/* CSS Variables */
:root {
    --primary: #667eea;
    --primary-dark: #5a67d8;
    --secondary: #764ba2;
    --accent: #38ef7d;
    --dark: #1a202c;
    --gray-900: #1a202c;
    --gray-800: #2d3748;
    --gray-700: #4a5568;
    --gray-600: #718096;
    --gray-500: #a0aec0;
    --gray-400: #cbd5e0;
    --gray-300: #e2e8f0;
    --gray-200: #edf2f7;
    --gray-100: #f7fafc;
    --white: #ffffff;
    --gradient: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    --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: 16px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--gray-800);
    background-color: var(--white);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--gray-900);
}

h1 { font-size: 3rem; }
h2 { font-size: 2.25rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p { margin-bottom: 1rem; }

a {
    color: var(--primary);
    text-decoration: none;
    transition: color 0.2s ease;
}

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

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 500;
    text-align: center;
    border-radius: var(--radius);
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
}

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

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

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

.btn-secondary:hover {
    background: var(--gray-100);
    color: var(--primary);
}

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--white);
    box-shadow: var(--shadow);
    z-index: 1000;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 72px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-menu a {
    color: var(--gray-700);
    font-weight: 500;
    transition: color 0.2s ease;
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.nav-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background: var(--gray-700);
    border-radius: 2px;
    transition: all 0.3s ease;
}

/* Hero Section */
.hero {
    padding: 10rem 0 6rem;
    background: var(--gradient);
    color: var(--white);
    text-align: center;
}

.hero h1 {
    color: var(--white);
    margin-bottom: 1rem;
    font-size: 3.5rem;
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

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

.hero .btn-primary:hover {
    background: var(--gray-100);
    color: var(--primary);
}

.hero .btn-secondary {
    border-color: var(--white);
    color: var(--white);
    background: transparent;
}

.hero .btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--white);
}

/* Features Section */
.features {
    padding: 6rem 0;
    background: var(--gray-100);
}

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

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

.feature-card {
    background: var(--white);
    padding: 2rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
    text-align: center;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

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

.feature-icon {
    color: var(--primary);
    margin-bottom: 1rem;
}

.feature-card h3 {
    margin-bottom: 0.75rem;
}

.feature-card p {
    color: var(--gray-600);
    margin-bottom: 0;
}

/* CTA Section */
.cta-section {
    padding: 6rem 0;
    background: var(--gray-900);
    color: var(--white);
    text-align: center;
}

.cta-section h2 {
    color: var(--white);
    margin-bottom: 1rem;
}

.cta-section p {
    color: var(--gray-400);
    margin-bottom: 2rem;
    font-size: 1.125rem;
}

/* Content Section */
.content-section {
    padding: 6rem 0;
}

.content-section.alt {
    background: var(--gray-100);
}

.content-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.content-card {
    background: var(--white);
    padding: 2rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
}

.content-card h3 {
    margin-bottom: 1rem;
}

.content-card p {
    color: var(--gray-600);
}

/* Page Header */
.page-header {
    padding: 8rem 0 4rem;
    background: var(--gradient);
    color: var(--white);
    text-align: center;
}

.page-header h1 {
    color: var(--white);
}

.page-header p {
    opacity: 0.9;
    max-width: 600px;
    margin: 1rem auto 0;
}

/* Contact Form */
.contact-form {
    max-width: 600px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--gray-700);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 2px solid var(--gray-300);
    border-radius: var(--radius);
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.2s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

/* Footer */
.footer {
    background: var(--gray-900);
    color: var(--gray-400);
    padding: 4rem 0 2rem;
}

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

.footer-brand .logo {
    margin-bottom: 1rem;
    display: inline-block;
}

.footer-brand p {
    color: var(--gray-500);
}

.footer-links h4,
.footer-contact h4 {
    color: var(--white);
    margin-bottom: 1rem;
}

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

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

.footer-links a {
    color: var(--gray-500);
}

.footer-links a:hover {
    color: var(--white);
}

.footer-contact p {
    color: var(--gray-500);
}

.footer-bottom {
    border-top: 1px solid var(--gray-800);
    padding-top: 2rem;
    text-align: center;
}

.footer-bottom p {
    margin: 0;
    color: var(--gray-600);
}

/* Responsive */
@media (max-width: 768px) {
    h1 { font-size: 2.25rem; }
    h2 { font-size: 1.75rem; }

    .hero h1 {
        font-size: 2.5rem;
    }

    .nav-menu {
        position: fixed;
        top: 72px;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 2rem;
        gap: 1rem;
        box-shadow: var(--shadow-lg);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .nav-toggle {
        display: flex;
    }

    .hero-cta {
        flex-direction: column;
        align-items: center;
    }

    .hero-cta .btn {
        width: 100%;
        max-width: 280px;
    }
}

/* Error Page */
.error-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 2rem;
}

.error-page h1 {
    font-size: 8rem;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 1rem;
}

.error-page p {
    color: var(--gray-600);
    margin-bottom: 2rem;
}