/* ========================================
   WalkTalk — Shared Foundation
   ======================================== */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: 'Nunito', sans-serif;
  font-weight: 400;
  font-size: 16px;
  line-height: 1.6;
  color: var(--on-surface);
  background-color: var(--surface);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

ul, ol {
  list-style: none;
}

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

/* --- Custom Properties --- */
:root {
  /* Brand colors */
  --primary: #7DA68A;
  --primary-light: #A8D5B4;
  --primary-dark: #5C8A6A;
  --secondary: #D4886C;
  --secondary-light: #FFB89E;
  --secondary-dark: #B06A50;
  --tertiary: #9B8DB5;
  --tertiary-light: #C4B8D8;

  /* Surfaces */
  --surface: #FAFAF7;
  --surface-dim: #F0EFE9;
  --surface-bright: #FFFFFF;
  --on-surface: #1C1B1F;
  --on-surface-variant: #49454F;
  --outline: #79747E;
  --outline-variant: #CAC4D0;

  /* Dark footer */
  --surface-dark: #1C1B1F;
  --on-surface-dark: #E6E1E5;
  --on-surface-dark-variant: #CAC4D0;

  /* Radii */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Spacing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  --space-4xl: 96px;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-nav: 0 2px 8px rgba(0, 0, 0, 0.08);

  /* Layout */
  --max-width: 1200px;
  --nav-height: 72px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 400ms ease;
}

/* --- Typography --- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  color: var(--on-surface);
}

h1 { font-size: 2.75rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }

p {
  color: var(--on-surface-variant);
  margin-bottom: 1em;
}

p:last-child {
  margin-bottom: 0;
}

.text-sm { font-size: 0.875rem; }
.text-lg { font-size: 1.125rem; }
.text-xl { font-size: 1.25rem; }

/* --- Container --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

/* --- Navigation --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--surface-bright);
  z-index: 1000;
  transition: box-shadow var(--transition-normal);
}

.nav.scrolled {
  box-shadow: var(--shadow-nav);
}

.nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

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

.nav-logo img {
  height: 44px;
  width: auto;
}

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

.nav-links a {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--on-surface-variant);
  transition: color var(--transition-fast);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  border-radius: 1px;
  transition: width var(--transition-normal);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--primary-dark);
}

.nav-links a.active::after {
  width: 100%;
}

.nav-cta {
  margin-left: var(--space-md);
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--space-sm);
  z-index: 1001;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--on-surface);
  border-radius: 2px;
  transition: transform var(--transition-normal), opacity var(--transition-fast);
}

.nav-open .hamburger span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-open .hamburger span:nth-child(2) {
  opacity: 0;
}

.nav-open .hamburger span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 12px 28px;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  transition: background var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
  white-space: nowrap;
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

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

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-dark);
}

.btn-secondary {
  background: var(--secondary);
  color: #fff;
}

.btn-secondary:hover {
  background: var(--secondary-dark);
}

.btn-outline {
  background: transparent;
  color: var(--primary-dark);
  border: 2px solid var(--primary);
}

.btn-outline:hover {
  background: var(--primary);
  color: #fff;
}

.btn-sm {
  padding: 8px 20px;
  font-size: 0.875rem;
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.0625rem;
}

/* --- Footer --- */
.footer {
  background: var(--surface-dark);
  color: var(--on-surface-dark);
  padding: var(--space-3xl) 0 var(--space-lg);
}

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

.footer-brand p {
  color: var(--on-surface-dark-variant);
  margin-top: var(--space-md);
  max-width: 320px;
}

.footer-brand .nav-logo img {
  height: 40px;
}

.footer h4 {
  color: var(--on-surface-dark);
  font-size: 0.9375rem;
  margin-bottom: var(--space-md);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.footer-links li {
  margin-bottom: var(--space-sm);
}

.footer-links a {
  color: var(--on-surface-dark-variant);
  font-size: 0.9375rem;
  transition: color var(--transition-fast);
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--space-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8125rem;
  color: var(--on-surface-dark-variant);
}

.footer-bottom-links {
  display: flex;
  gap: var(--space-lg);
}

.footer-bottom-links a {
  color: var(--on-surface-dark-variant);
  transition: color var(--transition-fast);
}

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

/* --- Section utility --- */
.section {
  padding: var(--space-4xl) 0;
}

.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto var(--space-3xl);
}

.section-header p {
  margin-top: var(--space-md);
  font-size: 1.125rem;
}

.section-label {
  display: inline-block;
  font-size: 0.8125rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--primary);
  margin-bottom: var(--space-sm);
}

/* --- Responsive --- */
@media (max-width: 1023px) {
  h1 { font-size: 2.25rem; }
  h2 { font-size: 1.75rem; }

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

  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 767px) {
  :root {
    --nav-height: 64px;
  }

  h1 { font-size: 1.875rem; }
  h2 { font-size: 1.5rem; }
  h3 { font-size: 1.25rem; }

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

  .section {
    padding: var(--space-3xl) 0;
  }

  /* Mobile nav */
  .hamburger {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: 0;
    width: 280px;
    height: 100vh;
    background: var(--surface-bright);
    flex-direction: column;
    align-items: flex-start;
    padding: calc(var(--nav-height) + var(--space-lg)) var(--space-lg) var(--space-lg);
    gap: var(--space-lg);
    transform: translateX(100%);
    transition: transform var(--transition-normal);
    box-shadow: var(--shadow-lg);
  }

  .nav-open .nav-links {
    transform: translateX(0);
  }

  .nav-cta {
    margin-left: 0;
    margin-top: var(--space-md);
  }

  /* Footer */
  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .footer-bottom {
    flex-direction: column;
    gap: var(--space-md);
    text-align: center;
  }
}

/* --- Overlay for mobile nav --- */
.nav-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  z-index: 999;
}

.nav-open .nav-overlay {
  display: block;
}

/* --- Reveal Animation --- */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

.reveal:nth-child(2) { transition-delay: 0.1s; }
.reveal:nth-child(3) { transition-delay: 0.2s; }