/* --- Variables & Reset --- */
:root {
    /* Light Theme Defaults */
    --bg-color: #ffffff;
    --bg-alt: #f8f9fa;
    --text-primary: #111111;
    --text-secondary: #555555;
    --accent: #2563eb; /* Modern Blue */
    --accent-hover: #1d4ed8;
    --card-bg: #ffffff;
    --border: #e5e7eb;
    --nav-height: 80px;
    --transition: all 0.3s ease;
}

/* Dark Mode Override (Automatic based on system settings) */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #0f0f0f;
        --bg-alt: #1a1a1a;
        --text-primary: #f0f0f0;
        --text-secondary: #a0a0a0;
        --accent: #3b82f6;
        --accent-hover: #60a5fa;
        --card-bg: #1e1e1e;
        --border: #333333;
    }
}

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

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

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

/* --- Layout Utilities --- */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.section { padding: 80px 0; }
.bg-alt { background-color: var(--bg-alt); }

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 60px;
    font-weight: 800;
}

/* --- Navigation --- */
.navbar {
    height: var(--nav-height);
    display: flex;
    align-items: center;
    position: fixed;
    width: 100%;
    top: 0;
    background: rgba(var(--bg-color), 0.9);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid var(--border);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: -1px;
}
.logo span { color: var(--accent); }

.nav-links { display: flex; gap: 30px; align-items: center; }
.nav-links a { font-weight: 500; font-size: 0.95rem; transition: var(--transition); }
.nav-links a:hover { color: var(--accent); }

.btn-primary {
    background-color: var(--accent);
    color: #fff !important;
    padding: 10px 24px;
    border-radius: 50px;
    font-weight: 600;
    transition: var(--transition);
}
.btn-primary:hover { background-color: var(--accent-hover); transform: translateY(-2px); }

.btn-secondary {
    border: 2px solid var(--text-primary);
    padding: 10px 24px;
    border-radius: 50px;
    font-weight: 600;
    margin-left: 10px;
    transition: var(--transition);
}
.btn-secondary:hover { background-color: var(--text-primary); color: var(--bg-color); }

.hamburger { display: none; cursor: pointer; }
.hamburger span { display: block; width: 25px; height: 3px; background: var(--text-primary); margin: 5px 0; }

/* --- Hero Section --- */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding-top: var(--nav-height);
    background: radial-gradient(circle at center, var(--bg-alt) 0%, var(--bg-color) 100%);
}

.hero h1 {
    font-size: 4rem;
    line-height: 1.1;
    margin-bottom: 20px;
    font-weight: 800;
}

.highlight {
    background: linear-gradient(120deg, var(--accent), #8b5cf6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 40px;
}

/* --- Portfolio Grid --- */
.portfolio-filters {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.filter-btn {
    background: transparent;
    border: 1px solid var(--border);
    padding: 8px 20px;
    border-radius: 30px;
    cursor: pointer;
    color: var(--text-secondary);
    transition: var(--transition);
}

.filter-btn.active, .filter-btn:hover {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 24px;
}

.portfolio-item {
    position: relative;
    aspect-ratio: 4/3;
    border-radius: 12px;
    overflow: hidden;
    cursor: pointer;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

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

.portfolio-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 20px;
    background: linear-gradient(to top, rgba(0,0,0,0.8), transparent);
    color: #fff;
    transform: translateY(100%);
    transition: transform 0.3s ease;
}

.portfolio-item:hover img { transform: scale(1.1); }
.portfolio-item:hover .portfolio-overlay { transform: translateY(0); }

/* --- Services --- */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.service-card {
    background: var(--card-bg);
    padding: 40px;
    border-radius: 16px;
    border: 1px solid var(--border);
    transition: var(--transition);
}

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

.service-card h3 { margin-bottom: 15px; font-size: 1.5rem; }
.service-card p { color: var(--text-secondary); }

/* --- Footer --- */
footer {
    background: var(--bg-alt);
    padding: 60px 0 20px;
    border-top: 1px solid var(--border);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h3 { margin-bottom: 20px; }
.footer-col h4 { margin-bottom: 15px; color: var(--accent); }
.footer-col p { color: var(--text-secondary); margin-bottom: 10px; }
.social-links a { margin-right: 15px; font-weight: 600; }

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid var(--border);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* --- Responsive Mobile --- */
@media (max-width: 768px) {
    .hero h1 { font-size: 2.5rem; }
    
    .hamburger { display: block; }
    
    .nav-links {
        position: fixed;
        top: var(--nav-height);
        left: -100%;
        width: 100%;
        height: calc(100vh - var(--nav-height));
        background: var(--bg-color);
        flex-direction: column;
        justify-content: center;
        transition: 0.4s ease;
        border-top: 1px solid var(--border);
    }
    
    .nav-links.active { left: 0; }
    
    .portfolio-grid { grid-template-columns: 1fr; }
}