
}
.nav-links li a:hover { color: var(--accent-blue); }

/* V9 Light Glass Cards */
.glass-card {
    background: var(--bg-secondary);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 32px;
    box-shadow: var(--shadow-soft);
    transition: var(--transition);
}
.glass-card:hover {
    box-shadow: var(--shadow-heavy);
    transform: translateY(-4px);
}

/* Sections */
.section { padding: 100px 0; }
.dark-section { background: #ffffff; border-top: 1px solid var(--glass-border); border-bottom: 1px solid var(--glass-border); }
.section-header { text-align: center; margin-bottom: 64px; max-width: 800px; margin-left: auto; margin-right: auto;}
.section-header h2 { font-size: 2.8rem; margin-bottom: 16px; color: var(--text-primary); }
.section-header p { font-size: 1.1rem; color: var(--text-secondary); }
.divider { height: 4px; width: 60px; background: var(--accent-blue); margin: 24px 0; border-radius: 2px;}
.divider.center { margin: 24px auto; }

/* Hero Light V9 */
.hero {
    min-height: 90vh;
    display: flex;
    align-items: center;
    position: relative;
    background: #ffffff; /* Fallback */
}
.hero-overlay { 
    position: absolute; 
    top:0; left:0; width:100%; height:100%; 
    background: linear-gradient(90deg, rgba(255,255,255,0.95) 40%, rgba(255,255,255,0.7) 100%); 
}
.hero-content { position: relative; max-width: 700px; z-index: 2;}
.hero-title { font-size: 4.8rem; font-weight: 900; letter-spacing: -0.04em; line-height: 1; margin-bottom: 24px; color: var(--text-primary);}
.hero-desc { font-size: 1.25rem; color: var(--text-secondary); margin-bottom: 40px; line-height: 1.7;}
.hero-buttons { display: flex; gap: 16px; }

/* V9 Grid Architecture */
.cls-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.cls-card h3 { font-size: 1.4rem; margin-bottom: 16px; color: var(--text-primary); }
.cls-card p { color: var(--text-secondary); font-size: 1rem; line-height: 1.6; margin-bottom: 24px;}
.cls-card img { border-radius: 6px; border: 1px solid var(--glass-border); margin-bottom: 24px; width: 100%; height: 200px; object-fit: cover; }

/* Heavy Process Maps */
.steel-container { display: grid; grid-template-columns: 2fr 1fr; gap: 40px; }
.process-map { background: var(--bg-secondary); padding: 24px; border: 1px solid var(--glass-border); border-radius: 12px; position:relative; box-shadow: var(--shadow-soft); }
.process-img { width: 100%; border-radius: 8px; display: block; }
.hotspot { 
    position: absolute; width: 28px; height: 28px; 
    background: rgba(37, 99, 235, 0.2); border: 2px solid var(--accent-blue); 
    border-radius: 50%; cursor: pointer; animation: pulse-light 2s infinite; 
    display:flex; align-items:center; justify-content:center; 
}
.hotspot-number { font-family: var(--font-mono); font-size: 11px; color: var(--accent-blue); font-weight: 800;}
.hotspot:hover { background: var(--accent-blue); transform: scale(1.15); }
.hotspot:hover .hotspot-number { color: #fff; }
@keyframes pulse-light { 0% { box-shadow: 0 0 0 0 rgba(37, 99, 235, 0.4); } 70% { box-shadow: 0 0 0 15px rgba(37, 99, 235, 0); } 100% { box-shadow: 0 0 0 0 rgba(37, 99, 235, 0); } }

/* Light ROI Calc */
.roi-panel { background: var(--bg-secondary); padding: 32px; border-radius: 12px; border: 1px solid var(--glass-border); box-shadow: var(--shadow-soft); }
.input-group { margin-bottom: 24px; }
.input-group label { display: block; font-family:var(--font-mono); font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 10px; font-weight: 700;}
.input-group input { 
    width: 100%; background: #f8fafc; border: 1px solid #cbd5e1; 
    color: var(--text-primary); padding: 14px; font-family: var(--font-mono); 
    border-radius: 6px; font-size: 1rem; transition: var(--transition);
}
.input-group input:focus { outline: none; border-color: var(--accent-blue); box-shadow: 0 0 0 3px rgba(37,99,235,0.1); }
.result-box { margin-top: 32px; padding: 24px; background: #eff6ff; border: 1px dashed #93c5fd; border-radius: 8px; text-align: center; }
.result-val { font-size: 2.8rem; color: var(--accent-blue); font-weight: 900; font-family: var(--font-mono); letter-spacing: -1px; }

