/* CSS Variables for Theme Management */
:root {
    --primary-color: #1A1A2E;
    --secondary-color: #16213E;
    --tertiary-color: #0F3460;
    --accent-color: #E94560;
    --white-color: #FFFFFF;
    --light-gray: #f8f9fa;
    --dark-gray: #6c757d;
    --success-color: #28a745;
    --warning-color: #ffc107;
    --danger-color: #dc3545;
    --info-color: #17a2b8;
}

/* Dark Mode Variables */
[data-theme="dark"] {
    --bg-color: #1A1A2E;
    --text-color: #FFFFFF;
    --card-bg: #16213E;
    --border-color: #0F3460;
}

[data-theme="light"] {
    --bg-color: #FFFFFF;
    --text-color: #1A1A2E;
    --card-bg: #FFFFFF;
    --border-color: #dee2e6;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-color, #1A1A2E);
    background-color: var(--bg-color, #FFFFFF);
    transition: all 0.3s ease;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    margin-bottom: 1rem;
}

.display-4 {
    font-weight: 700;
}

/* Custom Bootstrap Overrides */
.bg-primary {
    background-color: var(--primary-color) !important;
}

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

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

.text-accent {
    color: var(--accent-color) !important;
}

.btn-accent {
    background-color: var(--accent-color);
    border-color: var(--accent-color);
    color: white;
}

.btn-accent:hover {
    background-color: #d73652;
    border-color: #d73652;
    color: white;
}

/* Navigation */
.navbar {
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    backdrop-filter: blur(10px);
}

.navbar-brand {
    font-weight: 700;
    font-size: 1.5rem;
}

/* Hero Section */
.hero-section {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 50%, var(--tertiary-color) 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000"><polygon fill="%23ffffff05" points="0,1000 1000,0 1000,1000"/></svg>');
    background-size: cover;
}

.hero-image {
    text-align: center;
    position: relative;
    z-index: 1;
}

/* Cards */
.card {
    border: none;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    background-color: var(--card-bg, #FFFFFF);
    border: 1px solid var(--border-color, #dee2e6);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.15);
}

.card-header {
    border-radius: 15px 15px 0 0 !important;
    border-bottom: none;
    padding: 1.5rem;
}

.card-body {
    padding: 2rem;
}

/* Step Form Styles */
.step-section {
    animation: fadeIn 0.5s ease-in-out;
}

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

.step-title {
    color: var(--primary-color);
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--accent-color);
    display: flex;
    align-items: center;
    gap: 1rem;
}

.step-title i {
    font-size: 2rem;
}

/* Form Controls */
.form-control, .form-select {
    border-radius: 10px;
    border: 2px solid #e9ecef;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    transition: all 0.3s ease;
    background-color: var(--card-bg, #FFFFFF);
    color: var(--text-color, #1A1A2E);
}

.form-control:focus, .form-select:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 0.2rem rgba(233, 69, 96, 0.25);
}

.form-label {
    font-weight: 600;
    color: var(--text-color, #1A1A2E);
    margin-bottom: 0.5rem;
}

/* Progress Bar */
.progress {
    height: 8px;
    border-radius: 10px;
    background-color: #e9ecef;
}

.progress-bar {
    border-radius: 10px;
    transition: width 0.6s ease;
}

/* Results Section */
.result-card {
    padding: 2rem;
    text-align: center;
    border-radius: 15px;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    margin-bottom: 1rem;
    transition: transform 0.3s ease;
}

.result-card:hover {
    transform: scale(1.05);
}

/* Category Breakdown */
.category-item {
    background: var(--card-bg, #FFFFFF);
    border: 1px solid var(--border-color, #dee2e6);
    border-radius: 10px;
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: all 0.3s ease;
}

.category-item:hover {
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transform: translateY(-2px);
}

.category-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.category-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent-color);
}

.category-percentage {
    font-size: 0.9rem;
    color: var(--dark-gray);
}

/* Chart Container */
#footprintChart {
    max-width: 100%;
    height: auto;
    border-radius: 10px;
    background: var(--card-bg, #FFFFFF);
}

