/* =============================================================================
   BMI Health Calculator - Main Styles
   ============================================================================= */

/* CSS Custom Properties (Variables) - Theme System */
:root {
  /* Brand Colors (consistent across themes) */
  --primary-color: #2c7a2c;
  --primary-light: #4a9a4a;
  --primary-dark: #1e5a1e;
  --secondary-color: #3498db;
  --accent-color: #e74c3c;
  
  /* Health Category Colors (consistent across themes) */
  --underweight-color: #3498db;
  --normal-color: #2ecc71;
  --overweight-color: #f39c12;
  --obese-color: #e74c3c;
  
  /* Static Colors */
  --white-static: #ffffff;
  --black-static: #000000;
  
  /* Shadow System */
  --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.15);
}

/* Light Theme */
:root {
  /* Background Colors */
  --bg-primary: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #e9ecef;
  
  /* Text Colors */
  --text-primary: #212529;
  --text-secondary: #6c757d;
  --text-light: #adb5bd;
  
  /* Border Colors */
  --border-color: #dee2e6;
  --border-light: #e9ecef;
  --border-dark: #adb5bd;
  
  /* Dynamic Colors (updated by theme) */
  --white: var(--white-static);
  --black: var(--black-static);
}

/* Dark Mode Theme */
.dark-mode {
  /* Background Colors - Dark */
  --bg-primary: #1a1a1a;
  --bg-secondary: #2d2d2d;
  --bg-tertiary: #3a3a3a;
  
  /* Text Colors - Dark */
  --text-primary: #f0f0f0;
  --text-secondary: #b0b0b0;
  --text-light: #888888;
  
  /* Border Colors - Dark */
  --border-color: #404040;
  --border-light: #4a4a4a;
  --border-dark: #606060;
  
  /* Dynamic Colors for Dark Mode */
  --white: var(--black-static);
  --black: var(--white-static);
  
  /* Dark Mode Shadows */
  --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.5);
}

/* Shared Typography and Layout Variables */
:root {
  /* Typography */
  --font-family-primary: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  --font-family-secondary: 'Georgia', serif;
  --font-size-base: 16px;
  --font-size-sm: 14px;
  --font-size-lg: 18px;
  --font-size-xl: 24px;
  --font-size-xxl: 32px;
  --line-height-base: 1.5;
  --line-height-tight: 1.2;
  
  /* Extreme ultra-compact spacing for single-screen fit */
  --spacing-xs: 0.125rem;  /* 2px */
  --spacing-sm: 0.25rem;   /* 4px */
  --spacing-md: 0.375rem;  /* 6px */
  --spacing-lg: 0.5rem;    /* 8px */
  --spacing-xl: 0.625rem;  /* 10px */
  --spacing-xxl: 0.75rem;  /* 12px */
  
  /* Layout */
  --container-max-width: 1200px;
  --border-radius: 8px;
  --border-radius-sm: 4px;
  --border-radius-lg: 12px;
  
  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
  
  /* Transitions */
  --transition-fast: 0.15s ease-in-out;
  --transition-normal: 0.3s ease-in-out;
  --transition-slow: 0.5s ease-in-out;
}

/* =============================================================================
   Reset and Base Styles
   ============================================================================= */

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

html {
  font-size: var(--font-size-base);
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-primary);
  line-height: var(--line-height-base);
  color: var(--text-primary);
  background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background var(--transition-fast), color var(--transition-fast);
}

/* =============================================================================
   Accessibility - WCAG 2.1 AA Compliant
   ============================================================================= */

/* Skip Link */
/* Enhanced Focus States for Accessibility */
*:focus {
  outline: 3px solid var(--primary-color);
  outline-offset: 2px;
  outline-style: solid;
}

button:focus,
input:focus,
select:focus,
textarea:focus {
  outline: 3px solid var(--primary-color);
  outline-offset: 2px;
  box-shadow: 0 0 0 2px var(--white), 0 0 0 5px var(--primary-color);
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --text-primary: #000000;
    --bg-primary: #ffffff;
    --border-color: #000000;
    --primary-color: #0000ff;
  }
}

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

/* Screen Reader Only */
.sr-only {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0, 0, 0, 0) !important;
  white-space: nowrap !important;
  border: 0 !important;
}

/* Screen Reader Announcements */
.sr-live {
  position: absolute;
  left: -10000px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

