/* ==========================================================================
   NOWWHAT? — Premium Design System & Core Styles
   Palette: Dark sophisticated background, warm cream typography, subtle orange/amber accent
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@300;400;500;600;700;800&family=Space+Grotesk:wght@500;700&display=swap');

:root {
  /* Surface colors */
  --bg-deep: #080A0E;
  --bg-surface: #10131A;
  --bg-surface-elevated: #161B26;
  --bg-card: rgba(22, 27, 38, 0.7);
  --bg-card-hover: rgba(28, 35, 48, 0.85);
  --bg-glass: rgba(16, 19, 26, 0.75);

  /* Borders & Dividers */
  --border-subtle: rgba(255, 255, 255, 0.07);
  --border-glow: rgba(255, 122, 48, 0.25);
  --border-focus: #FF7A30;

  /* Typography */
  --font-main: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'Space Grotesk', monospace;

  /* Warm Cream Text System */
  --text-primary: #F8F6F0;
  --text-secondary: #DDD8CE;
  --text-muted: #9C968A;
  --text-faint: #67635A;

  /* Accents */
  --accent-primary: #FF7A30;
  --accent-hover: #FF9254;
  --accent-glow: rgba(255, 122, 48, 0.35);
  --accent-amber: #F59E0B;
  --accent-warm-cream: #FFF4E5;

  /* Category colors */
  --cat-watch: #B068F8;
  --cat-make: #FF7A30;
  --cat-move: #10B981;
  --cat-learn: #38BDF8;
  --cat-play: #F43F5E;
  --cat-create: #A855F7;
  --cat-connect: #06B6D4;
  --cat-explore: #FBBF24;
  --cat-relax: #14B8A6;
  --cat-improve: #818CF8;

  /* Radii & Shadows */
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 9999px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.35);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.6);
  --shadow-glow: 0 0 35px rgba(255, 122, 48, 0.18);

  /* Transitions */
  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  font-family: var(--font-main);
  background-color: var(--bg-deep);
  color: var(--text-primary);
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: 
    radial-gradient(circle at 15% 15%, rgba(255, 122, 48, 0.04) 0%, transparent 40%),
    radial-gradient(circle at 85% 65%, rgba(245, 158, 11, 0.03) 0%, transparent 45%),
    var(--bg-deep);
  background-attachment: fixed;
  overflow-x: hidden;
  line-height: 1.6;
}

/* Typography styles */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.025em;
}

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

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

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  outline: none;
  background: transparent;
}

input, textarea, select {
  font-family: inherit;
  color: var(--text-primary);
  border: none;
  outline: none;
}

/* Layout Utilities */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 clamp(1rem, 4vw, 2.5rem);
}

.section-wrapper {
  padding: clamp(3.5rem, 8vw, 6.5rem) 0;
  position: relative;
}

/* ==========================================================================
   NAVIGATION BAR
   ========================================================================== */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  transition: all var(--transition-normal);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
}

.brand-icon {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, #FF7A30 0%, #F59E0B 100%);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 1.25rem;
  color: #080A0E;
  box-shadow: 0 4px 14px rgba(255, 122, 48, 0.4);
  transition: transform var(--transition-fast);
}

.brand-logo:hover .brand-icon {
  transform: rotate(5deg) scale(1.05);
}

.brand-text-wrap {
  display: flex;
  flex-direction: column;
}

.brand-name {
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.04em;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 4px;
}

.brand-name span {
  color: var(--accent-primary);
}

.brand-tagline-micro {
  font-size: 0.68rem;
  color: var(--text-muted);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  font-weight: 600;
}

/* Nav Links Desktop */
.nav-menu {
  display: flex;
  align-items: center;
  gap: 8px;
  list-style: none;
}

.nav-link {
  padding: 8px 16px;
  font-size: 0.93rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-full);
  transition: all var(--transition-fast);
  position: relative;
}

.nav-link:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
}

.nav-link.active {
  color: var(--text-primary);
  background: rgba(255, 122, 48, 0.12);
  border: 1px solid rgba(255, 122, 48, 0.28);
  font-weight: 600;
}

