/* ══════════════════════════════════════════════════════════════
   llm-d ROI Calculator — Stylesheet
   Design system matched to llm-d Benchmark web app
   ══════════════════════════════════════════════════════════════ */

/* ── Design Tokens ── */
:root {
  /* Colors */
  --color-bg: #f7f8fc;
  --color-surface: #ffffff;
  --color-text: #1a202c;
  --color-text-secondary: #4a5568;
  --color-text-muted: #718096;
  --color-border: #e2e8f0;
  --color-border-light: #edf2f7;

  --color-rr: #e53e3e;
  --color-rr-dim: rgba(229, 62, 62, 0.08);
  --color-rr-glow: rgba(229, 62, 62, 0.15);
  --color-ca: #276749;
  --color-ca-bright: #38a169;
  --color-ca-dim: rgba(56, 161, 105, 0.08);
  --color-ca-glow: rgba(56, 161, 105, 0.15);
  --color-accent: #1f5fe6;
  --color-accent-dim: rgba(31, 95, 230, 0.08);
  --color-accent-glow: rgba(31, 95, 230, 0.18);
  --color-violet: #4b2fe0;
  --color-magenta: #8f2bd0;
  --color-pink: #ff3b6b;
  --color-highlight: #ecc94b;

  /* Family gradient spine (shared across hub demos) */
  --grad-family: linear-gradient(135deg, #1f5fe6 0%, #4b2fe0 35%, #8f2bd0 65%, #ff3b6b 100%);
  --grad-flow: linear-gradient(160deg, #1f5fe6, #4b2fe0, #8f2bd0, #ff3b6b, #8f2bd0, #4b2fe0, #1f5fe6);

  /* Typography */
  --font-display: 'Fraunces', Georgia, 'Times New Roman', serif;
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'SFMono-Regular', 'Consolas', 'Liberation Mono', 'Menlo', monospace;

  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.75rem;
  --font-size-3xl: 2.25rem;
  --font-size-hero: 5rem;

  /* 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;

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 300ms ease;
  --transition-smooth: 500ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.08);
  --shadow-xl: 0 12px 40px rgba(0,0,0,0.12);
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
::selection { background: rgba(75, 47, 224, 0.18); color: var(--color-text); }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  font-size: var(--font-size-base);
  line-height: 1.7;
  color: var(--color-text);
  background:
    radial-gradient(ellipse at 15% 50%, rgba(31,95,230,0.05) 0%, transparent 50%),
    radial-gradient(ellipse at 85% 20%, rgba(143,43,208,0.045) 0%, transparent 50%),
    radial-gradient(ellipse at 50% 90%, rgba(255,59,107,0.03) 0%, transparent 50%),
    var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Animated flowing gradient overlay — very slow, not distracting */
body::before {
  content: '';
  position: fixed;
  inset: -50%;
  background:
    radial-gradient(circle at 30% 40%, rgba(31,95,230,0.06) 0%, transparent 40%),
    radial-gradient(circle at 70% 60%, rgba(143,43,208,0.05) 0%, transparent 40%),
    radial-gradient(circle at 50% 30%, rgba(75,47,224,0.04) 0%, transparent 40%);
  animation: meshFloat 30s ease-in-out infinite;
  pointer-events: none;
  z-index: 0;
}

/* Noise texture overlay for premium grain feel */
body::after {
  content: '';
  position: fixed;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.03'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 256px 256px;
  pointer-events: none;
  z-index: 9998;
  opacity: 0.4;
}

@keyframes meshFloat {
  0%, 100% { transform: translate(0, 0) rotate(0deg); }
  33% { transform: translate(2%, -3%) rotate(1deg); }
  66% { transform: translate(-2%, 2%) rotate(-1deg); }
}

h1, h2, h3, h4 { font-family: var(--font-display); line-height: 1.3; }

a { color: var(--color-accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 var(--space-xl);
  position: relative;
  z-index: 1;
}

/* ── Scroll Progress Bar ── */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  background: var(--grad-family);
  z-index: 200;
  transition: width 50ms linear;
  border-radius: 0 2px 2px 0;
}

/* ── Sticky Header ── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(247, 248, 252, 0.72);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid rgba(0,0,0,0.06);
  box-shadow: 0 1px 3px rgba(0,0,0,0.02);
}

.header-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 var(--space-xl);
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header-brand {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