/* Tech Spec Table Light */
.spec-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; margin-top: 60px; }
.data-table { width: 100%; border-collapse: collapse; margin-top: 24px; font-family: var(--font-mono); font-size: 0.9rem;}
.data-table th, .data-table td { padding: 16px; border-bottom: 1px solid var(--glass-border); text-align: left; color: var(--text-primary);}
.data-table th { color: var(--text-secondary); font-weight: 700; text-transform: uppercase; background: #f8fafc; border-top: 1px solid var(--glass-border);}

/* Light FAQ */
.faq-card { background: var(--bg-secondary); border: 1px solid var(--glass-border); padding: 28px; border-radius: 8px; margin-bottom: 16px; cursor: pointer; transition: var(--transition); box-shadow: 0 1px 3px rgba(0,0,0,0.02);}
.faq-card:hover { border-color: #cbd5e1; box-shadow: var(--shadow-soft); }
.faq-title { font-size: 1.15rem; color: var(--text-primary); font-weight: 700; margin-bottom: 0; display:flex; justify-content:space-between; align-items:center; }
.faq-body { height: 0; overflow: hidden; opacity: 0; transition: var(--transition); color: var(--text-secondary); font-size: 1rem; margin-top: 0; line-height: 1.6;}
.faq-card.active .faq-body { height: auto; opacity: 1; margin-top: 20px; border-top: 1px dashed var(--glass-border); padding-top: 20px;}
.faq-icon { color: var(--accent-blue); font-size: 1.4rem; font-weight: 300; transition: 0.3s; }
.faq-card.active .faq-icon { transform: rotate(45deg); }
.search-box { width: 100%; padding: 20px 24px; font-size: 1.1rem; background: var(--bg-secondary); border: 1px solid #cbd5e1; color: var(--text-primary); border-radius: 8px; margin-bottom: 48px; transition: var(--transition); box-shadow: var(--shadow-soft);}
.search-box:focus { outline: none; border-color: var(--accent-blue); box-shadow: 0 0 0 4px rgba(37,99,235,0.1); }

/* Footer */
.footer { background: #0f172a; padding: 60px 0 30px; border-top: 1px solid var(--glass-border); margin-top: 80px;}
.copyright { text-align: center; color: #94a3b8; font-size: 0.85rem; font-weight: 500; letter-spacing: 0.5px;}

/* Builder Light Theme Customizations */
.builder-container { display: flex; gap: 40px; margin-top: 120px; height: 80vh; }
.sidebar { width: 380px; background: var(--bg-secondary); border: 1px solid var(--glass-border); border-radius: 12px; padding: 24px; overflow-y: auto; box-shadow: var(--shadow-soft); }
.canvas { 
    flex: 1; background: #ffffff; border: 1px dashed #cbd5e1; border-radius: 12px; position: relative; overflow: hidden; 
    display: flex; align-items: center; justify-content: center; 
    background-image: radial-gradient(#e2e8f0 1.5px, transparent 0); background-size: 24px 24px; 
}
.draggable { 
    background: #f8fafc; padding: 16px; border: 1px solid var(--glass-border); border-radius: 8px; 
    margin-bottom: 12px; cursor: grab; display: flex; align-items: center; gap: 16px; transition: 0.2s;
}
.draggable:hover { background: #ffffff; border-color: #cbd5e1; box-shadow: var(--shadow-soft);}
.draggable img { width: 44px; border-radius: 6px; border: 1px solid var(--glass-border); background: #fff;}
.canvas-module { position: absolute; background: #ffffff; border: 1px solid var(--accent-blue); padding: 12px; border-radius: 6px; color: var(--text-primary); display:flex; flex-direction:column; align-items:center; cursor: move; min-width: 100px; box-shadow: var(--shadow-heavy);}
.canvas-module img { width: 64px; margin-bottom: 8px; border-radius: 4px;}
#stats-bar { position: absolute; bottom: 0; width: 100%; background: #ffffff; padding: 20px; display: flex; justify-content: space-around; font-family: var(--font-mono); border-top: 1px solid #e2e8f0; font-weight: 700; color: var(--text-secondary); box-shadow: 0 -4px 10px rgba(0,0,0,0.02);}

/* Responsive */
@media (max-width: 992px) {
    .cls-grid { grid-template-columns: 1fr; }
    .steel-container, .spec-grid { grid-template-columns: 1fr; }
    .hero-title { font-size: 3.5rem; }
    .builder-container { flex-direction: column; height: auto; }
    .sidebar { width: 100%; height: 300px; }
    .canvas { height: 600px; }
}