/* === Custom Properties === */
:root {
    --color-bg: #ffffff;
    --color-bg-dark: #0f172a;
    --color-bg-muted: #f8fafc;
    --color-text: #1e293b;
    --color-text-light: #64748b;
    --color-text-inverse: #f8fafc;
    --color-primary: #4f46e5;
    --color-primary-hover: #4338ca;
    --color-border: #e2e8f0;
    --color-card-bg: #ffffff;
    --font-sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --max-width: 1200px;
    --radius: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
}

/* === Reset === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
    font-family: var(--font-sans);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}
a { color: var(--color-primary); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; display: block; }

/* === Buttons === */
.btn-primary, .btn-secondary {
    display: inline-block;
    padding: 0.625rem 1.5rem;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.9rem;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
}
.btn-primary {
    background: var(--color-primary);
    color: #fff;
}
.btn-primary:hover {
    background: var(--color-primary-hover);
    text-decoration: none;
}
.btn-secondary {
    background: transparent;
    color: var(--color-text);
    border: 1px solid var(--color-border);
}
.btn-secondary:hover {
    background: var(--color-bg-muted);
    text-decoration: none;
}
.btn-large {
    padding: 0.875rem 2rem;
    font-size: 1rem;
}
.btn-inverse {
    background: #fff;
    color: var(--color-primary);
}
.btn-inverse:hover {
    background: #f1f5f9;
    text-decoration: none;
}

/* === Header === */
.site-header {
    border-bottom: 1px solid var(--color-border);
    background: var(--color-bg);
    position: sticky;
    top: 0;
    z-index: 100;
}
.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0.875rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 2rem;
}
.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text);
}
.logo:hover { text-decoration: none; }
.nav-links {
    display: flex;
    gap: 1.5rem;
    flex: 1;
}
.nav-links a {
    color: var(--color-text-light);
    font-size: 0.9rem;
    font-weight: 500;
}
.nav-links a:hover {
    color: var(--color-text);
    text-decoration: none;
}
.nav-actions {
    display: flex;
    gap: 0.75rem;
    align-items: center;
}

/* === Footer === */
.site-footer {
    background: var(--color-bg-dark);
    color: var(--color-text-inverse);
    padding: 4rem 1.5rem 2rem;
    margin-top: 6rem;
}
.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}
.footer-brand p {
    color: var(--color-text-light);
    margin-top: 0.5rem;
    font-size: 0.9rem;
}
.footer-links {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}
.footer-links h4 {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.5rem;
}
.footer-links a {
    color: var(--color-text-light);
    font-size: 0.9rem;
}
.footer-links a:hover {
    color: var(--color-text-inverse);
}
.footer-bottom {
    border-top: 1px solid #334155;
    padding-top: 1.5rem;
    font-size: 0.85rem;
    color: var(--color-text-light);
}

/* === Section Utilities === */
.section {
    padding: 5rem 1.5rem;
    max-width: var(--max-width);
    margin: 0 auto;
}
.section-muted {
    background: var(--color-bg-muted);
}
.section-dark {
    background: var(--color-bg-dark);
    color: var(--color-text-inverse);
}
.section-center {
    text-align: center;
}
.section h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1rem;
}
.section .subtitle {
    font-size: 1.125rem;
    color: var(--color-text-light);
    max-width: 600px;
    margin: 0 auto 3rem;
}

/* === Hero === */
.hero {
    background: var(--color-bg-dark);
    color: var(--color-text-inverse);
    padding: 6rem 1.5rem;
    text-align: center;
}
.hero-inner {
    max-width: 800px;
    margin: 0 auto;
}
.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    line-height: 1.15;
    margin-bottom: 1.5rem;
}
.hero .hero-subtitle {
    font-size: 1.25rem;
    color: #94a3b8;
    margin-bottom: 2.5rem;
    line-height: 1.6;
}
.hero-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* === Card Grid === */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}
.card {
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 2rem;
    box-shadow: var(--shadow);
}
.card h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}
.card p {
    color: var(--color-text-light);
    font-size: 0.95rem;
    line-height: 1.6;
}
.card-icon {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

/* === Steps === */
.steps {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    text-align: center;
}
.step-number {
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    background: var(--color-primary);
    color: #fff;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.125rem;
    margin-bottom: 1rem;
}
.step h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}
.step p {
    color: var(--color-text-light);
    font-size: 0.95rem;
}

/* === Pricing === */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}
.pricing-card {
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 2.5rem 2rem;
    text-align: center;
    box-shadow: var(--shadow);
}
.pricing-card.featured {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-lg);
    position: relative;
}
.pricing-card .plan-name {
    font-size: 1rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-light);
    margin-bottom: 0.5rem;
}
.pricing-card .price {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.25rem;
}
.pricing-card .price-period {
    color: var(--color-text-light);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
}
.pricing-card ul {
    list-style: none;
    text-align: left;
    margin-bottom: 2rem;
}
.pricing-card ul li {
    padding: 0.375rem 0;
    font-size: 0.95rem;
    color: var(--color-text-light);
}
.pricing-card ul li::before {
    content: "\2713  ";
    color: var(--color-primary);
    font-weight: 600;
}

/* === CTA Banner === */
.cta-banner {
    background: var(--color-primary);
    color: #fff;
    padding: 5rem 1.5rem;
    text-align: center;
}
.cta-banner h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 1rem;
}
.cta-banner p {
    font-size: 1.125rem;
    opacity: 0.9;
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* === Feature Detail === */
.feature-detail {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    margin-bottom: 4rem;
}
.feature-detail:nth-child(even) {
    direction: rtl;
}
.feature-detail:nth-child(even) > * {
    direction: ltr;
}
.feature-detail h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}
.feature-detail p {
    color: var(--color-text-light);
    font-size: 1rem;
    line-height: 1.7;
}
.feature-placeholder {
    background: var(--color-bg-muted);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-text-light);
    font-size: 0.9rem;
}

/* === Page Header === */
.page-header {
    text-align: center;
    padding: 4rem 1.5rem 2rem;
}
.page-header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
}
.page-header p {
    font-size: 1.125rem;
    color: var(--color-text-light);
    max-width: 600px;
    margin: 0 auto;
}

/* === Responsive === */
@media (max-width: 768px) {
    .hero h1 { font-size: 2rem; }
    .hero .hero-subtitle { font-size: 1.05rem; }
    .footer-grid { grid-template-columns: 1fr 1fr; gap: 2rem; }
    .steps { grid-template-columns: 1fr; }
    .feature-detail { grid-template-columns: 1fr; }
    .feature-detail:nth-child(even) { direction: ltr; }
    .nav-links { display: none; }
    .section h2 { font-size: 1.5rem; }
}