.header-logo {
  width: 28px;
  height: 28px;
  border-radius: 6px;
}

.header-title {
  font-family: var(--font-display);
  font-size: var(--font-size-lg);
  font-weight: 800;
  color: var(--color-text);
}

.header-subtitle {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  font-weight: 500;
  margin-left: var(--space-sm);
  display: none;
}

.header-actions { display: flex; gap: var(--space-sm); }

.btn-primary, .btn-outline {
  font-family: var(--font-display);
  font-size: var(--font-size-sm);
  font-weight: 600;
  padding: 8px 18px;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.btn-primary {
  background: var(--color-ca-bright);
  color: #fff;
  border: 1px solid var(--color-ca-bright);
}
.btn-primary:hover {
  background: var(--color-ca);
  border-color: var(--color-ca);
  text-decoration: none;
  transform: translateY(-1px);
  box-shadow: 0 4px 12px var(--color-ca-glow);
}

.btn-outline {
  background: transparent;
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
}
.btn-outline:hover {
  border-color: var(--color-text-muted);
  color: var(--color-text);
  text-decoration: none;
  transform: translateY(-1px);
}

/* ── Section Divider ── */
.section-divider {
  border: none;
  height: 1px;
  max-width: 1100px;
  margin: 0 auto;
  background: linear-gradient(90deg, transparent, rgba(31,95,230,0.25), rgba(143,43,208,0.22), transparent);
  position: relative;
  z-index: 1;
}

/* ── Scroll Reveal ── */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.visible { opacity: 1; transform: translateY(0); }
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }

/* ── Section Headers ── */
.section-title {
  font-family: var(--font-display);
  font-size: var(--font-size-3xl);
  font-weight: 900;
  letter-spacing: -0.5px;
  color: var(--color-text);
  margin-bottom: var(--space-sm);
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-violet) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-description {
  font-size: var(--font-size-lg);
  color: var(--color-text-secondary);
  max-width: 640px;
  margin-bottom: var(--space-2xl);
}

/* ══════════════════════════════════════════════════════════════
   HERO SECTION
   ══════════════════════════════════════════════════════════════ */
.hero {
  position: relative;
  z-index: 1;
  overflow: hidden;
  padding: var(--space-3xl) 0;
  text-align: center;
}

.hero::before,
.hero::after,
.hero-orb-accent {
  content: '';
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  pointer-events: none;
  z-index: 0;
}

.hero::before {
  width: 500px;
  height: 500px;
  top: -100px;
  right: -80px;
  border-radius: 40% 60% 55% 45% / 55% 45% 60% 40%;
  background: radial-gradient(circle, rgba(75, 47, 224, 0.18) 0%, transparent 70%);
  animation: floatOrb 12s ease-in-out infinite;
}

.hero::after {
  width: 400px;
  height: 400px;
  bottom: -60px;
  left: -60px;
  border-radius: 55% 45% 40% 60% / 45% 60% 40% 55%;
  background: radial-gradient(circle, rgba(31, 95, 230, 0.16) 0%, transparent 70%);
  animation: floatOrb 15s ease-in-out infinite -6s;
}

.hero-orb-accent {
  width: 350px;
  height: 350px;
  top: 50%;
  left: 60%;
  border-radius: 40% 60% 55% 45% / 55% 45% 60% 40%;
  background: radial-gradient(circle, rgba(255, 59, 107, 0.10) 0%, transparent 70%);
  animation: floatOrb 18s ease-in-out infinite -3s;
}

@keyframes floatOrb {
  0%, 100% { transform: translate(0, 0) scale(1); }
  25% { transform: translate(20px, -30px) scale(1.05); }
  50% { transform: translate(-15px, 15px) scale(0.95); }
  75% { transform: translate(25px, 20px) scale(1.03); }
}

.hero .container { position: relative; z-index: 1; }

.hero-tagline {
  display: block;
  font-family: var(--font-display);
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-md);
  letter-spacing: -0.2px;
}

.hero-number {
  display: block;
  font-family: var(--font-display);
  font-size: var(--font-size-hero);
  font-weight: 900;
  letter-spacing: -2px;
  line-height: 1.1;
  background: var(--grad-flow);
  background-size: 220% 220%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: gradientShift 8s ease-in-out infinite;
  margin-bottom: var(--space-sm);
}

@keyframes gradientShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

.hero-label {
  display: block;
  font-family: var(--font-display);
  font-size: var(--font-size-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--color-text-muted);
  margin-bottom: var(--space-2xl);
}

