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

:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --background-color: #ecf0f1;
    --error-color: #e74c3c;
    --success-color: #2ecc71;
    --text-dark: #2c3e50;
    --text-light: #7f8c8d;
    --border-radius: 12px;
    --shadow: 0 2px 12px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--background-color);
    color: var(--text-dark);
    line-height: 1.6;
    padding-bottom: 80px;
}

/* Header Styles */
.app-header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    text-align: center;
    padding: 1.5rem 1rem;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.app-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.app-header p {
    font-size: 0.9rem;
    opacity: 0.9;
    font-weight: 300;
}

/* Main Content */
.app-main {
    padding: 1rem;
    max-width: 1200px;
    margin: 0 auto;
}

/* Section Management */
.section {
    display: none;
    animation: fadeIn 0.3s ease-in-out;
}

.section.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Search Container */
.search-container {
    background: white;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow);
    position: relative;
}

.search-box {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

#searchInput {
    flex: 1;
    padding: 1rem;
    border: 2px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

#searchInput:focus {
    outline: none;
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

.search-btn {
    padding: 1rem 1.5rem;
    background: var(--secondary-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-size: 1rem;
}

.search-btn:hover {
    background: #2980b9;
    transform: translateY(-2px);
}

.search-btn:active {
    transform: translateY(0);
}

/* Suggestions */
.suggestions-container {
    position: absolute;
    top: 100%;
    left: 1.5rem;
    right: 1.5rem;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    z-index: 50;
    max-height: 300px;
    overflow-y: auto;
    display: none;
}

.suggestions-container.show {
    display: block;
}

.suggestion-item {
    padding: 1rem;
    cursor: pointer;
    border-bottom: 1px solid #f0f0f0;
    transition: var(--transition);
}

.suggestion-item:hover {
    background: #f8f9fa;
}

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

.suggestion-code {
    font-weight: 600;
    color: var(--secondary-color);
    margin-bottom: 0.25rem;
}

.suggestion-desc {
    font-size: 0.9rem;
    color: var(--text-light);
}

/* Converter Section */
.converter-section {
    background: white;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow);
}

.converter-section h2 {
    margin-bottom: 1.5rem;
    color: var(--primary-color);
    font-size: 1.25rem;
}

.converter-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

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

.converter-item label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.converter-item input {
    width: 100%;
    padding: 1rem;
    border: 2px solid #ddd;
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
}

.converter-item input:focus {
    outline: none;
    border-color: var(--secondary-color);
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.1);
}

.convert-btn {
    width: 100%;
    padding: 1rem;
    background: var(--success-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.convert-btn:hover {
    background: #27ae60;
    transform: translateY(-2px);
}

.convert-btn:active {
    transform: translateY(0);
}

/* Results Container */
.results-container {
    background: white;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow);
    display: none;
}

.results-container.show {
    display: block;
}

.result-item {
    border: 2px solid #f0f0f0;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: var(--transition);
    position: relative;
}

.result-item:hover {
    border-color: var(--secondary-color);
    transform: translateY(-2px);
}

.result-item:last-child {
    margin-bottom: 0;
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.result-code {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
}

.result-type {
    background: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
}

.result-description {
    font-size: 1rem;
    color: var(--text-dark);
    margin-bottom: 1rem;
    line-height: 1.5;
}

.result-actions {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.action-btn {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.favorite-btn {
    background: #f39c12;
    color: white;
}

.favorite-btn.active {
    background: #e67e22;
}

.favorite-btn:hover {
    background: #e67e22;
    transform: translateY(-1px);
}

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

.share-btn:hover {
    background: #2980b9;
    transform: translateY(-1px);
}

/* Related Codes */
.related-codes {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid #eee;
}

.related-codes h4 {
    margin-bottom: 0.75rem;
    color: var(--primary-color);
    font-size: 1rem;
}

.related-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.related-item {
    background: #f8f9fa;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    color: var(--text-dark);
    cursor: pointer;
    transition: var(--transition);
}

.related-item:hover {
    background: var(--secondary-color);
    color: white;
}

/* Favorites Section */
.favorites-list {
    display: grid;
    gap: 1rem;
}

/* History Section */
.history-actions {
    margin-bottom: 1.5rem;
    text-align: right;
}

.clear-btn {
    padding: 0.75rem 1.5rem;
    background: var(--error-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 0.9rem;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.clear-btn:hover {
    background: #c0392b;
    transform: translateY(-2px);
}

.history-list {
    display: grid;
    gap: 1rem;
}

.history-item {
    background: white;
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    border-left: 4px solid var(--secondary-color);
}

.history-timestamp {
    font-size: 0.8rem;
    color: var(--text-light);
    margin-bottom: 0.5rem;
}

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

.history-results {
    font-size: 0.9rem;
    color: var(--text-light);
}

/* FAQ Section */
.faq-container {
    display: grid;
    gap: 1rem;
}

.faq-item {
    background: white;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 1.5rem;
    background: none;
    border: none;
    text-align: left;
    font-size: 1rem;
    font-weight: 600;
    color: var(--primary-color);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.faq-question:hover {
    background: #f8f9fa;
}