/* Touch Target Sizes - Minimum 44px */
button,
.btn,
input[type="button"],
input[type="submit"],
input[type="reset"],
.nav-link,
.alert-close {
  min-height: 44px;
  min-width: 44px;
  touch-action: manipulation;
}

/* Keyboard Navigation Indicators */
.keyboard-user *:focus {
  outline: 3px solid var(--primary-color) !important;
  outline-offset: 2px !important;
}

/* High contrast borders */
.high-contrast {
  border: 2px solid currentColor !important;
}

/* =============================================================================
   Typography
   ============================================================================= */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-family-primary);
  font-weight: 600;
  line-height: var(--line-height-tight);
  color: var(--text-primary);
  margin-bottom: var(--spacing-md);
}

h1 {
  font-size: var(--font-size-xxl);
  font-weight: 700;
}

h2 {
  font-size: var(--font-size-xl);
}

h3 {
  font-size: var(--font-size-lg);
}

h4, h5, h6 {
  font-size: var(--font-size-base);
}

p {
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

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

a:hover,
a:focus {
  color: var(--primary-dark);
  text-decoration: underline;
}

/* =============================================================================
   Layout
   ============================================================================= */

.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-xs);
}

.section {
  padding: 0;
  min-height: auto;
}

.section:not(.active) {
  display: none;
}

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

.section-header h2 {
  color: var(--primary-color);
  margin-bottom: var(--spacing-sm);
}

.section-description {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* =============================================================================
   Header
   ============================================================================= */

.header {
  background: var(--white);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-xs) 0;
  min-height: 50px;
}

.logo h1 {
  color: var(--primary-color);
  font-size: var(--font-size-lg);
  margin-bottom: 0;
}

.tagline {
  color: var(--primary-color);
  font-size: var(--font-size-sm);
  font-weight: 500;
  margin: 0;
  opacity: 0.9;
}

.main-nav ul {
  display: flex;
  list-style: none;
  list-style-type: none;
  gap: var(--spacing-lg);
  align-items: center;
  margin: 0;
  padding: 0;
}

.main-nav li {
  list-style: none;
  list-style-type: none;
  margin: 0;
  padding: 0;
}

.main-nav li::before,
.main-nav li::after {
  display: none !important;
  content: none !important;
}

.nav-link {
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--border-radius);
  font-weight: 600;
  transition: all var(--transition-fast);
  color: var(--text-primary);
  border: 2px solid transparent;
  position: relative;
  text-decoration: none;
}

.nav-link::before,
.nav-link::after {
  display: none !important;
  content: none !important;
}

.nav-link.active::before,
.nav-link.active::after {
  display: none !important;
  content: none !important;
}

.nav-link:hover,
.nav-link:focus {
  background-color: var(--bg-tertiary);
  text-decoration: none;
  border-color: var(--primary-light);
  transform: translateY(-1px);
}

.nav-link.active {
  background-color: var(--primary-color);
  color: var(--white);
  border-color: var(--primary-dark);
  box-shadow: 0 2px 8px rgba(44, 122, 44, 0.3);
}

/* Removed circular dot indicator - active state shown by background color only */

/* Theme Toggle Button */
.theme-toggle {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: var(--spacing-xs) var(--spacing-sm);
  cursor: pointer;
  font-size: 18px;
  transition: all var(--transition-fast);
  margin-right: var(--spacing-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
}

.theme-toggle:hover {
  background: var(--bg-secondary);
  transform: scale(1.05);
}

.theme-toggle:active {
  transform: scale(0.98);
}

.theme-icon {
  line-height: 1;
  transition: transform var(--transition-fast);
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-sm);
}

.hamburger {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  position: relative;
}

.hamburger::before,
.hamburger::after {
  content: '';
  position: absolute;
  width: 100%;
  height: 2px;
  background: var(--text-primary);
  transition: all var(--transition-fast);
}

.hamburger::before {
  top: -8px;
}

.hamburger::after {
  bottom: -8px;
}

/* =============================================================================
   Forms
   ============================================================================= */

.form-group {
  margin-bottom: var(--spacing-sm);
  padding: var(--spacing-sm);
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
  border: 1px solid var(--border-light);
}

.form-group legend {
  font-weight: 600;
  font-size: var(--font-size-lg);
  color: var(--text-primary);
  margin-bottom: var(--spacing-md);
  padding: 0;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
}

.input-group {
  margin-bottom: var(--spacing-md);
}

.input-group label {
  display: block;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
  font-size: var(--font-size-sm);
}

