/* CSS Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fafafa;
}

/* CSS Custom Properties */
:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #64748b;
    --accent-color: #f59e0b;
    --text-color: #1f2937;
    --text-light: #6b7280;
    --background: #ffffff;
    --background-alt: #f8fafc;
    --border-color: #e5e7eb;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius: 8px;
    --radius-lg: 12px;
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --container-max: 1200px;
    --header-height: 70px;
}

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 2rem); }
h4 { font-size: 1.125rem; }

p {
    margin-bottom: var(--spacing-md);
    color: var(--text-light);
}

.section-title {
    text-align: center;
    margin-bottom: var(--spacing-sm);
    color: var(--text-color);
}

.section-subtitle {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
    font-size: 1.125rem;
    color: var(--text-light);
}

/* Header and Navigation */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: var(--background);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    box-shadow: var(--shadow);
}

.nav {
    height: var(--header-height);
}

.nav-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.2s ease;
}

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

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

.nav-link {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.2s ease;
    position: relative;
}

.nav-link:hover,
.nav-link:focus {
    color: var(--primary-color);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width 0.2s ease;
}

.nav-link:hover::after,
.nav-link:focus::after {
    width: 100%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-md);
    min-width: 44px;
    min-height: 44px;
}

.nav-toggle span {
    width: 28px;
    height: 3px;
    background-color: var(--text-color);
    margin: 4px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    padding: calc(var(--header-height) + var(--spacing-2xl)) 0 var(--spacing-2xl);
    background: linear-gradient(135deg, var(--background) 0%, var(--background-alt) 100%);
}

.hero-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 80vh;
    text-align: center;
}

.hero-content {
    max-width: 600px;
}

.hero-title {
    margin-bottom: var(--spacing-md);
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xl);
    color: var(--text-light);
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.hero-image {
    order: 1;
    display: flex;
    justify-content: center;
}

.hero-placeholder {
    width: 300px;
    height: 300px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
    font-size: 1.125rem;
    box-shadow: var(--shadow-lg);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.2s ease;
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

/* About Section */
.about {
    padding: var(--spacing-2xl) 0;
    background-color: var(--background);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
    align-items: start;
}

.about-highlights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.highlight {
    text-align: center;
    padding: var(--spacing-lg);
    background-color: var(--background-alt);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

.highlight h3 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
}

/* Projects Section */
.projects {
    padding: var(--spacing-2xl) 0;
    background-color: var(--background-alt);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--spacing-xl);
}

.project-card {
    background-color: var(--background);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.project-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.project-image {
    height: 200px;
    background-color: var(--background-alt);
    display: flex;
    align-items: center;
    justify-content: center;
}

.project-placeholder {
    color: var(--text-light);
    font-weight: 500;
}

.project-content {
    padding: var(--spacing-lg);
}

.project-title {
    margin-bottom: var(--spacing-sm);
    color: var(--text-color);
}

.project-description {
    margin-bottom: var(--spacing-lg);
    color: var(--text-light);
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-lg);
}

.tag {
    background-color: var(--background-alt);
    color: var(--secondary-color);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius);
    font-size: 0.875rem;
    font-weight: 500;
}

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

.project-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

.project-link:hover {
    color: var(--primary-hover);
}

/* Contact Section */
.contact {
    padding: calc(var(--header-height) + var(--spacing-2xl)) 0 var(--spacing-2xl);
    background-color: var(--background);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-2xl);
    align-items: start;
}

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

.contact-item h3 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
}

.contact-item p,
.contact-item a {
    color: var(--text-light);
    text-decoration: none;
    transition: color 0.2s ease;
}

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

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

.social-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

.social-link:hover {
    color: var(--primary-hover);
}

.contact-form {
    background-color: var(--background-alt);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
}

/* Form Styles */
.form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

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

.form-group label {
    font-weight: 500;
    color: var(--text-color);
}

.form-group input,
.form-group textarea {
    padding: var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-family: inherit;
    font-size: 1rem;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* Footer */
.footer {
    padding: var(--spacing-xl) 0;
    background-color: var(--text-color);
    color: white;
    text-align: center;
}

.footer p {
    margin: 0;
    color: rgba(255, 255, 255, 0.8);
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }

    .nav-toggle {
        display: flex;
    }

    .hero-container {
        min-height: 70vh;
        padding-top: var(--spacing-xl);
    }

    .hero-buttons {
        justify-content: center;
    }

    .hero-placeholder {
        width: 200px;
        height: 200px;
    }

    .about-content {
        text-align: center;
    }

    .about-highlights {
        grid-template-columns: 1fr;
    }

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

    .contact-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-xl);
    }

    .contact-form {
        padding: var(--spacing-lg);
    }

    .container {
        padding: 0 var(--spacing-sm);
    }
}

@media (max-width: 480px) {
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 300px;
        padding: var(--spacing-md) var(--spacing-lg);
    }

    .project-links {
        flex-direction: column;
    }

    .social-links {
        flex-direction: column;
    }
}

/* Dark mode styles */
@media (prefers-color-scheme: dark) {
    :root {
        --text-color: #f3f4f6;
        --text-light: #9ca3af;
        --background: #111827;
        --background-alt: #1f2937;
        --border-color: #374151;
    }

    /* Additional dark mode adjustments if needed */
    body {
        background-color: var(--background);
        color: var(--text-color);
    }

    .header {
        background-color: var(--background);
        border-bottom-color: var(--border-color);
    }

    .footer {
        background-color: var(--background-alt);
    }

    .highlight {
        background-color: var(--background-alt);
        border-color: var(--border-color);
    }

    .contact-form {
        background-color: var(--background-alt);
        border-color: var(--border-color);
    }
}

/* Utility Classes */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}