/*
 * @satellite
 * intent: Premium CSS design system for SEO Audit Tool SaaS
 * dependencies: Google Fonts (Plus Jakarta Sans, Space Grotesk)
 * pattern: Ethereal Glass — OLED black, mesh gradients, Double-Bezel cards
 * verified: false
 */

/* ============================================================
   0. FONT IMPORTS
   ============================================================ */
@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:ital,wght@0,300;0,400;0,500;0,600;0,700;0,800;1,400;1,500&family=Space+Grotesk:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

/* ============================================================
   1. CSS CUSTOM PROPERTIES — SEMANTIC DESIGN TOKENS
   ============================================================ */
:root {
  /* ---- Surface & Background ---- */
  --color-bg-deep:        #050505;
  --color-bg-primary:     #0a0a0a;
  --color-bg-elevated:    #111111;
  --color-bg-surface:     #161616;
  --color-bg-card:        #1a1a1a;
  --color-bg-card-inner:  #1e1e1e;

  /* ---- Brand Accent — Emerald/Cyan ---- */
  --color-primary:        #00e5a0;
  --color-primary-dim:    #00c589;
  --color-primary-glow:   rgba(0, 229, 160, 0.15);
  --color-primary-subtle: rgba(0, 229, 160, 0.08);

  /* ---- Secondary Accent — Electric Blue ---- */
  --color-secondary:      #3b82f6;
  --color-secondary-dim:  #2563eb;
  --color-secondary-glow: rgba(59, 130, 246, 0.12);

  /* ---- Semantic Status ---- */
  --color-success:        #22c55e;
  --color-warning:        #f59e0b;
  --color-error:          #ef4444;
  --color-info:           #06b6d4;

  /* ---- Text ---- */
  --color-text-primary:   #f5f5f5;
  --color-text-secondary: #a1a1aa;
  --color-text-tertiary:  #71717a;
  --color-text-muted:     #52525b;
  --color-text-inverse:   #050505;

  /* ---- Borders & Hairlines ---- */
  --color-border:         rgba(255, 255, 255, 0.06);
  --color-border-subtle:  rgba(255, 255, 255, 0.04);
  --color-border-strong:  rgba(255, 255, 255, 0.12);
  --color-border-accent:  rgba(0, 229, 160, 0.20);

  /* ---- Typography ---- */
  --font-display:  'Space Grotesk', system-ui, sans-serif;
  --font-body:     'Plus Jakarta Sans', system-ui, sans-serif;
  --font-mono:     'JetBrains Mono', 'SF Mono', monospace;

  --text-xs:    0.75rem;    /* 12px */
  --text-sm:    0.875rem;   /* 14px */
  --text-base:  1rem;       /* 16px */
  --text-lg:    1.125rem;   /* 18px */
  --text-xl:    1.25rem;    /* 20px */
  --text-2xl:   1.5rem;     /* 24px */
  --text-3xl:   1.875rem;   /* 30px */
  --text-4xl:   2.25rem;    /* 36px */
  --text-5xl:   3rem;       /* 48px */
  --text-6xl:   3.75rem;    /* 60px */
  --text-7xl:   4.5rem;     /* 72px */

  --leading-tight:   1.15;
  --leading-snug:    1.3;
  --leading-normal:  1.5;
  --leading-relaxed: 1.75;

  --tracking-tighter: -0.03em;
  --tracking-tight:   -0.02em;
  --tracking-normal:   0;
  --tracking-wide:     0.05em;
  --tracking-wider:    0.1em;
  --tracking-widest:   0.2em;

  /* ---- Spacing Scale ---- */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;
  --space-40: 10rem;

  /* ---- Radii ---- */
  --radius-sm:   0.5rem;
  --radius-md:   0.75rem;
  --radius-lg:   1rem;
  --radius-xl:   1.25rem;
  --radius-2xl:  1.5rem;
  --radius-3xl:  2rem;
  --radius-pill: 9999px;

