/* Light theme (default) */
:root {
    --bg: #ffffff;
    --bg-card: #f1f5f9;
    --text: #1e293b;
    --text-dim: #475569;
    --text-head: #0f172a;
    --cyan: #0891b2;
    --green: #059669;
    --blue: #2563eb;
    --border: #cbd5e1;
    --nav-bg: rgba(255, 255, 255, 0.92);
    --tag-bg: rgba(8, 145, 178, 0.08);
    --mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', monospace;
    --sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

/* Dark theme */
[data-theme="dark"] {
    --bg: #0a0e17;
    --bg-card: #111827;
    --text: #cbd5e1;
    --text-dim: #94a3b8;
    --text-head: #f1f5f9;
    --cyan: #22d3ee;
    --green: #34d399;
    --blue: #60a5fa;
    --border: #1e293b;
    --nav-bg: rgba(10, 14, 23, 0.92);
    --tag-bg: rgba(34, 211, 238, 0.1);
}

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

html { scroll-behavior: smooth; }

.skip-link {
    position: absolute;
    top: -100%;
    left: 16px;
    padding: 8px 16px;
    background: var(--cyan);
    color: #fff;
    border-radius: 4px;
    font-size: 14px;
    z-index: 200;
}

.skip-link:focus {
    top: 8px;
    text-decoration: none;
}

body {
    font-family: var(--sans);
    background: var(--bg);
    color: var(--text);
    font-size: 16px;
    line-height: 1.75;
    -webkit-font-smoothing: antialiased;
    transition: background 0.2s, color 0.2s;
}

a { color: var(--cyan); text-decoration: none; transition: color 0.15s; }
a:hover { text-decoration: underline; }

:focus-visible {
    outline: 2px solid var(--cyan);
    outline-offset: 2px;
}

.container {
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Navigation */
nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: var(--nav-bg);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    z-index: 100;
    padding: 16px 0;
}

nav .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

nav .logo {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-head);
    letter-spacing: -0.3px;
}

nav .links {
    display: flex;
    gap: 24px;
    align-items: center;
    font-size: 15px;
}

nav .links a { color: var(--text-dim); }
nav .links a:hover { color: var(--text-head); text-decoration: none; }

.nav-btn {
    padding: 5px 12px;
    border: 1px solid var(--border);
    border-radius: 4px;
    font-size: 13px;
    color: var(--text-dim);
    background: transparent;
    cursor: pointer;
    font-family: inherit;
    transition: color 0.15s, border-color 0.15s;
}

.nav-btn:hover {
    color: var(--text-head);
    border-color: var(--text-dim);
    text-decoration: none;
}

/* Mobile menu toggle */
.menu-toggle {
    display: none;
    background: none;
    border: 1px solid var(--border);
    border-radius: 4px;
    color: var(--text-dim);
    font-size: 22px;
    padding: 4px 10px;
    cursor: pointer;
    line-height: 1;
}

.menu-toggle:hover { color: var(--text-head); border-color: var(--text-dim); }

/* Hero */
.hero {
    padding: 160px 0 100px;
    text-align: center;
}

.hero h1 {
    font-size: 52px;
    font-weight: 800;
    color: var(--text-head);
    letter-spacing: -1.5px;
    line-height: 1.15;
    margin-bottom: 24px;
}

.hero h1 em {
    font-style: normal;
    background: linear-gradient(135deg, var(--cyan), var(--blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero .subtitle {
    font-size: 20px;
    color: var(--text-dim);
    max-width: 660px;
    margin: 0 auto 40px;
    line-height: 1.7;
}

.hero .cta {
    display: inline-flex;
    gap: 12px;
}

.btn {
    display: inline-block;
    padding: 13px 30px;
    border-radius: 6px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: all 0.15s;
}

.btn-primary {
    background: var(--cyan);
    color: #fff;
}

[data-theme="dark"] .btn-primary {
    color: #0a0e17;
}

.btn-primary:hover {
    opacity: 0.9;
    text-decoration: none;
    transform: translateY(-1px);
}

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

.btn-ghost:hover {
    border-color: var(--text-dim);
    text-decoration: none;
    transform: translateY(-1px);
}

/* Sections */
section {
    padding: 88px 0;
}

section:nth-of-type(even) {
    background: var(--bg-card);
}

section:nth-of-type(even) .problem-card,
section:nth-of-type(even) .product-card,
section:nth-of-type(even) .compliance-item {
    background: var(--bg);
}

section h2 {
    font-size: 34px;
    font-weight: 700;
    color: var(--text-head);
    letter-spacing: -0.5px;
    margin-bottom: 14px;
}

section .section-sub {
    font-size: 17px;
    color: var(--text-dim);
    margin-bottom: 40px;
    line-height: 1.7;
}

