/* =========================================
   1. VARIABLES & RESET
   ========================================= */
:root {
  /* Brand Colors */
  --color-primary: #0f172a;      /* Deep Slate */
  --color-secondary: #334155;    /* Muted Slate */
  --color-accent: #0ea5e9;       /* Sky Blue (Medical/Tech) */
  --color-accent-glow: rgba(14, 165, 233, 0.4);
  --color-bg: #f8fafc;           /* Very Light Grey/Blue */
  --color-surface: #ffffff;
  --color-text-main: #1e293b;
  --color-text-muted: #64748b;
  
  /* Gradients */
  --gradient-hero: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
  --gradient-text: linear-gradient(135deg, #0ea5e9 0%, #2563eb 100%);
  
  /* Shadows & Glass */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-glow: 0 0 20px var(--color-accent-glow);
  
  --glass-bg: rgba(255, 255, 255, 0.7);
  --glass-border: 1px solid rgba(255, 255, 255, 0.5);
  --blur-amt: 12px;

  /* Spacing */
  --container-width: 1200px;
  --header-height: 80px;
  
  /* Radius */
  --radius-sm: 0.5rem;
  --radius-md: 1rem;
  --radius-lg: 1.5rem;
  --radius-full: 9999px;
}

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

html {
  scroll-behavior: smooth;
  font-family: 'Plus Jakarta Sans', system-ui, -apple-system, sans-serif;
  color: var(--color-text-main);
  background-color: var(--color-bg);
  line-height: 1.6;
}

/* =========================================
   2. TYPOGRAPHY
   ========================================= */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -0.02em;
}

h1 {
  font-size: 3.5rem;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 1.5rem;
}

h2 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  color: var(--color-primary);
}

h3 {
  font-size: 1.5rem;
  margin-bottom: 0.75rem;
}

p {
  margin-bottom: 1.5rem;
  color: var(--color-text-muted);
  font-size: 1.125rem;
}

.text-center { text-align: center; }
.text-gradient {
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* =========================================
   3. COMPONENTS
   ========================================= */

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.875rem 2rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  cursor: pointer;
  font-size: 1rem;
}

.btn-primary {
  background: var(--color-accent);
  color: white;
  box-shadow: 0 4px 14px 0 rgba(14, 165, 233, 0.39);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(14, 165, 233, 0.23);
  filter: brightness(1.1);
}

.btn-secondary {
  background: white;
  color: var(--color-text-main);
  border: 1px solid #e2e8f0;
}

.btn-secondary:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* Glass Card */
.glass-card {
  background: var(--glass-bg);
  backdrop-filter: blur(var(--blur-amt));
  -webkit-backdrop-filter: blur(var(--blur-amt));
  border: var(--glass-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-md);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.glass-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

/* Navbar */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: 1000;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(0,0,0,0.05);
  display: flex;
  align-items: center;
  justify-content: center;
}

.nav-container {
  width: 100%;
  max-width: var(--container-width);
  padding: 0 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  font-weight: 800;
  font-size: 1.5rem;
  color: var(--color-primary);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-link {
  text-decoration: none;
  color: var(--color-text-main);
  font-weight: 500;
  transition: color 0.2s;
}

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

/* Section Layout */
section {
  padding: 6rem 1.5rem;
  position: relative;
  overflow: hidden;
}

.container {
  max-width: var(--container-width);
  margin: 0 auto;
  width: 100%;
}

/* =========================================
   4. SPECIFIC SECTIONS
   ========================================= */

/* Hero */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-hero);
  padding-top: var(--header-height);
  text-align: center;
}

.hero-content {
  max-width: 800px;
  position: relative;
  z-index: 10;
}

.hero-badges {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 2rem;
}

.badge {
  background: rgba(14, 165, 233, 0.1);
  color: var(--color-accent);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 600;
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 3rem;
}

.feature-icon {
  width: 3rem;
  height: 3rem;
  background: var(--color-accent);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  margin-bottom: 1.5rem;
  font-size: 1.5rem;
}

/* Interactive Demo / Screenshot Area */
.demo-stage {
  margin-top: 4rem;
  perspective: 1000px;
}

.app-screenshot {
  border-radius: 1rem;
  box-shadow: 0 20px 40px -10px rgba(0,0,0,0.2);
  border: 1px solid rgba(0,0,0,0.1);
  transform: rotateX(2deg);
  transition: transform 0.5s ease;
  width: 100%;
  max-width: 900px;
  margin: 0 auto;
  display: block;
}

.app-screenshot:hover {
  transform: rotateX(0deg) scale(1.02);
}

/* Footer */
.footer {
  background: var(--color-primary);
  color: white;
  padding: 4rem 1.5rem 2rem;
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer p { color: #94a3b8; }

/* Responsive */
@media (max-width: 768px) {
  h1 { font-size: 2.5rem; }
  h2 { font-size: 2rem; }
  .nav-links { display: none; } /* Simplified mobile for now */
  .footer-content { flex-direction: column; gap: 2rem; text-align: center; }
}