  /* ---- Easing Curves ---- */
  --ease-out-expo:    cubic-bezier(0.23, 1, 0.32, 1);
  --ease-out-quint:   cubic-bezier(0.22, 1, 0.36, 1);
  --ease-spring:      cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-smooth:      cubic-bezier(0.4, 0, 0.2, 1);
  --ease-bounce:      cubic-bezier(0.68, -0.55, 0.265, 1.55);

  /* ---- Durations ---- */
  --dur-instant:  100ms;
  --dur-fast:     150ms;
  --dur-normal:   250ms;
  --dur-slow:     400ms;
  --dur-reveal:   600ms;
  --dur-dramatic: 800ms;

  /* ---- Shadows ---- */
  --shadow-sm:       0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md:       0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg:       0 8px 32px rgba(0, 0, 0, 0.5);
  --shadow-xl:       0 16px 48px rgba(0, 0, 0, 0.6);
  --shadow-glow:     0 0 40px var(--color-primary-glow);
  --shadow-inset:    inset 0 1px 1px rgba(255, 255, 255, 0.06);

  /* ---- Z-Index Layers ---- */
  --z-base:     1;
  --z-card:     10;
  --z-sticky:   100;
  --z-nav:      200;
  --z-overlay:  300;
  --z-modal:    400;
  --z-toast:    500;
}

/* ============================================================
   2. GLOBAL RESET & BASE STYLES
   ============================================================ */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: 400;
  line-height: var(--leading-normal);
  color: var(--color-text-primary);
  background-color: var(--color-bg-deep);
  min-height: 100dvh;
  overflow-x: hidden;
}

::selection {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}

img, video, svg {
  display: block;
  max-width: 100%;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease-out-expo);
}
a:hover {
  color: var(--color-primary-dim);
}

/* ============================================================
   3. LAYOUT CONTAINERS
   ============================================================ */
.container {
  width: 100%;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.container--wide {
  max-width: 1400px;
}

.container--narrow {
  max-width: 720px;
}

.section {
  padding-block: var(--space-24);
  position: relative;
}

.section--hero {
  padding-block: var(--space-16) var(--space-24);
  min-height: 100dvh;
  display: flex;
  align-items: center;
}

/* ============================================================
   4. TYPOGRAPHY CLASSES
   ============================================================ */
.heading-display {
  font-family: var(--font-display);
  font-size: var(--text-5xl);
  font-weight: 700;
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tighter);
  color: var(--color-text-primary);
}

.heading-1 {
  font-family: var(--font-display);
  font-size: var(--text-4xl);
  font-weight: 700;
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
}

.heading-2 {
  font-family: var(--font-display);
  font-size: var(--text-3xl);
  font-weight: 600;
  line-height: var(--leading-snug);
  letter-spacing: var(--tracking-tight);
}

.heading-3 {
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 600;
  line-height: var(--leading-snug);
}

.text-body {
  font-size: var(--text-base);
  line-height: var(--leading-relaxed);
  color: var(--color-text-secondary);
  max-width: 65ch;
}

.text-body-lg {
  font-size: var(--text-lg);
  line-height: var(--leading-relaxed);
  color: var(--color-text-secondary);
  max-width: 60ch;
}

.text-caption {
  font-size: var(--text-sm);
  color: var(--color-text-tertiary);
  line-height: var(--leading-normal);
}

.text-mono {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.02em;
}

/* ============================================================
   5. EYEBROW TAG / PILL BADGE
   ============================================================ */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-1) var(--space-3);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: var(--tracking-widest);
  color: var(--color-primary);
  background: var(--color-primary-subtle);
  border: 1px solid var(--color-border-accent);
  border-radius: var(--radius-pill);
  line-height: 1;
}

.eyebrow::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
  flex-shrink: 0;
}

/* ============================================================
   6. DOUBLE-BEZEL CARD SYSTEM
   ============================================================ */

