/* NimbusCalc - Global Styles */
/* Design System: Precision Fluidity */

/* CSS Variables */
:root {
  /* Colors */
  --primary-purple: #7F56D9;
  --primary-purple-dark: #6D48B8;
  --primary-purple-light: #9B7FE8;
  --secondary-teal: #14B8A6;
  --secondary-teal-dark: #0D9488;
  --dark-bg: #0F172A;
  --dark-bg-light: #1E293B;
  --light-bg: #F8FAFC;
  --light-bg-alt: #F1F5F9;
  --text-dark: #1E293B;
  --text-light: #F1F5F9;
  --text-muted: #64748B;
  --accent-pink: #EC4899;
  --accent-blue: #3B82F6;
  --accent-green: #22C55E;
  --accent-orange: #F97316;
  --accent-red: #EF4444;
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, var(--primary-purple) 0%, var(--secondary-teal) 100%);
  --gradient-hero: linear-gradient(135deg, #0F172A 0%, #1E1B4B 50%, #0F172A 100%);
  --gradient-card: linear-gradient(145deg, rgba(127, 86, 217, 0.1) 0%, rgba(20, 184, 166, 0.1) 100%);
  
  /* Typography */
  --font-heading: 'Space Grotesk', sans-serif;
  --font-body: 'Inter', sans-serif;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  
  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;
  
  /* Shadows */
  --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 -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  --shadow-glow: 0 0 40px rgba(127, 86, 217, 0.3);
  
  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-base: 0.3s ease;
  --transition-slow: 0.5s ease;
  --transition-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --transition-expo: cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-body);
  background: var(--light-bg);
  color: var(--text-dark);
  line-height: 1.6;
  overflow-x: hidden;
  min-height: 100vh;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-dark);
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.5rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.75rem); }
h4 { font-size: clamp(1.1rem, 2vw, 1.25rem); }

p {
  color: var(--text-muted);
  font-size: 1rem;
}

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

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

/* Utility Classes */
.container {
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.container-narrow {
  max-width: 900px;
}

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

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-xl);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 1rem;
  border-radius: var(--radius-full);
  border: none;
  cursor: pointer;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
  transform: translateX(-100%);
  transition: transform 0.6s ease;
}

.btn:hover::before {
  transform: translateX(100%);
}

.btn-primary {
  background: var(--gradient-primary);
  color: white;
  box-shadow: 0 4px 15px rgba(127, 86, 217, 0.4);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(127, 86, 217, 0.5);
}

.btn-secondary {
  background: white;
  color: var(--primary-purple);
  border: 2px solid var(--primary-purple);
}

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

.btn-ghost {
  background: transparent;
  color: var(--text-dark);
}

.btn-ghost:hover {
  background: var(--light-bg-alt);
}

/* Navigation */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: var(--spacing-md) 0;
  transition: all var(--transition-base);
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(20px);
  box-shadow: var(--shadow-md);
  padding: var(--spacing-sm) 0;
}

.navbar-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-purple);
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: var(--gradient-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.25rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--spacing-xl);
  list-style: none;
}

.nav-links a {
  font-weight: 500;
  font-size: 0.95rem;
  position: relative;
  color: #17193D;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  transition: width var(--transition-base);
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-search {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);  /* 缩小间距，从 var(--spacing-md) 改为 var(--spacing-sm) */
}

.search-btn {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  background: var(--light-bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
}

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

/* ===== Navigation Icons (Favorite & Dashboard) ===== */
.nav-icon-btn {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1.3rem;
  padding: 8px;
  margin-left: 0;          /* 移除多余左边距，确保间距由父容器的 gap 控制 */
  transition: color 0.2s;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);           /* default gray (not saved) */
}
.nav-icon-btn:hover {
  color: var(--primary-purple);       /* hover color */
}
.nav-icon-btn[data-saved="1"] {
  color: var(--primary-purple);       /* saved state */
}
.nav-icon-btn i {
  pointer-events: none;
}
/* ===== END Navigation Icons ===== */

.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-sm);
}

.mobile-menu-btn span {
  width: 24px;
  height: 2px;
  background: var(--text-dark);
  transition: all var(--transition-fast);
}

