:root {
  --font-display: "Plus Jakarta Sans", "Inter", system-ui, sans-serif;
  --font-body: "Inter", system-ui, sans-serif;
  
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.75rem);
  
  --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;
  
  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-full: 9999px;
  
  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;
  
  --transition: 240ms cubic-bezier(0.16, 1, 0.3, 1);
}

/* NATIVE LIGHT THEME (DEFAULT) */
html[data-theme="light"],
html:not([data-theme="dark"]) {
  color-scheme: light;
  --color-bg: #f8f9fa;
  --color-bg-rgb: 248 249 250;
  --color-surface: #ffffff;
  --color-surface-2: #f1f3f5;
  --color-surface-offset: #e9ecef;
  --color-border: rgba(0, 0, 0, 0.06);
  --color-divider: rgba(0, 0, 0, 0.05);
  
  --color-text: #0b0b0d;
  --color-text-muted: #5e6472;
  --color-text-faint: #adb5bd;
  --color-text-inverse: #ffffff;
  
  --color-primary: #05c150;
  --color-primary-rgb: 5 193 80;
  --color-primary-hover: #04a945;
  --color-primary-active: #03903b;
  --color-primary-bg: rgba(5, 193, 80, 0.08);
  
  --color-purple: #8b5cf6;
  
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.02);
  --shadow-md: 0 12px 24px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 24px 48px rgba(0, 0, 0, 0.06);
  
  --nav-bg-rgb: 255 255 255;
  --nav-divider: rgba(0, 0, 0, 0.05);
  --nav-text: #0b0b0d;
  --nav-text-muted: #5e6472;
  --nav-hover-surface: #f1f3f5;
  
  --gradient-accent: linear-gradient(135deg, var(--color-primary) 0%, var(--color-purple) 100%);
  --hero-glow: radial-gradient(circle at 50% -20%, rgba(139, 92, 246, 0.05) 0%, rgba(5, 193, 80, 0.04) 50%, transparent 80%);
}

/* PREMIUM DARK THEME (ALTERNATIVE) */
html[data-theme="dark"] {
  color-scheme: dark;
  --color-bg: #070708;
  --color-bg-rgb: 7 7 8;
  --color-surface: #0d0d0f;
  --color-surface-2: #131316;
  --color-surface-offset: #1a1a1f;
  --color-border: rgba(255, 255, 255, 0.05);
  --color-divider: rgba(255, 255, 255, 0.04);
  
  --color-text: #f3f4f6;
  --color-text-muted: #9ca3af;
  --color-text-faint: #4b5563;
  --color-text-inverse: #070708;
  
  --color-primary: #00ff66;
  --color-primary-rgb: 0 255 102;
  --color-primary-hover: #00e65c;
  --color-primary-active: #00cc52;
  --color-primary-bg: rgba(0, 255, 102, 0.08);
  
  --color-purple: #a855f7;
  
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 12px 32px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 24px 64px rgba(0, 0, 0, 0.6);
  
  --nav-bg-rgb: 7 7 8;
  --nav-divider: rgba(255, 255, 255, 0.05);
  --nav-text: #f3f4f6;
  --nav-text-muted: #9ca3af;
  --nav-hover-surface: #131316;
  
  --gradient-accent: linear-gradient(135deg, var(--color-primary) 0%, var(--color-purple) 100%);
  --hero-glow: radial-gradient(circle at 50% -20%, rgba(168, 85, 247, 0.08) 0%, rgba(0, 255, 102, 0.06) 50%, transparent 80%);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  overflow-x: hidden;
  color: var(--color-text);
  background-color: var(--color-bg);
  font-family: var(--font-body);
  letter-spacing: -0.01em;
  transition: color var(--transition), background-color var(--transition);
}

::selection {
  background: rgb(var(--color-primary-rgb) / 0.2);
  color: var(--color-text);
}

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

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
select,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
  border: none;
  background: none;
}

:focus-visible {
  outline: 2px solid var(--color-purple);
  outline-offset: 3px;
}

.container {
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: clamp(var(--space-4), 5vw, var(--space-12));
}

/* ==========================================================================
   HEADER / NAVIGATION
   ========================================================================== */
.site-nav {
  position: fixed;
  top: 0;
  z-index: 100;
  width: 100%;
  backdrop-filter: blur(20px);
  color: var(--nav-text);
  background: rgb(var(--nav-bg-rgb) / 0.8);
  border-bottom: 1px solid var(--nav-divider);
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
}

