/* Reset and base styles */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-text: #1f2937;
    --color-text-light: #6b7280;
    --color-background: #ffffff;
    --color-background-alt: #f9fafb;
    --color-border: #e5e7eb;
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    --max-width: 1100px;
    --spacing: 2rem;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    color: var(--color-text);
    background-color: var(--color-background);
    line-height: 1.6;
}

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

/* Header & Navigation */
header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--color-background);
    border-bottom: 1px solid var(--color-border);
    z-index: 100;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 1rem var(--spacing);
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    color: var(--color-text-light);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

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

/* Hero Section */
#hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 6rem var(--spacing) 4rem;
    background: var(--color-background-alt);
}

.hero-content h1 {
    font-size: clamp(2rem, 5vw, 3.5rem);
    font-weight: 700;
    margin-bottom: 1rem;
}

.highlight {
    color: var(--color-primary);
}

.tagline {
    font-size: 1.25rem;
    color: var(--color-text-light);
    margin-bottom: 2rem;
}

.cta-button {
    display: inline-block;
    background: var(--color-primary);
    color: white;
    padding: 0.875rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: background 0.2s, transform 0.2s;
}

.cta-button:hover {
    background: var(--color-primary-dark);
    transform: translateY(-2px);
}

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

section h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
    text-align: center;
}

/* About Section */
#about {
    background: var(--color-background);
}

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

.about-content p {
    color: var(--color-text-light);
    margin-bottom: 1rem;
}

/* Projects Section */
#projects {
    background: var(--color-background-alt);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.project-card {
    background: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: 12px;
    padding: 2rem;
    transition: transform 0.2s, box-shadow 0.2s;
}

.project-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.1);
}

.project-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.project-card p {
    color: var(--color-text-light);
    margin-bottom: 1.5rem;
}

.project-link {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 600;
}

.project-link:hover {
    text-decoration: underline;
}

/* Contact Section */
#contact {
    background: var(--color-background);
    text-align: center;
}

#contact p {
    color: var(--color-text-light);
    margin-bottom: 2rem;
}

/* Footer */
footer {
    background: var(--color-text);
    color: var(--color-background);
    padding: 2rem 0;
    text-align: center;
}

footer p {
    font-size: 0.875rem;
    opacity: 0.8;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-links {
        gap: 1rem;
    }

    section {
        padding: 3rem 0;
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }
}