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

:root {
    /* Color Palette */
    --primary-color: #D4AC0D;
    --secondary-color: #8D8741;
    --accent-color: #659DBD;
    --warm-color: #DAAD86;
    --light-color: #FBEEC1;
    
    /* Theme Colors */
    --background-color: #ffffff;
    --surface-color: #f8f9fa;
    --text-primary: #2c3e50;
    --text-secondary: #5a6c7d;
    --border-color: #e1e8ed;
    --shadow-color: rgba(0, 0, 0, 0.1);
    
    /* Typography */
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 2rem;
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 var(--shadow-color);
    --shadow-md: 0 4px 6px -1px var(--shadow-color);
    --shadow-lg: 0 10px 15px -3px var(--shadow-color);
    
    /* Transitions */
    --transition-fast: 0.15s ease-in-out;
    --transition-normal: 0.3s ease-in-out;
    --transition-slow: 0.5s ease-in-out;
}

/* Dark Theme */
[data-theme="dark"] {
    --background-color: #1a1a1a;
    --surface-color: #2d2d2d;
    --text-primary: #ffffff;
    --text-secondary: #b0b0b0;
    --border-color: #404040;
    --shadow-color: rgba(0, 0, 0, 0.3);
}

/* Base Styles */
html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--background-color);
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* Loading Screen */
.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    transition: opacity var(--transition-slow);
}

.loading-screen.hidden {
    opacity: 0;
    pointer-events: none;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: var(--spacing-md);
}

.loading-screen p {
    color: white;
    font-size: var(--font-size-lg);
    font-weight: 500;
}

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

/* Header */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: var(--spacing-xl) 0;
    position: relative;
    overflow: hidden;
}

.header::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 0 100 100"><defs><pattern id="grid" width="10" height="10" patternUnits="userSpaceOnUse"><path d="M 10 0 L 0 0 0 10" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="1"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
    opacity: 0.3;
}

.header__title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
    position: relative;
    z-index: 1;
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.header__icon {
    font-size: 2.5rem;
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateY(0); }
    40% { transform: translateY(-10px); }
    60% { transform: translateY(-5px); }
}

.header__subtitle {
    font-size: var(--font-size-lg);
    opacity: 0.9;
    position: relative;
    z-index: 1;
}

/* Theme Toggle */
.theme-toggle {
    position: absolute;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    background: rgba(255, 255, 255, 0.2);
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    z-index: 2;
}

.theme-toggle:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.1);
}

.theme-toggle__icon {
    font-size: var(--font-size-xl);
    transition: transform var(--transition-normal);
}

[data-theme="dark"] .theme-toggle__icon {
    transform: rotate(180deg);
}

/* Progress Bar */
.progress-bar {
    margin: var(--spacing-xl) 0;
    background: var(--surface-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    position: relative;
    overflow: hidden;
}

.progress-bar__fill {
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    border-radius: var(--radius-lg);
    transition: width var(--transition-slow);
    opacity: 0.1;
}

.progress-bar__steps {
    display: flex;
    justify-content: space-between;
    position: relative;
    z-index: 1;
}

.progress-step {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    flex: 1;
    position: relative;
}

.progress-step::after {
    content: '';
    position: absolute;
    top: 20px;
    left: 50%;
    width: 100%;
    height: 2px;
    background: var(--border-color);
    z-index: -1;
}

.progress-step:last-child::after {
    display: none;
}

.step-number {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--border-color);
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    transition: all var(--transition-normal);
}

.step-label {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    text-align: center;
    transition: color var(--transition-normal);
}

.progress-step.active .step-number {
    background: var(--primary-color);
    color: white;
    transform: scale(1.1);
}

.progress-step.active .step-label {
    color: var(--primary-color);
    font-weight: 600;
}

.progress-step.completed .step-number {
    background: var(--accent-color);
    color: white;
}

.progress-step.completed .step-label {
    color: var(--accent-color);
}

/* Form Styles */
.calculator-form {
    background: var(--surface-color);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow-lg);
    margin-bottom: var(--spacing-2xl);
}

.form-step {
    display: none;
    animation: fadeInUp 0.5s ease-out;
}

.form-step.active {
    display: block;
}

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

.step-header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.step-header h2 {
    font-size: var(--font-size-2xl);
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
}

