/* ========================================
   CSS RESET & VARIABLES
   ======================================== */

:root {
  /* Spacing Scale (8px base unit) */
  --space-xs: 0.5rem;    /* 8px */
  --space-sm: 1rem;      /* 16px */
  --space-md: 1.5rem;    /* 24px */
  --space-lg: 2rem;      /* 32px */
  --space-xl: 3rem;      /* 48px */
  --space-2xl: 4rem;     /* 64px */
  --space-3xl: 5rem;     /* 80px */
  --space-4xl: 6rem;     /* 96px */

  /* Section Spacing */
  --section-padding-y: var(--space-4xl);
  --section-gap: var(--space-xl);

  /* Component Spacing */
  --card-padding: var(--space-md);
  --card-gap: var(--space-lg);

  /* Typography Spacing */
  --heading-margin-bottom: var(--space-lg);
  --paragraph-margin-bottom: var(--space-sm);

  /* Colors */
  --color-bg-dark: #000000;
  --color-bg-light: #ffffff;
  --color-text-dark: #000000;
  --color-text-light: #ffffff;
  --color-accent: #10B981;
  --color-border-light: rgba(255, 255, 255, 0.1);
  --color-border-dark: rgba(0, 0, 0, 0.1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--color-bg-light);
  color: var(--color-text-dark);
  line-height: 1.7;
}

/* ========================================
   TYPOGRAPHY BASE
   ======================================== */

h1, h2, h3, h4, h5, h6 {
  font-weight: 300;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

p {
  font-weight: 300;
  line-height: 1.7;
}

a {
  text-decoration: none;
  color: inherit;
}

/* ========================================
   BUTTON BASE
   ======================================== */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem 2rem;
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  cursor: pointer;
  transition: all 0.3s;
  text-decoration: none;
  border: none;
  min-height: 44px;
  min-width: 44px;
}

.btn--primary {
  background: var(--color-bg-dark);
  color: var(--color-text-light);
}

.btn--primary:hover {
  opacity: 0.8;
}

.btn--secondary {
  background: transparent;
  color: var(--color-text-dark);
  border: 2px solid var(--color-bg-dark);
}

.btn--secondary:hover {
  background: var(--color-bg-dark);
  color: var(--color-text-light);
}

.btn--outline {
  background: transparent;
  color: var(--color-text-dark);
  border: 2px solid var(--color-bg-dark);
}

.btn--outline:hover {
  background: var(--color-bg-dark);
  color: var(--color-text-light);
}

/* Button icon */
.btn .icon {
  width: 16px;
  height: 16px;
}