:root {
    /* Light Mode Colors */
    --primary-light: #28124C;
    --secondary-light: #328553;
    --accent-light: #854FBC;
    --highlight-light: #DFB6B2;
    --background-light: #FBE4D8;
    --text-light: #190019;
    --card-light: #FFFFFF;
    
    /* Dark Mode Colors */
    --primary-dark: #854FBC;
    --secondary-dark: #328553;
    --accent-dark: #DFB6B2;
    --highlight-dark: #28124C;
    --background-dark: #190019;
    --text-dark: #FBE4D8;
    --card-dark: #28124C;
    
    /* Common */
    --border-radius: 8px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: var(--background-light);
    color: var(--text-light);
    line-height: 1.6;
    transition: var(--transition);
}

body.dark-mode {
    background-color: var(--background-dark);
    color: var(--text-dark);
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Header Styles */
header {
    background-color: var(--primary-light);
    color: var(--background-light);
    padding: 30px 0;
    margin-bottom: 20px;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.dark-mode header {
    background-color: var(--primary-dark);
}

.header-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.theme-toggle {
    display: flex;
    align-items: center;
    gap: 10px;
}

.theme-icon {
    font-size: 1.2rem;
}

.switch {
    position: relative;
    display: inline-block;
    width: 60px;
    height: 34px;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--accent-light);
    transition: .4s;
    border-radius: 34px;
}

.dark-mode .slider {
    background-color: var(--accent-dark);
}

.slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: .4s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: var(--secondary-light);
}

input:checked + .slider:before {
    transform: translateX(26px);
}

/* Navigation */
nav {
    background-color: var(--secondary-light);
    margin-bottom: 30px;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.dark-mode nav {
    background-color: var(--secondary-dark);
}

nav ul {
    display: flex;
    list-style: none;
}

nav li {
    flex: 1;
    text-align: center;
}

nav a {
    display: block;
    padding: 15px 10px;
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

nav a:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

nav a.active {
    background-color: var(--highlight-light);
    font-weight: bold;
}

.dark-mode nav a.active {
    background-color: var(--highlight-dark);
}

/* Content Sections */
.content-section {
    display: none;
    animation: fadeIn 0.5s ease;
}

.content-section.active-section {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Problem Solver Section */
.problem-input, .solution-section, .history-section, 
.practice-problem, .progress-tracker, .category-card,
.graphing-container {
    background-color: var(--card-light);
    padding: 25px;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    margin-bottom: 30px;
    transition: var(--transition);
}

.dark-mode .problem-input, 
.dark-mode .solution-section, 
.dark-mode .history-section,
.dark-mode .practice-problem, 
.dark-mode .progress-tracker, 
.dark-mode .category-card,
.dark-mode .graphing-container {
    background-color: var(--card-dark);
}

.problem-input h2, .solution-section h2, 
.history-section h2, .practice-header h2,
.reference-library h2, .graphing-tool h2 {
    color: var(--primary-light);
    margin-bottom: 20px;
}

.dark-mode .problem-input h2, 
.dark-mode .solution-section h2, 
.dark-mode .history-section h2,
.dark-mode .practice-header h2,
.dark-mode .reference-library h2, 
.dark-mode .graphing-tool h2 {
    color: var(--primary-dark);
}

.input-options {
    display: flex;
    margin-bottom: 15px;
    gap: 10px;
}

.input-options button {
    padding: 10px 20px;
    border: none;
    background-color: var(--highlight-light);
    color: var(--text-light);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
    border-radius: var(--border-radius);
}

.dark-mode .input-options button {
    background-color: var(--highlight-dark);
    color: var(--text-dark);
}

.input-options button.active {
    background-color: var(--primary-light);
    color: white;
}

.dark-mode .input-options button.active {
    background-color: var(--primary-dark);
}

#problem-text {
    width: 100%;
    min-height: 120px;
    padding: 15px;
    border: 1px solid var(--highlight-light);
    border-radius: var(--border-radius);
    font-size: 1rem;
    resize: vertical;
    margin-bottom: 15px;
    background-color: var(--background-light);
    color: var(--text-light);
    transition: var(--transition);
}

