/* ========================================
   SkyLife Labs — Static Site Styles
   Light, clean, minimal design
   ======================================== */

/* --- Self-hosted Inter font (SIL Open Font License) --- */
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 300 700;
  font-display: swap;
  src: url(fonts/inter-latin.woff2) format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD;
}

@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 300 700;
  font-display: swap;
  src: url(fonts/inter-latin-ext.woff2) format('woff2');
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF;
}

/* --- Custom Properties --- */
:root {
  --color-primary: #2563EB;
  --color-primary-hover: #1D4ED8;
  --color-primary-light: #EFF6FF;
  --color-text: #1E293B;
  --color-text-secondary: #64748B;
  --color-text-muted: #94A3B8;
  --color-bg: #FFFFFF;
  --color-bg-alt: #F8FAFC;
  --color-border: #E2E8F0;
  --color-border-light: #F1F5F9;

  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  --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: 1.5rem;
  --font-size-3xl: 2rem;
  --font-size-4xl: 2.75rem;

  --spacing-xs: 0.5rem;
  --spacing-sm: 0.75rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  --spacing-4xl: 6rem;

  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.07), 0 2px 4px -2px rgba(0,0,0,0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -4px rgba(0,0,0,0.04);

  --header-height: 64px;
  --max-width: 1080px;

  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 24px);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

ul {
  list-style: none;
}

/* --- Layout --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.section {
  padding: var(--spacing-4xl) 0;
}

.section:nth-child(even) {
  background-color: var(--color-bg-alt);
}

/* --- Header --- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--header-height);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border-light);
  transition: box-shadow var(--transition-base);
}

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

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

/* --- Logo --- */
.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  color: var(--color-text);
  font-weight: 600;
  font-size: var(--font-size-lg);
  text-decoration: none;
}

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

.logo-img {
  height: 32px;
  width: auto;
  flex-shrink: 0;
}

/* --- Navigation --- */
.nav-list {
  display: flex;
  gap: var(--spacing-xl);
}

.nav-link {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  font-weight: 500;
  letter-spacing: 0.01em;
  padding: var(--spacing-xs) 0;
  position: relative;
  text-decoration: none;
}

.nav-link:hover {
  color: var(--color-text);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-primary);
  border-radius: 1px;
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

.nav-link:hover::after {
  transform: scaleX(1);
}

/* Mobile nav toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}

.nav-toggle-bar {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-text);
  border-radius: 1px;
  transition: all var(--transition-base);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-family: var(--font-family);
  font-size: var(--font-size-sm);
  font-weight: 600;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition-fast);
  letter-spacing: 0.01em;
}

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

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

/* --- Hero --- */
.hero {
  padding-top: calc(var(--header-height) + var(--spacing-4xl));
  padding-bottom: var(--spacing-4xl);
  min-height: 70vh;
  display: flex;
  align-items: center;
}

.hero-content {
  max-width: 640px;
}

.hero-title {
  font-size: var(--font-size-4xl);
  font-weight: 700;
  line-height: 1.15;
  color: var(--color-text);
  margin-bottom: var(--spacing-lg);
  letter-spacing: -0.02em;
}

.hero-subtitle {
  font-size: var(--font-size-xl);
  color: var(--color-text-secondary);
  line-height: 1.6;
  margin-bottom: var(--spacing-2xl);
  max-width: 520px;
}

/* --- Section Titles --- */
.section-title {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--spacing-sm);
}

.section-intro {
  color: var(--color-text-secondary);
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-3xl);
}

/* --- Services Grid --- */
.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-xl);
}

.service-card {
  padding: var(--spacing-xl);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-bg);
}

.service-title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
}

.service-description {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* --- App Grid --- */
.app-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: var(--spacing-2xl);
}

/* --- App Card --- */
.app-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--spacing-2xl);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.app-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.app-card-header {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.app-icon-img {
  border-radius: var(--radius-md);
}

.app-name {
  font-size: var(--font-size-xl);
  font-weight: 700;
  line-height: 1.3;
}

.app-platform {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.app-description {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  line-height: 1.7;
  margin-bottom: var(--spacing-lg);
}