.nav-badge-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-primary);
  color: #080A0E;
  font-size: 0.7rem;
  font-weight: 700;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  margin-left: 6px;
}

/* Nav Actions Right */
.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.model-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.model-status-pill:hover {
  background: rgba(255, 255, 255, 0.07);
  border-color: rgba(255, 255, 255, 0.15);
  color: var(--text-primary);
}

.status-dot-pulse {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #10B981;
  box-shadow: 0 0 8px #10B981;
  animation: pulse-dot 2s infinite ease-in-out;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.85); }
}

/* Mobile Hamburger Button */
.hamburger-btn {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-subtle);
}

.hamburger-line {
  width: 20px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.hamburger-btn.open .hamburger-line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.hamburger-btn.open .hamburger-line:nth-child(2) {
  opacity: 0;
}
.hamburger-btn.open .hamburger-line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile Drawer */
.mobile-nav-drawer {
  position: fixed;
  top: 76px;
  left: 0;
  width: 100%;
  height: calc(100vh - 76px);
  background: rgba(8, 10, 14, 0.96);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border-top: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  padding: 24px;
  gap: 16px;
  transform: translateY(-100%);
  opacity: 0;
  pointer-events: none;
  transition: all var(--transition-smooth);
  z-index: 99;
}

.mobile-nav-drawer.open {
  transform: translateY(0);
  opacity: 1;
  pointer-events: auto;
}

.mobile-nav-link {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-secondary);
  padding: 14px 18px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: space-between;
  border: 1px solid transparent;
}

.mobile-nav-link.active {
  color: var(--text-primary);
  background: rgba(255, 122, 48, 0.1);
  border-color: rgba(255, 122, 48, 0.25);
}

/* ==========================================================================
   BUTTONS & UI CONTROLS
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 26px;
  font-size: 0.96rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  transition: all var(--transition-normal);
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, #FF7A30 0%, #F59E0B 100%);
  color: #080A0E;
  box-shadow: 0 4px 18px rgba(255, 122, 48, 0.35);
}

.btn-primary:hover {
  background: linear-gradient(135deg, #FFA048 0%, #FBBF24 100%);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(255, 122, 48, 0.5);
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.09);
  border-color: rgba(255, 255, 255, 0.16);
  transform: translateY(-2px);
}

.btn-ghost {
  color: var(--text-muted);
  padding: 10px 18px;
}

.btn-ghost:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.04);
}

.btn-icon {
  width: 40px;
  height: 40px;
  padding: 0;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

/* ==========================================================================
   HERO SECTION
   ========================================================================== */
.hero-section {
  padding: clamp(3.5rem, 8vw, 7rem) 0 clamp(2rem, 5vw, 4rem);
  text-align: center;
  position: relative;
}

.hero-pill-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: rgba(255, 122, 48, 0.09);
  border: 1px solid rgba(255, 122, 48, 0.22);
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent-primary);
  margin-bottom: 24px;
}

.hero-pill-badge svg {
  width: 14px;
  height: 14px;
}

.hero-title {
  font-size: clamp(2.5rem, 6.5vw, 4.8rem);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.04em;
  max-width: 860px;
  margin: 0 auto 24px;
  color: var(--text-primary);
}

.hero-title .gradient-text {
  background: linear-gradient(135deg, #FFF4E5 30%, #FF7A30 80%, #F59E0B 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.35rem);
  color: var(--text-secondary);
  max-width: 660px;
  margin: 0 auto 36px;
  line-height: 1.6;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 48px;
}

/* Visual Equation Element */
.visual-equation-card {
  max-width: 720px;
  margin: 0 auto 52px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 24px 28px;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.visual-equation-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 20%;
  width: 60%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255, 122, 48, 0.4), transparent);
}

.equation-steps {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.eq-step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  flex: 1;
}