/* -- Outer Shell -- */
.card {
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-2xl);
  padding: 6px;
  position: relative;
  transition:
    transform var(--dur-normal) var(--ease-out-expo),
    border-color var(--dur-normal) var(--ease-out-expo);
}

.card:hover {
  border-color: var(--color-border-strong);
  transform: translateY(-2px);
}

/* -- Inner Core -- */
.card__inner {
  background: var(--color-bg-card-inner);
  border-radius: calc(var(--radius-2xl) - 6px);
  padding: var(--space-6);
  box-shadow: var(--shadow-inset);
  position: relative;
  overflow: hidden;
}

/* Card variants */
.card--feature .card__inner {
  padding: var(--space-8);
}

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

.card--glow {
  box-shadow: var(--shadow-glow);
  border-color: var(--color-border-accent);
}

/* Card header inside inner */
.card__header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.card__icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--color-primary-subtle);
  border: 1px solid var(--color-border-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-xl);
  flex-shrink: 0;
}

.card__title {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--color-text-primary);
}

.card__description {
  font-size: var(--text-sm);
  color: var(--color-text-tertiary);
  line-height: var(--leading-relaxed);
}

/* ============================================================
   7. BUTTON SYSTEM — PILL + BUTTON-IN-BUTTON
   ============================================================ */

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  line-height: 1;
  border: none;
  cursor: pointer;
  border-radius: var(--radius-pill);
  transition:
    transform var(--dur-fast) var(--ease-out-expo),
    background-color var(--dur-normal) var(--ease-out-expo),
    box-shadow var(--dur-normal) var(--ease-out-expo);
  position: relative;
  white-space: nowrap;
  user-select: none;
}

.btn:active {
  transform: scale(0.97);
}

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

/* Primary Button */
.btn--primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
  padding: var(--space-3) var(--space-3) var(--space-3) var(--space-6);
  box-shadow: 0 0 20px var(--color-primary-glow);
}

.btn--primary:hover {
  background: var(--color-primary-dim);
  box-shadow: 0 0 30px var(--color-primary-glow);
}

/* Button trailing icon — "Button-in-Button" */
.btn__icon {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.15);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-base);
  transition: transform var(--dur-fast) var(--ease-out-expo);
  flex-shrink: 0;
}

.btn:hover .btn__icon {
  transform: translateX(2px) translateY(-1px) scale(1.05);
}

/* Secondary / Ghost Button */
.btn--secondary {
  background: transparent;
  color: var(--color-text-primary);
  padding: var(--space-3) var(--space-6);
  border: 1px solid var(--color-border-strong);
}

.btn--secondary:hover {
  background: rgba(255, 255, 255, 0.04);
  border-color: var(--color-text-tertiary);
}

/* Large Button */
.btn--lg {
  font-size: var(--text-base);
  padding: var(--space-4) var(--space-4) var(--space-4) var(--space-8);
}

.btn--lg .btn__icon {
  width: 40px;
  height: 40px;
  font-size: var(--text-lg);
}

/* ============================================================
   8. FORM INPUTS
   ============================================================ */
.input-group {
  position: relative;
  width: 100%;
}

.input {
  width: 100%;
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: 400;
  color: var(--color-text-primary);
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-4) var(--space-5);
  transition:
    border-color var(--dur-normal) var(--ease-out-expo),
    box-shadow var(--dur-normal) var(--ease-out-expo);
  outline: none;
}

.input::placeholder {
  color: var(--color-text-muted);
}

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

.input--with-btn {
  padding-right: calc(var(--space-4) + 140px);
}

/* Combo input + button */
.input-combo {
  position: relative;
  display: flex;
  align-items: center;
}

.input-combo .input {
  flex: 1;
  border-radius: var(--radius-2xl);
  padding: var(--space-5) var(--space-6);
  font-size: var(--text-lg);
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border-strong);
}