/* Hero Section */
.hero {
  min-height: 100vh;
  background: var(--gradient-hero);
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 0 80px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image: 
    linear-gradient(rgba(127, 86, 217, 0.1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(127, 86, 217, 0.1) 1px, transparent 1px);
  background-size: 60px 60px;
  animation: gridMove 20s linear infinite;
}

@keyframes gridMove {
  0% { transform: translate(0, 0); }
  100% { transform: translate(60px, 60px); }
}

.hero-particles {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.particle {
  position: absolute;
  width: 4px;
  height: 4px;
  background: var(--primary-purple);
  border-radius: 50%;
  opacity: 0.5;
  animation: float 15s infinite ease-in-out;
}

@keyframes float {
  0%, 100% { transform: translateY(0) translateX(0); opacity: 0.3; }
  50% { transform: translateY(-100px) translateX(50px); opacity: 0.8; }
}

.hero-content {
  position: relative;
  z-index: 10;
  text-align: center;
  max-width: 800px;
  padding: 0 var(--spacing-lg);
}

.hero h1 {
  color: white;
  margin-bottom: var(--spacing-lg);
  animation: fadeInUp 0.8s var(--transition-expo) forwards;
  opacity: 0;
  transform: translateY(30px);
}

.hero p {
  color: rgba(255, 255, 255, 0.8);
  font-size: 1.25rem;
  margin-bottom: var(--spacing-2xl);
  animation: fadeInUp 0.8s var(--transition-expo) 0.2s forwards;
  opacity: 0;
  transform: translateY(30px);
}

.hero-buttons {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 0.8s var(--transition-expo) 0.4s forwards;
  opacity: 0;
  transform: translateY(30px);
}

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

/* Hero Stats */
.hero-stats {
  display: flex;
  justify-content: center;
  gap: var(--spacing-3xl);
  margin-top: var(--spacing-3xl);
  padding-top: var(--spacing-2xl);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  animation: fadeInUp 0.8s var(--transition-expo) 0.6s forwards;
  opacity: 0;
  transform: translateY(30px);
}

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

.stat-number {
  font-family: var(--font-heading);
  font-size: 2.5rem;
  font-weight: 700;
  color: white;
}

.stat-label {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* Section Styles */
.section {
  padding: var(--spacing-3xl) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--spacing-3xl);
}

.section-header h2 {
  margin-bottom: var(--spacing-md);
}

.section-header p {
  max-width: 600px;
  margin: 0 auto;
}

/* Category Cards */
.categories-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-lg);
}

.category-card {
  background: white;
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.category-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

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

.category-card:hover::before {
  transform: scaleX(1);
}

.category-icon {
  width: 60px;
  height: 60px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: var(--spacing-md);
}

.category-card h3 {
  margin-bottom: var(--spacing-sm);
}

.category-card p {
  font-size: 0.9rem;
  margin-bottom: var(--spacing-md);
}

.category-count {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  font-size: 0.875rem;
  color: var(--primary-purple);
  font-weight: 600;
}

/* Calculator Cards */
.calculators-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--spacing-lg);
}

.calculator-card {
  background: white;
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-md);
  border: 1px solid transparent;
}

.calculator-card:hover {
  border-color: var(--primary-purple-light);
  box-shadow: var(--shadow-lg);
  transform: translateY(-3px);
}

.calculator-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--gradient-card);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  flex-shrink: 0;
}

.calculator-info {
  flex: 1;
}

.calculator-info h4 {
  font-size: 1rem;
  margin-bottom: var(--spacing-xs);
}

.calculator-info p {
  font-size: 0.85rem;
  line-height: 1.4;
}

/* Calculator Page Styles */
.calculator-page {
  padding-top: 100px;
  min-height: 100vh;
  background: var(--light-bg);
}

.calculator-header {
  background: var(--gradient-hero);
  padding: var(--spacing-3xl) 0;
  margin-bottom: var(--spacing-2xl);
  position: relative;
  overflow: hidden;
}

.calculator-header::before {
  content: '';
  position: absolute;
  inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%237F56D9' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  opacity: 0.5;
}

