/* ==========================================================================
   CSS VARIABLES — Design Tokens
   ========================================================================== */

:root {
  /* ---- Colors ---- */
  --color-primary:       #0a1628;
  --color-primary-light: #323e50;
  --color-primary-dark:  #000000;
  --color-accent:        #1565e8;
  --color-bg:            #ffffff;
  --color-bg-alt:        #f0f4ff;
  --color-text:          #4a5568;
  --color-text-muted:    #9aa5b8;
  --color-border:        #e5e7eb;
  --color-white:         #ffffff;
  --color-black:         #0a0a0a;

  /* ---- Typography ---- */
  --font-primary:  'Inter', system-ui, -apple-system, sans-serif;
  --font-secondary: 'Inter', serif;
  --font-mono:     'JetBrains Mono', 'Fira Code', monospace;

  --text-xs:   clamp(0.70rem, 0.5vw  + 0.60rem, 0.75rem);
  --text-sm:   clamp(0.85rem, 0.5vw  + 0.75rem, 0.90rem);
  --text-base: clamp(1.00rem, 0.5vw  + 0.85rem, 1.10rem);
  --text-md:   clamp(1.10rem, 1vw    + 0.90rem, 1.25rem);
  --text-lg:   clamp(1.20rem, 1.5vw  + 0.90rem, 1.50rem);
  --text-xl:   clamp(1.50rem, 2vw    + 1.00rem, 2.00rem);
  --text-2xl:  clamp(1.80rem, 3vw    + 1.00rem, 2.50rem);
  --text-3xl:  clamp(2.25rem, 4vw    + 1.00rem, 3.25rem);
  --text-4xl:  clamp(2.80rem, 5vw    + 1.00rem, 4.00rem);
  --text-5xl:  clamp(3.50rem, 6vw    + 1.00rem, 5.50rem);

  --weight-regular: 400;
  --weight-medium:  500;
  --weight-semibold: 600;
  --weight-bold:    700;
  --weight-black:   900;

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

  --tracking-tight:  -0.02em;
  --tracking-normal: 0;
  --tracking-wide:   0.05em;

  /* ---- Spacing ---- */
  --space-1:   0.25rem;    /*  4px */
  --space-2:   0.50rem;    /*  8px */
  --space-3:   0.75rem;    /* 12px */
  --space-4:   1.00rem;    /* 16px */
  --space-5:   1.25rem;    /* 20px */
  --space-6:   1.50rem;    /* 24px */
  --space-8:   2.00rem;    /* 32px */
  --space-10:  2.50rem;    /* 40px */
  --space-12:  3.00rem;    /* 48px */
  --space-16:  4.00rem;    /* 64px */
  --space-20:  5.00rem;    /* 80px */
  --space-24:  6.00rem;    /* 96px */
  --space-32:  8.00rem;    /* 128px */

  --section-padding-y: clamp(4rem, 8vw, 7rem);
  --section-padding-x: clamp(1.25rem, 5vw, 2.5rem);

  /* ---- Layout ---- */
  --container-max: 1280px;
  --container-padding: clamp(1rem, 4vw, 2rem);

  /* ---- Border radius ---- */
  --radius-sm:   0.25rem;
  --radius-md:   0.5rem;
  --radius-lg:   1rem;
  --radius-xl:   1.5rem;
  --radius-full: 9999px;

  /* ---- Shadows ---- */
  --shadow-sm:  0 1px 3px rgba(0, 0, 0, 0.08), 0 1px 2px rgba(0, 0, 0, 0.06);
  --shadow-md:  0 4px 16px rgba(0, 0, 0, 0.10), 0 2px 4px rgba(0, 0, 0, 0.06);
  --shadow-lg:  0 10px 40px rgba(0, 0, 0, 0.12), 0 4px 8px rgba(0, 0, 0, 0.06);
  --shadow-xl:  0 20px 60px rgba(0, 0, 0, 0.15);
  --shadow-color: 0 4px 20px rgba(10, 22, 40, 0.3);

  /* ---- Transitions ---- */
  --transition-fast:   150ms ease;
  --transition-base:   250ms ease;
  --transition-slow:   400ms ease;
  --transition-bounce: 400ms cubic-bezier(0.34, 1.56, 0.64, 1);

  /* ---- Z-index ---- */
  --z-base:    1;
  --z-dropdown: 100;
  --z-sticky:  200;
  --z-overlay: 300;
  --z-modal:   400;
  --z-toast:   500;
}

/* ==========================================================================
   RESET & BASE
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 100%;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  hanging-punctuation: first last;
}

body {
  min-height: 100dvh;
  font-family: var(--font-primary);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

