:root {
    --bg: #ffffff;
    --text: #1d1d1f;
    --text-secondary: #6e6e73;
    --accent: #0071e3;
    --accent-hover: #0077ed;
    --border: #d2d2d7;
    --surface: #f5f5f7;
    --card-bg: #ffffff;
    --code-bg: #1d1d1f;
    --code-text: #ffffff;
    --nav-bg: rgba(255, 255, 255, 0.8);
    --radius: 12px;
    --spacing: 80px;
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --bg: #000000;
        --text: #f5f5f7;
        --text-secondary: #a1a1a6;
        --accent: #2997ff;
        --accent-hover: #64b5f6;
        --border: #38383d;
        --surface: #1c1c1e;
        --card-bg: #2c2c2e;
        --code-bg: #1c1c1e;
        --code-text: #f5f5f7;
        --nav-bg: rgba(0, 0, 0, 0.8);
    }
}

[data-theme="dark"] {
    --bg: #000000;
    --text: #f5f5f7;
    --text-secondary: #a1a1a6;
    --accent: #2997ff;
    --accent-hover: #64b5f6;
    --border: #38383d;
    --surface: #1c1c1e;
    --card-bg: #2c2c2e;
    --code-bg: #1c1c1e;
    --code-text: #f5f5f7;
    --nav-bg: rgba(0, 0, 0, 0.8);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', system-ui, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 1120px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Navigation */
.nav {
    position: sticky;
    top: 0;
    background: var(--nav-bg);
    backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--border);
    z-index: 100;
}

.nav-content {
    max-width: 1120px;
    margin: 0 auto;
    padding: 0 24px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-weight: 600;
    font-size: 18px;
    letter-spacing: -0.02em;
}

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

.nav-links a {
    color: var(--text);
    text-decoration: none;
    font-size: 14px;
    transition: opacity 0.2s;
}

.nav-links a:hover {
    opacity: 0.7;
}

.nav-cta {
    background: var(--accent);
    color: white !important;
    padding: 6px 16px;
    border-radius: 20px;
}

.nav-cta:hover {
    background: var(--accent-hover);
    opacity: 1 !important;
}

/* Hero */
.hero {
    padding: 120px 0 var(--spacing);
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 24px;
}

.hero h1 {
    font-size: 64px;
    font-weight: 700;
    line-height: 1.1;
    letter-spacing: -0.03em;
    margin-bottom: 24px;
}

.hero-subtitle {
    font-size: 24px;
    color: var(--text-secondary);
    margin-bottom: 40px;
    line-height: 1.5;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 20px;
}

.btn {
    padding: 14px 32px;
    border-radius: 24px;
    text-decoration: none;
    font-size: 16px;
    font-weight: 500;
    transition: all 0.2s;
    display: inline-block;
}

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

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
}

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

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

.hero-footnote {
    font-size: 14px;
    color: var(--text-secondary);
}

/* Why Section */
.why {
    padding: var(--spacing) 0;
    background: var(--surface);
}

.why-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 48px;
}

.why-item {
    text-align: center;
}

.why-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.why-item h3 {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 12px;
    letter-spacing: -0.02em;
}

.why-item p {
    color: var(--text-secondary);
    font-size: 16px;
}

/* Features */
.features {
    padding: var(--spacing) 0;
}

.features h2 {
    font-size: 48px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 80px;
    letter-spacing: -0.03em;
}

.feature-block {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
    margin-bottom: 120px;
}

.feature-block-reverse {
    direction: rtl;
}

.feature-block-reverse > * {
    direction: ltr;
}

.feature-text h3 {
    font-size: 32px;
    font-weight: 600;
    margin-bottom: 24px;
    letter-spacing: -0.02em;
}

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

.feature-list li {
    padding: 12px 0;
    padding-left: 28px;
    position: relative;
    font-size: 17px;
    color: var(--text-secondary);
}

.feature-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--accent);
    font-weight: 600;
}

.feature-visual {
    background: var(--surface);
    border-radius: var(--radius);
    aspect-ratio: 16/10;
    display: flex;
    align-items: center;
    justify-content: center;
}

.placeholder {
    color: var(--text-secondary);
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* Feature Grid */
.feature-grid-section {
    padding: var(--spacing) 0;
    background: var(--surface);
}

.feature-grid-section h2 {
    font-size: 48px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 60px;
    letter-spacing: -0.03em;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 24px;
}

.feature-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 28px 24px;
    border: 1px solid var(--border);
    transition: transform 0.2s, box-shadow 0.2s;
}

.feature-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.feature-card-icon {
    font-size: 32px;
    margin-bottom: 12px;
}