.input-group input,
.input-group select {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 2px solid var(--border-color);
  border-radius: var(--border-radius);
  font-size: var(--font-size-base);
  transition: all var(--transition-fast);
  background-color: var(--white);
}

.input-group input:focus,
.input-group select:focus {
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(44, 122, 44, 0.1);
}

.input-group input:invalid {
  border-color: var(--accent-color);
}

.input-help {
  display: block;
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-top: var(--spacing-xs);
}

/* Unit Toggle */
.unit-toggle {
  display: flex;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.toggle-label {
  display: flex;
  align-items: center;
  cursor: pointer;
  font-weight: 500;
}

.toggle-label input[type="radio"] {
  width: auto;
  margin-right: var(--spacing-xs);
}

/* Measurement Inputs */
.measurement-group {
    margin-bottom: var(--spacing-xs);
}

.measurement-label {
    display: block;
    font-weight: 600;
    font-size: var(--font-size-base);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

.measurement-inputs {
    position: relative;
}

.measurement-inputs .input-group {
    position: relative;
    margin-bottom: var(--spacing-xs);
}

/* Generic unit label - overridden by inline-units-row specific styles */
.unit-label {
    color: var(--text-secondary);
    font-weight: 500;
    pointer-events: none;
}

/* Height Converter Styles */
.height-converter,
.weight-converter {
    background: linear-gradient(145deg, var(--white), var(--bg-secondary));
    border-radius: var(--border-radius);
    padding: var(--spacing-xs);
    border: 1px solid var(--border-light);
    transition: all var(--transition-fast);
    margin-bottom: var(--spacing-xs);
    box-shadow: 0 1px 4px rgba(0,0,0,0.08);
    position: relative;
    overflow: hidden;
}

.height-converter::before,
.weight-converter::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--primary-light));
    opacity: 0.8;
}

.height-converter:focus-within,
.weight-converter:focus-within {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(44, 122, 44, 0.1), 0 4px 8px rgba(0,0,0,0.1);
}

.inline-units-row .input-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(44, 122, 44, 0.2);
    background-color: rgba(44, 122, 44, 0.05);
}

.inline-units-row .input-group input:focus + .unit-label {
    color: var(--primary-color);
    font-weight: 700;
}

.inline-units-row .input-group:hover input {
    border-color: var(--primary-light);
}

.inline-units-row .input-group:hover .unit-label {
    color: var(--primary-color);
}

.height-converter.converting,
.weight-converter.converting {
    border-color: var(--success-color);
    background: var(--bg-tertiary);
    transform: scale(1.01);
}

/* ENTERPRISE-GRADE INPUT SYSTEM */
.inline-units-row {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: 0;
    padding: var(--spacing-xs);
    background: var(--white);
    border-radius: var(--border-radius);
    border: 1px solid var(--border-light);
    min-height: 45px;
    box-shadow: 0 1px 4px rgba(0,0,0,0.08);
    transition: all var(--transition-fast);
}

.inline-units-row:focus-within {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(44, 122, 44, 0.1);
}

/* Each input group takes exactly one grid cell */
.inline-units-row .input-group {
    display: flex;
    flex-direction: row;
    align-items: center;
    position: relative;
    margin: 0;
    padding: 0 4px;
    min-width: 85px;
    gap: 6px;
}

/* Enterprise-grade input fields - optimized for side-by-side labels */
.inline-units-row .input-group input {
    display: block;
    width: 60px;
    height: 32px;
    padding: 4px 8px;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    font-size: var(--font-size-sm);
    font-weight: 600;
    text-align: center;
    background: #E5E5E5;
    color: #212529;
    box-sizing: border-box;
    margin: 0;
    transition: all var(--transition-fast);
    -webkit-appearance: none;
    -moz-appearance: textfield;
    appearance: textfield;
}

.inline-units-row .input-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    background: #F0F0F0;
    color: #212529;
    box-shadow: 0 0 0 3px rgba(44, 122, 44, 0.2), 0 2px 8px rgba(44, 122, 44, 0.1);
    transform: scale(1.05);
}

.inline-units-row .input-group input:hover {
    border-color: var(--primary-light);
    background: #F0F0F0;
    color: #212529;
}

/* Unit labels positioned to the right of inputs to prevent overlap */
.inline-units-row .unit-label {
    display: block;
    position: static;
    font-size: 11px;
    font-weight: 700;
    color: var(--text-secondary);
    text-align: left;
    margin: 0;
    padding: 0;
    line-height: 1;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    min-width: 20px;
    flex-shrink: 0;
}