.hero-description {
  font-size: var(--font-size-lg);
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto var(--space-2xl);
  line-height: 1.7;
}

/* Hero Stat Cards */
.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
  max-width: 900px;
  margin: 0 auto;
}

.stat-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg) var(--space-lg) var(--space-md);
  text-align: center;
  position: relative;
  overflow: hidden;
  transition: all var(--transition-base);
  box-shadow:
    0 1px 2px rgba(0,0,0,0.02),
    0 4px 8px rgba(0,0,0,0.03),
    0 12px 32px rgba(0,0,0,0.05);
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--grad-family);
  opacity: 0.35;
  transition: opacity var(--transition-base);
}

.stat-card:hover {
  border-color: var(--color-accent);
  box-shadow:
    0 2px 4px rgba(0,0,0,0.02),
    0 8px 16px rgba(0,0,0,0.04),
    0 24px 48px rgba(0,0,0,0.06);
  transform: translateY(-6px);
}

.stat-card:hover::before { opacity: 1; }

.stat-value {
  font-family: var(--font-display);
  font-size: var(--font-size-2xl);
  font-weight: 900;
  color: var(--color-ca-bright);
  line-height: 1.2;
  margin-bottom: var(--space-xs);
}

/* Animated family-gradient accent on hero stat numbers */
.stat-card .stat-value {
  background: var(--grad-flow);
  background-size: 220% 220%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: gradientShift 8s ease-in-out infinite;
}

.stat-value--accent { color: var(--color-accent); }
.stat-value--green { color: var(--color-ca-bright); }

.stat-label {
  font-family: var(--font-display);
  font-size: var(--font-size-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--color-text-muted);
}

/* ══════════════════════════════════════════════════════════════
   CALCULATOR SECTION
   ══════════════════════════════════════════════════════════════ */
.calculator {
  position: relative;
  z-index: 1;
  padding: var(--space-3xl) 0;
}

.calculator-wrapper {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-2xl);
  position: relative;
  box-shadow:
    0 1px 2px rgba(0,0,0,0.02),
    0 4px 8px rgba(0,0,0,0.03),
    0 12px 32px rgba(0,0,0,0.05);
}

.calculator-wrapper::before {
  content: '';
  position: absolute;
  inset: -2px;
  border-radius: calc(var(--radius-xl) + 2px);
  padding: 2px;
  background: linear-gradient(135deg, rgba(31,95,230,0.55), rgba(143,43,208,0.4), rgba(255,59,107,0.45), rgba(31,95,230,0.55));
  background-size: 300% 300%;
  animation: borderGlow 6s ease-in-out infinite;
  /* Show only the 2px rim — mask out the interior so the card stays clean white. */
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  mask-composite: exclude;
  pointer-events: none;
}

@keyframes borderGlow {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

.calc-group {
  margin-bottom: var(--space-xl);
}

.calc-group:last-child { margin-bottom: 0; }

.calc-label {
  display: block;
  font-family: var(--font-display);
  font-size: var(--font-size-sm);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-sm);
  letter-spacing: 0.3px;
}

.calc-sublabel {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  font-weight: 400;
  margin-left: var(--space-sm);
}

/* Pill Buttons (Model Size / Workload Type) */
.calc-pills {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.calc-pill {
  font-family: var(--font-display);
  font-size: var(--font-size-sm);
  font-weight: 600;
  padding: 10px 22px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  background: var(--color-bg);
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
  user-select: none;
}

.calc-pill:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  transform: translateY(-1px);
}

.calc-pill:active { transform: scale(0.97); }

.calc-pill.active {
  background: linear-gradient(135deg, var(--color-accent), var(--color-magenta));
  color: #fff;
  border-color: transparent;
  box-shadow: 0 2px 12px var(--color-accent-glow);
}

/* GPU Type Cards */
.calc-gpu-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
}

.calc-gpu-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: var(--space-md) var(--space-lg);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.calc-gpu-card:hover {
  border-color: var(--color-accent);
  transform: translateY(-2px);
  box-shadow:
    0 2px 4px rgba(0,0,0,0.02),
    0 8px 16px rgba(0,0,0,0.04),
    0 24px 48px rgba(0,0,0,0.06);
}

.calc-gpu-card:active { transform: scale(0.97); }

.calc-gpu-card.active {
  border-color: var(--color-accent);
  background: var(--color-accent-dim);
  box-shadow: 0 4px 16px var(--color-accent-glow);
}

