:root {
  /* --- 1. Primary Palette --- */
  --color-primary: #2563EB;
  --color-primary-dark: #1D4ED8;
  --color-primary-light: #EFF6FF;
  --color-navy: #1E3A5F;
  --color-green: #10B981;
  --color-red: #EF4444;
  --color-yellow: #F59E0B;
  --color-white: #FFFFFF;

  /* --- 2. Neutral Palette (Grayscale) --- */
  --gray-25: #FDFDFD;
  --gray-50: #F9FAFB;
  --gray-100: #F3F4F6;
  --gray-200: #E5E7EB;
  --gray-300: #D1D5DB;
  --gray-400: #9CA3AF;
  --gray-500: #6B7280;
  --gray-600: #4B5563;
  --gray-700: #374151;
  --gray-800: #1F2937;
  --gray-900: #111827;

  /* --- 3. Semantic Theme Variables (Light Mode) --- */
  --bg-body: var(--gray-50);
  --bg-card: var(--color-white);
  --bg-section-alt: var(--color-primary-light);
  --text-main: var(--gray-900);
  --text-muted: var(--gray-600);
  --text-heading: var(--color-navy);
  --border-main: var(--gray-200);
  --header-bg: rgba(255, 255, 255, 0.9);
  --footer-bg: var(--gray-900);
  --footer-text: var(--gray-400);

  /* --- 4. Typography --- */
  --font-family: 'Inter', system-ui, -apple-system, sans-serif;
  --font-size-xs: 0.75rem;   /* 12px */
  --font-size-sm: 0.875rem;  /* 14px */
  --font-size-base: 1rem;    /* 16px */
  --font-size-lg: 1.125rem;  /* 18px */
  --font-size-xl: 1.25rem;   /* 20px */
  --font-size-2xl: 1.5rem;   /* 24px */
  --font-size-3xl: 1.875rem; /* 30px */
  --font-size-4xl: 2.25rem;  /* 36px */
  --font-size-5xl: 3rem;     /* 48px */
  --font-size-6xl: 3.75rem;  /* 60px */

  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --font-weight-extrabold: 800;

  --line-height-base: 1.6;
  --line-height-tight: 1.25;

  /* --- 5. Spacing --- */
  --spacing-1: 0.25rem;
  --spacing-2: 0.5rem;
  --spacing-3: 0.75rem;
  --spacing-4: 1rem;
  --spacing-6: 1.5rem;
  --spacing-8: 2rem;
  --spacing-10: 2.5rem;
  --spacing-12: 3rem;
  --spacing-16: 4rem;
  --spacing-20: 5rem;

  /* --- 6. Effects (Shadows & Borders) --- */
  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-premium: 0 25px 50px -12px rgba(0, 0, 0, 0.15);

  --glass-bg: rgba(255, 255, 255, 0.7);
  --glass-border: rgba(255, 255, 255, 0.3);
  --glass-blur: blur(12px);

  /* --- 7. Gradient Variables --- */
  --hero-gradient: linear-gradient(135deg, var(--color-primary) 0%, var(--color-navy) 100%);
  --hero-gradient-red: linear-gradient(135deg, var(--color-red) 0%, #B91C1C 100%);
}

/* --- 7. Dark Mode --- */
body.dark-mode {
  --bg-body: #0B1120;
  --bg-card: #1E293B;
  --bg-section-alt: #1E293B;
  --text-main: #F8FAFC;
  --text-muted: #94A3B8;
  --text-heading: #F1F5F9;
  --border-main: #334155;
  --header-bg: rgba(15, 23, 42, 0.9);
  --footer-bg: #030712;
  --footer-text: #64748B;
  --color-primary-light: rgba(37, 99, 235, 0.15);

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.5);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.6);
  --glass-bg: rgba(30, 41, 59, 0.7);
  --glass-border: rgba(255, 255, 255, 0.1);
  --hero-gradient: linear-gradient(135deg, #60A5FA 0%, #3B82F6 100%);
  --hero-gradient-red: linear-gradient(135deg, #F87171 0%, #EF4444 100%);
}