.inline-units-row .input-group:focus-within .unit-label {
    color: var(--primary-color);
}

/* Clear separator design */
.unit-separator {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 32px;
    padding: 0 var(--spacing-xs);
    background: var(--primary-color);
    color: var(--white);
    border-radius: var(--border-radius-sm);
    font-size: var(--font-size-sm);
    font-weight: 700;
    margin: 0;
    box-shadow: 0 1px 2px rgba(44, 122, 44, 0.2);
}

/* COMPREHENSIVE SPINNER REMOVAL - All Browsers */
/* Webkit browsers (Chrome, Safari, Edge) */
input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
    -webkit-appearance: none !important;
    -moz-appearance: none !important;
    appearance: none !important;
    margin: 0 !important;
    display: none !important;
    width: 0 !important;
    height: 0 !important;
    opacity: 0 !important;
    visibility: hidden !important;
}

/* Firefox */
input[type="number"] {
    -moz-appearance: textfield !important;
    appearance: textfield !important;
}

/* Ensure no spinners on all number inputs */
input[type="number"],
.inline-units-row input[type="number"],
#height-cm,
#height-feet,
#height-inches,
#weight-kg,
#weight-lbs {
    -webkit-appearance: none !important;
    -moz-appearance: textfield !important;
    appearance: textfield !important;
}

/* Additional comprehensive removal */
input[type="number"]::-webkit-inner-spin-button,
input[type="number"]::-webkit-outer-spin-button,
.inline-units-row input[type="number"]::-webkit-inner-spin-button,
.inline-units-row input[type="number"]::-webkit-outer-spin-button,
#height-cm::-webkit-inner-spin-button,
#height-cm::-webkit-outer-spin-button,
#height-feet::-webkit-inner-spin-button,
#height-feet::-webkit-outer-spin-button,
#height-inches::-webkit-inner-spin-button,
#height-inches::-webkit-outer-spin-button,
#weight-kg::-webkit-inner-spin-button,
#weight-kg::-webkit-outer-spin-button,
#weight-lbs::-webkit-inner-spin-button,
#weight-lbs::-webkit-outer-spin-button {
    -webkit-appearance: none !important;
    appearance: none !important;
    display: none !important;
    margin: 0 !important;
    width: 0 !important;
    height: 0 !important;
    opacity: 0 !important;
    visibility: hidden !important;
    position: absolute !important;
    right: -1000px !important;
}

/* Converting animation */
.height-converter.converting,
.weight-converter.converting {
    border-color: var(--primary-color) !important;
    background: linear-gradient(135deg, rgba(44, 122, 44, 0.05), rgba(44, 122, 44, 0.02)) !important;
    transform: scale(1.02);
    box-shadow: 0 4px 20px rgba(44, 122, 44, 0.15) !important;
}

.height-converter.converting .inline-units-row,
.weight-converter.converting .inline-units-row {
    background: rgba(44, 122, 44, 0.03);
    border-color: var(--primary-light);
}

/* Responsive adjustments for smaller screens */
@media (max-width: 768px) {
    .inline-units-row {
        gap: var(--spacing-xs);
        padding: var(--spacing-md);
        flex-wrap: wrap;
        justify-content: center;
        min-height: 60px;
    }
    
    .inline-units-row .input-group {
        gap: 6px;
        min-width: 85px;
    }
    
    .inline-units-row .input-group input {
        width: 65px;
        font-size: var(--font-size-base);
        padding: 6px 8px;
        height: 40px;
    }
    
    .unit-separator {
        padding: 8px 12px;
        font-size: var(--font-size-base);
        margin: 0 var(--spacing-xs);
        height: 40px;
    }
    
    .inline-units-row .unit-label {
        font-size: 10px;
        min-height: 12px;
        margin-top: 4px;
    }
    
    .height-converter,
    .weight-converter {
        padding: var(--spacing-md);
    }
}

@media (max-width: 480px) {
    .theme-toggle {
        width: 36px;
        height: 36px;
        font-size: 16px;
        margin-right: var(--spacing-xs);
    }

    .inline-units-row {
        flex-direction: column;
        align-items: center;
        gap: var(--spacing-md);
        min-height: auto;
        padding: var(--spacing-sm);
    }
    
    .inline-units-row .input-group {
        margin-bottom: var(--spacing-xs);
        min-width: 90px;
        gap: 4px;
    }
    