.input-combo .btn {
  position: absolute;
  right: 6px;
  top: 50%;
  transform: translateY(-50%);
}

.input-combo .btn:active {
  transform: translateY(-50%) scale(0.97);
}

/* ============================================================
   9. SCORE DISPLAY
   ============================================================ */
.score-ring {
  position: relative;
  width: 180px;
  height: 180px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.score-ring__svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.score-ring__track {
  fill: none;
  stroke: var(--color-border);
  stroke-width: 6;
}

.score-ring__fill {
  fill: none;
  stroke-width: 6;
  stroke-linecap: round;
  transition: stroke-dashoffset 1.2s var(--ease-out-expo);
}

.score-ring__value {
  font-family: var(--font-display);
  font-size: var(--text-5xl);
  font-weight: 700;
  letter-spacing: var(--tracking-tighter);
}

.score-ring__label {
  font-size: var(--text-sm);
  color: var(--color-text-tertiary);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wider);
}

/* Grade colors */
.grade-a { --grade-color: #22c55e; }
.grade-b { --grade-color: #84cc16; }
.grade-c { --grade-color: #f59e0b; }
.grade-d { --grade-color: #f97316; }
.grade-f { --grade-color: #ef4444; }

/* ============================================================
   10. RESULT ITEMS
   ============================================================ */
.result-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-4);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  transition: background var(--dur-fast) var(--ease-out-expo);
}

.result-item:hover {
  background: rgba(255, 255, 255, 0.02);
}

.result-item__status {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-sm);
  font-weight: 700;
  flex-shrink: 0;
  margin-top: 2px;
}

.result-item__status--pass {
  background: rgba(34, 197, 94, 0.15);
  color: var(--color-success);
}

.result-item__status--warn {
  background: rgba(245, 158, 11, 0.15);
  color: var(--color-warning);
}

.result-item__status--fail {
  background: rgba(239, 68, 68, 0.15);
  color: var(--color-error);
}

.result-item__content {
  flex: 1;
  min-width: 0;
}

.result-item__title {
  font-family: var(--font-display);
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: var(--space-1);
}

.result-item__desc {
  font-size: var(--text-sm);
  color: var(--color-text-tertiary);
  line-height: var(--leading-relaxed);
}

.result-item__value {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  background: var(--color-bg-surface);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  margin-top: var(--space-2);
  word-break: break-all;
  display: inline-block;
}

/* ============================================================
   11. FEATURE GRID
   ============================================================ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(1, 1fr);
  gap: var(--space-4);
}

/* ============================================================
   12. PRICING SECTION
   ============================================================ */
.pricing-card {
  text-align: center;
  max-width: 480px;
  margin-inline: auto;
}

.pricing-card .card__inner {
  padding: var(--space-10);
}

.price-tag {
  font-family: var(--font-display);
  font-size: var(--text-6xl);
  font-weight: 700;
  color: var(--color-text-primary);
  letter-spacing: var(--tracking-tighter);
  line-height: 1;
}

.price-tag__currency {
  font-size: var(--text-2xl);
  font-weight: 500;
  vertical-align: super;
  color: var(--color-text-secondary);
}

.price-tag__period {
  font-size: var(--text-base);
  font-weight: 400;
  color: var(--color-text-tertiary);
  display: block;
  margin-top: var(--space-2);
}

.pricing-features {
  list-style: none;
  text-align: left;
  margin-top: var(--space-8);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.pricing-features li {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.pricing-features li::before {
  content: '✓';
  color: var(--color-primary);
  font-weight: 700;
  font-size: var(--text-base);
  flex-shrink: 0;
}

/* ============================================================
   13. PAYMENT MODAL
   ============================================================ */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.8);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--dur-normal) var(--ease-out-expo);
  padding: var(--space-6);
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.modal {
  width: 100%;
  max-width: 460px;
  transform: translateY(20px) scale(0.96);
  transition: transform var(--dur-slow) var(--ease-out-expo);
}

