/* CSS Custom Properties */
:root {
  --color-bg: #fff;
  --color-text: #000;
  --color-text-muted: #555;
  --color-header-bg: #000;
  --color-header-text: #fff;
  --color-border: #e0e0e0;
  --font-sans: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  --max-width: 600px;
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 2rem;
  --spacing-lg: 4rem;
  --spacing-xl: 6rem;
}

/* Reset */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Typography */
h1 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.1;
}

h2 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
  letter-spacing: -0.01em;
}

p {
  margin-bottom: var(--spacing-sm);
}

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

/* Layout */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

main {
  flex: 1;
}

section {
  padding: var(--spacing-lg) 0;
}

/* Header */
header {
  background: var(--color-header-bg);
  color: var(--color-header-text);
  padding: var(--spacing-lg) 0;
}

header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

header h1 {
  color: var(--color-header-text);
}

.header-content .tagline {
  color: rgba(255, 255, 255, 0.7);
  font-size: 1rem;
  margin-top: var(--spacing-xs);
}

/* Navigation */
nav {
  display: flex;
  gap: var(--spacing-md);
}

nav a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
  letter-spacing: 0.02em;
  transition: color 0.2s;
}

nav a:hover {
  color: var(--color-header-text);
}

/* Hero Section */
.hero {
  padding: var(--spacing-xl) 0;
  border-bottom: 1px solid var(--color-border);
}

.hero .intro {
  color: var(--color-text-muted);
  font-size: 1.15rem;
  line-height: 1.7;
  max-width: 500px;
}

.hero .intro:last-child {
  margin-bottom: 0;
}

/* About Section */
#about {
  border-bottom: 1px solid var(--color-border);
}

.about-content {
  color: var(--color-text-muted);
  font-size: 1rem;
  line-height: 1.8;
}

.about-content p:last-child {
  margin-bottom: 0;
}

/* Contact Section */
#contact {
  padding: var(--spacing-lg) 0;
}

.social-links {
  display: flex;
  gap: var(--spacing-md);
}

.social-links a {
  color: var(--color-text);
  font-size: 0.95rem;
  font-weight: 500;
  padding-bottom: 2px;
  border-bottom: 2px solid var(--color-text);
  transition: opacity 0.2s;
}

.social-links a:hover {
  opacity: 0.6;
}

/* Footer */
footer {
  padding: var(--spacing-md) 0;
  border-top: 1px solid var(--color-border);
  margin-top: auto;
}

footer p {
  color: var(--color-text-muted);
  font-size: 0.85rem;
  margin: 0;
}

/* Responsive */
@media (max-width: 600px) {
  h1 {
    font-size: 2rem;
  }

  header .container {
    flex-direction: column;
    gap: var(--spacing-sm);
    text-align: center;
  }

  .social-links {
    flex-wrap: wrap;
    justify-content: center;
  }
}