/* CSS Variables - Light Mode */
:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #0f172a;
    --accent-color: #06b6d4;
    --text-color: #334155;
    --text-light: #64748b;
    --bg-color: #ffffff;
    --bg-light: #f8fafc;
    --bg-dark: #0f172a;
    --border-color: #e2e8f0;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    --font-mono: 'SF Mono', 'Fira Code', 'Consolas', monospace;
    --max-width: 1200px;
    --header-height: 70px;
    --header-bg: rgba(255, 255, 255, 0.95);
    --card-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    --input-bg: #ffffff;
}

/* Dark Mode */
[data-theme="dark"] {
    --primary-color: #3b82f6;
    --primary-dark: #2563eb;
    --secondary-color: #f1f5f9;
    --accent-color: #22d3ee;
    --text-color: #e2e8f0;
    --text-light: #94a3b8;
    --bg-color: #0f172a;
    --bg-light: #1e293b;
    --bg-dark: #020617;
    --border-color: #334155;
    --header-bg: rgba(15, 23, 42, 0.95);
    --card-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    --input-bg: #1e293b;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    color: var(--text-color);
    background-color: var(--bg-color);
    line-height: 1.6;
}

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

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

/* Container */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: var(--header-bg);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-icon {
    width: 32px;
    height: 32px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 8px;
}

.nav {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links {
    display: flex;
    gap: 32px;
    list-style: none;
}

.nav-links a {
    color: var(--text-color);
    font-weight: 500;
    padding: 8px 0;
    position: relative;
}

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

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-color);
}

.nav-buttons {
    display: flex;
    gap: 12px;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 20px;
    font-size: 0.95rem;
    font-weight: 500;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
}

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

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

.btn-secondary {
    background: transparent;
    color: var(--text-color);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--bg-light);
    border-color: var(--text-light);
}

.btn-large {
    padding: 14px 28px;
    font-size: 1.05rem;
}

/* Hero Section */
.hero {
    padding: calc(var(--header-height) + 80px) 0 100px;
    background: linear-gradient(180deg, var(--bg-light) 0%, var(--bg-color) 100%);
}

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

.hero h1 {
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--secondary-color);
    margin-bottom: 24px;
    line-height: 1.1;
}

.hero .tagline {
    font-size: 1.25rem;
    color: var(--text-light);
    margin-bottom: 40px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 14px;
    background: rgba(37, 99, 235, 0.1);
    color: var(--primary-color);
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 24px;
}

/* Sections */
section {
    padding: 100px 0;
}

section:nth-child(even) {
    background: var(--bg-light);
}

.section-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 60px;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 16px;
}

.section-header p {
    font-size: 1.1rem;
    color: var(--text-light);
}

/* Features Grid */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 32px;
}

.feature-card {
    background: var(--bg-color);
    padding: 32px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.feature-card:hover {
    border-color: var(--primary-color);
    box-shadow: 0 4px 20px rgba(37, 99, 235, 0.1);
}

.feature-icon {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.1), rgba(6, 182, 212, 0.1));
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    font-size: 1.5rem;
}

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* Use Cases Section */
.use-cases {
    background: var(--bg-light);
}

.use-cases-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 32px;
}

.use-case-card {
    background: var(--bg-color);
    padding: 32px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease;
}

.use-case-card:hover {
    border-color: var(--primary-color);
    box-shadow: 0 4px 20px rgba(37, 99, 235, 0.1);
}

.use-case-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.1), rgba(6, 182, 212, 0.1));
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    font-size: 1.75rem;
}

.use-case-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 12px;
}

.use-case-card > p {
    color: var(--text-light);
    font-size: 0.95rem;
    margin-bottom: 20px;
    line-height: 1.6;
}

.use-case-benefits {
    list-style: none;
    padding: 0;
    margin: 0;
}

.use-case-benefits li {
    position: relative;
    padding-left: 24px;
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: var(--text-color);
}

.use-case-benefits li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: 600;
}

/* Technology Section */
.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 24px;
}

.tech-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    padding: 20px;
    background: var(--bg-color);
    border-radius: 10px;
    border: 1px solid var(--border-color);
}

.tech-icon {
    width: 40px;
    height: 40px;
    background: var(--bg-light);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 1.25rem;
}

.tech-item h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 4px;
}

.tech-item p {
    font-size: 0.875rem;
    color: var(--text-light);
}

/* Pricing Section */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 32px;
    max-width: 900px;
    margin: 0 auto;
}

.pricing-card {
    background: var(--bg-color);
    border-radius: 16px;
    border: 1px solid var(--border-color);
    padding: 40px;
    position: relative;
    transition: all 0.2s ease;
}