.calculator-header-content {
  position: relative;
  z-index: 1;
  text-align: center;
}

.calculator-header h1 {
  color: white;
  margin-bottom: var(--spacing-md);
}

.calculator-header p {
  color: rgba(255, 255, 255, 0.8);
  max-width: 600px;
  margin: 0 auto;
}

.calculator-container {
  display: grid;
  grid-template-columns: 1fr 350px;
  gap: var(--spacing-xl);
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg) var(--spacing-3xl);
}

.calculator-main {
  background: white;
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-md);
}

.calculator-sidebar {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

.sidebar-widget {
  background: white;
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-md);
}

.sidebar-widget h4 {
  margin-bottom: var(--spacing-md);
  padding-bottom: var(--spacing-sm);
  border-bottom: 2px solid var(--light-bg-alt);
}

/* Form Styles */
.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
}

label {
  display: block;
  font-weight: 600;
  font-size: 0.9rem;
  margin-bottom: var(--spacing-sm);
  color: var(--text-dark);
}

label .optional {
  font-weight: 400;
  color: var(--text-muted);
  font-size: 0.8rem;
}

input[type="number"],
input[type="text"],
input[type="date"],
select,
textarea {
  width: 100%;
  padding: var(--spacing-md);
  border: 2px solid var(--light-bg-alt);
  border-radius: var(--radius-md);
  font-family: var(--font-body);
  font-size: 1rem;
  transition: all var(--transition-fast);
  background: white;
}

input[type="number"]:focus,
input[type="text"]:focus,
input[type="date"]:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: var(--primary-purple);
  box-shadow: 0 0 0 3px rgba(127, 86, 217, 0.1);
}

.input-group {
  display: flex;
  gap: var(--spacing-sm);
}

.input-group input,
.input-group select {
  flex: 1;
}

.input-group-addon {
  display: flex;
  align-items: center;
  padding: var(--spacing-md) var(--spacing-lg);
  background: var(--light-bg-alt);
  border: 2px solid var(--light-bg-alt);
  border-radius: var(--radius-md);
  font-weight: 600;
  color: var(--text-muted);
}

.unit-toggle {
  display: flex;
  gap: var(--spacing-xs);
  margin-bottom: var(--spacing-md);
}

.unit-toggle button {
  flex: 1;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 2px solid var(--light-bg-alt);
  background: white;
  border-radius: var(--radius-md);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.unit-toggle button.active {
  background: var(--primary-purple);
  border-color: var(--primary-purple);
  color: white;
}

/* Radio & Checkbox Groups */
.radio-group,
.checkbox-group {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.radio-item,
.checkbox-item {
  flex: 1;
  min-width: 100px;
}

.radio-item input,
.checkbox-item input {
  display: none;
}

.radio-item label,
.checkbox-item label {
  display: block;
  padding: var(--spacing-md);
  text-align: center;
  border: 2px solid var(--light-bg-alt);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
  margin-bottom: 0;
}

.radio-item input:checked + label,
.checkbox-item input:checked + label {
  background: var(--primary-purple);
  border-color: var(--primary-purple);
  color: white;
}

/* Results Section */
.results-section {
  background: var(--gradient-card);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  margin-top: var(--spacing-xl);
  border: 1px solid rgba(127, 86, 217, 0.2);
}

.results-section h3 {
  margin-bottom: var(--spacing-lg);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.result-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-md) 0;
  border-bottom: 1px solid rgba(127, 86, 217, 0.1);
}

.result-item:last-child {
  border-bottom: none;
}

.result-label {
  font-weight: 500;
  color: var(--text-muted);
}

.result-value {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--primary-purple);
}

.result-value.highlight {
  font-size: 2rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.result-status {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 600;
}

.result-status.normal {
  background: rgba(34, 197, 94, 0.1);
  color: var(--accent-green);
}

.result-status.warning {
  background: rgba(249, 115, 22, 0.1);
  color: var(--accent-orange);
}

.result-status.danger {
  background: rgba(239, 68, 68, 0.1);
  color: var(--accent-red);
}

/* Progress Bar */
.progress-bar {
  height: 12px;
  background: var(--light-bg-alt);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-top: var(--spacing-sm);
}