.app-features {
  margin-bottom: var(--spacing-xl);
  padding-left: 0;
}

.app-features li {
  position: relative;
  padding-left: var(--spacing-lg);
  margin-bottom: var(--spacing-xs);
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

.app-features li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 8px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-primary);
  opacity: 0.5;
}

.app-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-lg);
}

.store-badge {
  display: inline-block;
  transition: opacity var(--transition-fast), transform var(--transition-fast);
  border-radius: var(--radius-sm);
}

.store-badge:hover {
  opacity: 0.85;
  transform: translateY(-1px);
}

.app-links {
  display: flex;
  gap: var(--spacing-lg);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--color-border-light);
}

.app-links a {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
}

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

/* --- About --- */
.about-content {
  max-width: 640px;
}

.about-content p {
  color: var(--color-text-secondary);
  font-size: var(--font-size-lg);
  line-height: 1.8;
  margin-bottom: var(--spacing-lg);
}

.about-content p:last-child {
  margin-bottom: 0;
}

/* --- Contact --- */
.contact-content {
  text-align: center;
  max-width: 480px;
  margin: 0 auto;
}

.contact-content p {
  color: var(--color-text-secondary);
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-xl);
}

.contact-btn {
  padding: 14px 36px;
  font-size: var(--font-size-base);
}

/* --- Footer --- */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-xl) 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

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

.footer-nav {
  display: flex;
  gap: var(--spacing-lg);
}

.footer-nav a {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.footer-nav a:hover {
  color: var(--color-text-secondary);
}

/* ========================================
   Sub-pages (Privacy, Support, etc.)
   ======================================== */
.page-content {
  padding-top: calc(var(--header-height) + var(--spacing-3xl));
  padding-bottom: var(--spacing-4xl);
  min-height: 60vh;
}

.page-content h1 {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-bottom: var(--spacing-2xl);
  letter-spacing: -0.02em;
}

.page-content h2 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-top: var(--spacing-2xl);
  margin-bottom: var(--spacing-md);
}

.page-content h3 {
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-top: var(--spacing-xl);
  margin-bottom: var(--spacing-sm);
}

.page-content p,
.page-content li {
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: var(--spacing-md);
}

.page-content ul {
  padding-left: var(--spacing-xl);
  list-style: disc;
}

.page-content a {
  text-decoration: underline;
  text-underline-offset: 2px;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--spacing-xl);
  text-decoration: none;
}

.back-link:hover {
  color: var(--color-primary);
}

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 768px) {
  :root {
    --font-size-4xl: 2rem;
    --font-size-3xl: 1.5rem;
    --spacing-4xl: 4rem;
  }

  .nav-toggle {
    display: flex;
  }

  .main-nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-lg);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
  }

  .main-nav.open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-list {
    flex-direction: column;
    gap: 0;
  }

  .nav-link {
    display: block;
    padding: var(--spacing-md) 0;
    font-size: var(--font-size-base);
    border-bottom: 1px solid var(--color-border-light);
  }

  .nav-link:last-child {
    border-bottom: none;
  }

  .hero {
    min-height: auto;
    padding-top: calc(var(--header-height) + var(--spacing-3xl));
    padding-bottom: var(--spacing-3xl);
  }

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

  .app-card {
    padding: var(--spacing-xl);
  }

  .footer-inner {
    flex-direction: column;
    text-align: center;
  }

  .contact-content {
    text-align: left;
  }
}

@media (max-width: 480px) {
  :root {
    --font-size-4xl: 1.75rem;
    --spacing-4xl: 3rem;
  }

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

  .hero-subtitle {
    font-size: var(--font-size-base);
  }

  .app-actions {
    flex-direction: column;
  }

  .store-badge svg {
    width: 100%;
    max-width: 150px;
  }
}

/* --- Print --- */
@media print {
  .site-header,
  .nav-toggle,
  .store-badge {
    display: none;
  }

  .hero {
    padding-top: var(--spacing-xl);
    min-height: auto;
  }

  body {
    font-size: 12pt;
    color: #000;
  }
}