/* Jane Street-inspired minimal design */
:root {
  --color-primary: #2c3e50;
  --color-secondary: #34495e;
  --color-accent: #e74c3c;
  --color-text: #2c3e50;
  --color-text-light: #7f8c8d;
  --color-background: #f8f9fa;
  --color-white: #ffffff;
  --color-border: #ecf0f1;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-serif: "Times New Roman", Georgia, serif;
}

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

body {
  font-family: var(--font-sans);
  line-height: 1.6;
  color: var(--color-text);
  background: #f4f6f8;
  background-image:
    linear-gradient(135deg, #f4f6f8 0%, #e9ecef 25%, #f8f9fa 50%, #e9ecef 75%, #f4f6f8 100%);
  background-size: 400% 400%;
  animation: subtleGradient 20s ease infinite;
  min-height: 100vh;
}

@keyframes subtleGradient {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

.container {
  max-width: 900px;
  margin: 2rem auto;
  background: var(--color-white);
  box-shadow:
    0 20px 60px rgba(0, 0, 0, 0.05),
    0 8px 25px rgba(0, 0, 0, 0.08);
  border-radius: 8px;
  overflow: hidden;
  min-height: calc(100vh - 4rem);
  border: 1px solid rgba(0, 0, 0, 0.04);
}

/* Header & Navigation */
header {
  background: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 2rem;
}

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

nav h1 a {
  color: var(--color-primary);
  text-decoration: none;
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 700;
}

nav ul {
  list-style: none;
  display: flex;
  gap: 2rem;
}

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

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

/* Hero Section */
.hero {
  text-align: center;
  padding: 4rem 2rem;
  background: linear-gradient(135deg, #fafbfc 0%, #f8f9fa 50%, #f1f3f4 100%);
  border-bottom: 1px solid var(--color-border);
}

.hero h1 {
  font-family: var(--font-serif);
  font-size: 2.5rem;
  color: var(--color-primary);
  margin-bottom: 1rem;
  letter-spacing: -0.025em;
}

.hero .tagline {
  font-size: 1.2rem;
  color: var(--color-text-light);
  margin: 0;
}

/* Content */
.content {
  padding: 3rem 2rem;
}

.content h1 {
  font-family: var(--font-serif);
  font-size: 2rem;
  color: var(--color-primary);
  margin-bottom: 1.5rem;
  border-bottom: 2px solid var(--color-border);
  padding-bottom: 0.5rem;
}

.content h2 {
  font-size: 1.5rem;
  color: var(--color-secondary);
  margin: 2rem 0 1rem 0;
}

.content p {
  margin-bottom: 1.5rem;
  line-height: 1.7;
}

.content ul {
  margin: 1rem 0 1.5rem 2rem;
}

.content li {
  margin-bottom: 0.5rem;
}

.content a {
  color: var(--color-accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease;
}

.content a:hover {
  border-bottom-color: var(--color-accent);
}

/* Footer */
footer {
  background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
  text-align: center;
  padding: 2rem;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-light);
  font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
  nav {
    flex-direction: column;
    gap: 1rem;
  }

  nav ul {
    gap: 1rem;
  }

  .hero {
    padding: 2rem 1rem;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .content {
    padding: 2rem 1rem;
  }
}