:root {
    --primary: #2563eb;
    --primary-dark: #1e40af;
    --secondary: #10b981;
    --accent: #8b5cf6;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-light);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Header */
header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    padding: 2rem 0;
    text-align: center;
    box-shadow: var(--shadow-lg);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.logo-section {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 0.5rem;
}

.logo {
    width: 48px;
    height: 48px;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.tagline {
    font-size: 0.95rem;
    opacity: 0.95;
    margin-bottom: 1.5rem;
}

.header-nav {
    display: flex;
    gap: 2rem;
    justify-content: center;
    flex-wrap: wrap;
}

.header-nav a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.2s;
    font-size: 0.95rem;
}

.header-nav a:hover {
    opacity: 0.8;
}

/* Hero Section */
.hero-section {
    text-align: center;
    padding: 4rem 0 3rem;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Stats Section */
.stats-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin: 3rem 0;
}

.stat-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
}

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

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 0.5rem;
}

.stat-label {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Featured Section */
.featured-section {
    margin: 4rem 0;
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-header h2 {
    font-size: 2rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.section-description {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

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

.featured-card {
    background: white;
    border-radius: 16px;
    padding: 2.5rem;
    box-shadow: var(--shadow-lg);
    transition: transform 0.3s, box-shadow 0.3s;
    position: relative;
    overflow: hidden;
}

.featured-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
}

.gradient-quicksell::before {
    background: linear-gradient(90deg, #f59e0b, #ef4444);
}

.gradient-coinbot::before {
    background: linear-gradient(90deg, #8b5cf6, #3b82f6);
}

.featured-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-xl);
}

.featured-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.featured-card h3 {
    font-size: 1.5rem;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.featured-description {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.featured-features {
    list-style: none;
    margin: 1.5rem 0;
    padding: 0;
}

.featured-features li {
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
    padding-left: 0;
    font-size: 0.95rem;
}

.featured-btn {
    display: inline-block;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: transform 0.2s, box-shadow 0.2s;
    margin-top: 1rem;
}

.featured-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgb(37 99 235 / 0.4);
}

/* About Section */
.about-section {
    background: white;
    padding: 3rem;
    border-radius: 16px;
    margin: 4rem 0;
    box-shadow: var(--shadow);
}

.about-section h2 {
    font-size: 1.75rem;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}

.about-section p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.7;
}

/* Platforms Section */
.platforms-section {
    margin: 4rem 0;
}

.platform-category {
    background: white;
    border-radius: 12px;
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
}

.category-title {
    font-size: 1.25rem;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    padding-bottom: 0.75rem;
    border-bottom: 2px solid var(--border);
}

.platform-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1rem;
}

.platform-item {
    padding: 0.5rem 0;
}

.platform-link {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    padding: 1rem;
    border-radius: 8px;
    text-decoration: none;
    color: var(--text-primary);
    transition: background-color 0.2s, transform 0.2s;
}

.platform-link:hover {
    background-color: var(--bg-light);
    transform: translateX(4px);
}

.platform-link strong {
    color: var(--primary);
    font-size: 1rem;
}

.platform-desc {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.platform-summary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    padding: 1.5rem;
    border-radius: 12px;
    text-align: center;
    margin-top: 2rem;
}

.platform-summary p {
    margin: 0;
    font-size: 1.1rem;
}

/* Contact Section */
.contact-section {
    background: white;
    padding: 3rem;
    border-radius: 16px;
    margin: 4rem 0;
    box-shadow: var(--shadow-lg);
}

.contact-section h2 {
    font-size: 1.75rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.contact-section > p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.contact-form {
    max-width: 600px;
    margin: 0 auto;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 1rem;
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-family: inherit;
    font-size: 0.95rem;
    transition: border-color 0.2s, box-shadow 0.2s;
}

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

.submit-btn {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    padding: 0.875rem 2rem;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    margin-top: 1rem;
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgb(37 99 235 / 0.4);
}

.form-message {
    margin-top: 1rem;
    padding: 0.75rem;
    border-radius: 8px;
    display: none;
}

.form-message.success {
    background: #d1fae5;
    color: #065f46;
    display: block;
}

.form-message.error {
    background: #fee2e2;
    color: #991b1b;
    display: block;
}

.g-recaptcha {
    margin-top: 1rem;
}

/* Tech Stack */
.tech-stack {
    text-align: center;
    margin: 4rem 0;
    padding: 3rem;
    background: white;
    border-radius: 16px;
    box-shadow: var(--shadow);
}

.tech-stack h2 {
    font-size: 1.75rem;
    margin-bottom: 0.5rem;
}

.section-subtitle {
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.tech-list {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
    max-width: 800px;
    margin: 0 auto;
}

.tech-badge {
    background: linear-gradient(135deg, var(--bg-light), white);
    border: 1px solid var(--border);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
    transition: transform 0.2s, border-color 0.2s;
}

.tech-badge:hover {
    transform: translateY(-2px);
    border-color: var(--primary);
}

/* Footer */
footer {
    background: linear-gradient(135deg, #1f2937, #111827);
    color: white;
    padding: 3rem 0 1.5rem;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.footer-section p {
    color: #d1d5db;
    font-size: 0.9rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: #d1d5db;
    text-decoration: none;
    transition: color 0.2s;
    font-size: 0.9rem;
}

.footer-section a:hover {
    color: white;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #374151;
    color: #9ca3af;
}

.footer-bottom p {
    margin: 0.25rem 0;
    font-size: 0.875rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 1rem;
    }

    header h1 {
        font-size: 2rem;
    }

    .hero-title {
        font-size: 1.75rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .stats-section {
        grid-template-columns: 1fr 1fr;
    }

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

    .form-row {
        grid-template-columns: 1fr;
    }

    .platform-list {
        grid-template-columns: 1fr;
    }

    .header-nav {
        gap: 1rem;
        font-size: 0.875rem;
    }

    .about-section,
    .contact-section,
    .tech-stack {
        padding: 2rem 1.5rem;
    }

    .platform-category {
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    .stats-section {
        grid-template-columns: 1fr;
    }

    .hero-title {
        font-size: 1.5rem;
    }

    .stat-number {
        font-size: 2rem;
    }
}

/* Smooth Animations */
@media (prefers-reduced-motion: no-preference) {
    * {
        scroll-behavior: smooth;
    }

    .stat-card,
    .featured-card,
    .platform-link,
    .tech-badge {
        animation: fadeInUp 0.6s ease-out;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}