    .inline-units-row .input-group input {
        width: 65px;
    }
    
    .inline-units-row .unit-label {
        font-size: 10px;
        min-width: 18px;
    }
    
    .inline-units-row .unit-label {
        font-size: 10px;
        margin-top: 4px;
    }
    
    .unit-separator {
        order: 2;
        margin: var(--spacing-xs) 0;
        font-size: 12px;
    }
    
    .inline-units-row .input-group:first-child {
        order: 1;
    }
    
    .inline-units-row .input-group:nth-child(3) {
        order: 3;
    }
    
    .inline-units-row .input-group:last-child {
        order: 4;
    }
}





.conversion-info {
    text-align: center;
    margin-top: var(--spacing-sm);
}

.conversion-text {
    text-align: center;
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-top: var(--spacing-sm);
    font-style: italic;
    transition: color var(--transition-fast);
}

.conversion-text {
    color: var(--text-secondary);
    font-style: normal;
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    background: rgba(44, 122, 44, 0.05);
    border-radius: var(--border-radius);
    border: 1px solid rgba(44, 122, 44, 0.1);
    transition: all var(--transition-fast);
}

.height-metric .input-group input,
.height-imperial .input-group input {
    background: var(--white);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: var(--font-size-base);
    transition: all var(--transition-fast);
}

.height-metric .input-group input:focus,
.height-imperial .input-group input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(44, 122, 44, 0.1);
    outline: none;
}

.height-metric .input-help,
.height-imperial .input-help {
    display: block;
    text-align: center;
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-top: var(--spacing-xs);
    font-weight: 500;
}/* Form Actions */
.form-actions {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-sm);
}

/* =============================================================================
   Buttons
   ============================================================================= */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-xs) var(--spacing-md);
  border: 1px solid transparent;
  border-radius: var(--border-radius-sm);
  font-size: var(--font-size-sm);
  font-weight: 500;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  min-height: 32px;
  gap: var(--spacing-xs);
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
  color: var(--white);
  border-color: var(--primary-color);
  box-shadow: 0 2px 8px rgba(44, 122, 44, 0.2);
  font-weight: 600;
}

.btn-primary:hover:not(:disabled),
.btn-primary:focus:not(:disabled) {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
  border-color: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(44, 122, 44, 0.3);
}

.btn-secondary {
  background-color: transparent;
  color: var(--primary-color);
  border-color: var(--primary-color);
  font-weight: 600;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.btn-secondary:hover:not(:disabled),
.btn-secondary:focus:not(:disabled) {
  background-color: var(--primary-color);
  color: var(--white);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(44, 122, 44, 0.2);
}

.calculate-btn {
  flex: 1;
  font-size: var(--font-size-base);
  padding: var(--spacing-xs) var(--spacing-md);
}

/* =============================================================================
   Cards
   ============================================================================= */

.card {
  background: var(--white);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-md);
  overflow: hidden;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.card-header {
  padding: var(--spacing-lg);
  border-bottom: 1px solid var(--border-light);
}

.card-body {
  padding: var(--spacing-lg);
}

.card-footer {
  padding: var(--spacing-lg);
  border-top: 1px solid var(--border-light);
  background-color: var(--bg-secondary);
}

/* =============================================================================
   Calculator Specific Styles
   ============================================================================= */

.calculator-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-sm);
  align-items: start;
}

.calculator-input-card,
.calculator-results-card {
  background: var(--white);
  border-radius: var(--border-radius);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  border: 1px solid rgba(44, 122, 44, 0.1);
  padding: var(--spacing-md);
  transition: all var(--transition-fast);
}

.calculator-input-card:hover,
.calculator-results-card:hover {
  box-shadow: 0 12px 48px rgba(0, 0, 0, 0.15);
  border-color: rgba(44, 122, 44, 0.2);
  transform: translateY(-2px);
}

/* BMI Results */
.bmi-results {
  text-align: center;
}

.results-header {
  margin-bottom: var(--spacing-xl);
}

.results-header h3 {
  color: var(--primary-color);
  margin-bottom: var(--spacing-md);
}

.bmi-value-display {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.bmi-number {
  font-size: 4rem;
  font-weight: 700;
  color: var(--primary-color);
  line-height: 1;
}

.bmi-category {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--text-secondary);
}

/* BMI Gauge */
.bmi-gauge {
  margin: var(--spacing-xl) 0;
}

.gauge-container {
  max-width: 400px;
  margin: 0 auto;
}

.gauge-bar {
  height: 20px;
  border-radius: 10px;
  overflow: hidden;
  position: relative;
  margin-bottom: var(--spacing-sm);
}