.site-nav.scrolled {
  background: rgb(var(--nav-bg-rgb) / 0.95);
  box-shadow: var(--shadow-sm);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 80px;
  padding-block: var(--space-3);
  gap: var(--space-4);
}

.brand {
  display: inline-flex;
  align-items: center;
  flex: 0 0 auto;
}

.brand-logo {
  display: block;
  width: auto;
  height: 40px;
  object-fit: contain;
  mix-blend-mode: multiply;
  opacity: 0.95;
  transition: filter var(--transition);
}

/* invert light logo on dark mode */
html[data-theme="dark"] .brand-logo {
  filter: brightness(0) invert(1);
  mix-blend-mode: normal;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

/* ==========================================================================
   BUTTON SYSTEM
   ========================================================================== */
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.75rem var(--space-6);
  border-radius: var(--radius-full);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  transition: all var(--transition);
}

/* Default Light Mode buttons: black button. Default Dark Mode: neon green button */
.button-primary {
  color: var(--color-bg);
  background: var(--color-text);
  border: 1px solid var(--color-text);
}

html[data-theme="light"] .button-primary {
  color: #ffffff;
  background: #000000;
  border-color: #000000;
}

html[data-theme="dark"] .button-primary {
  color: #070708;
  background: var(--color-primary);
  border-color: var(--color-primary);
  box-shadow: 0 4px 20px rgb(var(--color-primary-rgb) / 0.15);
}

.button-primary:hover {
  transform: translateY(-2px);
}

html[data-theme="light"] .button-primary:hover {
  background: #212529;
  border-color: #212529;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
}

html[data-theme="dark"] .button-primary:hover {
  background: #00ff66;
  box-shadow: 0 8px 28px rgb(var(--color-primary-rgb) / 0.3);
}

.button-primary:active {
  transform: translateY(0);
}

.button-ghost {
  color: var(--color-text);
  background: transparent;
  border: 1px solid var(--color-border);
}

.button-ghost:hover {
  background: var(--color-surface-2);
  border-color: var(--color-text-faint);
  transform: translateY(-1px);
}

/* DISCREET THEME TOGGLE */
.theme-toggle {
  display: inline-grid;
  place-items: center;
  width: 40px;
  height: 40px;
  padding: 0;
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  background: transparent;
  transition: all var(--transition);
}

.theme-toggle:hover {
  color: var(--color-text);
  border-color: var(--color-text-faint);
  background: var(--color-surface-2);
  transform: rotate(15deg);
}

.theme-icon {
  width: 18px;
  height: 18px;
  transition: transform var(--transition);
}

.theme-icon-sun {
  display: none;
}

html[data-theme="dark"] .theme-icon-moon {
  display: none;
}

html[data-theme="dark"] .theme-icon-sun {
  display: block;
}

/* ==========================================================================
   HERO SECTION
   ========================================================================== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: clip;
  padding-top: 120px;
  padding-bottom: var(--space-16);
  background-image: var(--hero-glow);
}

.hero-glow {
  position: absolute;
  top: -10%;
  left: 50%;
  width: 1000px;
  height: 600px;
  background: radial-gradient(ellipse, rgba(139, 92, 246, 0.03) 0%, rgba(5, 193, 80, 0.02) 55%, transparent 80%);
  transform: translateX(-50%);
  pointer-events: none;
}

.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: clamp(40px, 8vw, 96px);
  align-items: center;
}

.hero-copy {
  padding-top: var(--space-4);
}

.hero-badge,
.section-label {
  display: inline-flex;
  align-items: center;
  margin: 0 0 var(--space-5);
  padding: 0.5rem 1rem;
  color: var(--color-primary);
  background: var(--color-primary-bg);
  border: 1px solid rgb(var(--color-primary-rgb) / 0.12);
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

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

.hero-badge::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
  animation: badge-pulse 1.8s ease-in-out infinite;
}

.hero h1 {
  margin: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: var(--text-2xl);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -0.03em;
  text-wrap: balance;
}

.hero h1 em {
  font-style: normal;
  background: linear-gradient(135deg, var(--color-purple) 20%, var(--color-primary) 80%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  max-width: 520px;
  margin: var(--space-5) 0 0;
  color: var(--color-text-muted);
  font-size: var(--text-base);
  line-height: 1.6;
  font-weight: 400;
}

