:root {
    --nav-bg: rgba(0, 0, 0, 0.98);
    --bg: #000000;
    --fg: #fafafa;
    --muted: #9a9a9a;
    --light: #1a1a1a;
    --accent: #ff3d00;
    --accent-dim: #ff3d0030;
    color-scheme: dark;
}

[data-theme="light"] {
    --nav-bg: rgba(250, 250, 250, 0.95);
    --bg: #fafafa;
    --fg: #0a0a0a;
    --muted: #666;
    --light: #e5e5e5;
    --accent: #ff3d00;
    --accent-dim: #ff3d0020;
    color-scheme: light;
}

body,
nav {
    transition: background-color 0.28s ease, color 0.28s ease, border-color 0.28s ease;
}

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

body {
    font-family: 'Inter', sans-serif;
    background: var(--bg);
    color: var(--fg);
    line-height: 1.6;
    font-size: 15px;
    overflow-x: hidden;
}

::selection { background: var(--accent); color: white; }

nav {
    position: fixed;
    top: 0; left: 0; width: 100%;
    padding: 1.5rem 3rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
    background: var(--nav-bg);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--light);
}

.logo {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--fg);
    text-decoration: none;
    letter-spacing: 0;
}

.logo::before {
    content: '// ';
    color: var(--accent);
}

.checkout-section {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 8rem 5% 4rem;
    text-align: center;
    position: relative;
}

.hero-grid {
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    background-image:
        linear-gradient(var(--light) 1px, transparent 1px),
        linear-gradient(90deg, var(--light) 1px, transparent 1px);
    background-size: 80px 80px;
    opacity: 0.3; pointer-events: none;
}

.checkout-content {
    position: relative;
    z-index: 10;
    max-width: 600px;
}

.section-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.75rem;
    color: var(--accent);
    letter-spacing: 2px;
    margin-bottom: 2rem;
    display: block;
}

.checkout-title {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: 0;
    margin-bottom: 1rem;
}

.checkout-subtitle {
    color: var(--muted);
    font-size: 1.1rem;
    line-height: 1.7;
    margin-bottom: 3rem;
}

.gumroad-cta {
    display: inline-flex;
    align-items: center;
    gap: 1rem;
    padding: 1.4rem 3rem;
    background: var(--accent);
    color: white;
    text-decoration: none;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 1px;
    transition: all 0.2s;
    border: none;
    cursor: pointer;
}

.gumroad-cta:hover {
    background: #e63600;
    transform: translateY(-2px);
    box-shadow: 0 10px 20px var(--accent-dim);
}

.gumroad-cta.is-hidden {
    display: none;
}

.back-link {
    display: inline-block;
    margin-top: 2rem;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.8rem;
    color: var(--muted);
    text-decoration: none;
    transition: color 0.2s;
}

.back-link:hover {
    color: var(--accent);
}

.redirect-note {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.75rem;
    color: var(--muted);
    margin-top: 1rem;
    display: none;
}

.redirect-note.active { display: block; }

footer {
    padding: 4rem 5% 2rem;
    border-top: 1px solid var(--light);
    background: var(--bg);
    position: relative;
    z-index: 10;
}

.footer-bottom {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.75rem;
    color: var(--muted);
    padding-top: 2rem;
}

@media (max-width: 600px) {
    nav { padding: 1rem 1.5rem; }
    .checkout-title { font-size: 1.8rem; }
    .footer-bottom {
        flex-direction: column;
        gap: 1rem;
        align-items: center;
    }
}