/* ============================================================================
   Font Face Declarations - Inter
   ============================================================================ */

@font-face {
  font-family: 'Inter';
  src: url('../assets/fonts/Inter-Light.ttf') format('truetype');
  font-weight: 300;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Inter';
  src: url('../assets/fonts/Inter-Regular.ttf') format('truetype');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Inter';
  src: url('../assets/fonts/Inter-Medium.ttf') format('truetype');
  font-weight: 500;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Inter';
  src: url('../assets/fonts/Inter-SemiBold.ttf') format('truetype');
  font-weight: 600;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Inter';
  src: url('../assets/fonts/Inter-Bold.ttf') format('truetype');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Inter';
  src: url('../assets/fonts/Inter-ExtraBold.ttf') format('truetype');
  font-weight: 800;
  font-style: normal;
  font-display: swap;
}

/* ============================================================================
   Base Styles
   ============================================================================ */

html {
  font-size: 16px;
}

body {
  font-family: var(--font-body);
  font-weight: var(--font-normal);
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  min-height: 100vh;
  position: relative;
  /* Theme switch transition — smooth color change on toggle.
     Does NOT fire on initial load (anti-flash script sets attribute before CSS processes). */
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* Subtle grain texture overlay */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  opacity: 0.03;
  z-index: -1;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%' height='100%' filter='url(%23noise)'/%3E%3C/svg%3E");
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: var(--font-bold);
  line-height: var(--line-height-tight);
  color: var(--color-text-primary);
}

h1 {
  font-size: var(--text-4xl);
  font-weight: var(--font-extrabold);
}

h2 {
  font-size: var(--text-3xl);
}

h3 {
  font-size: var(--text-2xl);
}

h4 {
  font-size: var(--text-xl);
}

p {
  color: var(--color-text-secondary);
  line-height: var(--line-height-relaxed);
}

a {
  color: var(--color-brand-accent);
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-brand);
}

/* Focus styles for accessibility */
:focus-visible {
  outline: 2px solid var(--color-brand);
  outline-offset: 2px;
}

/* Selection */
::selection {
  background-color: var(--color-brand);
  color: var(--color-on-brand);
}

/* Container */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

/* Section base */
section {
  padding: var(--space-16) 0;
}

@media (min-width: 768px) {
  section {
    padding: var(--space-20) 0;
  }
}

@media (min-width: 1024px) {
  h1 {
    font-size: var(--text-5xl);
  }

  h2 {
    font-size: var(--text-4xl);
  }

  section {
    padding: var(--space-24) 0;
  }
}

/* Section titles */
.section-header {
  text-align: center;
  margin-bottom: var(--space-12);
}

.section-title {
  margin-bottom: var(--space-4);
}

.section-subtitle {
  font-size: var(--text-lg);
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* Visually hidden (for screen readers) */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ============================================================================
   Internal Page Layout
   ============================================================================ */

.page-internal {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.page-internal-main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-8) 0;
}

/* Skip to content — acessibilidade */
.skip-to-content {
  position: absolute;
  top: -100%;
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-brand);
  color: var(--color-on-brand);
  padding: var(--space-3) var(--space-5);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: var(--font-semibold);
  z-index: 10001;
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip-to-content:focus {
  top: var(--space-3);
}