:root {
    /* Dark Theme (Default) */
    --bg-color: #0f172a;
    --text-color: #f8fafc;
    --text-secondary: #94a3b8;
    --primary-cyan: #38bdf8;
    --glow-amber: #f59e0b;
    --slate-800: #1e293b;
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --nav-bg: rgba(15, 23, 42, 0.8);
    --card-hover-glow: rgba(56, 189, 248, 0.2);
}

[data-theme="light"] {
    /* Light Theme */
    --bg-color: #f8fafc;
    --text-color: #0f172a;
    --text-secondary: #475569;
    --primary-cyan: #0284c7;
    --glow-amber: #d97706;
    --slate-800: #e2e8f0;
    --glass-bg: rgba(255, 255, 255, 0.8);
    --glass-border: rgba(15, 23, 42, 0.1);
    --nav-bg: rgba(248, 250, 252, 0.8);
    --card-hover-glow: rgba(2, 132, 199, 0.1);
}

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Navigation */
header.topbar {
    background: var(--nav-bg);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--glass-border);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.brand {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary-cyan);
    text-decoration: none;
    text-transform: uppercase;
    letter-spacing: 1px;
}

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

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    margin-left: 1.5rem;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: var(--primary-cyan);
}

/* Theme Toggle Button */
.theme-toggle {
    background: none;
    border: 1px solid var(--glass-border);
    color: var(--text-color);
    padding: 0.5rem;
    border-radius: 0.5rem;
    cursor: pointer;
    margin-left: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s;
    font-size: 1.2rem;
}

.theme-toggle:hover {
    background: var(--glass-border);
}

/* Sections */
section {
    padding: 5rem 0;
}

.hero {
    text-align: center;
    background: linear-gradient(rgba(15, 23, 42, 0.7), rgba(15, 23, 42, 0.7)), url('hero.png');
    background-size: cover;
    background-position: center;
    padding: 8rem 0;
    border-radius: 0 0 2rem 2rem;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    background: linear-gradient(to right, var(--primary-cyan), var(--glow-amber));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    color: var(--text-secondary);
}

/* Cards & Glassmorphism */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s, background-color 0.3s;
}

.glass-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 0 20px var(--card-hover-glow);
    border-color: var(--primary-cyan);
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

/* UI Elements */
.btn {
    display: inline-block;
    padding: 0.8rem 1.5rem;
    border-radius: 0.5rem;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
}

.btn-primary {
    background: var(--primary-cyan);
    color: white;
}

.btn-primary:hover {
    box-shadow: 0 0 15px var(--primary-cyan);
    transform: scale(1.05);
}

.btn-outline {
    border: 1px solid var(--primary-cyan);
    color: var(--primary-cyan);
}

/* Service Page Images */
.service-hero-img {
    width: 100%;
    height: 350px;
    object-fit: cover;
    object-position: center;
    border-radius: 1.5rem;
    margin-top: 2rem;
    border: 1px solid var(--glass-border);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

/* Footer */
footer {
    padding: 3rem 0;
    border-top: 1px solid var(--glass-border);
    text-align: center;
    color: var(--text-secondary);
}

/* Mobile */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .hero h1 {
        font-size: 2.5rem;
    }
}