/* HERO PROOF METRICS (INFINITEPAY NUMBERS LOOK) */
.hero-proof {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-4);
  margin-top: var(--space-10);
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-border);
}

.proof-item {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.proof-item strong {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 600;
  line-height: 1;
  color: var(--color-text);
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.proof-item span {
  color: var(--color-text-muted);
  font-size: var(--text-xs);
  line-height: 1.4;
  font-weight: 500;
}

/* ==========================================================================
   DIAGNOSTIC FORM CARD (PREMIUM PANEL)
   ========================================================================== */
.form-card {
  position: sticky;
  top: 120px;
  z-index: 10;
  padding: clamp(var(--space-6), 4vw, var(--space-8));
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  transition: border-color var(--transition), box-shadow var(--transition);
}

/* Subtle glowing accent line on top of form card */
.form-card::after {
  content: "";
  position: absolute;
  top: 0;
  left: 30px;
  right: 30px;
  height: 2px;
  background: var(--gradient-accent);
  border-radius: var(--radius-full);
}

.form-copy h2 {
  margin: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: -0.02em;
}

.form-copy p {
  margin: var(--space-2) 0 0;
  color: var(--color-text-muted);
  font-size: var(--text-xs);
  font-weight: 500;
}

.form-card form {
  display: grid;
  gap: var(--space-4);
  margin-top: var(--space-6);
}

.field-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-4);
}

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

.field span {
  color: var(--color-text-muted);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.field input {
  width: 100%;
  padding: 0.75rem var(--space-4);
  color: var(--color-text);
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: 500;
  transition: all var(--transition);
}

.field select {
  width: 100%;
  padding: 0.75rem var(--space-4);
  color: var(--color-text);
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: 500;
  transition: all var(--transition);
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%235e6472'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 1rem center;
  background-size: 1.1rem;
  padding-right: 2.5rem;
}

html[data-theme="dark"] .field select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%239ca3af'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'/%3E%3C/svg%3E");
}

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

.field input:focus,
.field select:focus {
  border-color: var(--color-purple);
  background: var(--color-surface);
  box-shadow: 0 0 0 4px rgb(139 92 246 / 0.1);
  outline: none;
}

.button-submit {
  width: 100%;
  min-height: 48px;
  font-size: var(--text-sm);
  color: #070708 !important;
  background: var(--color-primary) !important;
  border-color: var(--color-primary) !important;
  box-shadow: 0 4px 16px rgb(var(--color-primary-rgb) / 0.15) !important;
}

.button-submit:hover {
  background: var(--color-primary-hover) !important;
  box-shadow: 0 8px 24px rgb(var(--color-primary-rgb) / 0.25) !important;
  transform: translateY(-2px);
}

.whats-icon {
  width: 18px;
  height: 18px;
  flex: 0 0 auto;
}

.form-disclaimer {
  margin: 0;
  color: var(--color-text-faint);
  font-size: 11px;
  text-align: center;
}

.form-status {
  display: none;
}

.form-status:not(:empty) {
  display: block;
  margin-top: var(--space-4);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  font-size: var(--text-xs);
  font-weight: 600;
  text-align: center;
  line-height: 1.4;
  background: var(--color-primary-bg);
  border: 1px solid rgb(var(--color-primary-rgb) / 0.2);
  color: var(--color-primary);
}

/* ==========================================================================
   SYSTEM / SECTION STYLES
   ========================================================================== */
.system-section {
  padding-block: clamp(80px, 12vw, 120px);
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  transition: background-color var(--transition);
}

.system-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(48px, 8vw, 88px);
  align-items: start;
}

.section-label {
  align-self: start;
}

.system-section h2 {
  margin: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.section-intro,
.solution-copy {
  margin: var(--space-4) 0 0;
  color: var(--color-text-muted);
  font-size: var(--text-base);
  line-height: 1.6;
  font-weight: 400;
}

/* PROBLEM CARDS OVERHAUL (Sleek Dark Tiles) */
.problem-stack {
  display: grid;
  gap: var(--space-4);
  margin-top: var(--space-8);
}

.problem-intro {
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.problem-card {
  position: relative;
  padding: var(--space-5) var(--space-6);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition);
}

.problem-card:hover {
  transform: translateY(-2px);
  border-color: var(--color-text-faint);
  box-shadow: var(--shadow-md);
}

.problem-num {
  margin: 0 0 var(--space-2);
  color: var(--color-purple);
  font-family: var(--font-display);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.05em;
}