.dark-mode #problem-text {
    border-color: var(--highlight-dark);
    background-color: var(--background-dark);
    color: var(--text-dark);
}

.voice-status {
    font-style: italic;
    color: var(--secondary-light);
    margin-bottom: 15px;
}

.dark-mode .voice-status {
    color: var(--secondary-dark);
}

#image-input-container {
    margin-bottom: 15px;
}

#problem-image {
    margin-bottom: 15px;
}

.image-preview {
    width: 100%;
    max-height: 300px;
    border: 2px dashed var(--highlight-light);
    border-radius: var(--border-radius);
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    transition: var(--transition);
}

.dark-mode .image-preview {
    border-color: var(--highlight-dark);
}

.image-preview img {
    max-width: 100%;
    max-height: 100%;
}

.controls {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

#problem-type {
    flex: 1;
    min-width: 200px;
    padding: 10px;
    border: 1px solid var(--highlight-light);
    border-radius: var(--border-radius);
    font-size: 1rem;
    background-color: var(--background-light);
    color: var(--text-light);
    transition: var(--transition);
}

.dark-mode #problem-type {
    border-color: var(--highlight-dark);
    background-color: var(--background-dark);
    color: var(--text-dark);
}

#solve-btn, #multiple-methods-btn, #generate-practice,
#show-hint, #show-solution, #new-problem, #search-btn,
.add-function, #add-more-functions, #update-graph,
#save-graph, .export-buttons button {
    padding: 10px 25px;
    background-color: var(--primary-light);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    transition: var(--transition);
}

.dark-mode #solve-btn, 
.dark-mode #multiple-methods-btn, 
.dark-mode #generate-practice,
.dark-mode #show-hint, 
.dark-mode #show-solution, 
.dark-mode #new-problem,
.dark-mode #search-btn,
.dark-mode .add-function, 
.dark-mode #add-more-functions, 
.dark-mode #update-graph,
.dark-mode #save-graph,
.dark-mode .export-buttons button {
    background-color: var(--primary-dark);
}

#solve-btn:hover, #multiple-methods-btn:hover, #generate-practice:hover,
#show-hint:hover, #show-solution:hover, #new-problem:hover, #search-btn:hover,
.add-function:hover, #add-more-functions:hover, #update-graph:hover,
#save-graph:hover, .export-buttons button:hover {
    background-color: var(--accent-light);
}

.dark-mode #solve-btn:hover, 
.dark-mode #multiple-methods-btn:hover, 
.dark-mode #generate-practice:hover,
.dark-mode #show-hint:hover, 
.dark-mode #show-solution:hover, 
.dark-mode #new-problem:hover,
.dark-mode #search-btn:hover,
.dark-mode .add-function:hover, 
.dark-mode #add-more-functions:hover, 
.dark-mode #update-graph:hover,
.dark-mode #save-graph:hover,
.dark-mode .export-buttons button:hover {
    background-color: var(--accent-dark);
}

.loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 30px;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 5px solid var(--highlight-light);
    border-top: 5px solid var(--primary-light);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 15px;
    transition: var(--transition);
}

.dark-mode .spinner {
    border-color: var(--highlight-dark);
    border-top-color: var(--primary-dark);
}

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

.solution-tabs {
    display: flex;
    border-bottom: 1px solid var(--highlight-light);
    margin-bottom: 20px;
    flex-wrap: wrap;
    transition: var(--transition);
}

.dark-mode .solution-tabs {
    border-bottom-color: var(--highlight-dark);
}

.tab-btn {
    padding: 10px 20px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    color: var(--secondary-light);
    position: relative;
    transition: var(--transition);
}

.dark-mode .tab-btn {
    color: var(--secondary-dark);
}

.tab-btn.active {
    color: var(--primary-light);
    font-weight: bold;
}

.dark-mode .tab-btn.active {
    color: var(--primary-dark);
}

.tab-btn.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--primary-light);
}

.dark-mode .tab-btn.active::after {
    background-color: var(--primary-dark);
}

.export-buttons {
    margin-left: auto;
    display: flex;
    gap: 10px;
}

.tab-content {
    display: none;
}

.tab-content.active-tab {
    display: block;
}

.final-answer {
    margin-bottom: 25px;
    padding: 15px;
    background-color: var(--highlight-light);
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.dark-mode .final-answer {
    background-color: var(--highlight-dark);
}

