/* CSS Variables */
:root {
    --bg: #0C0F10;
    --surface: #121518;
    --text: #EDEFF1;
    --muted: #AAB3BD;
    --accent: #38F3A6;
    --accent-2: #D9C07A;
    
    /* Typography */
    --font-heading: 'Space Grotesk', system-ui, sans-serif;
    --font-body: 'Inter', system-ui, sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 2rem;
    --spacing-lg: 3rem;
    --spacing-xl: 4rem;
    --spacing-2xl: 6rem;
    
    /* Layout */
    --max-width: 920px;
    --border-radius: 0.5rem;
    
    /* Animation */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Light theme variables (for theme toggle) */
[data-theme="light"] {
    --bg: #F7F5EB;
    --surface: #FFFFFF;
    --text: #1B1F23;
    --muted: #4A5568;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-body);
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.7;
    font-weight: 400;
    overflow-x: hidden;
}

/* Skip to content link */
.skip-link {
    position: absolute;
    top: -40px;
    left: 6px;
    background: var(--accent);
    color: var(--bg);
    padding: 8px;
    text-decoration: none;
    border-radius: var(--border-radius);
    z-index: 1000;
    transition: var(--transition);
}

.skip-link:focus {
    top: 6px;
}

/* Typography */
h1, h2, h3 {
    font-family: var(--font-heading);
    font-weight: 600;
    letter-spacing: -0.025em;
    line-height: 1.2;
}

h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 700;
}

h2 {
    font-size: clamp(2rem, 4vw, 3rem);
}

h3 {
    font-size: clamp(1.5rem, 3vw, 2rem);
}

p {
    font-size: 1.125rem;
    line-height: 1.7;
}

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

.section {
    padding: var(--spacing-2xl) 0;
    opacity: 0;
    transform: translateY(2rem);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
    position: relative;
}

.section:not(.hero):not(:last-child)::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60%;
    height: 1px;
    background: linear-gradient(90deg, transparent 0%, rgba(56, 243, 166, 0.2) 20%, rgba(217, 192, 122, 0.1) 80%, transparent 100%);
}

.section.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Keyframe Animations */
@keyframes heroGradientShift {
    0% {
        background: linear-gradient(135deg, var(--bg) 0%, var(--surface) 100%);
    }
    50% {
        background: linear-gradient(135deg, #0A0E0F 0%, #16252A 100%);
    }
    100% {
        background: linear-gradient(135deg, var(--bg) 0%, var(--surface) 100%);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(2rem);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes glowPulse {
    0%, 100% {
        box-shadow: 0 0 5px rgba(56, 243, 166, 0.2);
    }
    50% {
        box-shadow: 0 0 20px rgba(56, 243, 166, 0.4);
    }
}

/* Respect reduced motion */
@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
    
    .section {
        opacity: 1;
        transform: none;
        transition: none;
    }
    
    .hero {
        animation: none !important;
    }
    
    .hero-content.fade-in {
        animation: none !important;
    }
    
    .approach-list li {
        opacity: 1 !important;
        transform: none !important;
        transition: none !important;
    }
    
    .btn-primary,
    .nav-link,
    .nav-cta {
        transition: none !important;
    }
}

/* Navigation */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(12, 15, 16, 0.95);
    backdrop-filter: blur(10px);
    z-index: 100;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid rgba(237, 239, 241, 0.1);
}

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

.nav-logo {
    font-family: var(--font-heading);
    font-weight: 600;
    font-size: 1.25rem;
    color: var(--text);
    text-decoration: none;
    letter-spacing: -0.02em;
}

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

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

.nav-link:hover,
.nav-link:focus {
    color: var(--accent);
    text-shadow: 0 0 8px rgba(56, 243, 166, 0.4);
    outline: none;
    transition: var(--transition-fast);
}

.nav-link:focus {
    text-shadow: 0 0 0 2px var(--accent);
}

.nav-cta {
    background: var(--accent);
    color: var(--bg);
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    border: none;
    cursor: pointer;
}

.nav-cta:hover,
.nav-cta:focus {
    transform: scale(1.05);
    box-shadow: 0 0 20px rgba(56, 243, 166, 0.4);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    background: linear-gradient(135deg, var(--bg) 0%, var(--surface) 100%);
    animation: heroGradientShift 12s ease-in-out infinite;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(ellipse at 70% 20%, rgba(56, 243, 166, 0.1) 0%, transparent 50%),
                radial-gradient(ellipse at 20% 80%, rgba(217, 192, 122, 0.05) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
}

