/* Base styles & Variables - Liquid Design
   =========================================
   WindowDrop Design System v2
   macOS-inspired palette with liquid theme
   ========================================= */
:root {
  color-scheme: light;
  /* ===========================================
     PRIMARY PALETTE
     macOS system blue, slightly warmer
     =========================================== */
  --color-primary: #007AFF;
  --color-primary-dark: #0055D4;
  --color-primary-light: #5AC8FA;
  --color-primary-subtle: #E3F2FD;

  /* ===========================================
     WARM ACCENT (for CTAs and highlights)
     Creates visual tension with blue
     =========================================== */
  --color-accent-warm: var(--color-primary);
  --color-accent-warm-dark: var(--color-primary-dark);
  --color-accent-warm-light: var(--color-primary-light);
  --color-accent-warm-subtle: var(--color-primary-subtle);

  /* ===========================================
     TEXT HIERARCHY
     Warm blacks, WCAG AA compliant
     =========================================== */
  --color-text: #1D1D1F;
  --color-text-secondary: #48484A;
  --color-text-muted: #86868B;
  --color-text-light: #AEAEB2;

  /* ===========================================
     BACKGROUNDS
     Layered surfaces for depth
     =========================================== */
  --color-bg: #FFFFFF;
  --color-bg-alt: #F5F5F7;
  --color-bg-elevated: #FFFFFF;
  --color-bg-inset: #EFEFF4;

  /* ===========================================
     BORDERS & DIVIDERS
     =========================================== */
  --color-border: #D2D2D7;
  --color-border-light: #E5E5EA;
  --color-border-focus: var(--color-primary);

  /* ===========================================
     SEMANTIC COLORS
     =========================================== */
  --color-success: #34C759;
  --color-success-subtle: #E8F9ED;
  --color-warning: #FF9500;
  --color-warning-subtle: #FFF8E6;
  --color-error: #FF3B30;
  --color-error-subtle: #FEE9E7;
  --color-info: #5AC8FA;
  --color-info-subtle: #E8F7FE;

  /* ===========================================
     GLASS-MORPHISM SYSTEM
     Improved for light backgrounds
     =========================================== */
  --glass-bg: rgba(248, 250, 252, 0.72);
  --glass-bg-hover: rgba(241, 245, 249, 0.85);
  --glass-bg-active: rgba(248, 250, 252, 0.92);

  --glass-border: rgba(148, 163, 184, 0.25);
  --glass-border-hover: rgba(148, 163, 184, 0.40);
  --glass-border-subtle: rgba(148, 163, 184, 0.12);

  --glass-shadow:
    0 1px 2px rgba(0, 0, 0, 0.04),
    0 4px 8px rgba(0, 0, 0, 0.04),
    0 8px 24px rgba(31, 38, 135, 0.08);
  --glass-shadow-hover:
    0 2px 4px rgba(0, 0, 0, 0.05),
    0 8px 16px rgba(0, 0, 0, 0.05),
    0 16px 48px rgba(31, 38, 135, 0.12);

  --glass-inner-glow: inset 0 1px 0 0 rgba(255, 255, 255, 0.6);
  --glass-inner-shadow: inset 0 -1px 0 0 rgba(0, 0, 0, 0.03);

  --glass-blur: blur(16px);
  --glass-blur-strong: blur(24px);
  --glass-blur-subtle: blur(8px);
  --glass-saturate: saturate(180%);
  --glass-filter: var(--glass-blur) var(--glass-saturate);
  
  /* Enhanced Liquid Color Palette */
  --liquid-deep: #1E40AF;           /* Deep ocean blue */
  --liquid-mid: #3B82F6;            /* Core blue */
  --liquid-bright: #60A5FA;         /* Bright water */
  --liquid-teal: #14B8A6;           /* Teal accent for depth */
  --liquid-aqua: #22D3EE;           /* Cyan highlight */
  --liquid-foam: #E0F2FE;           /* Foam white-blue */
  --liquid-shimmer: rgba(255, 255, 255, 0.7);  /* Light shimmer */

  /* Primary Liquid Gradients */
  --liquid-gradient-1: linear-gradient(
    135deg,
    var(--liquid-deep) 0%,
    var(--liquid-mid) 35%,
    var(--liquid-teal) 70%,
    var(--liquid-aqua) 100%
  );

  /* Ambient background gradients - more organic shapes */
  --liquid-gradient-2: radial-gradient(
    ellipse 80% 60% at 25% 40%,
    rgba(20, 184, 166, 0.25) 0%,
    rgba(59, 130, 246, 0.15) 40%,
    transparent 70%
  );
  --liquid-gradient-3: radial-gradient(
    ellipse 70% 80% at 75% 60%,
    rgba(34, 211, 238, 0.2) 0%,
    rgba(147, 197, 253, 0.12) 45%,
    transparent 75%
  );

