/* AI Discovery Tutorial - Design System & Theme */

/* === DESIGN TOKENS === */
:root {
  /* Radii */
  --radius-card: 24px;
  --radius-btn: 999px;
  --radius-input: 16px;
  
  /* Spacing */
  --space-1: 8px;
  --space-2: 12px;
  --space-3: 16px;
  --space-4: 24px;
  --space-5: 32px;
  --space-6: 48px;
  --space-7: 64px;
  
  /* Transitions */
  --t: 180ms;
  --ease: cubic-bezier(.2,.8,.2,1);
  
  /* Typography */
  --font-base: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, Arial, sans-serif;
}

/* === LIGHT THEME (DEFAULT) === */
:root,
:root[data-theme="light"] {
  --bg: #F6F7FB;
  --surface-1: #FFFFFF;
  --surface-2: #F1F3F8;
  --surface-glass: rgba(255,255,255,.70);
  
  --text: #10121B;
  --text-2: rgba(16,18,27,.72);
  --text-3: rgba(16,18,27,.52);
  
  --border: rgba(16,18,27,.12);
  --border-hover: rgba(16,18,27,.18);
  
  --accent: #7727D2;
  --accent-hover: #8339D7;
  --accent-soft: rgba(119,39,210,.12);
  --accent-border: rgba(119,39,210,.28);
  
  --shadow-sm: 0 6px 16px rgba(16,18,27,.08);
  --shadow-md: 0 12px 28px rgba(16,18,27,.10);
  --glow: 0 10px 30px rgba(119,39,210,.18);
  
  color-scheme: light;
}

/* === DARK THEME === */
:root[data-theme="dark"] {
  --bg: #050507;
  --surface-1: #0E0E10;
  --surface-2: #141417;
  --surface-glass: rgba(20,20,23,.55);
  
  --text: #F1F0F3;
  --text-2: rgba(241,240,243,.70);
  --text-3: rgba(241,240,243,.50);
  
  --border: rgba(255,255,255,.08);
  --border-hover: rgba(255,255,255,.14);
  
  --accent: #7727D2;
  --accent-hover: #8339D7;
  --accent-soft: rgba(119,39,210,.18);
  --accent-border: rgba(119,39,210,.35);
  
  --shadow-sm: 0 10px 26px rgba(0,0,0,.35);
  --shadow-md: 0 18px 40px rgba(0,0,0,.45);
  --glow: 0 18px 50px rgba(119,39,210,.25);
  
  color-scheme: dark;
}

/* === REDUCED MOTION === */
@media (prefers-reduced-motion: reduce) {
  :root {
    --t: 50ms;
  }
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* === BASE STYLES === */
html, body {
  margin: 0;
  padding: 0;
  font-family: var(--font-base);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

* {
  box-sizing: border-box;
}

/* === PURPLE WAVE BACKGROUND === */
.page-bg {
  background: var(--bg);
  position: relative;
  overflow: hidden;
  min-height: 100vh;
}

.page-bg::before {
  content: "";
  position: absolute;
  inset: -200px;
  pointer-events: none;
  background:
    radial-gradient(800px 600px at 85% 30%, rgba(119,39,210,.30), transparent 60%),
    radial-gradient(900px 700px at 30% 95%, rgba(119,39,210,.18), transparent 62%);
  filter: blur(12px);
  z-index: 0;
}

:root[data-theme="light"] .page-bg::before {
  background:
    radial-gradient(800px 600px at 85% 30%, rgba(119,39,210,.15), transparent 60%),
    radial-gradient(900px 700px at 30% 95%, rgba(119,39,210,.10), transparent 62%);
}

/* === LAYOUT === */
.container-main {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-4);
  position: relative;
  z-index: 1;
}

@media (max-width: 768px) {
  .container-main {
    padding: 0 var(--space-3);
  }
}

.section {
  padding: var(--space-7) 0;
}

@media (max-width: 768px) {
  .section {
    padding: var(--space-6) 0;
  }
}

/* === TYPOGRAPHY === */
.hero-title {
  font-size: clamp(40px, 8vw, 72px);
  font-weight: 600;
  line-height: 1.1;
  margin: 0 0 var(--space-4) 0;
  color: var(--text);
}

.h1 {
  font-size: clamp(32px, 6vw, 56px);
  font-weight: 600;
  line-height: 1.15;
  margin: 0 0 var(--space-3) 0;
  color: var(--text);
}

.h2 {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 600;
  line-height: 1.2;
  margin: 0 0 var(--space-3) 0;
  color: var(--text);
}

.h3 {
  font-size: clamp(20px, 3vw, 28px);
  font-weight: 600;
  line-height: 1.3;
  margin: 0 0 var(--space-2) 0;
  color: var(--text);
}

