/* DNA Foundations - Main Stylesheet */

/* MARK: CSS Variables - Core design tokens */
:root {
    --color-primary: #1a1a1a;
    --color-secondary: #2d2d2d;
    --color-accent: #d35400;
    --color-text: #333;
    --color-text-light: #666;
    --color-bg: #f5f5f5;
    --color-white: #fff;
    --color-concrete: #e0e0e0;
    
    --font-main: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 4rem;
    --spacing-xl: 6rem;
    
    --max-width: 1200px;
    --border-radius: 4px;
    --transition: 0.3s ease;
}

/* MARK: Reset & Base - Foundation styles */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-main);
    font-size: 16px;
    line-height: 1.6;
    color: var(--color-text);
    background: var(--color-bg);
}

img {
    max-width: 100%;
    height: auto;
}

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition);
}

a:hover {
    color: var(--color-primary);
}

.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-sm);
}

/* MARK: Header - Navigation and branding */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: var(--color-primary);
    padding: var(--spacing-sm) 0;
}

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

.logo {
    display: flex;
    flex-direction: column;
    line-height: 1.1;
    text-decoration: none;
}

.logo-text {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--color-white);
    letter-spacing: 0.1em;
}

.logo-sub {
    font-size: 0.75rem;
    color: var(--color-accent);
    text-transform: uppercase;
    letter-spacing: 0.2em;
}

.nav {
    display: flex;
    gap: var(--spacing-md);
}

.nav a {
    color: var(--color-white);
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: var(--spacing-xs) 0;
    border-bottom: 2px solid transparent;
    transition: border-color var(--transition);
}

.nav a:hover {
    color: var(--color-white);
    border-bottom-color: var(--color-accent);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-white);
    transition: var(--transition);
}

/* MARK: Hero - Main landing section */
.hero {
    background: linear-gradient(135deg, var(--color-secondary) 0%, var(--color-primary) 100%);
    color: var(--color-white);
    padding: calc(var(--spacing-xl) + 60px) 0 var(--spacing-xl);
    min-height: 70vh;
    display: flex;
    align-items: center;
}

.hero h1 {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-sm);
}

.hero .tagline {
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.25em;
    color: var(--color-accent);
    margin-bottom: var(--spacing-xs);
    font-weight: 600;
}

.hero p {
    font-size: 1.1rem;
    color: var(--color-concrete);
    margin-bottom: var(--spacing-md);
    max-width: 500px;
}

.btn {
    display: inline-block;
    background: var(--color-accent);
    color: var(--color-white);
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 1rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border-radius: var(--border-radius);
    transition: background var(--transition), transform var(--transition);
}

.btn:hover {
    background: #b84700;
    color: var(--color-white);
    transform: translateY(-2px);
}

/* MARK: Services - Service offerings grid */
.services {
    padding: var(--spacing-xl) 0;
    background: var(--color-white);
}

.services h2,
.about h2,
.contact h2 {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
    text-align: center;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-md);
}

.service-card {
    background: var(--color-bg);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    border-left: 4px solid var(--color-accent);
    transition: transform var(--transition), box-shadow var(--transition);
}

.service-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.service-icon {
    font-size: 2rem;
    margin-bottom: var(--spacing-sm);
    color: var(--color-secondary);
}

.service-card h3 {
    font-size: 1.25rem;
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
}

.service-card p {
    color: var(--color-text-light);
    font-size: 0.95rem;
}

/* MARK: About - Company information */
.about {
    padding: var(--spacing-xl) 0;
    background: var(--color-concrete);
}

.about-content {
    max-width: 700px;
    margin: 0 auto;
    text-align: center;
}

.about-content p {
    margin-bottom: var(--spacing-sm);
    color: var(--color-text);
}

.about-list {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-sm) var(--spacing-md);
    margin-top: var(--spacing-md);
}

.about-list li {
    background: var(--color-white);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    color: var(--color-secondary);
    font-weight: 500;
}

/* MARK: Contact - Contact details */
.contact {
    padding: var(--spacing-xl) 0;
    background: var(--color-white);
}

.contact > .container {
    text-align: center;
}

.contact > .container > p {
    color: var(--color-text-light);
    margin-bottom: var(--spacing-lg);
}

.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-md);
    max-width: 800px;
    margin: 0 auto;
}

.contact-item {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.contact-item strong {
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-light);
}

.contact-item span,
.contact-item a {
    font-size: 1.1rem;
    color: var(--color-primary);
    font-weight: 500;
}

.contact-item a:hover {
    color: var(--color-accent);
}

/* MARK: Footer - Site footer */
.footer {
    background: var(--color-primary);
    color: var(--color-concrete);
    padding: var(--spacing-md) 0;
    text-align: center;
}

.footer p {
    font-size: 0.85rem;
}

/* MARK: Mobile - Responsive breakpoints */
@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }
    
    .nav {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--color-primary);
        padding: 0 var(--spacing-sm);
        max-height: 0;
        overflow: hidden;
        transition: max-height var(--transition), padding var(--transition);
    }
    
    .nav.active {
        max-height: 300px;
        padding: var(--spacing-sm);
    }
    
    .nav a {
        padding: var(--spacing-sm) 0;
        border-bottom: 1px solid var(--color-secondary);
    }
    
    .nav a:last-child {
        border-bottom: none;
    }
    
    .hero {
        min-height: 60vh;
        padding-top: calc(var(--spacing-lg) + 60px);
    }
    
    .services,
    .about,
    .contact {
        padding: var(--spacing-lg) 0;
    }
    
    .services h2,
    .about h2,
    .contact h2 {
        margin-bottom: var(--spacing-md);
    }
    
    .contact-info {
        grid-template-columns: 1fr 1fr;
        text-align: left;
    }
}

@media (max-width: 480px) {
    .contact-info {
        grid-template-columns: 1fr;
    }
    
    .about-list {
        flex-direction: column;
        align-items: center;
    }
}