.gauge-sections {
  display: flex;
  height: 100%;
}

.gauge-section {
  flex: 1;
  position: relative;
}

.gauge-section.underweight {
  background-color: var(--underweight-color);
}

.gauge-section.normal {
  background-color: var(--normal-color);
}

.gauge-section.overweight {
  background-color: var(--overweight-color);
}

.gauge-section.obese {
  background-color: var(--obese-color);
}

.gauge-pointer {
  position: absolute;
  top: -5px;
  width: 4px;
  height: 30px;
  background: var(--text-primary);
  border-radius: 2px;
  transform: translateX(-50%);
  transition: left var(--transition-normal);
}

.gauge-labels {
  display: flex;
  justify-content: space-between;
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-top: var(--spacing-xs);
}

/* Health Insights */
.health-insights {
  display: grid;
  gap: var(--spacing-lg);
  margin-top: var(--spacing-xl);
  text-align: left;
}

.insight-card {
  padding: var(--spacing-lg);
  border-radius: var(--border-radius);
  border: 1px solid var(--border-light);
}

.insight-card h4 {
  color: var(--primary-color);
  margin-bottom: var(--spacing-sm);
  font-size: var(--font-size-base);
}

.risk-indicator {
  margin-bottom: var(--spacing-sm);
}

.risk-badge {
  display: inline-block;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--border-radius-sm);
  font-size: var(--font-size-sm);
  font-weight: 600;
  background-color: var(--normal-color);
  color: var(--white);
}

.weight-range {
  display: flex;
  align-items: baseline;
  gap: var(--spacing-sm);
}

.range-values {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--primary-color);
}

.range-label {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
}

.recommendations-list {
  list-style: none;
  padding: 0;
}

.recommendations-list li {
  padding: var(--spacing-xs) 0;
  position: relative;
  padding-left: var(--spacing-lg);
}

.recommendations-list li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--normal-color);
  font-weight: 700;
}

/* Results Placeholder */
.results-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 400px;
  text-align: center;
  color: var(--text-secondary);
}

.placeholder-content {
  max-width: 300px;
}

.placeholder-icon {
  font-size: 4rem;
  margin-bottom: var(--spacing-md);
}

.placeholder-content h3 {
  color: var(--text-primary);
  margin-bottom: var(--spacing-sm);
}

/* =============================================================================
   Footer
   ============================================================================= */

.footer {
  background: var(--dark-gray);
  color: var(--white);
  padding: var(--spacing-xxl) 0 var(--spacing-lg);
  margin-top: auto;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

.footer-section h4 {
  color: var(--text-secondary);
  margin-bottom: var(--spacing-md);
}

.footer-section p {
  color: var(--text-light);
  margin-bottom: var(--spacing-sm);
}

.footer-section ul {
  list-style: none;
  padding: 0;
}

.footer-section ul li {
  margin-bottom: var(--spacing-xs);
}

.footer-section ul li a {
  color: var(--text-light);
  transition: color var(--transition-fast);
}

.footer-section ul li a:hover,
.footer-section ul li a:focus {
  color: var(--white);
}

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--medium-gray);
  color: var(--text-light);
  font-size: var(--font-size-sm);
}



/* =============================================================================
   Validation Styles
   ============================================================================= */

.validation-error {
    color: var(--accent-color);
    font-size: var(--font-size-sm);
    margin-top: var(--spacing-xs);
    display: block;
    text-align: left;
    width: 100%;
}

.inline-units-row .input-group input.invalid {
    border-color: var(--accent-color);
    background-color: rgba(231, 76, 60, 0.05);
}

.inline-units-row .input-group input.invalid + .unit-label {
    color: var(--accent-color);
}

/* =============================================================================
   Utility Classes
   ============================================================================= */

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

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

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

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

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

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

.bg-primary {
  background-color: var(--primary-color);
}

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

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--spacing-xs); }
.mt-2 { margin-top: var(--spacing-sm); }
.mt-3 { margin-top: var(--spacing-md); }
.mt-4 { margin-top: var(--spacing-lg); }
.mt-5 { margin-top: var(--spacing-xl); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--spacing-xs); }
.mb-2 { margin-bottom: var(--spacing-sm); }
.mb-3 { margin-bottom: var(--spacing-md); }
.mb-4 { margin-bottom: var(--spacing-lg); }
.mb-5 { margin-bottom: var(--spacing-xl); }

