/* ============================================
   CSS Reset & Base Styles
   ============================================ */

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

:root {
    /* Color Palette */
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --secondary-color: #64748b;
    --text-color: #1e293b;
    --text-light: #64748b;
    --bg-color: #ffffff;
    --bg-light: #f8fafc;
    --border-color: #e2e8f0;
    --accent-color: #0ea5e9;
    
    /* Typography */
    --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-size-base: 16px;
    --line-height-base: 1.6;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    
    /* Transitions */
    --transition-base: 0.2s ease-in-out;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
    color: var(--text-color);
    background-color: var(--bg-color);
}

/* ============================================
   Typography
   ============================================ */

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    color: var(--text-color);
}

h1 {
    font-size: 2rem;
}

h2 {
    font-size: 1.75rem;
}

h3 {
    font-size: 1.5rem;
}

h4 {
    font-size: 1.25rem;
}

p {
    margin-bottom: var(--spacing-sm);
}

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

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

/* ============================================
   Container & Layout
   ============================================ */

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

section {
    padding: var(--spacing-xl) 0;
}

/* ============================================
   Navigation
   ============================================ */

.navbar {
    background-color: var(--bg-color);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: var(--spacing-sm) 0;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

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

.nav-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
    gap: 4px;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--text-color);
    transition: all var(--transition-base);
    border-radius: 2px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
    align-items: center;
}

.nav-link {
    color: var(--text-color);
    font-weight: 500;
    padding: var(--spacing-xs) 0;
    position: relative;
}

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

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--primary-color);
}

/* ============================================
   Buttons
   ============================================ */

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 500;
    text-align: center;
    border-radius: var(--radius-md);
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
}

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

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

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

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

.btn-outline {
    background-color: transparent;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

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

/* ============================================
   Hero Section
   ============================================ */

.hero {
    background: linear-gradient(135deg, var(--bg-light) 0%, var(--bg-color) 100%);
    padding: var(--spacing-2xl) 0;
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-md);
    color: var(--text-color);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-light);
    margin-bottom: var(--spacing-xl);
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

/* ============================================
   Features Section
   ============================================ */

.features {
    background-color: var(--bg-color);
}

.features h2 {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

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

.feature-card {
    background-color: var(--bg-light);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
}

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

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

/* ============================================
   About Section
   ============================================ */

.about-section {
    background-color: var(--bg-color);
}

.about-content {
    margin-bottom: var(--spacing-xl);
}

.about-bio {
    max-width: 800px;
    margin: 0 auto;
}

.about-bio p {
    margin-bottom: var(--spacing-md);
    line-height: 1.8;
}

.skills-section {
    margin-top: var(--spacing-2xl);
}

.skills-section h2 {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.skill-category {
    background-color: var(--bg-light);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

.skill-category h3 {
    color: var(--primary-color);
    margin-bottom: var(--spacing-md);
    font-size: 1.25rem;
}

.skill-list {
    list-style: none;
}

.skill-list li {
    padding: var(--spacing-xs) 0;
    padding-left: var(--spacing-md);
    position: relative;
}

.skill-list li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

/* ============================================
   Case Studies Section
   ============================================ */

.case-studies-section {
    background-color: var(--bg-color);
}

.case-studies-section h1 {
    text-align: center;
    margin-bottom: var(--spacing-md);
}

.section-intro {
    text-align: center;
    max-width: 700px;
    margin: 0 auto var(--spacing-xl);
    color: var(--text-light);
    font-size: 1.1rem;
}

.case-studies-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--spacing-lg);
}

.case-study-card {
    background-color: var(--bg-light);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
    display: flex;
    flex-direction: column;
    border-left: 4px solid var(--primary-color);
}

.case-study-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.case-study-card.technical {
    border-left-color: var(--primary-color);
}

.case-study-card.analytical {
    border-left-color: var(--accent-color);
}

.project-badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: var(--spacing-sm);
}

.technical-badge {
    background-color: rgba(37, 99, 235, 0.1);
    color: var(--primary-color);
}

.analytical-badge {
    background-color: rgba(14, 165, 233, 0.1);
    color: var(--accent-color);
}

