/* 
   RVTEC Institutional Site 
   Theme: Enterprise Modern (Dark Navy/Slate + Clean White)
*/

:root {
    /* Colors */
    --primary: #0f172a;       /* Dark Slate/Navy */
    --secondary: #334155;     /* Lighter Slate */
    --accent: #0ea5e9;        /* Tech Blue (Subtle highlights) */
    --text-main: #1e293b;     /* Dark Grey for text */
    --text-light: #64748b;    /* Muted Grey */
    --bg-light: #f8fafc;      /* Very light grey background */
    --white: #ffffff;
    
    /* Typography */
    --font-heading: 'Roboto', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-body: 'Roboto', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    
    /* Spacing */
    --container-width: 1200px;
    --section-padding: 100px 0;
}

/* Reset & Base */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font-body);
    color: var(--text-main);
    line-height: 1.6;
    background-color: var(--white);
    overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { text-decoration: none; color: inherit; transition: 0.3s; }
ul { list-style: none; }

/* Utilities */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 4px;
    font-weight: 500;
    letter-spacing: 0.5px;
    cursor: pointer;
}
.btn-primary {
    background: var(--primary);
    color: var(--white);
    border: 1px solid var(--primary);
}
.btn-primary:hover {
    background: transparent;
    color: var(--primary);
}
.btn-outline {
    border: 1px solid var(--white);
    color: var(--white);
}
.btn-outline:hover {
    background: var(--white);
    color: var(--primary);
}

/* Typography Utilities */
h1, h2, h3, h4 { color: var(--primary); margin-bottom: 20px; line-height: 1.2; }
h2 { font-size: 2.5rem; font-weight: 700; letter-spacing: -0.5px; }
.section-title {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 60px;
}
.section-title span {
    display: block;
    color: var(--accent);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    font-weight: 600;
    margin-bottom: 10px;
}

/* Header */
header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0,0,0,0.05);
    padding: 15px 0;
}
.nav-wrapper {
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.logo img {
    height: 40px; /* Adjust based on SVG */
}
nav ul { display: flex; gap: 30px; }
nav a { font-size: 0.95rem; font-weight: 500; color: var(--secondary); }
nav a:hover { color: var(--primary); }

/* Hero Section */
.hero {
    height: 100vh;
    min-height: 600px;
    background: linear-gradient(rgba(15, 23, 42, 0.8), rgba(15, 23, 42, 0.8)), url('../images/hero-bg.png');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--white);
    padding-top: 80px; /* Offset fixed header */
}
.hero-content h1 {
    font-size: 3.5rem;
    color: var(--white);
    margin-bottom: 20px;
    max-width: 900px;
}
.hero-content p {
    font-size: 1.25rem;
    color: #cbd5e1;
    margin-bottom: 40px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

/* Animations (Intersection Observer Targets) */
.hidden {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s ease-out;
}
.show {
    opacity: 1;
    transform: translateY(0);
}
.stagger-delay-1 { transition-delay: 0.1s; }
.stagger-delay-2 { transition-delay: 0.2s; }
.stagger-delay-3 { transition-delay: 0.3s; }

/* About Section */
.about { padding: var(--section-padding); background: var(--white); }
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}
.about-text p { margin-bottom: 20px; font-size: 1.05rem; color: var(--text-light); }
.about-stat {
    display: flex;
    gap: 40px;
    margin-top: 30px;
}
.stat-item h3 { font-size: 2.5rem; margin-bottom: 5px; color: var(--primary); }
.stat-item span { font-size: 0.9rem; color: var(--text-light); }

/* Services Section */
.services { padding: var(--section-padding); background: var(--bg-light); }
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}
.service-card {
    background: var(--white);
    padding: 40px;
    border-radius: 8px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
    border-top: 3px solid transparent;
    transition: 0.3s;
}
.service-card:hover {
    transform: translateY(-5px);
    border-top: 3px solid var(--accent);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}
.service-icon {
    font-size: 2rem;
    margin-bottom: 20px;
    color: var(--accent);
}
.service-card h3 { font-size: 1.3rem; margin-bottom: 15px; }
.service-card p { font-size: 0.95rem; color: var(--text-light); }
.service-list { margin-top: 15px; padding-left: 0; list-style: none; }
.service-list li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: var(--secondary);
}
.service-list li::before {
    content: "•";
    color: var(--accent);
    position: absolute;
    left: 0;
}

/* Methodology */
.methodology { padding: var(--section-padding); background: var(--primary); color: var(--white); }
.methodology h2, .methodology h3 { color: var(--white); }
.methodology .section-title span { color: var(--accent); opacity: 0.9; }
.steps-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    text-align: center;
    margin-top: 60px;
}
.step-item { position: relative; padding: 20px; }
.step-number {
    font-size: 4rem;
    font-weight: 700;
    color: rgba(255,255,255,0.1);
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    z-index: 0;
}
.step-content { position: relative; z-index: 1; margin-top: 30px; }
.step-content h4 { color: var(--white); margin-bottom: 10px; }
.step-content p { font-size: 0.9rem; color: #cbd5e1; }

/* Contact / Footer */
.contact { padding: 80px 0; background: var(--white); text-align: center; }
.contact-box {
    background: var(--bg-light);
    padding: 60px;
    border-radius: 12px;
    display: inline-block;
    width: 100%;
    max-width: 800px;
}
footer {
    background: var(--primary);
    color: #64748b;
    padding: 40px 0;
    text-align: center;
    font-size: 0.9rem;
    border-top: 1px solid rgba(255,255,255,0.05);
}

/* Responsive */
@media (max-width: 768px) {
    h1 { font-size: 2.5rem; }
    .hero-content p { font-size: 1rem; }
    .steps-grid { grid-template-columns: 1fr; gap: 40px; }
    .about-grid { grid-template-columns: 1fr; }
    nav { display: none; /* Implement mobile menu if needed, simplified for speed */ }
}