.progress-fill {
  height: 100%;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
  transition: width 0.5s var(--transition-expo);
}

/* History Widget */
.history-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.history-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-sm);
  background: var(--light-bg-alt);
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
}

.history-item .history-value {
  font-weight: 600;
  color: var(--primary-purple);
}

.history-empty {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.875rem;
  padding: var(--spacing-md);
}

.clear-history {
  width: 100%;
  margin-top: var(--spacing-md);
  padding: var(--spacing-sm);
  background: transparent;
  border: 1px solid var(--light-bg-alt);
  border-radius: var(--radius-md);
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.clear-history:hover {
  background: var(--accent-red);
  border-color: var(--accent-red);
  color: white;
}

/* Related Calculators */
.related-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.related-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm);
  border-radius: var(--radius-sm);
  transition: background var(--transition-fast);
}

.related-item:hover {
  background: var(--light-bg-alt);
}

.related-item i {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-card);
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
}

.related-item span {
  font-size: 0.875rem;
  font-weight: 500;
}

/* Ad Containers */
.ad-container {
  background: var(--light-bg-alt);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 0.75rem;
  text-align: center;
  overflow: hidden;
}

.ad-container.sidebar-ad {
  min-height: 250px;
}

.ad-container.inline-ad {
  min-height: 90px;
  margin: var(--spacing-xl) 0;
}

.ad-label {
  position: absolute;
  top: 4px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 0.625rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
}

/* Breadcrumb */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-lg);
  font-size: 0.875rem;
}

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

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

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

.breadcrumb-current {
  color: var(--text-dark);
  font-weight: 600;
}

/* Info Box */
.info-box {
  background: rgba(59, 130, 246, 0.1);
  border-left: 4px solid var(--accent-blue);
  padding: var(--spacing-md);
  border-radius: var(--radius-sm);
  margin: var(--spacing-md) 0;
}

.info-box h4 {
  color: var(--accent-blue);
  margin-bottom: var(--spacing-xs);
  font-size: 0.9rem;
}

.info-box p {
  font-size: 0.875rem;
  margin: 0;
}

/* Formula Display */
.formula-box {
  background: var(--dark-bg);
  color: var(--text-light);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  font-family: 'Courier New', monospace;
  font-size: 0.875rem;
  margin: var(--spacing-md) 0;
  overflow-x: auto;
}

/* Footer */
.footer {
  background: var(--dark-bg);
  color: var(--text-light);
  padding: var(--spacing-3xl) 0 var(--spacing-xl);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-2xl);
}

.footer-brand .logo {
  color: white;
  margin-bottom: var(--spacing-md);
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
}

.footer-links h4 {
  color: white;
  margin-bottom: var(--spacing-md);
  font-size: 1rem;
}

.footer-links ul {
  list-style: none;
}

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

.footer-links a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: var(--primary-purple-light);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--spacing-xl);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

.footer-bottom p {
  color: rgba(255, 255, 255, 0.5);
  font-size: 0.875rem;
}

.social-links {
  display: flex;
  gap: var(--spacing-md);
}

.social-links a {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
}

.social-links a:hover {
  background: var(--primary-purple);
  transform: translateY(-2px);
}

/* Animations */
@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.animate-pulse {
  animation: pulse 2s infinite;
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  bottom: var(--spacing-lg);
  right: var(--spacing-lg);
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.toast {
  background: var(--dark-bg);
  color: white;
  padding: var(--spacing-md) var(--spacing-lg);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-xl);
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  animation: slideIn 0.3s var(--transition-expo);
}

.toast.success {
  border-left: 4px solid var(--accent-green);
}

.toast.error {
  border-left: 4px solid var(--accent-red);
}

/* Responsive Design */
@media (max-width: 1024px) {
  .calculator-container {
    grid-template-columns: 1fr;
  }
  
  .calculator-sidebar {
    order: -1;
  }
  
  .sidebar-widget {
    display: none;
  }
  
  .sidebar-widget:first-child {
    display: block;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
  }
  