.p-0 { padding: 0; }
.p-1 { padding: var(--spacing-xs); }
.p-2 { padding: var(--spacing-sm); }
.p-3 { padding: var(--spacing-md); }
.p-4 { padding: var(--spacing-lg); }
.p-5 { padding: var(--spacing-xl); }

.d-none {
  display: none !important;
}

.d-block {
  display: block !important;
}

.d-flex {
  display: flex !important;
}

.d-grid {
  display: grid !important;
}

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

/* =============================================================================
   Animation and Loading States
   ============================================================================= */

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

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

@keyframes slideIn {
  from { transform: translateX(-100%); }
  to { transform: translateX(0); }
}

.loading {
  position: relative;
}

.loading::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 20px;
  height: 20px;
  margin: -10px 0 0 -10px;
  border: 2px solid var(--border-light);
  border-top-color: var(--primary-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

.fade-in {
  animation: fadeIn 0.5s ease-out forwards;
}

.slide-in {
  animation: slideIn 0.3s ease-out forwards;
}

/* =============================================================================
   Error States
   ============================================================================= */

.error {
  border-color: var(--accent-color) !important;
  background-color: rgba(231, 76, 60, 0.05);
}

.error-message {
  color: var(--accent-color);
  font-size: var(--font-size-sm);
  margin-top: var(--spacing-xs);
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.error-message::before {
  content: '⚠';
  font-weight: bold;
}

.success-message {
  color: var(--normal-color);
  font-size: var(--font-size-sm);
  margin-top: var(--spacing-xs);
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.success-message::before {
  content: '✓';
  font-weight: bold;
}

/* =============================================================================
   Education Content Styles
   ============================================================================= */

.education-article {
  max-width: 800px;
  margin: 0 auto;
  line-height: 1.6;
}

.article-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
  padding-bottom: var(--spacing-lg);
  border-bottom: 2px solid var(--primary-color);
}

.article-header h2 {
  color: var(--primary-color);
  margin-bottom: var(--spacing-sm);
}

.article-subtitle {
  color: var(--text-secondary);
  font-size: var(--font-size-lg);
  margin: 0;
}

.content-section {
  margin-bottom: var(--spacing-xl);
}

.content-section h3 {
  color: var(--primary-color);
  border-bottom: 1px solid var(--border-light);
  padding-bottom: var(--spacing-xs);
  margin-bottom: var(--spacing-lg);
}

.formula-box {
  background: var(--bg-secondary);
  border: 2px solid var(--primary-light);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
  text-align: center;
}

.formula-box h4 {
  margin-top: 0;
  color: var(--primary-color);
}

.formula-box code {
  font-size: var(--font-size-xl);
  font-weight: bold;
  color: var(--primary-color);
  background: var(--white);
  padding: var(--spacing-sm);
  border-radius: var(--border-radius-sm);
  display: block;
  margin: var(--spacing-sm) 0;
}

.bmi-categories {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
  margin: var(--spacing-lg) 0;
}

.category-item {
  padding: var(--spacing-lg);
  border-radius: var(--border-radius);
  text-align: center;
  color: white;
  font-weight: bold;
}

.category-item.underweight { background: var(--underweight-color); }
.category-item.normal { background: var(--normal-color); }
.category-item.overweight { background: var(--overweight-color); }
.category-item.obese { background: var(--obese-color); }

.category-range {
  display: block;
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-xs);
}

.info-list, .risk-list, .goal-guidelines, .mistake-list, .planning-tips, .beginner-tips, .healthy-habits, .warning-signs {
  padding-left: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
}

.info-list li, .risk-list li, .goal-guidelines li, .mistake-list li, .planning-tips li, .beginner-tips li, .healthy-habits li, .warning-signs li {
  margin-bottom: var(--spacing-sm);
  padding-left: var(--spacing-xs);
  line-height: 1.6;
}

.education-article ul {
  margin: var(--spacing-md) 0;
}

.education-article ul ul {
  margin-top: var(--spacing-sm);
  margin-bottom: var(--spacing-sm);
}

.risk-box {
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
}

.risk-box.low-risk {
  background: rgba(52, 152, 219, 0.1);
  border-left: 4px solid var(--underweight-color);
}

.risk-box.medium-risk {
  background: rgba(243, 156, 18, 0.1);
  border-left: 4px solid var(--overweight-color);
}

.risk-box.high-risk {
  background: rgba(231, 76, 60, 0.1);
  border-left: 4px solid var(--obese-color);
}