.step-header p {
    color: var(--text-secondary);
    font-size: var(--font-size-lg);
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

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

.form-group label {
    font-weight: 600;
    color: var(--text-primary);
    font-size: var(--font-size-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-group input,
.form-group select {
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    background: var(--background-color);
    color: var(--text-primary);
    transition: all var(--transition-normal);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(212, 172, 13, 0.1);
}

.form-help {
    font-size: var(--font-size-xs);
    color: var(--text-secondary);
    font-style: italic;
}

/* Materials Section */
.materials-section {
    margin-bottom: var(--spacing-xl);
}

.materials-grid {
    display: grid;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.material-item {
    background: var(--background-color);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    position: relative;
    transition: all var(--transition-normal);
}

.material-item:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
}

.material-header {
    display: flex;
    justify-content: between;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.material-name {
    font-weight: 600;
    color: var(--text-primary);
    font-size: var(--font-size-lg);
}

.material-remove {
    background: #e74c3c;
    color: white;
    border: none;
    border-radius: 50%;
    width: 30px;
    height: 30px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-normal);
}

.material-remove:hover {
    background: #c0392b;
    transform: scale(1.1);
}

.material-fields {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-md);
}

/* Labor Section */
.labor-section {
    margin-bottom: var(--spacing-xl);
}

.labor-professionals {
    margin: var(--spacing-lg) 0;
}

.professional-item {
    background: var(--background-color);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    transition: all var(--transition-normal);
}

.professional-item:hover {
    border-color: var(--accent-color);
    box-shadow: var(--shadow-md);
}

/* Services Section */
.services-section {
    margin-bottom: var(--spacing-xl);
}

.services-grid {
    display: grid;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.service-item {
    background: var(--background-color);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    position: relative;
    transition: all var(--transition-normal);
}

.service-item:hover {
    border-color: var(--warm-color);
    box-shadow: var(--shadow-md);
}

/* Buttons */
.btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    text-decoration: none;
    text-align: center;
    justify-content: center;
    min-width: 120px;
}

.btn--primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
}

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

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

.btn--secondary:hover {
    background: #5a8db0;
    transform: translateY(-2px);
}

.btn--outline {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

.btn--outline:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.btn-icon {
    font-size: var(--font-size-lg);
}

/* Step Actions */
.step-actions {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-2xl);
    padding-top: var(--spacing-xl);
    border-top: 1px solid var(--border-color);
}

/* Results Section */
.results-section {
    text-align: center;
}

.cost-summary {
    background: var(--background-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-md);
}

.cost-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) 0;
    border-bottom: 1px solid var(--border-color);
}

.cost-item:last-child {
    border-bottom: none;
    font-weight: 700;
    font-size: var(--font-size-lg);
    color: var(--primary-color);
}

.cost-label {
    font-weight: 600;
    color: var(--text-primary);
}

.cost-value {
    font-weight: 600;
    color: var(--accent-color);
}

.cost-chart-container {
    margin: var(--spacing-xl) 0;
    display: flex;
    justify-content: center;
}

.results-actions {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    justify-content: center;
    margin: var(--spacing-xl) 0;
}

/* History Section */
.history-section {
    background: var(--surface-color);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    margin-bottom: var(--spacing-2xl);
    box-shadow: var(--shadow-md);
}

.history-section h2 {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    color: var(--text-primary);
}

.history-list {
    display: grid;
    gap: var(--spacing-lg);
}

.history-item {
    background: var(--background-color);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    transition: all var(--transition-normal);
    cursor: pointer;
}

.history-item:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
}

.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.history-title {
    font-weight: 600;
    color: var(--text-primary);
}

.history-date {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
}

.history-summary {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-md);
}

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

.history-cost-label {
    font-size: var(--font-size-xs);
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.history-cost-value {
    font-weight: 600;
    color: var(--accent-color);
    font-size: var(--font-size-lg);
}

/* FAQ Section */
.faq-section {
    background: var(--surface-color);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    margin-bottom: var(--spacing-2xl);
    box-shadow: var(--shadow-md);
}

.faq-section h2 {
    text-align: center;
    margin-bottom: var(--spacing-xl);
    color: var(--text-primary);
}

.faq-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.faq-item {
    background: var(--background-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

