:root {
    --gdw-red: #C41230;
    --gdw-gold: #F5A623;
    --gdw-dark: #1A1A2E;
    --gdw-gradient: linear-gradient(135deg, var(--gdw-gold) 0%, var(--gdw-red) 100%);
    --border: #e7e7ee;
    --bg-soft: #faf9fc;
    --text-muted: #6b6b7a;
    --radius: 10px;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: "Segoe UI", Roboto, -apple-system, sans-serif;
    color: var(--gdw-dark);
    background: #fff;
    line-height: 1.6;
}

a { color: var(--gdw-red); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------- Top nav ---------- */
.topnav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 28px;
    background: var(--gdw-dark);
    color: #fff;
}
.topnav .brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    font-size: 1.15rem;
    color: #fff;
}
.topnav .brand .badge {
    background: var(--gdw-gradient);
    padding: 4px 10px;
    border-radius: 6px;
    font-size: 0.85rem;
}
.topnav nav a {
    color: #eee;
    margin-left: 22px;
    font-weight: 500;
}
.topnav nav a:hover { color: var(--gdw-gold); text-decoration: none; }

/* ---------- Layout: sidebar + content ---------- */
.layout {
    display: flex;
    max-width: 1200px;
    margin: 0 auto;
    align-items: flex-start;
}
.sidebar {
    width: 260px;
    flex-shrink: 0;
    border-right: 1px solid var(--border);
    padding: 20px 14px;
    position: sticky;
    top: 0;
    max-height: 100vh;
    overflow-y: auto;
}
.sidebar h3 {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin: 18px 8px 8px;
}
.sidebar ul { list-style: none; margin: 0; padding: 0; }
.sidebar li a {
    display: block;
    padding: 9px 12px;
    border-radius: 8px;
    color: var(--gdw-dark);
    font-size: 0.95rem;
}
.sidebar li a:hover { background: var(--bg-soft); text-decoration: none; }
.sidebar li a.active {
    background: var(--gdw-gradient);
    color: #fff;
    font-weight: 600;
}
.sidebar ul.subnav {
    margin: 2px 0 6px 10px;
    padding-left: 10px;
    border-left: 2px solid var(--border);
}
.sidebar ul.subnav li a {
    padding: 6px 10px;
    font-size: 0.85rem;
    color: var(--text-muted);
}
.sidebar ul.subnav li a:hover {
    color: var(--gdw-red);
    background: var(--bg-soft);
}
.sidebar .cert-link {
    display: block;
    margin-top: 20px;
    text-align: center;
    padding: 10px 12px;
    border-radius: 8px;
    background: var(--gdw-gradient);
    color: #fff !important;
    font-weight: 600;
}

.content {
    flex: 1;
    padding: 32px 40px;
    min-width: 0;
}
.content h1 { margin-top: 0; }
.content h2 { scroll-margin-top: 20px; margin-top: 40px; padding-top: 10px; border-top: 1px solid var(--border); }
.content h2:first-of-type { border-top: none; margin-top: 24px; }
.content pre, .content code {
    background: var(--bg-soft);
    border: 1px solid var(--border);
    border-radius: 6px;
}
.content pre { padding: 14px; overflow-x: auto; }
.content code { padding: 2px 6px; font-size: 0.9em; }

.lesson-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid var(--border);
}
.lesson-nav a {
    padding: 10px 18px;
    border-radius: 8px;
    background: var(--bg-soft);
    color: var(--gdw-dark);
    font-weight: 600;
}
.lesson-nav a:hover { background: var(--gdw-gradient); color: #fff; text-decoration: none; }

/* ---------- Homepage / course cards ---------- */
.hero {
    background: var(--gdw-gradient);
    color: #fff;
    padding: 60px 28px;
    text-align: center;
}
.hero h1 { font-size: 2.4rem; margin: 0 0 12px; }
.hero p { font-size: 1.1rem; opacity: 0.95; }

.course-grid {
    max-width: 1100px;
    margin: 40px auto;
    padding: 0 28px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 22px;
}
.course-card {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    transition: transform 0.15s, box-shadow 0.15s;
}
.course-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 28px rgba(196, 18, 48, 0.12);
}
.course-card .icon {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--gdw-red);
}
.course-card h3 { margin: 10px 0 6px; }
.course-card p { color: var(--text-muted); font-size: 0.95rem; }
.course-card .start-link { display: inline-block; margin-top: 10px; font-weight: 600; }

/* ---------- Certificate / payment page ---------- */
.cert-box {
    max-width: 560px;
    margin: 40px auto;
    padding: 32px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    text-align: center;
}
.cert-box .price {
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--gdw-red);
    margin: 10px 0 20px;
}
.cert-actions { display: flex; flex-direction: column; gap: 14px; margin-top: 22px; }
.btn {
    display: inline-block;
    padding: 12px 20px;
    border-radius: 8px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}
.btn-primary {
    background: var(--gdw-gradient);
    color: #fff !important;
}
.btn-primary:hover { opacity: 0.92; text-decoration: none; }
.btn-whatsapp {
    background: #25D366;
    color: #fff !important;
}
.btn-whatsapp:hover { opacity: 0.9; text-decoration: none; }

/* ---------- Certificate request form ---------- */
.cert-form {
    display: flex;
    flex-direction: column;
    gap: 14px;
    text-align: left;
    margin-top: 20px;
}
.cert-form input,
.cert-form select {
    padding: 11px 14px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 0.95rem;
    font-family: inherit;
}
.cert-form input:focus,
.cert-form select:focus {
    outline: none;
    border-color: var(--gdw-red);
}
.cert-note {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 18px;
}

/* ---------- Footer ---------- */
.site-footer {
    text-align: center;
    padding: 26px;
    color: var(--text-muted);
    font-size: 0.85rem;
    border-top: 1px solid var(--border);
    margin-top: 40px;
}

@media (max-width: 800px) {
    .layout { flex-direction: column; }
    .sidebar { width: 100%; position: static; max-height: none; border-right: none; border-bottom: 1px solid var(--border); }
    .content { padding: 24px 20px; }
}