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

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

p,
h1,
h2,
h3,
h4,
h5,
h6 {
  overflow-wrap: break-word;
}

ul[role="list"],
ol[role="list"] {
  list-style: none;
}

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

a:hover {
  color: var(--color-primary);
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* Accessibility: skip link */
.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  z-index: var(--z-toast);
  padding: 0.75rem 1.25rem;
  background: var(--color-primary);
  color: var(--color-white);
  border-radius: var(--radius-md);
  font-weight: var(--weight-semibold);
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 1rem;
}

/* ==========================================================================
   TYPOGRAPHY
   ========================================================================== */

h1, .h1 {
  font-size: var(--text-5xl);
  font-weight: var(--weight-black);
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
}

h2, .h2 {
  font-size: var(--text-4xl);
  font-weight: var(--weight-bold);
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
}

h3, .h3 {
  font-size: var(--text-2xl);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-snug);
}

h4, .h4 {
  font-size: var(--text-xl);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-snug);
}

h5, .h5 {
  font-size: var(--text-lg);
  font-weight: var(--weight-medium);
}

h6, .h6 {
  font-size: var(--text-md);
  font-weight: var(--weight-medium);
}

p {
  max-width: 70ch;
  line-height: var(--leading-relaxed);
}

strong, b {
  font-weight: var(--weight-semibold);
}

small {
  font-size: var(--text-sm);
}

blockquote {
  border-left: 4px solid var(--color-primary);
  padding-left: var(--space-6);
  font-style: italic;
  color: var(--color-text-muted);
}

/* ==========================================================================
   LAYOUT
   ========================================================================== */

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-padding);
}

.section-header {
  text-align: center;
  max-width: 720px;
  margin-inline: auto;
  margin-bottom: var(--space-12);
}

.section-title {
  font-size: var(--text-4xl);
  font-weight: var(--weight-bold);
  letter-spacing: var(--tracking-tight);
  color: var(--color-text);
  margin-bottom: var(--space-4);
}

.section-subtitle {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  line-height: var(--leading-relaxed);
}

/* ==========================================================================
   BUTTONS
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.875rem 2rem;
  font-size: var(--text-base);
  font-weight: var(--weight-semibold);
  line-height: 1;
  border: 2px solid transparent;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition:
    background-color var(--transition-base),
    color var(--transition-base),
    border-color var(--transition-base),
    box-shadow var(--transition-base),
    transform var(--transition-fast);
  white-space: nowrap;
  text-decoration: none;
  user-select: none;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

.btn--primary {
  background-color: var(--color-primary);
  color: var(--color-white);
  border-color: var(--color-primary);
}

.btn--primary:hover {
  background-color: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
  box-shadow: var(--shadow-color);
  color: var(--color-white);
}

.btn--secondary {
  background-color: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.btn--secondary:hover {
  background-color: var(--color-primary);
  color: var(--color-white);
}

.btn--ghost {
  background-color: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}

.btn--ghost:hover {
  background-color: var(--color-bg-alt);
  border-color: var(--color-text);
}

.btn--large {
  padding: 1.125rem 2.5rem;
  font-size: var(--text-md);
}

.btn--small {
  padding: 0.5rem 1.25rem;
  font-size: var(--text-sm);
}

.btn--full {
  width: 100%;
}

/* ==========================================================================
   FORMS
   ========================================================================== */

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

.form-label {
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--color-text);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: 0.875rem 1.125rem;
  font-size: var(--text-base);
  color: var(--color-text);
  background-color: var(--color-bg);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  transition:
    border-color var(--transition-fast),
    box-shadow var(--transition-fast);
  appearance: none;
}

.form-input:hover,
.form-textarea:hover {
  border-color: var(--color-text-muted);
}

.form-input:focus,
.form-textarea:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(var(--color-primary-rgb, 0, 102, 255), 0.15);
  outline: none;
}

.form-textarea {
  resize: vertical;
  min-height: 140px;
}

.form-input::placeholder,
.form-textarea::placeholder {
  color: var(--color-text-muted);
  opacity: 0.7;
}

/* ==========================================================================
   SITE HEADER & NAVIGATION
   ========================================================================== */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-sticky);
  background-color: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: box-shadow var(--transition-base);
}

.site-header.scrolled {
  box-shadow: var(--shadow-sm);
}

.site-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4rem;
  gap: var(--space-8);
}

.site-logo {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  font-weight: var(--weight-bold);
  font-size: var(--text-lg);
  color: var(--color-text);
}