/* --- 8. Base Styles --- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

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

h1, h2, h3, h4, h5, h6 {
  color: var(--text-heading);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
}

h1, h2 {
    text-shadow: 0 1px 2px rgba(0,0,0,0.02);
}

body.dark-mode h1, body.dark-mode h2 {
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

h1 { font-size: var(--font-size-4xl); margin-bottom: var(--spacing-6); letter-spacing: -0.025em; }
h2 { font-size: var(--font-size-3xl); margin-bottom: var(--spacing-4); }
h3 { font-size: var(--font-size-2xl); margin-bottom: var(--spacing-3); }
h4 { font-size: var(--font-size-xl); margin-bottom: var(--spacing-2); }

p { margin-bottom: var(--spacing-4); color: var(--text-muted); }

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: all 0.2s ease;
}

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

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

.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--spacing-6);
}

/* --- 9. Layout Utilities --- */
.text-center { text-align: center; }
.text-primary { color: var(--color-primary); }
.text-green { color: var(--color-green); }
.text-red { color: var(--color-red); }

.bg-white { background-color: var(--bg-card); }
.bg-gray-50 { background-color: var(--bg-body); }
.bg-primary-light { background-color: var(--bg-section-alt); }

.mb-4 { margin-bottom: var(--spacing-4); }
.mb-8 { margin-bottom: var(--spacing-8); }
.mt-4 { margin-top: var(--spacing-4); }
.mt-8 { margin-top: var(--spacing-8); }
.mt-12 { margin-top: var(--spacing-12); }
.py-12 { padding-top: var(--spacing-12); padding-bottom: var(--spacing-12); }
.pb-12 { padding-bottom: var(--spacing-12); }

.grid-responsive {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-6);
}

@media (min-width: 768px) {
  .grid-responsive { grid-template-columns: repeat(2, 1fr); gap: var(--spacing-8); }
}

@media (min-width: 1024px) {
  .grid-responsive { grid-template-columns: repeat(3, 1fr); gap: var(--spacing-10); }
}

/* --- 10. Components --- */

/* Hero Section */
.hero {
  background: radial-gradient(circle at top right, rgba(37, 99, 235, 0.15), transparent),
              linear-gradient(135deg, var(--color-navy) 0%, #0F172A 100%);
  color: var(--color-white);
  padding: 8rem 0 10rem 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 100px;
  background: linear-gradient(to top, var(--bg-body), transparent);
}

.hero h1 {
  font-size: var(--font-size-6xl);
  font-weight: var(--font-weight-extrabold);
  margin-bottom: var(--spacing-4);
}

.hero h1 span {
  background: linear-gradient(90deg, #60A5FA, #34D399);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: var(--font-size-xl);
  color: rgba(255, 255, 255, 0.85);
  max-width: 700px;
  margin: 0 auto;
}

.hero-search {
  max-width: 600px;
  margin: 4rem auto 0;
  position: relative;
  z-index: 10;
}

.hero-search input {
  width: 100%;
  padding: 1.25rem 1.5rem 1.25rem 3.5rem;
  border-radius: var(--radius-full);
  border: 1px dashed rgba(255, 255, 255, 0.1);
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(8px);
  color: white;
  font-size: var(--font-size-lg);
  box-shadow: var(--shadow-xl);
  transition: all 0.3s;
}

.hero-search input::placeholder { color: rgba(255, 255, 255, 0.5); }
.hero-search input:focus { background: rgba(255, 255, 255, 0.2); outline: none; border-color: var(--color-primary); }

.hero-search i {
  position: absolute;
  left: 1.5rem;
  top: 50%;
  transform: translateY(-50%);
  color: rgba(255, 255, 255, 0.6);
  font-size: 1.25rem;
}

/* Category Cards (Home Quick links) */
.quick-categories {
  max-width: 1100px;
  margin: -5rem auto 5rem;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  padding: 0 var(--spacing-6);
  position: relative;
  z-index: 20;
}

@media (min-width: 768px) {
  .quick-categories { grid-template-columns: repeat(4, 1fr); }
}

.category-card {
  background: var(--bg-card);
  border: 1px dashed var(--border-main);
  border-radius: var(--radius-lg);
  padding: 2rem;
  text-align: center;
  box-shadow: var(--shadow-lg);
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
}

.category-card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
  border-color: var(--color-primary);
}