.faq-item:hover {
    box-shadow: var(--shadow-md);
}

.faq-question {
    width: 100%;
    padding: var(--spacing-lg);
    background: none;
    border: none;
    text-align: left;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: var(--font-size-base);
    font-weight: 600;
    color: var(--text-primary);
    transition: all var(--transition-normal);
}

.faq-question:hover {
    background: var(--light-color);
}

.faq-icon {
    font-size: var(--font-size-xl);
    font-weight: 300;
    transition: transform var(--transition-normal);
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 var(--spacing-lg);
    max-height: 0;
    overflow: hidden;
    transition: all var(--transition-normal);
}

.faq-item.active .faq-answer {
    padding: var(--spacing-lg);
    max-height: 200px;
}

.faq-answer p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Footer */
.footer {
    background: var(--text-primary);
    color: darkgray;
    text-align: center;
    padding: var(--spacing-xl) 0;
    margin-top: var(--spacing-2xl);
}

.footer__text {
    opacity: 1;
}

.footer__text a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-normal);
}

.footer__text a:hover {
    color: var(--light-color);
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    z-index: 10000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.toast {
    background: var(--background-color);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: var(--spacing-md) var(--spacing-lg);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    min-width: 300px;
    animation: slideInRight 0.3s ease-out;
    transition: all var(--transition-normal);
}

.toast.success {
    border-color: #27ae60;
    background: #d5f4e6;
}

.toast.error {
    border-color: #e74c3c;
    background: #fdf2f2;
}

.toast.warning {
    border-color: #f39c12;
    background: #fef9e7;
}

.toast.info {
    border-color: var(--accent-color);
    background: var(--light-color);
}

@keyframes slideInRight {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Modal */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10000;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--background-color);
    border-radius: var(--radius-xl);
    max-width: 90vw;
    max-height: 90vh;
    width: 500px;
    box-shadow: var(--shadow-lg);
    transform: scale(0.9);
    transition: transform var(--transition-normal);
    overflow: hidden;
}

.modal-overlay.active .modal {
    transform: scale(1);
}

.modal-header {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    color: var(--text-primary);
    font-size: var(--font-size-xl);
}

.modal-close {
    background: none;
    border: none;
    font-size: var(--font-size-2xl);
    cursor: pointer;
    color: var(--text-secondary);
    transition: color var(--transition-normal);
}

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

.modal-content {
    padding: var(--spacing-lg);
    max-height: 60vh;
    overflow-y: auto;
}

.modal-actions {
    padding: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .header__title {
        font-size: var(--font-size-2xl);
        text-align: center;
    }
    
    .theme-toggle {
        position: static;
        margin: var(--spacing-md) auto 0;
    }
    
    .progress-bar__steps {
        flex-wrap: wrap;
        gap: var(--spacing-md);
    }
    
    .progress-step {
        flex: 1 1 calc(50% - var(--spacing-md));
        min-width: 120px;
    }
    
    .form-grid {
        grid-template-columns: 1fr;
    }
    
    .step-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .results-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .toast-container {
        left: var(--spacing-sm);
        right: var(--spacing-sm);
    }
    
    .toast {
        min-width: auto;
    }
    
    .modal {
        width: 95vw;
        margin: var(--spacing-md);
    }
}

@media (max-width: 480px) {
    .header {
        padding: var(--spacing-lg) 0;
    }
    
    .header__title {
        font-size: var(--font-size-xl);
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .calculator-form {
        padding: var(--spacing-lg);
    }
    
    .step-header h2 {
        font-size: var(--font-size-xl);
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .progress-step {
        flex: 1 1 100%;
    }
    
    .progress-step::after {
        display: none;
    }
}

/* Print Styles */
@media print {
    .header,
    .progress-bar,
    .step-actions,
    .results-actions,
    .footer,
    .theme-toggle {
        display: none;
    }
    
    .calculator-form {
        box-shadow: none;
        border: 1px solid #000;
    }
    
    .form-step {
        display: block !important;
        page-break-after: always;
    }
    
    .form-step:last-child {
        page-break-after: auto;
    }
}

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

/* Focus styles for keyboard navigation */
button:focus,
input:focus,
select:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000000;
        --shadow-color: rgba(0, 0, 0, 0.5);
    }
}