.faq-question[aria-expanded="true"] {
    background: var(--secondary-color);
    color: white;
}

.faq-icon {
    font-size: 1.25rem;
    transition: var(--transition);
}

.faq-question[aria-expanded="true"] .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    padding: 0 1.5rem;
    max-height: 0;
    overflow: hidden;
    transition: all 0.3s ease-in-out;
}

.faq-answer.show {
    padding: 1.5rem;
    max-height: 500px;
}

.faq-answer p {
    margin-bottom: 1rem;
    color: var(--text-dark);
    line-height: 1.6;
}

.faq-answer ul {
    margin-left: 1.5rem;
    margin-bottom: 1rem;
}

.faq-answer li {
    margin-bottom: 0.5rem;
}

.faq-answer a {
    color: var(--secondary-color);
    text-decoration: none;
}

.faq-answer a:hover {
    text-decoration: underline;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-light);
}

.empty-state i {
    font-size: 3rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state p {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.empty-state small {
    font-size: 0.9rem;
}

/* Bottom Navigation */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: white;
    display: flex;
    justify-content: space-around;
    padding: 0.75rem 0;
    box-shadow: 0 -2px 12px rgba(0, 0, 0, 0.1);
    z-index: 100;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-decoration: none;
    color: var(--text-light);
    font-size: 0.8rem;
    transition: var(--transition);
    padding: 0.5rem;
    border-radius: 8px;
    min-width: 60px;
}

.nav-item i {
    font-size: 1.25rem;
    margin-bottom: 0.25rem;
}

.nav-item.active {
    color: var(--secondary-color);
    background: rgba(52, 152, 219, 0.1);
}

.nav-item:hover {
    color: var(--secondary-color);
    transform: translateY(-2px);
}

/* Footer */
.app-footer {
    text-align: center;
    padding: 2rem 1rem;
    background: var(--primary-color);
    color: white;
    font-size: 0.9rem;
    margin-top: 2rem;
}

.app-footer a {
    color: var(--secondary-color);
    text-decoration: none;
}

.app-footer a:hover {
    text-decoration: underline;
}

/* Loading Indicator */
.loading-indicator {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.9);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.loading-indicator[hidden] {
    display: none !important;
}

.loading-indicator {
    display: none;
}

.loading-indicator:not([hidden]) {
    display: flex !important;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid var(--secondary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 1rem;
}

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

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: 100px;
    right: 1rem;
    z-index: 1000;
}

.toast {
    background: var(--primary-color);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: var(--border-radius);
    margin-bottom: 0.5rem;
    box-shadow: var(--shadow);
    animation: slideIn 0.3s ease-in-out;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    max-width: 300px;
}

.toast.success {
    background: var(--success-color);
}

.toast.error {
    background: var(--error-color);
}

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

/* Responsive Design */
@media (min-width: 768px) {
    .app-main {
        padding: 2rem;
    }
    
    .search-container,
    .converter-section {
        padding: 2rem;
    }
    
    .bottom-nav {
        position: relative;
        box-shadow: none;
        background: transparent;
        justify-content: center;
        gap: 2rem;
        padding: 1rem 0;
    }
    
    body {
        padding-bottom: 0;
    }
    
    .nav-item {
        background: white;
        box-shadow: var(--shadow);
        padding: 1rem 1.5rem;
        border-radius: var(--border-radius);
        min-width: auto;
    }
    
    .nav-item.active {
        background: var(--secondary-color);
        color: white;
    }
}

@media (min-width: 1024px) {
    .results-container {
        padding: 2rem;
    }
    
    .result-item {
        padding: 2rem;
    }
    
    .favorites-list,
    .history-list {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .faq-container {
        grid-template-columns: 1fr;
        max-width: 800px;
        margin: 0 auto;
    }
}

/* Print Styles */
@media print {
    .bottom-nav,
    .search-container,
    .converter-section {
        display: none;
    }
    
    .results-container {
        box-shadow: none;
        border: 1px solid #ddd;
    }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
    :root {
        --primary-color: #000;
        --secondary-color: #0066cc;
        --background-color: #fff;
        --text-dark: #000;
        --text-light: #333;
    }
}

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

/* Dark Mode Support */
@media (prefers-color-scheme: dark) {
    :root {
        --primary-color: #34495e;
        --secondary-color: #5dade2;
        --background-color: #2c3e50;
        --text-dark: #ecf0f1;
        --text-light: #bdc3c7;
    }
    
    body {
        background-color: #2c3e50;
        color: #ecf0f1;
    }
    
    .search-container,
    .converter-section,
    .result-item,
    .faq-item,
    .history-item {
        background: #34495e;
        color: #ecf0f1;
    }
    
    .bottom-nav {
        background: #34495e;
        border-top: 1px solid #4a5f7a;
    }
    
    input {
        background: #4a5f7a;
        color: #ecf0f1;
        border-color: #5a6f8a;
    }
    
    input:focus {
        border-color: var(--secondary-color);
    }
}