.calc-gpu-card.active::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--grad-family);
  opacity: 1;
}

.calc-gpu-card.active .gpu-name {
  color: var(--color-accent);
}

.gpu-name {
  font-family: var(--font-display);
  font-size: var(--font-size-sm);
  font-weight: 700;
  color: var(--color-text);
}

.gpu-cost {
  font-family: var(--font-mono);
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

.gpu-yearly {
  font-size: 10px;
  color: var(--color-text-muted);
  opacity: 0.7;
}

/* Range Slider */
.calc-slider-wrapper {
  position: relative;
  padding: var(--space-md) 0 var(--space-lg);
}

.calc-slider-value {
  text-align: center;
  font-family: var(--font-display);
  font-size: var(--font-size-2xl);
  font-weight: 800;
  background: var(--grad-family);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-md);
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 8px;
  border-radius: 4px;
  background: var(--color-border);
  outline: none;
  cursor: pointer;
  position: relative;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--color-surface);
  border: 3px solid var(--color-violet);
  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
  cursor: pointer;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.15);
  box-shadow: 0 3px 12px var(--color-accent-glow);
}

input[type="range"]::-webkit-slider-thumb:active {
  transform: scale(1.05);
}

input[type="range"]::-moz-range-thumb {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--color-surface);
  border: 3px solid var(--color-violet);
  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
  cursor: pointer;
}

.calc-slider-ticks {
  display: flex;
  justify-content: space-between;
  margin-top: var(--space-sm);
  font-family: var(--font-mono);
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

/* Custom Input Fields */
.calc-custom-input-row {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-top: var(--space-md);
}

.calc-custom-input-row label {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  font-weight: 500;
  white-space: nowrap;
}

.calc-custom-input {
  font-family: var(--font-mono);
  font-size: var(--font-size-sm);
  padding: 8px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg);
  color: var(--color-text);
  width: 160px;
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.calc-custom-input:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-glow);
}

.calc-custom-input::-webkit-inner-spin-button,
.calc-custom-input::-webkit-outer-spin-button {
  opacity: 1;
}

/* Advanced Options */
.calc-advanced { margin-top: var(--space-lg); }

.calc-advanced-toggle {
  font-family: var(--font-display);
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-text-muted);
  background: none;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) 0;
  transition: color var(--transition-fast);
}

.calc-advanced-toggle:hover { color: var(--color-text); }

.toggle-chevron {
  font-size: 10px;
  transition: transform var(--transition-base);
}

.calc-advanced-toggle.open .toggle-chevron {
  transform: rotate(180deg);
}

.calc-advanced-body {
  display: none;
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-border-light);
  margin-top: var(--space-md);
}

.calc-advanced-body.open { display: block; }

/* ══════════════════════════════════════════════════════════════
   GPU GRID COMPARISON
   ══════════════════════════════════════════════════════════════ */
.gpu-comparison {
  position: relative;
  z-index: 1;
  padding: var(--space-3xl) 0;
}

.gpu-comparison-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: var(--space-xl);
  align-items: start;
}

.gpu-panel {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow:
    0 1px 2px rgba(0,0,0,0.02),
    0 4px 8px rgba(0,0,0,0.03),
    0 12px 32px rgba(0,0,0,0.05);
  transition: box-shadow var(--transition-base);
}

.gpu-panel:hover {
  box-shadow:
    0 2px 4px rgba(0,0,0,0.02),
    0 8px 16px rgba(0,0,0,0.04),
    0 24px 48px rgba(0,0,0,0.06);
}

.gpu-panel--rr { border-top: 4px solid var(--color-rr); color: var(--color-rr); }
.gpu-panel--ca { border-top: 4px solid var(--color-ca-bright); color: var(--color-ca-bright); }

.gpu-panel-header h3,
.gpu-panel-stats .stat-label,
.gpu-count { color: var(--color-text); }

.gpu-panel-header {
  padding: var(--space-lg) var(--space-xl);
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--color-border-light);
}

.gpu-panel-header h3 {
  font-family: var(--font-display);
  font-size: var(--font-size-lg);
  font-weight: 800;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.comparison-label {
  font-size: var(--font-size-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  padding: 3px 10px;
  border-radius: var(--radius-full);
}

.comparison-label--rr {
  background: var(--color-rr-dim);
  color: var(--color-rr);
}

.comparison-label--ca {
  background: var(--color-ca-dim);
  color: var(--color-ca-bright);
}