.category-card i {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
  background: linear-gradient(135deg, var(--color-primary), #6366F1);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.category-card span {
  font-weight: var(--font-weight-bold);
  color: var(--text-heading);
  font-size: var(--font-size-lg);
}

/* Tool Cards */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.tool-card {
  background: var(--bg-card);
  border: 1px dashed var(--border-main);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  transition: all 0.3s;
  display: block;
}

.tool-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-primary);
  box-shadow: var(--shadow-md);
}

.tool-icon {
  width: 52px;
  height: 52px;
  background: var(--color-primary-light);
  color: var(--color-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1.25rem;
}

/* Cards & Sections */
.card {
  background: var(--bg-card);
  border: 1px dashed var(--border-main);
  border-radius: var(--radius-lg);
  padding: 2rem;
}

.glass {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  border: 1px dashed var(--glass-border);
}

/* How It Works */
.how-it-works {
  background: var(--bg-section-alt);
  padding: 6rem 0;
  margin: 6rem 0;
  border-radius: var(--radius-xl);
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(1, 1fr);
  gap: 2rem;
}

.step-item {
  text-align: center;
  padding: 2.5rem 2rem;
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  transition: all 0.3s;
}

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

.step-number {
  width: 50px;
  height: 50px;
  background: var(--color-primary);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1.5rem;
  margin: 0 auto 1.5rem;
  box-shadow: 0 4px 10px rgba(37, 99, 235, 0.3);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-md);
  font-weight: var(--font-weight-semibold);
  transition: all 0.3s;
  cursor: pointer;
  border: none;
}

.btn-primary { background: var(--color-primary); color: white; }
.btn-primary:hover { background: var(--color-primary-dark); transform: translateY(-2px); box-shadow: var(--shadow-md); }

.btn-outline { background: transparent; border: 2px dashed var(--color-primary); color: var(--color-primary); }
.btn-outline:hover { background: var(--color-primary); color: white; }

/* Responsive Overrides */
@media (max-width: 768px) {
  :root {
    --font-size-6xl: 2.75rem;
    --font-size-5xl: 2.25rem;
    --font-size-4xl: 1.875rem;
    --font-size-3xl: 1.5rem;
    --font-size-base: 0.9375rem;
  }

  .hero { padding: 5rem 0 7rem 0; }
  .quick-categories { margin-top: -4rem; }
  .steps-grid { grid-template-columns: 1fr; }
}

@media (min-width: 768px) {
  .steps-grid { grid-template-columns: repeat(3, 1fr); }
}


/* 404 Error Page Styles */
.error-section {
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 4rem 1rem;
}
.error-inner {
  max-width: 560px;
}
.error-code {
  font-size: 120px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-navy) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  margin-bottom: 0.5rem;
}
.error-inner h1 {
  font-size: var(--font-size-2xl);
  color: var(--color-navy);
  margin-bottom: 1rem;
}
.error-inner p {
  color: var(--color-gray-600);
  font-size: var(--font-size-lg);
  margin-bottom: 2rem;
  line-height: 1.7;
}
.error-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  margin-bottom: 3rem;
}
.popular-links h3 {
  font-size: var(--font-size-lg);
  color: var(--color-navy);
  margin-bottom: 1rem;
}
.quick-links {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem;
}
.quick-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.875rem 1rem;
  background: var(--color-gray-50);
  border: 1px solid var(--color-gray-100);
  border-radius: var(--radius-md);
  text-decoration: none;
  color: var(--color-gray-800);
  font-size: var(--font-size-sm);
  font-weight: 500;
  transition: all 0.2s;
}
.quick-link:hover {
  background: var(--color-primary-light);
  border-color: var(--color-primary);
  color: var(--color-primary);
}
.quick-link i {
  color: var(--color-primary);
}
@media (max-width: 480px) {
  .quick-links {
    grid-template-columns: 1fr;
  }
  .error-code {
    font-size: 80px;
  }
  .error-actions {
    flex-direction: column;
  }
}

/* 404 Error Page Styles */
@media (max-width: 1024px) {
    .main-footer, #footer-placeholder, #mainFooter {
        display: none !important;
    }
    body {
        padding-bottom: 70px !important;
    }
}

/* Import Responsive Layer (Last) */
@import url('responsive.css');