.problem-title {
  margin: 0;
  color: var(--color-text);
  font-size: var(--text-sm);
  font-weight: 500;
}

.problem-desc {
  margin: var(--space-2) 0 0;
  color: var(--color-text-muted);
  font-size: var(--text-xs);
  line-height: 1.5;
  font-weight: 500;
}

/* WHAT WE DELIVER / FEATURE LIST (InfinitePay checklist look) */
.system-right {
  display: flex;
  flex-direction: column;
}

.solution-title {
  margin: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.feature-list {
  display: grid;
  gap: var(--space-3);
  margin-top: var(--space-5);
}

.feature-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  color: var(--color-text);
  font-size: var(--text-sm);
  font-weight: 400;
}

.feature-dot {
  position: relative;
  width: 16px;
  height: 16px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--color-primary-bg);
  border: 1px solid rgb(var(--color-primary-rgb) / 0.2);
}

.feature-dot::after {
  position: absolute;
  inset: 4px;
  border-radius: 50%;
  background: var(--color-primary);
  content: "";
}

/* FLOW TIMELINE STEPS (InfinitePay Transaction Combo Look) */
.flow-card {
  margin-top: var(--space-8);
  overflow: hidden;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
}

.flow-step {
  display: flex;
  gap: var(--space-4);
  padding: var(--space-4) var(--space-5);
  transition: background-color var(--transition);
}

.flow-step:hover {
  background: var(--color-surface-2);
}

.flow-step + .flow-step {
  border-top: 1px solid var(--color-border);
}

.flow-step-num {
  min-width: 2.5rem;
  color: var(--color-purple);
  font-family: var(--font-display);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.05em;
}

.flow-step-name {
  color: var(--color-text);
  font-size: var(--text-xs);
  font-weight: 500;
}

.flow-step-detail {
  margin-top: var(--space-1);
  color: var(--color-text-muted);
  font-size: 11px;
  line-height: 1.5;
  font-weight: 500;
}

/* ==========================================================================
   CTA BANNER (InfinitePay Sleek Purple/Green Stripe)
   ========================================================================== */
.cta-banner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-6);
  margin-top: var(--space-16);
  padding: clamp(var(--space-6), 6vw, var(--space-10));
  background: linear-gradient(135deg, rgb(139 92 246 / 0.06) 0%, rgb(5 193 80 / 0.04) 100%);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
}

.cta-banner h3 {
  margin: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: -0.02em;
}

.cta-banner p {
  margin-top: var(--space-2);
  color: var(--color-text-muted);
  font-size: var(--text-xs);
  font-weight: 500;
  line-height: 1.5;
}

/* ==========================================================================
   FOOTER
   ========================================================================== */
.site-footer {
  padding-block: var(--space-8);
  border-top: 1px solid var(--color-border);
  background: var(--color-bg);
  transition: background-color var(--transition);
}

.footer-inner {
  color: var(--color-text-muted);
  font-size: var(--text-xs);
  text-align: center;
  font-weight: 500;
}

/* ==========================================================================
   MICRO ANIMATIONS / REVEALS
   ========================================================================== */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 800ms var(--transition), transform 800ms var(--transition);
}

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

@keyframes badge-pulse {
  0%, 100% {
    transform: scale(1);
    opacity: 1;
  }
  50% {
    transform: scale(1.3);
    opacity: 0.6;
  }
}

/* ==========================================================================
   MEDIA QUERIES (RESPONSIVENESS)
   ========================================================================== */
@media (max-width: 900px) {
  .hero-grid,
  .system-grid {
    grid-template-columns: 1fr;
    gap: var(--space-10);
  }

  .hero {
    min-height: auto;
    padding-top: 100px;
  }

  .hero-copy {
    padding-top: var(--space-4);
  }

  .form-card {
    position: static;
    margin-top: var(--space-4);
  }
}

@media (max-width: 640px) {
  .nav-inner {
    min-height: 72px;
  }

  .brand-logo {
    height: 32px;
  }

  .nav-ghost {
    display: none;
  }

  .field-row {
    grid-template-columns: 1fr;
    gap: var(--space-4);
  }

  .hero h1 {
    font-size: var(--text-xl);
  }

  .hero-proof {
    grid-template-columns: 1fr;
    gap: var(--space-3);
  }
  
  .proof-item {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
  
  .cta-banner {
    flex-direction: column;
    align-items: stretch;
    text-align: center;
  }
}