.feature-card h4 {
    font-size: 17px;
    font-weight: 600;
    margin-bottom: 8px;
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
}

/* Technical */
.technical {
    padding: var(--spacing) 0;
    background: var(--surface);
}

.technical h2 {
    font-size: 48px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 60px;
    letter-spacing: -0.03em;
}

.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 40px;
}

.tech-item h4 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
}

.tech-item p {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.6;
}

/* Download */
.download {
    padding: var(--spacing) 0;
}

.download h2 {
    font-size: 48px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 60px;
    letter-spacing: -0.03em;
}

.download-option {
    margin-bottom: 48px;
}

.download-option h3 {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 16px;
}

.download-option pre {
    background: var(--code-bg);
    color: var(--code-text);
    padding: 24px;
    border-radius: var(--radius);
    overflow-x: auto;
    font-size: 14px;
    font-family: 'SF Mono', 'Monaco', 'Courier New', monospace;
    border: 1px solid var(--border);
}

.download-option p {
    font-size: 17px;
    color: var(--text-secondary);
}

.download-option a {
    color: var(--accent);
}

.download-note {
    text-align: center;
    color: var(--text-secondary);
    font-size: 14px;
    margin-top: 40px;
}

/* Shortcuts */
.shortcuts {
    padding: var(--spacing) 0;
    background: var(--surface);
}

.shortcuts h2 {
    font-size: 48px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 60px;
    letter-spacing: -0.03em;
}

.shortcuts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 24px;
    max-width: 900px;
    margin: 0 auto 32px;
}

.shortcut {
    background: var(--card-bg);
    padding: 24px;
    border-radius: var(--radius);
    text-align: center;
    border: 1px solid var(--border);
}

.shortcut-keys {
    font-size: 24px;
    font-weight: 600;
    display: block;
    margin-bottom: 8px;
    font-family: 'SF Mono', Monaco, monospace;
}

.shortcut-label {
    font-size: 14px;
    color: var(--text-secondary);
}

.shortcuts-note {
    text-align: center;
    color: var(--text-secondary);
    font-size: 14px;
}

.shortcuts-subheading {
    text-align: center;
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 24px;
    letter-spacing: -0.02em;
}

.shortcut-compact {
    padding: 16px;
}

.shortcut-compact .shortcut-keys {
    font-size: 20px;
    margin-bottom: 4px;
}

/* Support */
.support {
    padding: var(--spacing) 0;
    text-align: center;
}

.support h2 {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 24px;
    letter-spacing: -0.03em;
}

.support-intro {
    font-size: 20px;
    color: var(--text-secondary);
    margin-bottom: 40px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.support-options {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 24px;
}

.support-btn {
    padding: 14px 32px;
    border-radius: 24px;
    text-decoration: none;
    font-size: 16px;
    font-weight: 500;
    background: var(--accent);
    color: white;
    transition: all 0.2s;
    display: inline-block;
}

.support-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
}

.support-note {
    font-size: 14px;
    color: var(--text-secondary);
}

/* FAQ */
.faq {
    padding: var(--spacing) 0;
    background: var(--surface);
}

.faq h2 {
    font-size: 48px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 60px;
    letter-spacing: -0.03em;
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 40px;
}

.faq-item h4 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 12px;
}

.faq-item p {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.6;
}

/* Footer */
.footer {
    padding: 60px 0 40px;
    border-top: 1px solid var(--border);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 16px;
}

.footer-section p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
}

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

.footer-section ul li {
    margin-bottom: 8px;
}

.footer-section a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
}

.footer-section a:hover {
    color: var(--accent);
}

.footer-bottom {
    text-align: center;
    padding-top: 40px;
    border-top: 1px solid var(--border);
}

.footer-bottom p {
    font-size: 13px;
    color: var(--text-secondary);
}

/* Theme Toggle */
.theme-toggle {
    background: none;
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 4px 10px;
    cursor: pointer;
    font-size: 16px;
    line-height: 1;
    transition: border-color 0.2s;
    display: flex;
    align-items: center;
}

.theme-toggle:hover {
    border-color: var(--accent);
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 40px;
    }
    
    .hero-subtitle {
        font-size: 18px;
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .feature-block,
    .feature-block-reverse {
        grid-template-columns: 1fr;
        gap: 40px;
        direction: ltr;
    }
    
    .nav-links {
        gap: 20px;
    }
    
    .nav-links a {
        font-size: 13px;
    }
    
    .shortcuts-grid {
        grid-template-columns: 1fr;
    }
    
    .support-options {
        flex-direction: column;
    }
}