.principle-cards, .macro-breakdown {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
}

.principle-card, .macro-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  transition: transform var(--transition-fast);
}

.principle-card:hover, .macro-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.principle-card h4, .macro-card h4 {
  color: var(--primary-color);
  margin-top: 0;
  margin-bottom: var(--spacing-sm);
}

.portion-guide {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-md);
  margin: var(--spacing-lg) 0;
}

.portion-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md);
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
}

.portion-visual {
  font-size: var(--font-size-xl);
}

.exercise-guidelines {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
}

.exercise-type {
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  border-left: 4px solid var(--primary-color);
}

.exercise-type h4 {
  color: var(--primary-color);
  margin-top: 0;
}

.safety-tips, .warning-box {
  background: rgba(243, 156, 18, 0.1);
  border: 1px solid var(--overweight-color);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
}

.safety-tips h4 {
  color: var(--overweight-color);
  margin-top: 0;
}

.barrier-solutions {
  margin: var(--spacing-lg) 0;
}

.barrier {
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
  border-left: 4px solid var(--secondary-color);
}

.barrier h4 {
  color: var(--secondary-color);
  margin-top: 0;
  margin-bottom: var(--spacing-sm);
}

.connection-factors, .stress-techniques {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
}

.factor, .technique {
  background: var(--bg-secondary);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  text-align: center;
}

.factor h4, .technique h4 {
  color: var(--primary-color);
  margin-top: 0;
}

.help-indicators {
  background: rgba(231, 76, 60, 0.1);
  border: 1px solid var(--accent-color);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
}

/* =============================================================================
   Footer Content Overlay Styles
   ============================================================================= */

.footer-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  padding: var(--spacing-lg);
}

.footer-overlay-content {
  background: var(--white);
  border-radius: var(--border-radius-lg);
  max-width: 700px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-lg);
}

.footer-overlay-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-lg);
  border-bottom: 1px solid var(--border-light);
  background: var(--bg-secondary);
  border-radius: var(--border-radius-lg) var(--border-radius-lg) 0 0;
}

.footer-overlay-header h3 {
  margin: 0;
  color: var(--primary-color);
}

.footer-overlay-close {
  background: none;
  border: none;
  font-size: var(--font-size-xl);
  cursor: pointer;
  padding: var(--spacing-xs);
  border-radius: var(--border-radius-sm);
  transition: background-color var(--transition-fast);
  color: var(--text-secondary);
}

.footer-overlay-close:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.footer-overlay-body {
  padding: var(--spacing-lg);
  line-height: 1.6;
}

.footer-overlay-body h4 {
  color: var(--primary-color);
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-sm);
}

.footer-overlay-body h4:first-child {
  margin-top: 0;
}

.footer-overlay-body ul {
  padding-left: var(--spacing-lg);
}

.footer-overlay-body li {
  margin-bottom: var(--spacing-xs);
}

.footer-overlay-body .highlight-box {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
}

.footer-overlay-body .contact-info {
  background: rgba(44, 122, 44, 0.1);
  border-left: 4px solid var(--primary-color);
  padding: var(--spacing-lg);
  margin: var(--spacing-lg) 0;
  border-radius: var(--border-radius-sm);
}

@media (max-width: 768px) {
  .footer-overlay {
    padding: var(--spacing-md);
  }
  
  .footer-overlay-content {
    max-height: 95vh;
  }
  
  .footer-overlay-header {
    padding: var(--spacing-md);
  }
  
  .footer-overlay-body {
    padding: var(--spacing-md);
  }
}

/* Welcome message styling */
.toast .alert-message h4 {
  color: var(--primary-color);
  font-size: var(--font-size-lg);
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
}

.toast .alert-message ul {
  margin: var(--spacing-sm) 0;
  padding-left: var(--spacing-lg);
}

.toast .alert-message li {
  margin-bottom: var(--spacing-xs);
  color: var(--text-primary);
}

/* =============================================================================
   Print Styles
   ============================================================================= */

@media print {
  * {
    background: transparent !important;
    color: black !important;
    box-shadow: none !important;
    text-shadow: none !important;
  }
  
  .header,
  .footer,
  .mobile-menu-toggle,
  .btn,
  .modal {
    display: none !important;
  }
  
  .main-content {
    margin: 0;
    padding: 0;
  }
  
  .section {
    display: block !important;
    page-break-inside: avoid;
  }
  
  h1, h2, h3 {
    page-break-after: avoid;
  }
}