.site-logo:hover {
  color: var(--color-primary);
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-8);
  list-style: none;
}

.nav-menu a {
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
  position: relative;
}

.nav-menu a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-primary);
  transition: width var(--transition-base);
}

.nav-menu a:hover {
  color: var(--color-primary);
}

.nav-menu a:hover::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 2rem;
  height: 2rem;
  align-items: center;
  justify-content: center;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle__bar {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-text);
  transition: transform var(--transition-base), opacity var(--transition-fast);
  border-radius: var(--radius-full);
}

/* ==========================================================================
   CONTACT
   ========================================================================== */

.contact {
  padding-block: var(--section-padding-y);
  background-color: var(--color-bg);
}

.contact__layout {
  display: grid;
  grid-template-columns: 1fr 1.5fr;
  gap: var(--space-16);
  align-items: start;
}

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

.contact__info {
  display: flex;
  flex-direction: column;
  gap: var(--space-8);
}

/* ==========================================================================
   FOOTER
   ========================================================================== */

.site-footer {
  background-color: var(--color-text);
  color: rgba(255, 255, 255, 0.7);
  padding-block: var(--space-16) var(--space-8);
}

.footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}

.site-footer .site-logo {
  color: var(--color-white);
  margin-bottom: var(--space-4);
  display: inline-block;
}

.footer__tagline {
  font-size: var(--text-sm);
  line-height: var(--leading-relaxed);
  max-width: 40ch;
}

.footer__nav-title {
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  color: var(--color-white);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
  margin-bottom: var(--space-4);
}

.footer__nav ul {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  list-style: none;
}

.footer__nav a {
  font-size: var(--text-sm);
  color: rgba(255, 255, 255, 0.65);
  transition: color var(--transition-fast);
}

.footer__nav a:hover {
  color: var(--color-white);
}

.footer__bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--space-6);
  text-align: center;
}

.footer__copyright {
  font-size: var(--text-xs);
  max-width: none;
}

/* ==========================================================================
   UTILITIES
   ========================================================================== */

/* Visually hidden (accessible) */
.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;
}

/* Text alignment */
.text-center { text-align: center; }
.text-left   { text-align: left; }
.text-right  { text-align: right; }

/* Display */
.hidden { display: none; }

/* GSAP animation base states */
.will-animate {
  opacity: 0;
  transform: translateY(20px);
}

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

/* ==========================================================================
   ANIMATIONS (pure CSS fallbacks — GSAP overrides when loaded)
   ========================================================================== */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(2rem);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-2rem);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@media (prefers-reduced-motion: no-preference) {
  .animate-fade-up {
    animation: fadeInUp 0.7s ease both;
  }

  .animate-fade-in {
    animation: fadeIn 0.5s ease both;
  }
}

@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;
  }
}

/* ==========================================================================
   RESPONSIVE — Mobile-first breakpoints
   ========================================================================== */

/* Tablet: 768px+ */
@media (max-width: 768px) {
  .hero--split-right .container,
  .hero--split-left .container {
    grid-template-columns: 1fr;
  }

  .hero--split-left .hero__media {
    order: 0;
  }

  .hero__actions {
    flex-direction: column;
    align-items: stretch;
  }

  .hero__actions .btn {
    text-align: center;
  }

  .features__grid,
  .benefits__grid {
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  }

  .about__layout,
  .contact__layout {
    grid-template-columns: 1fr;
  }

  .about__layout--reversed .about__media {
    order: 0;
  }

  .footer__grid {
    grid-template-columns: 1fr 1fr;
  }

  .footer__brand {
    grid-column: 1 / -1;
  }

  .nav-menu {
    display: none;
    position: fixed;
    inset: 4rem 0 0;
    background-color: var(--color-bg);
    flex-direction: column;
    align-items: stretch;
    padding: var(--space-8);
    gap: var(--space-6);
    border-top: 1px solid var(--color-border);
    overflow-y: auto;
  }

  .nav-menu.is-open {
    display: flex;
  }

  .nav-menu a {
    font-size: var(--text-lg);
    padding-block: var(--space-2);
  }

  .nav-toggle {
    display: flex;
  }
}

/* Mobile: 480px and below */
@media (max-width: 480px) {
  .footer__grid {
    grid-template-columns: 1fr;
  }

  .pricing__grid {
    grid-template-columns: 1fr;
  }

  .testimonials__grid {
    grid-template-columns: 1fr;
  }

  .stats__grid {
    grid-template-columns: 1fr 1fr;
  }

  .hero__title {
    font-size: var(--text-3xl);
  }

  .section-title {
    font-size: var(--text-3xl);
  }
}