/* ============================================
   DESIGN SYSTEM — Arctic Frost 🧊
   Middleware Developer CV — Heri Rahmat
   ============================================ */

/* ---------- Google Fonts ---------- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Outfit:wght@400;500;600;700;800&display=swap');

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  line-height: 1.6;
  overflow-x: hidden;
  transition: background-color 0.3s ease, color 0.3s ease;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color 0.3s ease;
}

ul, ol {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

button {
  cursor: pointer;
  border: none;
  outline: none;
  background: none;
  font-family: inherit;
  font-size: inherit;
  transition: all 0.3s ease;
}

input, textarea {
  font-family: inherit;
  font-size: inherit;
  outline: none;
  border: none;
}

/* ============================================
   CSS VARIABLES — Arctic Frost Theme
   ============================================ */
:root {
  /* --- Typography --- */
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-heading: 'Outfit', 'Inter', sans-serif;

  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  --text-hero: 4rem;

  --weight-light: 300;
  --weight-regular: 400;
  --weight-medium: 500;
  --weight-semibold: 600;
  --weight-bold: 700;
  --weight-extrabold: 800;

  /* --- Spacing --- */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;
  --space-section: 100px;

  /* --- Layout --- */
  --max-width: 1200px;
  --nav-height: 72px;

  /* --- Border Radius --- */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* --- Shadows --- */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.2);
  --shadow-glow: 0 0 20px rgba(6, 182, 212, 0.15);

  /* --- Transitions --- */
  --transition-fast: 150ms ease;
  --transition-base: 300ms ease;
  --transition-slow: 500ms ease;

  /* --- Glass --- */
  --glass-blur: 20px;
}

/* ============================================
   DARK THEME (default)
   ============================================ */
[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --bg-elevated: #1e293b;

  --accent-primary: #06b6d4;
  --accent-secondary: #22d3ee;
  --accent-hover: #0891b2;
  --accent-glow: rgba(6, 182, 212, 0.15);

  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --text-accent: #22d3ee;

  --border-color: rgba(255, 255, 255, 0.06);
  --border-hover: rgba(255, 255, 255, 0.12);

  --glass-bg: rgba(15, 23, 42, 0.8);
  --glass-border: rgba(255, 255, 255, 0.06);

  --card-bg: rgba(30, 41, 59, 0.5);
  --card-hover: rgba(30, 41, 59, 0.8);
  --card-border: rgba(255, 255, 255, 0.06);

  --scrollbar-track: #1e293b;
  --scrollbar-thumb: #334155;

  color-scheme: dark;
}

/* ============================================
   LIGHT THEME
   ============================================ */
[data-theme="light"] {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-tertiary: #f1f5f9;
  --bg-elevated: #ffffff;

  --accent-primary: #0891b2;
  --accent-secondary: #06b6d4;
  --accent-hover: #0e7490;
  --accent-glow: rgba(8, 145, 178, 0.1);

  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --text-accent: #0891b2;

  --border-color: rgba(0, 0, 0, 0.08);
  --border-hover: rgba(0, 0, 0, 0.15);

  --glass-bg: rgba(255, 255, 255, 0.8);
  --glass-border: rgba(0, 0, 0, 0.06);

  --card-bg: rgba(255, 255, 255, 0.7);
  --card-hover: rgba(255, 255, 255, 0.95);
  --card-border: rgba(0, 0, 0, 0.06);

  --scrollbar-track: #f1f5f9;
  --scrollbar-thumb: #cbd5e1;

  color-scheme: light;
}

/* ============================================
   BASE STYLES
   ============================================ */
body {
  background-color: var(--bg-primary);
  color: var(--text-secondary);
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  color: var(--text-primary);
  line-height: 1.2;
  font-weight: var(--weight-bold);
}

h1 { font-size: var(--text-hero); }
h2 { font-size: var(--text-4xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }
h5 { font-size: var(--text-lg); }

p {
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ============================================
   SCROLLBAR
   ============================================ */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--scrollbar-track);
}

::-webkit-scrollbar-thumb {
  background: var(--scrollbar-thumb);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent-primary);
}

/* ============================================
   SELECTION
   ============================================ */
::selection {
  background-color: var(--accent-primary);
  color: var(--bg-primary);
}

/* ============================================
   UTILITY CLASSES
   ============================================ */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-xl);
}

.section {
  padding: var(--space-section) 0;
  position: relative;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-4xl);
}

.section-title {
  font-size: var(--text-4xl);
  font-weight: var(--weight-bold);
  color: var(--text-primary);
  margin-bottom: var(--space-md);
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
  border-radius: var(--radius-full);
}

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

/* --- Accent Text --- */
.text-accent {
  color: var(--accent-primary);
}

.text-gradient {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 12px 28px;
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-medium);
  border-radius: var(--radius-lg);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-hover));
  color: #ffffff;
  box-shadow: 0 4px 15px rgba(6, 182, 212, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 25px rgba(6, 182, 212, 0.4);
}

.btn-outline {
  border: 1.5px solid var(--accent-primary);
  color: var(--accent-primary);
  background: transparent;
}

.btn-outline:hover {
  background: var(--accent-glow);
  transform: translateY(-2px);
}

/* --- Cards --- */
.card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  transition: all var(--transition-base);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.card:hover {
  background: var(--card-hover);
  border-color: var(--border-hover);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg), var(--shadow-glow);
}

/* --- Tags / Badges --- */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  font-size: var(--text-xs);
  font-weight: var(--weight-medium);
  color: var(--accent-primary);
  background: var(--accent-glow);
  border: 1px solid rgba(6, 182, 212, 0.2);
  border-radius: var(--radius-full);
}

/* --- Divider --- */
.divider {
  width: 100%;
  height: 1px;
  background: var(--border-color);
  margin: var(--space-3xl) 0;
}

/* --- Screen Reader Only --- */
.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;
}

/* --- Reveal Animation (for Intersection Observer) --- */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.active {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================
   RESPONSIVE FONT SIZES
   ============================================ */
@media (max-width: 1024px) {
  :root {
    --text-hero: 3rem;
    --text-4xl: 2rem;
    --space-section: 80px;
  }
}

@media (max-width: 768px) {
  :root {
    --text-hero: 2.25rem;
    --text-4xl: 1.75rem;
    --text-3xl: 1.5rem;
    --space-section: 60px;
  }

  .container {
    padding: 0 var(--space-md);
  }
}

@media (max-width: 480px) {
  :root {
    --text-hero: 2rem;
    --text-4xl: 1.5rem;
    --space-section: 48px;
  }
}