.final-answer h3 {
    margin-bottom: 10px;
    color: var(--secondary-light);
}

.dark-mode .final-answer h3 {
    color: var(--secondary-dark);
}

.math-display {
    font-size: 1.2rem;
    padding: 10px;
    background-color: var(--background-light);
    border-radius: var(--border-radius);
    overflow-x: auto;
    transition: var(--transition);
}

.dark-mode .math-display {
    background-color: var(--background-dark);
}

.step-by-step h3 {
    margin-bottom: 15px;
    color: var(--primary-light);
}

.dark-mode .step-by-step h3 {
    color: var(--primary-dark);
}

.step {
    margin-bottom: 15px;
    padding: 15px;
    background-color: var(--highlight-light);
    border-radius: var(--border-radius);
    border-left: 4px solid var(--primary-light);
    transition: var(--transition);
}

.dark-mode .step {
    background-color: var(--highlight-dark);
    border-left-color: var(--primary-dark);
}

.step-number {
    font-weight: bold;
    color: var(--primary-light);
    margin-bottom: 5px;
}

.dark-mode .step-number {
    color: var(--primary-dark);
}

.alternative-method {
    margin-bottom: 20px;
    padding: 15px;
    background-color: var(--highlight-light);
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.dark-mode .alternative-method {
    background-color: var(--highlight-dark);
}

.alternative-method h4 {
    color: var(--accent-light);
    margin-bottom: 10px;
}

.dark-mode .alternative-method h4 {
    color: var(--accent-dark);
}

.graph-container {
    width: 100%;
    height: 400px;
    margin-top: 20px;
}

/* History Section */
.history-item {
    padding: 15px;
    margin-bottom: 10px;
    background-color: var(--highlight-light);
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
}

.dark-mode .history-item {
    background-color: var(--highlight-dark);
}

.history-item:hover {
    background-color: var(--accent-light);
    color: white;
}

.dark-mode .history-item:hover {
    background-color: var(--accent-dark);
}

.history-problem {
    font-weight: 500;
    margin-bottom: 5px;
}

.history-answer {
    color: var(--secondary-light);
    font-style: italic;
    margin-bottom: 5px;
}

.dark-mode .history-answer {
    color: var(--secondary-dark);
}

.history-date {
    font-size: 0.8rem;
    color: var(--text-light);
    opacity: 0.7;
}

.dark-mode .history-date {
    color: var(--text-dark);
}

/* Practice Mode Section */
.practice-controls {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.practice-controls select {
    flex: 1;
    min-width: 200px;
    padding: 10px;
    border: 1px solid var(--highlight-light);
    border-radius: var(--border-radius);
    font-size: 1rem;
    background-color: var(--background-light);
    color: var(--text-light);
    transition: var(--transition);
}

.dark-mode .practice-controls select {
    border-color: var(--highlight-dark);
    background-color: var(--background-dark);
    color: var(--text-dark);
}

#practice-problem-text {
    margin-bottom: 20px;
    font-size: 1.2rem;
}

.practice-actions {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
}

.hidden {
    display: none;
}

#practice-hint, #practice-solution {
    padding: 15px;
    background-color: var(--highlight-light);
    border-radius: var(--border-radius);
    margin-bottom: 15px;
    transition: var(--transition);
}

.dark-mode #practice-hint, 
.dark-mode #practice-solution {
    background-color: var(--highlight-dark);
}

#practice-hint h4, #practice-solution h4 {
    color: var(--primary-light);
    margin-bottom: 10px;
}

.dark-mode #practice-hint h4, 
.dark-mode #practice-solution h4 {
    color: var(--primary-dark);
}

.progress-tracker h3 {
    margin-bottom: 20px;
    color: var(--primary-light);
}

.dark-mode .progress-tracker h3 {
    color: var(--primary-dark);
}

.progress-item {
    margin-bottom: 15px;
}

.progress-item label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

.progress-bar {
    width: 100%;
    height: 20px;
    background-color: var(--highlight-light);
    border-radius: 10px;
    overflow: hidden;
    transition: var(--transition);
}

