:root {
  --bg-color: #ffffff;
  --surface-color: #ffffff;
  --surface-alt: #ffffff;
  
  /* Klasyczny Microsoft Blue (Gwarantuje zgodność kontrastu > 4.5:1) */
  --accent: #0078D4; /* Wymagany przez usera niebieski */
  --accent-hover: #005A9E; /* Bezpiecznie przyciemniony wariant dla przycisków na :hover */
  --accent-light: #F3F9FD; /* Tła podrzędne komponujące się z niebieskim */
  
  /* Złagodzone ramki i odpowiednio ciemne szarości tekstu dla Lighthouse */
  --border-color: #D2E8F8; 
  --border-strong: #96C6EB;
  --text-main: #0f172a; /* Perfekcyjny kontrast czerni */
  --text-muted: #334155; /* Szarość Slate-700 */
  
  --font-main: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-main);
  background-color: var(--bg-color);
  color: var(--text-main);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

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

/* Header / Hero Area */
.hero {
  padding: 6rem 2rem 5rem;
  background-color: var(--bg-color);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-content {
  max-width: 1200px;
  width: 100%;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 4rem;
}

.hero-text {
  text-align: left;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  justify-content: flex-start;
  flex-wrap: wrap;
}

.hero-buttons .cta-button {
  flex: 1;
  min-width: 230px;
  max-width: 260px;
}

.hero-image {
  position: relative;
  display: inline-block;
  width: 100%;
  border-radius: 12px;
  box-shadow: 0 12px 24px -6px rgba(15, 23, 42, 0.1), 0 0 0 1px rgba(15, 23, 42, 0.05);
  transition: transform 0.4s ease, box-shadow 0.4s ease;
}

.hero-image img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 12px;
}

/* Duotone Color Tint Overlay */
.hero-image::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  border-radius: 12px;
  background-color: var(--accent);
  mix-blend-mode: color;
  opacity: 0.8; /* Subtle blue tint */
  pointer-events: none;
  transition: opacity 0.4s ease;
}

.hero-image:hover {
  transform: translateY(-4px);
  box-shadow: 0 20px 40px -8px rgba(0, 120, 212, 0.15), 0 0 0 1px rgba(15, 23, 42, 0.05);
}

.hero-image:hover::after {
  opacity: 0; /* Reveal natural image colors on hover */
}

.hero-title {
  font-size: 4rem;
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 1.5rem;
  color: var(--text-main);
  letter-spacing: -0.04em;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-muted);
  margin-bottom: 2.5rem;
  font-weight: 400;
  line-height: 1.6;
}

.cta-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 1rem 2.5rem;
  font-size: 1.125rem;
  font-weight: 600;
  color: #ffffff;
  background-color: var(--accent);
  border: none;
  border-radius: 0;
  text-decoration: none;
  transition: background-color 0.2s ease;
}

.cta-button:hover {
  background-color: var(--accent-hover);
  color: #ffffff;
  text-decoration: none;
}

.cta-button-outline {
  background-color: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
}

.cta-button-outline:hover {
  background-color: var(--accent-light);
  color: var(--accent-hover);
}

/* Layout */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 4rem 2rem;
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 4rem;
  align-items: start;
}

/* Sidebar ToC */
.sidebar {
  position: sticky;
  top: 2rem;
  padding: 2rem;
  background-color: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 0;
}

.sidebar h3 {
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent);
  margin-bottom: 1.5rem;
  font-weight: 700;
}

.sidebar ul {
  list-style: none;
}

.sidebar li {
  margin-bottom: 0.75rem;
}

.sidebar a {
  color: var(--text-main);
  font-size: 0.95rem;
  font-weight: 400;
  text-decoration: none;
  display: block;
}

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

/* Main Content Area */
.content-wrapper {
  padding-bottom: 4rem;
}

.section {
  margin-bottom: 4rem;
}

.section h2 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  color: var(--text-main);
  font-weight: 700;
  letter-spacing: -0.02em;
  border-bottom: 2px solid var(--accent);
  padding-bottom: 0.75rem;
  display: inline-block;
  width: 100%;
}

.section h3 {
  font-size: 1.25rem;
  margin-top: 2rem;
  margin-bottom: 1rem;
  color: var(--text-main);
  font-weight: 600;
}

.section p {
  margin-bottom: 1.5rem;
  font-size: 1.125rem;
  color: var(--text-muted);
}

.section ul {
  margin-left: 2rem;
  margin-bottom: 1.5rem;
  color: var(--text-muted);
}

.section li {
  margin-bottom: 0.5rem;
  font-size: 1.125rem;
}

.glass-box {
  background-color: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 0;
  padding: 2rem;
  margin: 2rem 0;
}

.glass-box.accent {
  background-color: var(--bg-color);
  border: 1px solid var(--border-strong);
  border-left: 4px solid var(--accent);
}

.glass-box h3 {
  margin-top: 0;
  color: var(--accent);
  font-size: 1.25rem;
  margin-bottom: 1rem;
}

.highlight {
  background-color: var(--accent-light);
  color: var(--accent-hover);
  padding: 0.2rem 0.4rem;
  font-weight: 600;
  border-radius: 0;
}

.alert-box {
  background-color: var(--accent-light);
  border: 1px solid var(--border-strong);
  border-left: 4px solid var(--accent);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  border-radius: 0;
}

.alert-box p {
  margin-bottom: 0;
  color: var(--text-main);
  font-weight: 500;
  font-size: 1.05rem;
}

/* Tables (Flat) */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  border: 1px solid var(--border-color);
}

th, td {
  padding: 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

th {
  background-color: var(--accent-light);
  font-weight: 600;
  color: var(--accent-hover);
}

tr:last-child td {
  border-bottom: none;
}

/* Footer */
footer {
  background-color: var(--bg-color);
  border-top: 1px solid var(--border-color);
  padding: 4rem 2rem;
  text-align: center;
}

.footer-content p {
  color: var(--text-muted);
  font-size: 0.875rem;
}

/* Media Queries */
@media (max-width: 1024px) {
  .container {
    grid-template-columns: 220px 1fr;
    gap: 2rem;
    padding: 3rem 2rem;
  }
}

@media (max-width: 768px) {
  .container {
    grid-template-columns: 1fr;
    padding: 2rem 1.5rem;
  }
  .sidebar {
    display: none;
  }
  .hero {
    padding: 4rem 1.5rem 3rem;
  }
  .hero-content {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  .hero-text {
    text-align: left;
  }
  .hero-buttons {
    flex-direction: column;
    width: 100%;
  }
  .hero-buttons .cta-button {
    width: 100%;
    max-width: 100%;
    min-width: unset;
  }
  .hero-title {
    font-size: 2.5rem;
  }
  .section h2 {
    font-size: 1.75rem;
  }
}