/* FAQ Section */
.accordion-item {
    border: none;
    margin-bottom: 1rem;
    border-radius: 10px !important;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.accordion-button {
    background-color: var(--card-bg, #FFFFFF);
    color: var(--text-color, #1A1A2E);
    border: none;
    font-weight: 600;
    padding: 1.5rem;
}

.accordion-button:not(.collapsed) {
    background-color: var(--primary-color);
    color: white;
    box-shadow: none;
}

.accordion-body {
    background-color: var(--card-bg, #FFFFFF);
    color: var(--text-color, #1A1A2E);
    padding: 1.5rem;
}

/* Offcanvas */
.offcanvas {
    background-color: var(--card-bg, #FFFFFF);
    color: var(--text-color, #1A1A2E);
}

.offcanvas-header {
    border-bottom: 1px solid var(--border-color, #dee2e6);
    background-color: var(--primary-color);
    color: white;
}

.offcanvas-body {
    padding: 2rem;
}

.comparison-data {
    background: var(--light-gray);
    padding: 1rem;
    border-radius: 10px;
    margin-bottom: 1rem;
}

/* Tips Styles */
.tip-item {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    padding: 1rem;
    border-radius: 10px;
    margin-bottom: 1rem;
    border-left: 4px solid var(--accent-color);
}

.tip-category {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.tip-text {
    color: var(--dark-gray);
    margin-bottom: 0.5rem;
}

.tip-impact {
    font-size: 0.9rem;
    color: var(--success-color);
    font-weight: 600;
}

/* Ad Styles */
.admob-banner {
    margin: 2rem 0;
}

.adsbygoogle {
    border-radius: 10px;
    overflow: hidden;
}

/* Dark Mode Styles */
[data-theme="dark"] {
    background-color: var(--bg-color);
    color: var(--text-color);
}

[data-theme="dark"] .bg-light {
    background-color: var(--secondary-color) !important;
}

[data-theme="dark"] .text-dark {
    color: var(--text-color) !important;
}

[data-theme="dark"] .text-muted {
    color: #adb5bd !important;
}

[data-theme="dark"] .result-card {
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--tertiary-color) 100%);
    color: white;
}

[data-theme="dark"] .comparison-data {
    background: var(--secondary-color);
    color: white;
}

[data-theme="dark"] .tip-item {
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--tertiary-color) 100%);
    color: white;
}

[data-theme="dark"] .tip-text {
    color: #adb5bd;
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero-section {
        text-align: center;
        padding: 100px 0 50px;
    }
    
    .hero-image i {
        font-size: 8rem !important;
    }
    
    .display-4 {
        font-size: 2.5rem;
    }
    
    .card-body {
        padding: 1.5rem;
    }
    
    .step-title {
        font-size: 1.5rem;
    }
    
    .step-title i {
        font-size: 1.5rem;
    }
    
    .result-card {
        padding: 1.5rem;
        margin-bottom: 1rem;
    }
    
    .category-item {
        padding: 1rem;
    }
}

@media (max-width: 576px) {
    .container {
        padding: 0 15px;
    }
    
    .hero-section {
        padding: 80px 0 30px;
    }
    
    .display-4 {
        font-size: 2rem;
    }
    
    .card-body {
        padding: 1rem;
    }
    
    .btn-lg {
        padding: 0.75rem 1.5rem;
        font-size: 1rem;
    }
    
    .offcanvas-body {
        padding: 1rem;
    }
}

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid #f3f3f3;
    border-top: 3px solid var(--accent-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* Utility Classes */
.text-shadow {
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.bg-gradient {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
}

.border-accent {
    border-color: var(--accent-color) !important;
}

.hover-scale {
    transition: transform 0.3s ease;
}

.hover-scale:hover {
    transform: scale(1.05);
}

/* Print Styles */
@media print {
    .navbar,
    .offcanvas,
    .admob-banner,
    .adsbygoogle,
    footer {
        display: none !important;
    }
    
    .hero-section {
        background: white !important;
        color: black !important;
        min-height: auto;
        padding: 2rem 0;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid #ddd;
    }
    
    .btn {
        display: none;
    }
}

/* Accessibility Improvements */
.btn:focus,
.form-control:focus,
.form-select:focus {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

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

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
    .card {
        border: 2px solid var(--text-color);
    }
    
    .btn {
        border: 2px solid currentColor;
    }
}

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