.dark-mode .progress-bar {
    background-color: var(--highlight-dark);
}

.progress-fill {
    height: 100%;
    background-color: var(--secondary-light);
    border-radius: 10px;
    transition: width 0.5s ease;
}

.dark-mode .progress-fill {
    background-color: var(--secondary-dark);
}

/* Reference Library Section */
.search-box {
    display: flex;
    gap: 15px;
    margin-bottom: 20px;
}

#reference-search {
    flex: 1;
    padding: 10px 15px;
    border: 1px solid var(--highlight-light);
    border-radius: var(--border-radius);
    font-size: 1rem;
    background-color: var(--background-light);
    color: var(--text-light);
    transition: var(--transition);
}

.dark-mode #reference-search {
    border-color: var(--highlight-dark);
    background-color: var(--background-dark);
    color: var(--text-dark);
}

.reference-categories {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

.category-card h3 {
    color: var(--primary-light);
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--highlight-light);
}

.dark-mode .category-card h3 {
    color: var(--primary-dark);
    border-bottom-color: var(--highlight-dark);
}

.formula-item {
    margin-bottom: 15px;
    padding: 10px;
    background-color: var(--highlight-light);
    border-radius: var(--border-radius);
    transition: var(--transition);
}

.dark-mode .formula-item {
    background-color: var(--highlight-dark);
}

.formula-item h4 {
    color: var(--accent-light);
    margin-bottom: 5px;
}

.dark-mode .formula-item h4 {
    color: var(--accent-dark);
}

.formula-item p {
    margin-bottom: 5px;
}

/* Graphing Tool Section */
.graphing-container {
    display: flex;
    flex-direction: column;
}

.graph-controls {
    margin-bottom: 20px;
}

.function-inputs {
    margin-bottom: 15px;
}

.function-input {
    display: flex;
    gap: 10px;
    margin-bottom: 10px;
    align-items: center;
}

.function-expression {
    flex: 1;
    padding: 10px;
    border: 1px solid var(--highlight-light);
    border-radius: var(--border-radius);
    background-color: var(--background-light);
    color: var(--text-light);
    transition: var(--transition);
}

.dark-mode .function-expression {
    border-color: var(--highlight-dark);
    background-color: var(--background-dark);
    color: var(--text-dark);
}

.function-color {
    width: 40px;
    height: 40px;
    border: none;
    cursor: pointer;
}

.graph-settings {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    margin-top: 15px;
}

.graph-settings label {
    display: flex;
    align-items: center;
    gap: 5px;
}

.graph-settings input[type="number"] {
    width: 60px;
    padding: 5px;
    border: 1px solid var(--highlight-light);
    border-radius: var(--border-radius);
    background-color: var(--background-light);
    color: var(--text-light);
    transition: var(--transition);
}

.dark-mode .graph-settings input[type="number"] {
    border-color: var(--highlight-dark);
    background-color: var(--background-dark);
    color: var(--text-dark);
}

.graph-display {
    width: 100%;
    height: 500px;
    border: 1px solid var(--highlight-light);
    border-radius: var(--border-radius);
    overflow: hidden;
    transition: var(--transition);
}

.dark-mode .graph-display {
    border-color: var(--highlight-dark);
}

/* Footer */
footer {
    background-color: var(--primary-light);
    color: white;
    padding: 40px 0 20px;
    margin-top: 50px;
    transition: var(--transition);
}

.dark-mode footer {
    background-color: var(--primary-dark);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 30px;
}

.footer-section h3 {
    margin-bottom: 15px;
    font-size: 1.2rem;
}

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

.footer-section li {
    margin-bottom: 8px;
}

.social-icons {
    display: flex;
    gap: 15px;
    margin-top: 15px;
}

.social-icons span {
    font-size: 1.5rem;
    cursor: pointer;
    transition: transform 0.3s;
}

.social-icons span:hover {
    transform: translateY(-3px);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* Responsive Design */
@media (max-width: 768px) {
    nav ul {
        flex-direction: column;
    }
    
    .header-top {
        flex-direction: column;
        gap: 15px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
    
    .controls, .practice-controls {
        flex-direction: column;
    }
    
    #problem-type, .practice-controls select {
        width: 100%;
    }
}