.pricing-card:hover {
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
}

.pricing-card.featured {
    border-color: var(--primary-color);
    box-shadow: 0 8px 30px rgba(37, 99, 235, 0.15);
}

.pricing-card.featured::before {
    content: 'Recommended';
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--primary-color);
    color: white;
    padding: 4px 16px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
}

.pricing-tier {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--primary-color);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 8px;
}

.pricing-card h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 16px;
}

.pricing-price {
    margin-bottom: 24px;
}

.pricing-price .amount {
    font-size: 3rem;
    font-weight: 800;
    color: var(--secondary-color);
}

.pricing-price .period {
    font-size: 1rem;
    color: var(--text-light);
}

.pricing-price .tax-note {
    font-size: 0.8rem;
    color: var(--text-light);
    margin-top: 4px;
}

.pricing-description {
    color: var(--text-light);
    margin-bottom: 24px;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--border-color);
}

.pricing-features {
    list-style: none;
    margin-bottom: 32px;
}

.pricing-features li {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 8px 0;
    color: var(--text-color);
    font-size: 0.95rem;
}

.pricing-features li::before {
    content: '✓';
    color: var(--success-color);
    font-weight: 600;
    flex-shrink: 0;
}

.pricing-features li.disabled {
    color: var(--text-light);
}

.pricing-features li.disabled::before {
    content: '—';
    color: var(--text-light);
}

.pricing-card .btn {
    width: 100%;
}

/* CTA Section */
.cta-section {
    background: var(--bg-dark);
    color: white;
    text-align: center;
}

.cta-section h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.cta-section p {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 32px;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.cta-section .btn-primary {
    background: white;
    color: #0f172a;
}

.cta-section .btn-primary:hover {
    background: #f1f5f9;
    color: #0f172a;
}

/* Footer */
.footer {
    background: var(--bg-dark);
    color: rgba(255, 255, 255, 0.7);
    padding: 60px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr repeat(3, 1fr);
    gap: 48px;
    margin-bottom: 48px;
}

.footer-brand .logo {
    color: white;
    margin-bottom: 16px;
}

.footer-brand p {
    font-size: 0.95rem;
    max-width: 280px;
}

.footer-column h4 {
    color: white;
    font-size: 0.9rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 20px;
}

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

.footer-column li {
    margin-bottom: 12px;
}

.footer-column a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.95rem;
}

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

.footer-bottom {
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
}

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

.footer-social {
    display: flex;
    gap: 16px;
}

.footer-social a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 1.25rem;
}

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

/* Login Page */
.login-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    background: var(--bg-light);
}

.login-card {
    background: var(--bg-color);
    padding: 48px;
    border-radius: 16px;
    box-shadow: var(--card-shadow);
    width: 100%;
    max-width: 420px;
    text-align: center;
}

.login-card .logo {
    justify-content: center;
    margin-bottom: 32px;
}

.login-card h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 8px;
}

.login-card .subtitle {
    color: var(--text-light);
    margin-bottom: 32px;
}

.form-group {
    margin-bottom: 20px;
    text-align: left;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-color);
    margin-bottom: 8px;
}

.form-group input {
    width: 100%;
    padding: 12px 16px;
    font-size: 1rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    transition: all 0.2s ease;
    background: var(--input-bg);
    color: var(--text-color);
}

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

.login-card .btn {
    width: 100%;
    margin-top: 8px;
}

.login-footer {
    margin-top: 24px;
    font-size: 0.875rem;
    color: var(--text-light);
}

/* Code Block */
.code-block {
    background: var(--bg-dark);
    border-radius: 8px;
    padding: 20px;
    overflow-x: auto;
    margin: 24px 0;
}

.code-block code {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: #e2e8f0;
    line-height: 1.6;
}

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

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

    .section-header h2 {
        font-size: 2rem;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }

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

/* Theme Toggle */
.theme-toggle {
    background: none;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 8px 12px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    transition: all 0.2s ease;
}

.theme-toggle:hover {
    background: var(--bg-light);
    border-color: var(--text-light);
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
    stroke: currentColor;
}

/* Light mode: show sun, hide moon */
.theme-toggle .icon-moon {
    display: none;
}

/* Dark mode: show moon, hide sun */
[data-theme="dark"] .theme-toggle .icon-sun {
    display: none;
}

[data-theme="dark"] .theme-toggle .icon-moon {
    display: block;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mt-4 {
    margin-top: 1rem;
}

.mb-4 {
    margin-bottom: 1rem;
}