:root {
  --color-bg: #000000;
  --color-text: #e0e0e0;
  --color-accent: #FFA726;
  --color-card-bg: #111111;
  --color-card-hover: #1a1a1a;
  --font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}

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

body {
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-family);
  line-height: 1.6;
}

.container {
  width: 90%;
  max-width: 1100px;
  margin: 0 auto;
}

/* Header */
.site-header {
  background: rgba(0,0,0,0.8);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 1px 4px rgba(0,0,0,0.4);
}
.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
}
.brand {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--color-accent);
  text-decoration: none;
}
.main-nav ul {
  list-style: none;
  display: flex;
  gap: 1.5rem;
}
.main-nav a {
  color: var(--color-text);
  text-decoration: none;
  position: relative;
  padding: 0.5rem 0;
  transition: color 0.3s;
}
.main-nav a.active,
.main-nav a:hover {
  color: var(--color-accent);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 30px;
  height: 24px;
  background: transparent;
  border: none;
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  height: 3px;
  background: var(--color-text);
  border-radius: 3px;
  transition: transform 0.3s, opacity 0.3s;
}

/* Hero */
.hero {
  position: relative;
  padding: 6rem 0;
  text-align: center;
  overflow: hidden;
}
.hero-content {
  position: relative;
  z-index: 2;
}
.hero h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--color-accent);
}
.hero p {
  font-size: 1.2rem;
  margin-bottom: 2rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.cta-button {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  background: var(--color-accent);
  color: #000;
  font-weight: 600;
  border-radius: 25px;
  text-decoration: none;
  transition: background 0.3s ease, transform 0.3s ease;
}
.cta-button:hover {
  background: #ffb94d;
  transform: translateY(-2px);
}

/* Hero graphic - luminous arc */
.hero-graphic {
  position: absolute;
  bottom: -30%;
  left: 50%;
  transform: translateX(-50%);
  width: 200%;
  height: 100%;
  background: radial-gradient(circle at center top, rgba(255,167,38,0.6) 0%, rgba(255,167,38,0.05) 60%, transparent 70%);
  filter: blur(120px);
  z-index: 1;
}

/* Section list */
.section-list {
  padding: 4rem 0;
}
.section-list h2 {
  font-size: 2rem;
  margin-bottom: 2rem;
  text-align: center;
}
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
}
.card {
  background: var(--color-card-bg);
  padding: 1.5rem;
  border-radius: 12px;
  text-decoration: none;
  color: var(--color-text);
  box-shadow: 0 2px 4px rgba(0,0,0,0.4);
  transition: transform 0.3s ease, box-shadow 0.3s ease, background 0.3s ease;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}
.card h3 {
  margin-bottom: 0.75rem;
  color: var(--color-accent);
  font-size: 1.25rem;
}
.card p {
  flex-grow: 1;
  color: var(--color-text);
  font-size: 0.9rem;
}
.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 16px rgba(0,0,0,0.6);
  background: var(--color-card-hover);
}

/* Breadcrumb */
.breadcrumb {
  font-size: 0.9rem;
  margin-bottom: 1rem;
}
.breadcrumb a {
  color: var(--color-accent);
  text-decoration: none;
}
.breadcrumb .separator {
  margin: 0 0.5rem;
  color: var(--color-text);
}

/* Page content */
.page-main {
  padding: 2rem 0 4rem;
}
.page-main h1 {
  font-size: 2rem;
  margin-bottom: 1rem;
  color: var(--color-accent);
}
.content {
  background: var(--color-card-bg);
  padding: 2rem;
  border-radius: 12px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.4);
}
.content p,
.content li {
  margin-bottom: 0.75rem;
  font-size: 1rem;
  line-height: 1.6;
}
.content ul,
.content ol {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}
.content blockquote {
  border-left: 3px solid var(--color-accent);
  padding-left: 1rem;
  margin: 1rem 0;
  color: var(--color-text);
  background: #0d0d0d;
  border-radius: 4px;
}
.content mark.highlight-blue {
  background-color: rgba(255,167,38,0.3);
  padding: 0.1rem 0.2rem;
  border-radius: 3px;
}
.content mark.highlight-yellow {
  background-color: rgba(255,167,38,0.5);
  padding: 0.1rem 0.2rem;
  border-radius: 3px;
}
.content details {
  margin-bottom: 1rem;
  background: #0d0d0d;
  border-radius: 6px;
  padding: 0.5rem 1rem;
}
.content details summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--color-accent);
}
.content table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1rem;
}
.content th, .content td {
  border: 1px solid #222;
  padding: 0.5rem;
  text-align: left;
}
.content th {
  background: #111;
}
.content img {
  max-width: 100%;
  border-radius: 8px;
  margin: 1rem 0;
}

/* Footer */
.site-footer {
  background: #050505;
  padding: 2rem 0;
  text-align: center;
  font-size: 0.9rem;
  color: #888;
}

/* Responsive navigation */
@media (max-width: 768px) {
  .main-nav ul {
    flex-direction: column;
    background: #000;
    position: absolute;
    top: 100%;
    right: 0;
    width: 200px;
    padding: 1rem;
    display: none;
  }
  .main-nav.open ul {
    display: flex;
  }
  .nav-toggle {
    display: flex;
  }
  .main-nav ul li {
    margin: 0.5rem 0;
  }
}