.subtitle {
  font-size: clamp(16px, 2vw, 20px);
  line-height: 1.6;
  color: var(--text-2);
  margin: 0;
}

.body-text {
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
}

.text-secondary {
  color: var(--text-2);
}

.text-tertiary {
  color: var(--text-3);
}

/* === BUTTONS === */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  height: 48px;
  padding: 0 var(--space-5);
  border-radius: var(--radius-btn);
  font-size: 16px;
  font-weight: 500;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  transition: all var(--t) var(--ease);
  white-space: nowrap;
  min-width: 44px;
}

.btn:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: no-preference) {
  .btn:hover {
    transform: translateY(-1px);
  }
}

/* Button Primary */
.btn-primary {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

.btn-primary:hover {
  background: var(--accent-hover);
  box-shadow: var(--glow);
}

/* Button Secondary */
.btn-secondary {
  background: var(--surface-1);
  color: var(--text);
  border-color: var(--border);
}

.btn-secondary:hover {
  border-color: var(--border-hover);
  box-shadow: var(--shadow-md);
}

/* Button Ghost */
.btn-ghost {
  background: transparent;
  color: var(--text-2);
  border-color: transparent;
}

.btn-ghost:hover {
  color: var(--text);
  background: var(--surface-1);
}

/* Button sizes */
.btn-sm {
  height: 40px;
  padding: 0 var(--space-4);
  font-size: 14px;
}

.btn-lg {
  height: 56px;
  padding: 0 var(--space-6);
  font-size: 18px;
}

/* === CARDS === */
.card {
  background: var(--surface-1);
  border: 1px solid var(--border);
  border-radius: var(--radius-card);
  padding: var(--space-4);
  transition: all var(--t) var(--ease);
}

@media (prefers-reduced-motion: no-preference) {
  .card:hover {
    transform: translateY(-1px);
    border-color: var(--border-hover);
    box-shadow: var(--shadow-md);
  }
}

.card-lg {
  padding: var(--space-5);
}

.card-glass {
  background: var(--surface-glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

/* Support for browsers without backdrop-filter */
@supports not (backdrop-filter: blur(16px)) {
  .card-glass {
    background: var(--surface-1);
  }
}

/* === CHIPS/TAGS === */
.chip {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  height: 32px;
  padding: 0 var(--space-3);
  border-radius: 999px;
  background: var(--accent-soft);
  border: 1px solid var(--accent-border);
  color: var(--text);
  font-size: 14px;
  font-weight: 500;
}

/* === NAVBAR === */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  height: 72px;
  background: transparent;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
}

.navbar-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-4);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  text-decoration: none;
  color: var(--text);
  font-weight: 600;
  font-size: 18px;
}

.navbar-logo {
  height: 32px;
  width: auto;
}

.navbar-links {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  list-style: none;
  margin: 0;
  padding: 0;
}

.navbar-link {
  color: var(--text-2);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--t) var(--ease);
  font-size: 15px;
}

.navbar-link:hover {
  color: var(--text);
}

.navbar-right {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.nvias-logo {
  height: 28px;
  width: auto;
  opacity: 0.7;
  transition: opacity var(--t) var(--ease);
}

.nvias-logo:hover {
  opacity: 1;
}

/* Mobile navbar */
@media (max-width: 768px) {
  .navbar-links {
    display: none;
  }
  
  .navbar-container {
    padding: 0 var(--space-3);
  }
  
  .navbar-brand {
    font-size: 16px;
  }
  
  .navbar-logo {
    height: 28px;
  }
}

/* === THEME TOGGLE === */
.theme-toggle {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--surface-1);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--t) var(--ease);
  color: var(--text-2);
}

.theme-toggle:hover {
  border-color: var(--border-hover);
  color: var(--text);
  box-shadow: var(--shadow-sm);
}

.theme-toggle:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* === GRID === */
.grid {
  display: grid;
  gap: var(--space-4);
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

@media (min-width: 768px) {
  .grid-3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

@media (min-width: 768px) {
  .grid-2 {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* === UTILITIES === */
.text-center {
  text-align: center;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

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

.gap-2 {
  gap: var(--space-2);
}

.gap-3 {
  gap: var(--space-3);
}

.gap-4 {
  gap: var(--space-4);
}

.mt-2 { margin-top: var(--space-2); }
.mt-3 { margin-top: var(--space-3); }
.mt-4 { margin-top: var(--space-4); }
.mt-5 { margin-top: var(--space-5); }
.mt-6 { margin-top: var(--space-6); }

.mb-2 { margin-bottom: var(--space-2); }
.mb-3 { margin-bottom: var(--space-3); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-5 { margin-bottom: var(--space-5); }
.mb-6 { margin-bottom: var(--space-6); }

.p-4 { padding: var(--space-4); }
.p-5 { padding: var(--space-5); }
.p-6 { padding: var(--space-6); }