.gpu-count {
  font-family: var(--font-display);
  font-size: var(--font-size-xl);
  font-weight: 900;
  color: var(--color-text);
  padding: var(--space-md) var(--space-xl) 0;
}

.gpu-grid {
  display: grid;
  gap: 8px;
  padding: var(--space-xl);
  min-height: 120px;
  align-content: start;
}

.gpu-icon {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  animation: gpuAppear 0.4s cubic-bezier(0.4, 0, 0.2, 1) both;
}

@keyframes gpuAppear {
  from { opacity: 0; transform: scale(0.5); }
  to { opacity: 1; transform: scale(1); }
}

.gpu-icon--saved {
  opacity: 0.25;
}

.gpu-saved-badge {
  font-family: var(--font-display);
  font-size: 7px;
  font-weight: 700;
  color: var(--color-ca-bright);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  animation: fadeIn 0.3s ease 0.4s both;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.gpu-grid-note {
  grid-column: 1 / -1;
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  text-align: center;
  padding-top: var(--space-sm);
}

.gpu-panel-stats {
  padding: var(--space-md) var(--space-xl) var(--space-lg);
  border-top: 1px solid var(--color-border-light);
}

.gpu-stat {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: var(--font-size-sm);
}

.gpu-stat span:first-child {
  color: var(--color-text-muted);
  font-weight: 500;
}

.gpu-stat span:last-child {
  font-family: var(--font-display);
  font-weight: 800;
  color: var(--color-text);
}

/* VS Divider */
.gpu-vs-divider {
  display: flex;
  align-items: center;
  justify-content: center;
  padding-top: 80px;
}

.vs-badge {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: var(--grad-family);
  background-size: 200% 200%;
  animation: vsShift 8s ease-in-out infinite;
  color: #fff;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 900;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-lg);
  letter-spacing: 1px;
}

@keyframes vsShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

/* Savings Banner (between grids) */
.savings-banner {
  grid-column: 1 / -1;
  margin-top: var(--space-xl);
  background: linear-gradient(135deg, var(--color-accent-dim), rgba(143,43,208,0.07), rgba(255,59,107,0.06));
  border: 1px solid rgba(75, 47, 224, 0.15);
  border-radius: var(--radius-lg);
  padding: var(--space-lg) var(--space-xl);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xl);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.savings-banner::before {
  content: '';
  position: absolute;
  top: 0; left: -100%; width: 60%; height: 100%;
  background: linear-gradient(90deg, transparent, rgba(75,47,224,0.08), transparent);
  animation: savingsShimmer 4s ease-in-out infinite;
}

@keyframes savingsShimmer {
  0%, 60%, 100% { left: -100%; }
  40% { left: 150%; }
}

.savings-banner-number {
  font-family: var(--font-display);
  font-size: var(--font-size-3xl);
  font-weight: 900;
  background: var(--grad-flow);
  background-size: 220% 220%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: gradientShift 8s ease-in-out infinite;
}

.savings-banner-label {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  font-weight: 500;
}

/* ══════════════════════════════════════════════════════════════
   SCENARIO CARDS
   ══════════════════════════════════════════════════════════════ */
.scenarios {
  position: relative;
  z-index: 1;
  padding: var(--space-3xl) 0;
}

.scenarios-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
}

.scenario-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  cursor: pointer;
  transition: all var(--transition-base);
  box-shadow:
    0 1px 2px rgba(0,0,0,0.02),
    0 4px 8px rgba(0,0,0,0.03),
    0 12px 32px rgba(0,0,0,0.05);
  position: relative;
  overflow: hidden;
}

.scenario-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--grad-family);
  opacity: 0.35;
  transition: opacity var(--transition-base);
}

.scenario-card:hover {
  border-color: var(--color-accent);
  box-shadow:
    0 2px 4px rgba(0,0,0,0.02),
    0 8px 16px rgba(0,0,0,0.04),
    0 24px 48px rgba(0,0,0,0.06);
  transform: translateY(-6px);
}

.scenario-card:hover::before { opacity: 1; }
.scenario-card:active { transform: translateY(-2px) scale(0.99); }

.scenario-card.active {
  border-color: var(--color-accent);
  box-shadow: 0 4px 20px var(--color-accent-glow);
}

.scenario-card.active::before { opacity: 1; }

.scenario-icon {
  font-size: 2rem;
  margin-bottom: var(--space-md);
  display: block;
}