.modal-overlay.active .modal {
  transform: translateY(0) scale(1);
}

.modal .card__inner {
  padding: var(--space-8);
}

.wallet-address {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-secondary);
  background: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-3) var(--space-4);
  word-break: break-all;
  cursor: pointer;
  transition: border-color var(--dur-fast) var(--ease-out-expo);
  position: relative;
}

.wallet-address:hover {
  border-color: var(--color-primary);
}

.wallet-address::after {
  content: 'Click to copy';
  position: absolute;
  right: var(--space-3);
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-body);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

/* ============================================================
   14. NAVIGATION
   ============================================================ */
.nav {
  position: fixed;
  top: var(--space-4);
  left: 50%;
  transform: translateX(-50%);
  z-index: var(--z-nav);
  background: rgba(10, 10, 10, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  padding: var(--space-2) var(--space-3);
  display: flex;
  align-items: center;
  gap: var(--space-1);
  max-width: calc(100vw - 2 * var(--space-6));
}

.nav__logo {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text-primary);
  padding: var(--space-2) var(--space-4);
  white-space: nowrap;
}

.nav__link {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-tertiary);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-pill);
  transition:
    color var(--dur-fast) var(--ease-out-expo),
    background var(--dur-fast) var(--ease-out-expo);
  white-space: nowrap;
}

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

/* ============================================================
   15. FOOTER
   ============================================================ */
.footer {
  border-top: 1px solid var(--color-border);
  padding-block: var(--space-12);
  text-align: center;
}

.footer__text {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* ============================================================
   16. MESH GRADIENT BACKGROUNDS
   ============================================================ */
.mesh-gradient {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  overflow: hidden;
}

.mesh-gradient::before,
.mesh-gradient::after {
  content: '';
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.4;
}

.mesh-gradient::before {
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(0, 229, 160, 0.12), transparent 70%);
  top: -15%;
  right: -10%;
}

.mesh-gradient::after {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.08), transparent 70%);
  bottom: 10%;
  left: -5%;
}

/* ============================================================
   17. ANIMATIONS & KEYFRAMES
   ============================================================ */

/* Fade-in-up base */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Fade-in scale */
@keyframes fadeInScale {
  from {
    opacity: 0;
    transform: scale(0.95);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

/* Pulse glow */
@keyframes pulseGlow {
  0%, 100% {
    box-shadow: 0 0 20px var(--color-primary-glow);
  }
  50% {
    box-shadow: 0 0 40px var(--color-primary-glow);
  }
}

/* Score ring fill animation */
@keyframes scoreReveal {
  from {
    stroke-dashoffset: 502;
  }
}

/* Shimmer for loading */
@keyframes shimmer {
  0% {
    transform: translateX(-100%);
  }
  100% {
    transform: translateX(100%);
  }
}

/* Stagger animation utility classes */
.animate-in {
  animation: fadeInUp var(--dur-reveal) var(--ease-out-expo) both;
}

.stagger-1  { animation-delay: 0ms; }
.stagger-2  { animation-delay: 50ms; }
.stagger-3  { animation-delay: 100ms; }
.stagger-4  { animation-delay: 150ms; }
.stagger-5  { animation-delay: 200ms; }
.stagger-6  { animation-delay: 250ms; }
.stagger-7  { animation-delay: 300ms; }
.stagger-8  { animation-delay: 350ms; }
.stagger-9  { animation-delay: 400ms; }
.stagger-10 { animation-delay: 450ms; }

/* Scroll-triggered reveal (use with IntersectionObserver) */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition:
    opacity var(--dur-reveal) var(--ease-out-expo),
    transform var(--dur-reveal) var(--ease-out-expo);
}

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

/* Loading skeleton */
.skeleton {
  position: relative;
  overflow: hidden;
  background: var(--color-bg-surface);
  border-radius: var(--radius-md);
}