/* Problem */
.problem-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.problem-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 28px;
    transition: background 0.2s, border-color 0.2s, transform 0.2s, box-shadow 0.2s;
}

.problem-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
    border-color: var(--cyan);
}

[data-theme="dark"] .problem-card:hover {
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.25);
}

.problem-card .num {
    font-family: var(--mono);
    font-size: 14px;
    color: var(--cyan);
    font-weight: 600;
    margin-bottom: 12px;
}

.problem-card h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-head);
    margin-bottom: 10px;
}

.problem-card p {
    font-size: 15px;
    color: var(--text-dim);
    line-height: 1.65;
}

/* Products */
.product-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 36px;
    transition: border-color 0.2s, background 0.2s, transform 0.2s, box-shadow 0.2s;
}

.product-card:hover {
    border-color: var(--cyan);
    transform: translateY(-3px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}

[data-theme="dark"] .product-card:hover {
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.25);
}

.product-card .tag {
    display: inline-block;
    font-family: var(--mono);
    font-size: 12px;
    font-weight: 600;
    color: var(--cyan);
    background: var(--tag-bg);
    padding: 3px 10px;
    border-radius: 4px;
    margin-bottom: 14px;
}

.product-card h3 {
    font-size: 22px;
    font-weight: 700;
    color: var(--text-head);
    margin-bottom: 10px;
}

.product-card p {
    font-size: 15px;
    color: var(--text-dim);
    line-height: 1.65;
    margin-bottom: 18px;
}

.product-card .features {
    list-style: none;
    font-size: 15px;
    color: var(--text);
}

.product-card .features li {
    padding: 5px 0;
}

.product-card .features li::before {
    content: '\2713 ';
    color: var(--green);
    font-weight: 700;
    margin-right: 8px;
}

/* Stats */
.stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    text-align: center;
    padding: 48px 0;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.stats .stat-val {
    font-size: 44px;
    font-weight: 800;
    font-family: var(--mono);
    color: var(--text-head);
    background: linear-gradient(135deg, var(--cyan), var(--blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stats .stat-label {
    font-size: 14px;
    color: var(--text-dim);
    margin-top: 8px;
}

/* Compliance */
.compliance-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 14px;
}

.compliance-item {
    display: flex;
    align-items: baseline;
    gap: 12px;
    font-size: 15px;
    color: var(--text);
    padding: 16px 20px;
    background: var(--bg-card);
    border-radius: 8px;
    border: 1px solid var(--border);
    transition: background 0.2s, border-color 0.2s, transform 0.2s;
}

.compliance-item:hover {
    border-color: var(--cyan);
    transform: translateX(4px);
}

.compliance-item .code {
    font-family: var(--mono);
    font-size: 13px;
    font-weight: 600;
    color: var(--cyan);
    white-space: nowrap;
}

/* Contact / CTA */
.cta-section {
    text-align: center;
    padding: 80px 0;
}

.cta-section h2 {
    margin-bottom: 16px;
}

.cta-section p {
    color: var(--text-dim);
    margin-bottom: 36px;
    font-size: 17px;
}

.cta-section .cta {
    display: inline-flex;
    gap: 12px;
}

/* Footer */
footer {
    border-top: 1px solid var(--border);
    padding: 48px 0;
    text-align: center;
    font-size: 14px;
    color: var(--text-dim);
}

footer a { color: var(--text-dim); }
footer a:hover { color: var(--text); }

/* Responsive */
@media (max-width: 768px) {
    .hero { padding: 130px 0 72px; }
    .hero h1 { font-size: 32px; letter-spacing: -1px; }
    .hero .subtitle { font-size: 17px; }
    .problem-grid { grid-template-columns: 1fr; }
    .stats { grid-template-columns: 1fr; gap: 24px; }
    .compliance-list { grid-template-columns: 1fr; }
    section { padding: 64px 0; }
    section h2 { font-size: 28px; }

    .menu-toggle { display: block; }

    nav .links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        flex-direction: column;
        background: var(--nav-bg);
        backdrop-filter: blur(12px);
        border-bottom: 1px solid var(--border);
        padding: 16px 24px;
        gap: 12px;
        font-size: 15px;
    }

    nav .links.open {
        display: flex;
    }

    nav .links a,
    nav .links .nav-btn {
        width: fit-content;
    }
}