.scenario-card h3 {
  font-family: var(--font-display);
  font-size: var(--font-size-base);
  font-weight: 800;
  margin-bottom: var(--space-sm);
  color: var(--color-text);
}

.scenario-card p {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: 1.5;
  margin-bottom: var(--space-md);
}

.scenario-specs {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin-bottom: var(--space-md);
}

.scenario-spec {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 500;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background: var(--color-bg);
  color: var(--color-text-muted);
  border: 1px solid var(--color-border-light);
}

.scenario-benefit {
  font-family: var(--font-display);
  font-size: var(--font-size-xs);
  font-weight: 600;
  color: var(--color-ca-bright);
  display: flex;
  align-items: center;
  gap: 4px;
}

/* ══════════════════════════════════════════════════════════════
   METHODOLOGY
   ══════════════════════════════════════════════════════════════ */
.methodology {
  position: relative;
  z-index: 1;
  padding: var(--space-3xl) 0;
}

.method-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-lg);
}

.method-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow:
    0 1px 2px rgba(0,0,0,0.02),
    0 4px 8px rgba(0,0,0,0.03),
    0 12px 32px rgba(0,0,0,0.05);
  transition: all var(--transition-base);
}

.method-item:hover {
  box-shadow:
    0 2px 4px rgba(0,0,0,0.02),
    0 8px 16px rgba(0,0,0,0.04),
    0 24px 48px rgba(0,0,0,0.06);
  transform: translateY(-2px);
}

.method-item[open] {
  border-color: var(--color-accent);
  box-shadow: 0 4px 16px var(--color-accent-glow);
}

.method-item summary {
  font-family: var(--font-display);
  font-size: var(--font-size-sm);
  font-weight: 700;
  color: var(--color-text);
  padding: var(--space-lg) var(--space-xl);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: background var(--transition-fast);
}

.method-item summary:hover {
  background: var(--color-bg);
}

.method-item summary::after {
  content: '+';
  font-size: var(--font-size-lg);
  font-weight: 300;
  color: var(--color-text-muted);
  transition: transform var(--transition-base);
}

.method-item[open] summary::after {
  transform: rotate(45deg);
}

.method-item-body {
  padding: 0 var(--space-xl) var(--space-lg);
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.method-item-body code {
  font-family: var(--font-mono);
  font-size: var(--font-size-xs);
  background: var(--color-bg);
  padding: 2px 6px;
  border-radius: 3px;
}

/* ══════════════════════════════════════════════════════════════
   FOOTER
   ══════════════════════════════════════════════════════════════ */
.site-footer {
  position: relative;
  z-index: 1;
  padding: var(--space-2xl) 0;
  text-align: center;
  border-top: 1px solid var(--color-border-light);
}

.footer-brand {
  font-family: var(--font-display);
  font-size: var(--font-size-sm);
  font-weight: 700;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: var(--space-xl);
  font-size: var(--font-size-sm);
}

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

.footer-note {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  margin-top: var(--space-md);
}

/* ══════════════════════════════════════════════════════════════
   RESPONSIVE
   ══════════════════════════════════════════════════════════════ */
@media (min-width: 769px) {
  .header-subtitle { display: inline; }
}

@media (max-width: 1024px) {
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .scenarios-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  :root {
    --font-size-hero: 3.5rem;
    --font-size-3xl: 1.75rem;
  }

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

  .hero { padding: var(--space-2xl) 0; }
  .hero-stats { grid-template-columns: 1fr 1fr; gap: var(--space-md); }

  .calculator-wrapper { padding: var(--space-lg); }
  .calc-gpu-cards { grid-template-columns: repeat(2, 1fr); }
  .calc-pills { flex-wrap: wrap; }

  .gpu-comparison-grid {
    grid-template-columns: 1fr;
  }
  .gpu-vs-divider {
    padding: 0;
    margin: var(--space-md) 0;
  }

  .scenarios-grid { grid-template-columns: 1fr; }
  .method-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  :root { --font-size-hero: 2.8rem; }
  .hero-stats { grid-template-columns: 1fr; }
  .header-actions { gap: 4px; }
  .btn-primary, .btn-outline { padding: 6px 12px; font-size: var(--font-size-xs); }
  .calc-custom-input-row { flex-wrap: wrap; }
  .calc-custom-input { width: 100%; max-width: 220px; }
}

/* ── Reduced Motion ── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    transition-delay: 0ms !important;
  }
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; }
  body::before { animation: none; }
}