.hero-content.fade-in {
    animation: fadeInUp 0.8s ease-out;
}

.hero h1 {
    margin-bottom: var(--spacing-md);
    background: linear-gradient(135deg, var(--text) 0%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--muted);
    margin-bottom: var(--spacing-xl);
    font-weight: 400;
}

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

.btn-primary {
    background: var(--accent);
    color: var(--bg);
    padding: 1rem 2rem;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-size: 1.125rem;
}

.btn-primary:hover,
.btn-primary:focus {
    background: var(--accent);
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 15px 35px rgba(56, 243, 166, 0.4), 0 0 15px rgba(56, 243, 166, 0.3);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
    transition: var(--transition-fast);
}

.btn-secondary {
    color: var(--muted);
    text-decoration: none;
    font-weight: 500;
    padding: 1rem 0;
    position: relative;
    transition: var(--transition);
}

.btn-secondary:hover,
.btn-secondary:focus {
    color: var(--accent);
    outline: none;
}

.btn-secondary::after {
    content: '→';
    margin-left: 0.5rem;
    transition: var(--transition);
}

.btn-secondary:hover::after {
    transform: translateX(0.25rem);
}

/* Services Section */
.services-interactive {
    display: flex;
    align-items: stretch;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
    position: relative;
    min-height: 300px;
}

.services-nav {
    background: var(--surface);
    border: 1px solid rgba(237, 239, 241, 0.1);
    border-radius: 50%;
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--muted);
    cursor: pointer;
    transition: var(--transition);
    flex-shrink: 0;
    z-index: 2;
    align-self: center;
}

.services-nav:hover {
    background: var(--accent);
    color: var(--bg);
    border-color: var(--accent);
    transform: scale(1.1);
}

.services-nav:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.services-nav:disabled:hover {
    background: var(--surface);
    color: var(--muted);
    border-color: rgba(237, 239, 241, 0.1);
}

.services-container {
    display: flex;
    gap: var(--spacing-sm);
    flex: 1;
    align-items: center;
    justify-content: center;
}

.service-card {
    background: var(--surface);
    border-radius: var(--border-radius);
    border: 1px solid rgba(237, 239, 241, 0.1);
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    position: relative;
    overflow: hidden;
}

/* Inactive cards - smaller and more subtle */
.service-card:not(.active) {
    width: 180px;
    height: 120px;
    opacity: 0.7;
    transform: scale(0.9);
    background: rgba(18, 21, 24, 0.6);
    overflow: hidden;
}

.service-card:not(.active):hover {
    opacity: 0.9;
    transform: scale(0.95);
    border-color: rgba(56, 243, 166, 0.2);
}

.service-card:not(.active) h3 {
    color: var(--muted);
    font-size: 1.1rem;
    padding: var(--spacing-lg);
    margin: 0;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    transition: var(--transition);
}

/* Ensure inactive cards hide content completely */
.service-card:not(.active) .service-content {
    display: none;
}

/* Active card - prominent and expanded */
.service-card.active {
    width: 420px;
    min-height: 280px;
    height: auto;
    padding: var(--spacing-xl);
    border-color: rgba(56, 243, 166, 0.4);
    box-shadow: 0 20px 60px rgba(56, 243, 166, 0.15);
    transform: scale(1.02);
    z-index: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: var(--spacing-lg);
}

.service-card.active h3 {
    color: var(--accent);
    font-size: 1.75rem;
    padding: 0;
    margin: 0;
    text-align: left;
    font-weight: 600;
    transition: var(--transition);
    flex-shrink: 0;
}

.service-content {
    padding: 0;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    max-height: 0;
    overflow: hidden;
}

.service-card.active .service-content {
    opacity: 1;
    transform: translateY(0);
    max-height: none;
    transition-delay: 0.2s;
}

.service-card p {
    color: var(--muted);
    font-size: 1.1rem;
    line-height: 1.7;
    margin: 0;
}

/* Approach Section */
.approach-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--spacing-xl);
    align-items: start;
    margin-top: var(--spacing-xl);
}

.approach-intro {
    font-size: 1.25rem;
    color: var(--text);
    font-weight: 500;
}

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

.approach-list li {
    padding: var(--spacing-sm) 0;
    color: var(--muted);
    position: relative;
    padding-left: 2rem;
    opacity: 0;
    transform: translateX(-1rem);
    transition: opacity 0.4s ease-out, transform 0.4s ease-out;
}

.approach-list li.animate {
    opacity: 1;
    transform: translateX(0);
}

.approach-list li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: 600;
}

/* Experience Section */
.experience-content {
    max-width: 700px;
    margin: var(--spacing-xl) auto 0;
    text-align: center;
}

.experience-content p {
    font-size: 1.25rem;
    color: var(--muted);
    line-height: 1.8;
}