  .mobile-menu-btn {
    display: flex;
  }
  
  .hero {
    padding: 100px 0 60px;
  }
  
  .hero-stats {
    flex-direction: column;
    gap: var(--spacing-lg);
  }
  
  .hero-buttons {
    flex-direction: column;
    width: 100%;
    max-width: 300px;
    margin: 0 auto;
  }
  
  .btn {
    width: 100%;
  }
  
  .form-row {
    grid-template-columns: 1fr;
  }
  
  .radio-group,
  .checkbox-group {
    flex-direction: column;
  }
  
  .radio-item,
  .checkbox-item {
    min-width: auto;
  }
  
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
  
  .ad-container.sidebar-ad {
    min-height: 100px;
  }
}

@media (max-width: 480px) {
  :root {
    --spacing-lg: 1rem;
    --spacing-xl: 1.5rem;
    --spacing-2xl: 2rem;
  }
  
  .calculator-main {
    padding: var(--spacing-md);
  }
  
  .result-item {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--spacing-xs);
  }
}

/* Print Styles */
@media print {
  .navbar,
  .calculator-sidebar,
  .ad-container,
  .footer {
    display: none !important;
  }
  
  .calculator-page {
    padding-top: 0;
  }
  
  .calculator-main {
    box-shadow: none;
  }
}

/* Accessibility */
@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;
  }
}

/* Focus Visible */
:focus-visible {
  outline: 2px solid var(--primary-purple);
  outline-offset: 2px;
}

/* Selection */
::selection {
  background: var(--primary-purple);
  color: white;
}


/* Mobile Menu */
.mobile-menu {
    display: none;
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: #fff;
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-lg);
    z-index: 999;
    max-height: calc(100vh - 70px);
    overflow-y: auto;
    transition: all 0.3s ease;
}

.mobile-menu.active {
    display: block;
}

.mobile-menu ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.mobile-menu li {
    margin-bottom: var(--spacing-md);
}

.mobile-menu a {
    display: block;
    padding: var(--spacing-sm) 0;
    font-weight: 500;
    color: var(--text-dark);
    border-bottom: 1px solid var(--light-bg-alt);
}

.mobile-menu a:hover {
    color: var(--primary-purple);
}

/* Modal Search */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(5px);
    z-index: 10000;
    align-items: center;
    justify-content: center;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: white;
    border-radius: var(--radius-lg);
    width: 90%;
    max-width: 600px;
    max-height: 80vh;
    overflow: hidden;
    box-shadow: var(--shadow-xl);
    animation: modalFadeIn 0.3s var(--transition-expo);
}

@keyframes modalFadeIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    border-bottom: 2px solid var(--light-bg-alt);
}

.modal-header h3 {
    margin: 0;
    font-size: 1.25rem;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-muted);
    transition: color var(--transition-fast);
    line-height: 1;
    padding: var(--spacing-xs);
}

.modal-close:hover {
    color: var(--accent-red);
}

.modal-body {
    padding: var(--spacing-lg);
    max-height: calc(80vh - 80px);
    overflow-y: auto;
}

.search-input {
    width: 100%;
    padding: var(--spacing-md);
    border: 2px solid var(--light-bg-alt);
    border-radius: var(--radius-md);
    font-size: 1rem;
    margin-bottom: var(--spacing-lg);
    transition: border-color var(--transition-fast);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-purple);
    box-shadow: 0 0 0 3px rgba(127, 86, 217, 0.1);
}

.search-results {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.search-result-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    background: var(--light-bg-alt);
    transition: background var(--transition-fast);
    text-decoration: none;
    color: var(--text-dark);
}

.search-result-item:hover {
    background: var(--primary-purple-light);
    color: white;
}

.search-result-item i {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: white;
    border-radius: var(--radius-sm);
    color: var(--primary-purple);
    font-size: 1.1rem;
}

.search-result-item div {
    flex: 1;
}

.search-result-item strong {
    display: block;
    font-size: 1rem;
    margin-bottom: 2px;
}

.search-result-item span {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.search-result-item:hover span {
    color: rgba(255, 255, 255, 0.9);
}

.search-no-results {
    text-align: center;
    color: var(--text-muted);
    padding: var(--spacing-xl);
}

@media (min-width: 769px) {
  .mobile-menu {
    display: none !important;
  }
}