.eq-tag {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
}

.eq-tag.highlight {
  background: rgba(255, 122, 48, 0.15);
  border-color: rgba(255, 122, 48, 0.35);
  color: var(--accent-primary);
}

.eq-tag.output {
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.15), rgba(56, 189, 248, 0.15));
  border-color: rgba(16, 185, 129, 0.35);
  color: #34D399;
}

.eq-desc {
  font-size: 0.72rem;
  color: var(--text-muted);
}

.eq-arrow {
  color: var(--accent-primary);
  font-size: 1.1rem;
  font-weight: 700;
  opacity: 0.8;
}

/* Quick Natural Input Bar on Hero */
.hero-quick-input-box {
  max-width: 740px;
  margin: 0 auto;
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 12px 14px 12px 20px;
  display: flex;
  align-items: center;
  gap: 14px;
  box-shadow: var(--shadow-lg), 0 0 40px rgba(255, 122, 48, 0.08);
  transition: border-color var(--transition-normal), box-shadow var(--transition-normal);
}

.hero-quick-input-box:focus-within {
  border-color: var(--border-glow);
  box-shadow: var(--shadow-lg), var(--shadow-glow);
}

.quick-input-field {
  flex: 1;
  background: transparent;
  font-size: 0.98rem;
  color: var(--text-primary);
  line-height: 1.4;
}

.quick-input-field::placeholder {
  color: var(--text-faint);
  font-size: 0.92rem;
}

.quick-input-btn {
  background: var(--accent-primary);
  color: #080A0E;
  padding: 12px 22px;
  border-radius: var(--radius-md);
  font-weight: 700;
  font-size: 0.92rem;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.quick-input-btn:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.quick-examples {
  margin-top: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
  font-size: 0.78rem;
  color: var(--text-muted);
}

.quick-chip {
  padding: 4px 10px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.quick-chip:hover {
  background: rgba(255, 122, 48, 0.1);
  border-color: rgba(255, 122, 48, 0.25);
  color: var(--text-primary);
}

/* ==========================================================================
   PROBLEM SECTION
   ========================================================================== */
.problem-card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
  margin-top: 48px;
}

.problem-statement-banner {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent-primary);
  margin-bottom: 12px;
}

.section-heading {
  font-size: clamp(2rem, 4vw, 3rem);
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}

.section-subtext {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 620px;
  margin: 0 auto;
}

.feature-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.feature-box:hover {
  background: var(--bg-card-hover);
  border-color: rgba(255, 255, 255, 0.14);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.feature-box-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
}

.feature-box h3 {
  font-size: 1.25rem;
}

.feature-box p {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ==========================================================================
   PERSONALIZATION SECTION (Cards)
   ========================================================================== */
.personalization-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
  margin-top: 48px;
}

.param-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 24px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: all var(--transition-normal);
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.param-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-glow);
  box-shadow: 0 10px 28px rgba(0, 0, 0, 0.5), 0 0 20px rgba(255, 122, 48, 0.1);
}

.param-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}

.param-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  background: rgba(255, 122, 48, 0.1);
  color: var(--accent-primary);
  border: 1px solid rgba(255, 122, 48, 0.2);
}

.param-icon {
  font-size: 1.5rem;
}

.param-card h4 {
  font-size: 1.15rem;
  margin-bottom: 6px;
  color: var(--text-primary);
}

.param-card p {
  font-size: 0.88rem;
  color: var(--text-muted);
}

/* ==========================================================================
   BOREDOM METER COMPONENT
   ========================================================================== */
.boredom-meter-container {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 32px;
  max-width: 820px;
  margin: 60px auto 0;
  text-align: center;
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.boredom-title-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 24px;
}

.boredom-level-options {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  margin-bottom: 24px;
}

.boredom-option-btn {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px 12px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  transition: all var(--transition-fast);
}

.boredom-option-btn:hover {
  background: rgba(255, 255, 255, 0.07);
  border-color: rgba(255, 255, 255, 0.16);
  transform: translateY(-2px);
}