/* Case Study Image Placeholder */
.case-image {
    margin: 0 0 var(--spacing-md) 0;
    padding: 0;
    width: 100%;
    border-radius: var(--radius-md);
    overflow: hidden;
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    position: relative;
    aspect-ratio: 16 / 9;
}

.case-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
    display: block;
    transition: transform var(--transition-base);
    background-color: var(--bg-light);
    /* Fallback for missing images */
    background-image: linear-gradient(135deg, #f1f5f9 0%, #e2e8f0 100%);
}

.case-image:hover img {
    transform: scale(1.02);
}

.vis-caption {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.6), transparent);
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin: 0;
    opacity: 0;
    transition: opacity var(--transition-base);
}

.case-image:hover .vis-caption {
    opacity: 1;
}

.case-study-card h3 {
    margin-bottom: var(--spacing-sm);
    color: var(--text-color);
}

.case-description {
    color: var(--text-light);
    margin-bottom: var(--spacing-md);
    flex-grow: 1;
    line-height: 1.7;
}

.case-tools {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.tool-tag {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background-color: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    color: var(--text-color);
}

.case-links {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

/* ============================================
   Contact Section
   ============================================ */

.contact-section {
    background-color: var(--bg-color);
}

.contact-section h1 {
    text-align: center;
    margin-bottom: var(--spacing-md);
}

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
    max-width: 1000px;
    margin: 0 auto;
}

.contact-form-container,
.contact-info {
    background-color: var(--bg-light);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

.contact-form-container h2,
.contact-info h2 {
    margin-bottom: var(--spacing-lg);
    color: var(--text-color);
}

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

.form-group {
    display: flex;
    flex-direction: column;
}

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

.required {
    color: #ef4444;
}

.form-group input,
.form-group textarea {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: var(--font-primary);
    font-size: 1rem;
    transition: border-color var(--transition-base);
}

.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);
}

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

.contact-item h3 {
    font-size: 1.1rem;
    margin-bottom: var(--spacing-xs);
    color: var(--primary-color);
}

.contact-item p {
    margin: 0;
}

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

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

/* ============================================
   Footer
   ============================================ */

.footer {
    background-color: var(--text-color);
    color: white;
    padding: var(--spacing-lg) 0;
    margin-top: var(--spacing-2xl);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

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

.social-link {
    color: white;
    font-weight: 500;
    transition: color var(--transition-base);
}

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

/* ============================================
   Mobile Responsive Styles
   ============================================ */

@media (max-width: 768px) {
    /* Typography */
    h1 {
        font-size: 1.75rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.1rem;
    }
    
    /* Navigation */
    .nav-toggle {
        display: flex;
    }
    
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--bg-color);
        width: 100%;
        text-align: center;
        transition: left var(--transition-base);
        box-shadow: var(--shadow-md);
        padding: var(--spacing-lg) 0;
        gap: 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-item {
        width: 100%;
        padding: var(--spacing-sm) 0;
    }
    
    .nav-link {
        display: block;
        width: 100%;
        padding: var(--spacing-sm);
    }
    
    /* Hero */
    .hero {
        padding: var(--spacing-xl) 0;
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .hero-cta .btn {
        width: 100%;
    }
    
    /* Grids */
    .features-grid,
    .skills-grid,
    .case-studies-grid {
        grid-template-columns: 1fr;
    }
    
    /* Contact */
    .contact-wrapper {
        grid-template-columns: 1fr;
    }
    
    /* Footer */
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-social {
        justify-content: center;
    }
    
    /* Spacing */
    section {
        padding: var(--spacing-lg) 0;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .case-study-card,
    .contact-form-container,
    .contact-info {
        padding: var(--spacing-md);
    }
    
    .case-links {
        flex-direction: column;
    }
    
    .case-links .btn {
        width: 100%;
        text-align: center;
    }
    
    /* Hide caption on very small screens */
    .vis-caption {
        display: none;
    }
}

/* ============================================
   Print Styles
   ============================================ */

@media print {
    .navbar,
    .footer,
    .hero-cta,
    .case-links,
    .contact-form {
        display: none;
    }
    
    body {
        font-size: 12pt;
    }
    
    h1, h2, h3 {
        page-break-after: avoid;
    }
}