/* =========================================
   Global Variables & Base Styles
   ========================================= */

:root {
  /* Color Palette */
  --primary-color: #38bdf8; /* Sky Blue */
  --primary-hover: #0284c7;
  --text-main: #1d1d1f; /* Apple-like dark gray */
  --text-muted: #86868b;
  --bg-main: #ffffff;
  --bg-secondary: #f5f5f7; /* Apple-like off-white */
  --border-color: #e5e5ea;
  
  /* Typography */
  --font-family-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  
  /* Spacing */
  --spacing-xs: 0.5rem;   /* 8px */
  --spacing-sm: 1rem;     /* 16px */
  --spacing-md: 2rem;     /* 32px */
  --spacing-lg: 4rem;     /* 64px */
  --spacing-xl: 8rem;     /* 128px */
  
  /* Layout */
  --container-width-max: 1200px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  
  /* Transitions */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
}

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

body {
  font-family: var(--font-family-base);
  color: var(--text-main);
  background-color: var(--bg-main);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

ul {
  list-style: none;
}

/* =========================================
   Typography
   ========================================= */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.2;
}

h1 { font-size: 3rem; letter-spacing: -0.02em; }
h2 { font-size: 2.5rem; letter-spacing: -0.01em; margin-bottom: var(--spacing-sm); }
h3 { font-size: 1.5rem; margin-bottom: var(--spacing-sm); }
p { margin-bottom: var(--spacing-sm); }

.text-center { text-align: center; }
.text-muted { color: var(--text-muted); }

/* =========================================
   Layout & Containers
   ========================================= */
.container {
  width: 100%;
  max-width: var(--container-width-max);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

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

.section-bg-alt {
  background-color: var(--bg-secondary);
}

/* =========================================
   Components
   ========================================= */
/* Buttons */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: 9999px; /* Pill shape for modern look */
  font-weight: 500;
  text-align: center;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: 1px solid transparent;
}

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

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(56, 189, 248, 0.3);
}

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

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

/* Cards */
.card {
  background-color: #ffffff;
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.04);
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
  border: 1px solid var(--border-color);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08);
}

/* =========================================
   Header & Navigation
   ========================================= */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(12px); /* Glassmorphism effect */
  -webkit-backdrop-filter: blur(12px);
  z-index: 1000;
  border-bottom: 1px solid var(--border-color);
  transition: background-color var(--transition-fast);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 8px;
}

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

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

.nav-link {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-muted);
}

.nav-link:hover, .nav-link.active {
  color: var(--primary-color);
}

/* Mobile Menu Toggle */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.hamburger {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--text-main);
  position: relative;
  transition: background-color 0.3s;
}

.hamburger::before, .hamburger::after {
  content: '';
  position: absolute;
  width: 100%;
  height: 100%;
  background-color: var(--text-main);
  transition: transform 0.3s, top 0.3s, bottom 0.3s;
  left: 0;
}

.hamburger::before { top: -6px; }
.hamburger::after { bottom: -6px; }

.menu-toggle.is-active .hamburger {
  background-color: transparent;
}
.menu-toggle.is-active .hamburger::before {
  top: 0;
  transform: rotate(45deg);
}
.menu-toggle.is-active .hamburger::after {
  bottom: 0;
  transform: rotate(-45deg);
}

/* =========================================
   Footer
   ========================================= */
.site-footer {
  background-color: #111111; /* Dark aesthetic for footer */
  color: #ffffff;
  padding: var(--spacing-xl) 0 var(--spacing-md);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
}

.footer-col h4 {
  color: var(--primary-color);
  margin-bottom: var(--spacing-sm);
  font-size: 1.1rem;
}

.footer-col ul li {
  margin-bottom: 0.5rem;
}

.footer-col ul li a {
  color: #a1a1aa;
  font-size: 0.9rem;
}

.footer-col ul li a:hover {
  color: #ffffff;
}

.footer-bottom {
  border-top: 1px solid #333;
  padding-top: var(--spacing-md);
  text-align: center;
  color: #71717a;
  font-size: 0.85rem;
}

/* =========================================
   Animations
   ========================================= */
.fade-in-up {
  opacity: 0;
  transform: translateY(20px);
  animation: fadeInUp 0.8s ease forwards;
}

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

.delay-100 { animation-delay: 0.1s; }
.delay-200 { animation-delay: 0.2s; }
.delay-300 { animation-delay: 0.3s; }

/* =========================================
   Media Queries
   ========================================= */
@media (max-width: 768px) {
  :root {
    --spacing-xl: 4rem;
    --spacing-lg: 3rem;
  }
  
  h1 { font-size: 2.25rem; }
  h2 { font-size: 1.75rem; }
  
  .menu-toggle {
    display: block;
  }
  
  .nav-links {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 72px;
    left: 0;
    width: 100%;
    background-color: #ffffff;
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
    padding: var(--spacing-md);
    gap: var(--spacing-md);
    clip-path: circle(0% at top right);
    transition: clip-path 0.5s cubic-bezier(0.16, 1, 0.3, 1);
  }
  
  .nav-links.is-open {
    clip-path: circle(150% at top right);
  }
}