.boredom-option-btn.selected {
  background: rgba(255, 122, 48, 0.14);
  border-color: var(--accent-primary);
  box-shadow: 0 4px 18px rgba(255, 122, 48, 0.25);
}

.boredom-emoji {
  font-size: 1.8rem;
}

.boredom-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
}

.boredom-feedback-panel {
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  text-align: left;
}

.boredom-hint-text {
  font-size: 0.92rem;
  color: var(--text-secondary);
}

/* ==========================================================================
   OPEN-SOURCE AI SHOWCASE SECTION
   ========================================================================== */
.open-ai-section {
  background: linear-gradient(180deg, transparent 0%, rgba(16, 19, 26, 0.8) 50%, transparent 100%);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.open-ai-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
  margin-top: 48px;
}

.open-ai-story-content {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.open-ai-perk {
  display: flex;
  gap: 18px;
}

.perk-bullet-icon {
  width: 36px;
  height: 36px;
  min-width: 36px;
  border-radius: 50%;
  background: rgba(255, 122, 48, 0.12);
  border: 1px solid rgba(255, 122, 48, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-primary);
}

.perk-title {
  font-size: 1.08rem;
  font-weight: 700;
  margin-bottom: 4px;
  color: var(--text-primary);
}

.perk-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* Interactive Architecture Widget */
.architecture-card {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 32px;
  box-shadow: var(--shadow-lg);
  position: relative;
}

.arch-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border-subtle);
}

.arch-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  background: rgba(16, 185, 129, 0.15);
  color: #34D399;
  border: 1px solid rgba(16, 185, 129, 0.3);
}

.arch-pipeline-visual {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 24px;
}

.arch-node {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.9rem;
}

.arch-node.highlight-node {
  background: rgba(255, 122, 48, 0.12);
  border-color: rgba(255, 122, 48, 0.35);
  color: var(--text-primary);
}

.arch-connector {
  text-align: center;
  color: var(--accent-primary);
  font-weight: 700;
  font-size: 0.9rem;
  line-height: 1;
}

.model-switcher-box {
  background: rgba(0, 0, 0, 0.25);
  border-radius: var(--radius-md);
  padding: 16px;
  border: 1px solid var(--border-subtle);
}

.model-select-dropdown {
  width: 100%;
  background: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border-subtle);
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  cursor: pointer;
  margin-top: 8px;
}

/* ==========================================================================
   FOOTER
   ========================================================================== */
.site-footer {
  margin-top: auto;
  background: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  padding: 60px 0 32px;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 48px;
}

.footer-brand h3 {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 800;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.footer-brand h3 span {
  color: var(--accent-primary);
}

.footer-tagline {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-bottom: 16px;
  max-width: 320px;
}

.footer-open-ai-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  color: var(--text-muted);
}

.footer-col h4 {
  font-size: 0.9rem;
  font-family: var(--font-mono);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-primary);
  margin-bottom: 20px;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-links a {
  font-size: 0.92rem;
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: var(--accent-primary);
}

.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  color: var(--text-faint);
}

/* ==========================================================================
   PAGE VIEW SWITCHING
   ========================================================================== */
.view-container {
  display: none;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.3s ease, transform 0.3s ease;
}

.view-container.active-view {
  display: block;
  opacity: 1;
  transform: translateY(0);
}

/* ==========================================================================
   RESPONSIVE QUERIES
   ========================================================================== */
@media (max-width: 900px) {
  .nav-menu {
    display: none;
  }
  .hamburger-btn {
    display: flex;
  }
  .open-ai-grid {
    grid-template-columns: 1fr;
  }
  .footer-top {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .equation-steps {
    flex-direction: column;
    gap: 16px;
  }
  .eq-arrow {
    transform: rotate(90deg);
  }
  .boredom-level-options {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .hero-quick-input-box {
    flex-direction: column;
    align-items: stretch;
    padding: 16px;
  }
  .quick-input-btn {
    width: 100%;
    justify-content: center;
  }
  .boredom-feedback-panel {
    flex-direction: column;
    text-align: center;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }
}