.skeleton::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 255, 255, 0.04) 50%,
    transparent 100%
  );
  animation: shimmer 1.5s infinite;
}

/* ============================================================
   18. UTILITY CLASSES
   ============================================================ */
.text-center { text-align: center; }
.text-left   { text-align: left; }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }

.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

.mt-2 { margin-top: var(--space-2); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-10 { margin-top: var(--space-10); }
.mt-12 { margin-top: var(--space-12); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }

.mx-auto { margin-inline: auto; }
.w-full { width: 100%; }
.max-w-prose { max-width: 65ch; }

.hidden { display: none !important; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* ============================================================
   19. RESPONSIVE BREAKPOINTS
   ============================================================ */

/* Tablet: 768px+ */
@media (min-width: 768px) {
  .heading-display {
    font-size: var(--text-6xl);
  }

  .heading-1 {
    font-size: var(--text-5xl);
  }

  .heading-2 {
    font-size: var(--text-4xl);
  }

  .section {
    padding-block: var(--space-32);
  }

  .features-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-5);
  }

  .input-combo .input {
    font-size: var(--text-xl);
    padding: var(--space-6) var(--space-8);
  }

  .results-grid {
    grid-template-columns: 240px 1fr;
    gap: var(--space-8);
  }
}

/* Desktop: 1024px+ */
@media (min-width: 1024px) {
  .heading-display {
    font-size: var(--text-7xl);
  }

  .features-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-6);
  }

  .nav__link--mobile-hide {
    display: inline-flex;
  }
}

/* Wide: 1440px+ */
@media (min-width: 1440px) {
  .container {
    padding-inline: var(--space-8);
  }
}

/* Mobile: <768px specific */
@media (max-width: 767px) {
  .section {
    padding-block: var(--space-16);
  }

  .section--hero {
    padding-block: var(--space-12) var(--space-16);
  }

  .container {
    padding-inline: var(--space-4);
  }

  .nav {
    padding: var(--space-2);
  }

  .nav__link--mobile-hide {
    display: none;
  }

  .score-ring {
    width: 140px;
    height: 140px;
  }

  .score-ring__value {
    font-size: var(--text-4xl);
  }

  .results-grid {
    display: flex;
    flex-direction: column;
    gap: var(--space-6);
  }

  .pricing-card .card__inner {
    padding: var(--space-6);
  }

  .price-tag {
    font-size: var(--text-5xl);
  }

  .modal .card__inner {
    padding: var(--space-6);
  }
}

/* ============================================================
   20. REDUCED MOTION
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }

  .card:hover {
    transform: none;
  }

  .btn:active {
    transform: none;
  }
}

/* ============================================================
   21. RESULTS LAYOUT
   ============================================================ */
.results-grid {
  display: grid;
  gap: var(--space-6);
}

.results-sidebar {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-4);
}

.results-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

/* Divider */
.divider {
  height: 1px;
  background: var(--color-border);
  border: none;
  margin-block: var(--space-6);
}

/* Status bar */
.status-bar {
  height: 4px;
  border-radius: var(--radius-pill);
  background: var(--color-bg-surface);
  overflow: hidden;
  margin-top: var(--space-3);
}

.status-bar__fill {
  height: 100%;
  border-radius: var(--radius-pill);
  transition: width 1s var(--ease-out-expo);
}

/* ============================================================
   22. LOADING STATE
   ============================================================ */
.loading-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-6);
  padding: var(--space-16) 0;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ============================================================
   23. TOAST NOTIFICATION
   ============================================================ */
.toast {
  position: fixed;
  bottom: var(--space-6);
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  opacity: 0;
  z-index: var(--z-toast);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-pill);
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-primary);
  pointer-events: none;
  transition:
    opacity var(--dur-normal) var(--ease-out-expo),
    transform var(--dur-normal) var(--ease-out-expo);
  box-shadow: var(--shadow-lg);
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
  pointer-events: auto;
}