:root {
  --bg: #ffffff;
  --bg-muted: #f4f6f8;
  --bg-elevated: #ffffff;
  --border: #e2e8f0;
  --text: #0f172a;
  --muted: #475569;
  --accent: #1d4ed8;
  --accent-soft: #eff6ff;
  --accent-hover: #1e40af;
  --radius: 14px;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 10px 30px rgba(15, 23, 42, 0.08);
  --font: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, Cantarell, "Noto Sans",
    sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  min-height: 100%;
  background: var(--bg-muted);
  color: var(--text);
  font-family: var(--font);
  line-height: 1.65;
}

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

a:hover {
  color: var(--accent-hover);
}

.container {
  width: min(1120px, 100% - 2rem);
  margin-inline: auto;
}

.site-header {
  border-bottom: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  position: sticky;
  top: 0;
  z-index: 20;
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.9rem 0;
}

.logo {
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text);
}

.logo span {
  font-weight: 600;
  color: var(--muted);
}

.nav {
  display: flex;
  align-items: center;
  gap: 1.1rem;
  font-size: 0.95rem;
}

.nav a:not(.btn) {
  color: var(--text);
}

.nav a:not(.btn):hover {
  color: var(--accent);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 1.05rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, color 0.15s, box-shadow 0.15s;
}

.btn-primary {
  background: var(--text);
  color: #ffffff;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background: #111c33;
  color: #ffffff;
}

.btn-ghost {
  border-color: var(--border);
  background: #ffffff;
  color: var(--text);
}

.btn-ghost:hover {
  border-color: #cbd5e1;
  background: var(--bg-muted);
}

.btn-danger {
  border-color: #fecaca;
  background: #fff1f2;
  color: #9f1239;
}

.btn-danger:hover {
  border-color: #fca5a5;
  background: #ffe4e6;
}

.hero {
  padding: 3.25rem 0 2rem;
  text-align: center;
  background: linear-gradient(180deg, #ffffff 0%, #f4f6f8 100%);
  border-bottom: 1px solid var(--border);
}

.hero h1 {
  font-size: clamp(2rem, 4vw, 2.65rem);
  margin: 0 0 1rem;
  letter-spacing: -0.03em;
  color: var(--text);
}

.hero .lead {
  color: var(--muted);
  font-size: 1.12rem;
  max-width: 44rem;
  margin: 0 auto 1.5rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
}

.section {
  padding: 2.5rem 0 3rem;
}

.section h2 {
  margin: 0 0 1.25rem;
  font-size: 1.45rem;
  letter-spacing: -0.02em;
}

.course-grid {
  display: grid;
  gap: 1.25rem;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
}

.course-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-elevated);
  display: flex;
  flex-direction: column;
  min-height: 100%;
  box-shadow: var(--shadow-sm);
}

.course-card-body {
  padding: 1.25rem;
  flex: 1;
}

.course-card-body h3 {
  margin: 0 0 0.5rem;
  font-size: 1.1rem;
}

.course-meta {
  margin: 0 0 0.75rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.course-rating {
  font-size: 0.9rem;
}

.stars {
  color: #ca8a04;
}

.course-price {
  margin: 0.75rem 0 0;
  font-weight: 700;
}

.course-card-actions {
  padding: 0 1.25rem 1.25rem;
}

.course-card-actions .btn-primary {
  width: 100%;
}

.muted {
  color: var(--muted);
}

.site-footer {
  border-top: 1px solid var(--border);
  margin-top: 2rem;
  padding: 2rem 0;
  font-size: 0.9rem;
  background: #ffffff;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: space-between;
  align-items: center;
}

.footer-nav .sep {
  margin: 0 0.5rem;
  color: var(--muted);
}

.panel {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-elevated);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.two-col {
  display: grid;
  gap: 1.5rem;
}

@media (min-width: 900px) {
  .two-col {
    grid-template-columns: 280px 1fr;
    align-items: start;
  }
}

.curriculum {
  list-style: none;
  margin: 0;
  padding: 0;
}

.curriculum li {
  margin-bottom: 0.35rem;
}

.curriculum a {
  display: block;
  padding: 0.35rem 0.5rem;
  border-radius: 8px;
  color: var(--text);
}

.curriculum a:hover {
  background: var(--accent-soft);
}

.curriculum a.active {
  background: var(--accent-soft);
  color: var(--accent-hover);
  font-weight: 600;
}

.module-title {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--muted);
  margin: 1rem 0 0.35rem;
}

.module-title:first-child {
  margin-top: 0;
}

.prose {
  max-width: 65ch;
}

.prose ul {
  padding-left: 1.25rem;
}

.form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 520px;
}

.form label {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  font-size: 0.9rem;
  color: var(--text);
}

.form input,
.form textarea,
.form select {
  padding: 0.6rem 0.75rem;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: #ffffff;
  color: var(--text);
  font: inherit;
}

.form textarea {
  min-height: 120px;
  resize: vertical;
}

.form .error,
.error {
  color: #b91c1c;
  font-size: 0.85rem;
}

.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #ffffff;
}

table.simple {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
}

table.simple th,
table.simple td {
  padding: 0.65rem 0.85rem;
  border-bottom: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}

table.simple th {
  background: var(--bg-muted);
  font-weight: 700;
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.15rem 0.55rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 700;
  border: 1px solid var(--border);
  background: #ffffff;
}

.badge-admin {
  border-color: #bfdbfe;
  background: #eff6ff;
  color: #1d4ed8;
}

.layout-split {
  display: grid;
  gap: 1.25rem;
}

@media (min-width: 960px) {
  .layout-split {
    grid-template-columns: 240px 1fr;
    align-items: start;
  }
}

.side-nav {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #ffffff;
  padding: 0.75rem;
  box-shadow: var(--shadow-sm);
}

.side-nav a {
  display: block;
  padding: 0.55rem 0.65rem;
  border-radius: 10px;
  color: var(--text);
}

.side-nav a:hover {
  background: var(--bg-muted);
}

.side-nav a.active {
  background: var(--accent-soft);
  color: var(--accent-hover);
  font-weight: 700;
}

.progress {
  height: 10px;
  border-radius: 999px;
  background: var(--bg-muted);
  border: 1px solid var(--border);
  overflow: hidden;
}

.progress > span {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, #1d4ed8, #2563eb);
}

.cert-print {
  max-width: 900px;
  margin: 0 auto;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2.25rem;
  box-shadow: var(--shadow-md);
}

.cert-print h1 {
  margin: 0 0 0.5rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  font-size: 1.1rem;
  color: var(--muted);
}

.cert-print .name {
  font-size: 2rem;
  margin: 0.75rem 0;
  letter-spacing: -0.02em;
}

.stack {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
}

.page-title {
  margin: 0 0 0.35rem;
  letter-spacing: -0.02em;
}

.subtitle {
  margin: 0 0 1.25rem;
}

@media print {
  .site-header,
  .site-footer,
  .no-print {
    display: none !important;
  }

  body {
    background: #ffffff !important;
  }

  .section {
    padding: 0 !important;
  }
}