:root {
    --bg: #0e0e10;
    --bg-secondary: #18181b;
    --text: #e4e4e7;
    --text-secondary: #a1a1aa;
    --accent: #6d5dfc;
    --accent-hover: #8577fd;
    --border: #27272a;
    --radius: 8px;
}

@media (prefers-color-scheme: light) {
    :root {
        --bg: #ffffff;
        --bg-secondary: #f4f4f5;
        --text: #18181b;
        --text-secondary: #71717a;
        --border: #e4e4e7;
    }
}

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

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

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-hover); }

img { max-width: 100%; display: block; }

/* Layout */
.container { max-width: 1120px; margin: 0 auto; padding: 0 1.5rem; }
.row { display: flex; flex-wrap: wrap; gap: 2rem; }
.row > * { flex: 1; min-width: 0; }

.py-5 { padding-top: 4rem; padding-bottom: 4rem; }
.py-4 { padding-top: 2.5rem; padding-bottom: 2.5rem; }
.mb-3 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 1.5rem; }
.mb-5 { margin-bottom: 2.5rem; }
.mt-4 { margin-top: 1.5rem; }
.mt-5 { margin-top: 2.5rem; }
.text-center { text-align: center; }
.text-secondary { color: var(--text-secondary); }

/* Typography */
h1 { font-size: 2.75rem; font-weight: 700; line-height: 1.15; letter-spacing: -0.02em; }
h2 { font-size: 2rem; font-weight: 700; letter-spacing: -0.01em; }
h3, h4 { font-size: 1.25rem; font-weight: 600; }
p { color: var(--text-secondary); }
.lead { font-size: 1.15rem; }

/* Navbar */
.navbar-top { border-bottom: 1px solid var(--border); }
.navbar-top .container { display: flex; align-items: center; justify-content: space-between; height: 4rem; }
.navbar-brand { font-weight: 700; font-size: 1.2rem; color: var(--text); }
.navbar-nav { display: flex; list-style: none; gap: 1.5rem; align-items: center; }
.navbar-nav a { color: var(--text-secondary); font-size: 0.9rem; transition: color 0.15s; }
.navbar-nav a:hover, .navbar-nav a.active { color: var(--text); }

/* Buttons */
.btn-primary {
    display: inline-block;
    background: var(--accent);
    color: #fff;
    padding: 0.7rem 1.6rem;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.95rem;
    border: none;
    cursor: pointer;
    transition: background 0.15s;
}
.btn-primary:hover { background: var(--accent-hover); color: #fff; }

.btn-secondary {
    display: inline-block;
    background: transparent;
    color: var(--text);
    padding: 0.7rem 1.6rem;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.95rem;
    border: 1px solid var(--border);
    cursor: pointer;
    transition: border-color 0.15s;
}
.btn-secondary:hover { border-color: var(--text-secondary); color: var(--text); }

/* Sections */
section { border-bottom: 1px solid var(--border); }
section:last-of-type { border-bottom: none; }

.feature-list { display: flex; flex-direction: column; gap: 2rem; }
.feature-item h3 { margin-bottom: 0.4rem; }
.feature-item p { margin: 0; }

/* Footer */
footer { border-top: 1px solid var(--border); padding: 2rem 0; }
.footer-bottom { text-align: center; }
.notice { color: var(--text-secondary); font-size: 0.85rem; }

/* Code */
code {
    background: var(--bg-secondary);
    padding: 0.15em 0.4em;
    border-radius: 4px;
    font-size: 0.9em;
}

/* Responsive */
@media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.5rem; }
    .py-5 { padding-top: 2.5rem; padding-bottom: 2.5rem; }
    .row { flex-direction: column; gap: 1.5rem; }
}