  /* Additional ambient layers for depth */
  --liquid-gradient-foam: radial-gradient(
    ellipse 40% 30% at 50% 20%,
    rgba(224, 242, 254, 0.4) 0%,
    transparent 60%
  );
  --liquid-gradient-depth: linear-gradient(
    180deg,
    transparent 0%,
    rgba(30, 64, 175, 0.03) 50%,
    rgba(20, 184, 166, 0.05) 100%
  );

  /* Shimmer overlay for CTAs and highlights */
  --liquid-shimmer-gradient: linear-gradient(
    110deg,
    transparent 25%,
    rgba(255, 255, 255, 0.3) 50%,
    transparent 75%
  );

  /* Warm accent gradient for primary CTAs */
  --liquid-gradient-warm: linear-gradient(
    135deg,
    var(--color-accent-warm-dark) 0%,
    var(--color-accent-warm) 50%,
    var(--color-accent-warm-light) 100%
  );

  /* Mixed gradient for special emphasis */
  --liquid-gradient-mixed: linear-gradient(
    135deg,
    var(--color-primary) 0%,
    var(--liquid-teal) 50%,
    var(--color-accent-warm) 100%
  );

  /* Typography */
  --font-family:
    -apple-system, blinkmacsystemfont, "SF Pro Display", "SF Pro Text",
    system-ui, "Segoe UI", roboto, oxygen, ubuntu, cantarell,
    "Helvetica Neue", arial, sans-serif;
  --font-family-mono: "SF Mono", "Monaco", "Cascadia Code", "Roboto Mono", 
    "Courier New", monospace;

  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 2rem;
  --spacing-xl: 4rem;
  --spacing-2xl: 6rem;

  /* Layout */
  --max-width: 1200px;
  --max-width-narrow: 800px;
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  
  /* Animations */
  --animation-easing: cubic-bezier(0.34, 1.56, 0.64, 1);
  --animation-easing-smooth: cubic-bezier(0.4, 0, 0.2, 1);
  --animation-duration: 800ms;
  --animation-duration-fast: 200ms;
}

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

html {
  scroll-behavior: smooth;
}

/* Anchor scroll offset for sticky header - prevents content hiding under header */
[id] {
  scroll-margin-top: 5rem;
}

body {
  font-family: var(--font-family);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.7;
  font-size: 18px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  font-weight: 700;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 800;
}

h2 {
  font-size: clamp(2rem, 4vw, 3rem);
}

h3 {
  font-size: clamp(1.5rem, 3vw, 2rem);
}

p {
  margin-bottom: var(--spacing-md);
  max-width: 65ch;
}

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

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

ul, ol {
  padding-left: 1.5rem;
  margin-bottom: var(--spacing-md);
}

li {
  margin-bottom: var(--spacing-sm);
}

code {
  font-family: var(--font-family-mono);
  background: var(--color-bg-alt);
  padding: 0.2em 0.4em;
  border-radius: var(--radius-sm);
  font-size: 0.9em;
}

/* Utilities */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--spacing-md);
  padding-right: var(--spacing-md);
}

.container-narrow {
  max-width: var(--max-width-narrow);
}

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

/* Section notes and captions - centered by default (codebase-wide) */
.how-it-works-note,
.email-capture-privacy,
.download-hero-note,
.hero-animation-caption {
  text-align: center;
}

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

.text-gradient {
  background: linear-gradient(
    135deg,
    var(--liquid-deep) 0%,
    var(--liquid-mid) 30%,
    var(--liquid-teal) 65%,
    var(--liquid-aqua) 100%
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  background-size: 200% 200%;
}

/* Animated version for hero text */
.text-gradient-animated {
  background: linear-gradient(
    135deg,
    var(--liquid-deep) 0%,
    var(--liquid-mid) 30%,
    var(--liquid-teal) 65%,
    var(--liquid-aqua) 100%
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  background-size: 200% 200%;
  animation: textGradientFlow 5s ease-in-out infinite;
}

@keyframes textGradientFlow {
  0%, 100% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
}

/* Accessibility */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Focus styles - WCAG 2.1 visible focus requirement */
a:focus-visible,
button:focus-visible,
input:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  
  html {
    scroll-behavior: auto;
  }
}

/* Selection */
::selection {
  background-color: var(--color-primary-light);
  color: var(--color-text);
}