/* Contact Section */
.contact-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.contact h2 {
    margin-bottom: var(--spacing-sm);
}

.contact-subtitle {
    color: var(--muted);
    margin-bottom: var(--spacing-xl);
    font-size: 1.125rem;
}

.contact-form {
    background: var(--surface);
    padding: var(--spacing-xl);
    border-radius: var(--border-radius);
    border: 1px solid rgba(237, 239, 241, 0.1);
    margin-bottom: var(--spacing-lg);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.form-group {
    margin-bottom: var(--spacing-md);
}

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

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    background: var(--bg);
    border: 1px solid rgba(237, 239, 241, 0.2);
    border-radius: var(--border-radius);
    color: var(--text);
    font-family: var(--font-body);
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(56, 243, 166, 0.2);
}

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

.form-error {
    color: #ef4444;
    font-size: 0.875rem;
    margin-top: var(--spacing-xs);
    display: none;
}

.form-group.error input,
.form-group.error textarea {
    border-color: #ef4444;
}

.form-group.error .form-error {
    display: block;
}

.contact-email {
    color: var(--accent);
    text-decoration: none;
    font-weight: 600;
    font-size: 1.125rem;
    margin-bottom: var(--spacing-md);
    display: inline-block;
}

.contact-email:hover,
.contact-email:focus {
    text-shadow: 0 0 10px rgba(56, 243, 166, 0.5);
    outline: none;
}

.privacy-note {
    color: var(--muted);
    font-size: 0.875rem;
    margin-top: var(--spacing-md);
    font-style: italic;
}

/* Success/Error Messages */
.message {
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    margin-bottom: var(--spacing-md);
}

.message:not(.show) {
    display: none;
}

.message.show {
    display: block !important;
    z-index: 1000;
    position: relative;
}

.message.success {
    background: rgba(34, 197, 94, 0.1);
    border: 1px solid rgba(34, 197, 94, 0.3);
    color: #22c55e;
}

.message.error {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #ef4444;
}

/* Footer */
.footer {
    background: var(--surface);
    padding: var(--spacing-lg) 0;
    text-align: center;
    border-top: 1px solid rgba(237, 239, 241, 0.1);
}

.footer-content {
    color: var(--muted);
    font-size: 0.875rem;
}

.footer-links {
    display: inline-flex;
    gap: 1rem;
    margin-left: 1rem;
}

.footer-link {
    color: var(--muted);
    text-decoration: none;
    transition: var(--transition);
}

.footer-link:hover,
.footer-link:focus {
    color: var(--accent);
    outline: none;
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: var(--accent);
    color: var(--bg);
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    opacity: 0;
    transform: translateY(1rem);
    transition: var(--transition);
    z-index: 50;
}

.back-to-top.visible {
    opacity: 1;
    transform: translateY(0);
}

.back-to-top:hover,
.back-to-top:focus {
    transform: translateY(-2px) scale(1.1);
    box-shadow: 0 5px 15px rgba(56, 243, 166, 0.4);
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* Theme Toggle */
.theme-toggle {
    background: none;
    border: 1px solid rgba(237, 239, 241, 0.2);
    color: var(--muted);
    padding: 0.5rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-size: 1.25rem;
}

.theme-toggle:hover,
.theme-toggle:focus {
    color: var(--accent);
    border-color: var(--accent);
    outline: none;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-links {
        gap: var(--spacing-md);
    }
    
    .nav-link {
        display: none;
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .services-interactive {
        flex-direction: column;
        gap: var(--spacing-md);
        min-height: auto;
    }
    
    .services-container {
        flex-direction: column;
        gap: var(--spacing-md);
        align-items: stretch;
    }
    
    .service-card:not(.active) {
        width: 100%;
        height: 80px;
        transform: scale(1);
        opacity: 0.8;
    }
    
    .service-card.active {
        width: 100%;
        height: auto;
        min-height: 200px;
        transform: scale(1);
    }
    
    .service-card.active h3 {
        text-align: center;
        font-size: 1.5rem;
        padding: var(--spacing-lg) var(--spacing-lg) var(--spacing-sm);
    }
    
    .service-content {
        padding: 0 var(--spacing-lg) var(--spacing-lg);
    }
    
    .services-nav {
        align-self: center;
    }
    
    .approach-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .footer-links {
        display: block;
        margin: var(--spacing-sm) 0;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .section {
        padding: var(--spacing-xl) 0;
    }
    
    .contact-form {
        padding: var(--spacing-lg);
    }
}

/* Section Headers */
.section-header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.section-intro {
    color: var(--muted);
    font-size: 1.125rem;
    margin-top: var(--spacing-sm);
}