/* CSS Variables */
:root {
    --primary-bg: #0a0a1a;
    --secondary-bg: #1a1a2e;
    --accent-color: #00d4ff;
    --secondary-accent: #ff6b6b;
    --success-color: #51cf66;
    --warning-color: #ffd43b;
    --error-color: #ff6b6b;
    --text-color: #ffffff;
    --text-muted: #a0a0a0;
    --border-color: #2a2a3e;
    --card-bg: rgba(255, 255, 255, 0.05);
    --card-hover: rgba(255, 255, 255, 0.1);
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 12px 40px rgba(0, 0, 0, 0.4);
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-accent: linear-gradient(135deg, #00d4ff 0%, #0099cc 100%);
    --gradient-success: linear-gradient(135deg, #51cf66 0%, #40c057 100%);
    --border-radius: 12px;
    --border-radius-lg: 20px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark mode variables */
[data-theme="dark"] {
    --primary-bg: #0a0a1a;
    --secondary-bg: #1a1a2e;
    --text-color: #ffffff;
    --text-muted: #a0a0a0;
}

/* Light mode variables */
[data-theme="light"] {
    --primary-bg: #ffffff;
    --secondary-bg: #f8f9fa;
    --text-color: #1a1a2e;
    --text-muted: #6c757d;
    --card-bg: rgba(0, 0, 0, 0.05);
    --card-hover: rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: 'Inter', 'Montserrat', sans-serif;
    background: var(--primary-bg);
    color: var(--text-color);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.6;
    transition: var(--transition);
}

/* Utility Classes */
.hidden {
    display: none !important;
}

/* Error Notification */
.error-notification {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--error-color);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: var(--border-radius);
    z-index: 10000;
    max-width: 300px;
    box-shadow: var(--shadow);
    animation: slideInRight 0.3s ease;
    font-weight: 500;
}

/* Success Notification */
.success-notification {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--success-color);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: var(--border-radius);
    z-index: 10000;
    max-width: 300px;
    box-shadow: var(--shadow);
    animation: slideInRight 0.3s ease;
    font-weight: 500;
}

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

.page {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Loading Screen */
.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    animation: fadeIn 0.5s ease;
}

.loading-content {
    text-align: center;
    color: white;
}

.loading-logo {
    font-size: 4rem;
    margin-bottom: 1rem;
    animation: pulse 2s infinite;
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top: 4px solid white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 2rem auto;
}

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

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

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

/* Intro Page */
.intro-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 2rem;
    text-align: center;
    background: var(--gradient-primary);
    position: relative;
    overflow: hidden;
}

.intro-content::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="0.5"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
    opacity: 0.3;
}

.logo-container {
    position: relative;
    z-index: 2;
    margin-bottom: 3rem;
}

.logo {
    font-size: 5rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
    text-shadow: 0 0 20px rgba(0, 212, 255, 0.5);
}

.main-title {
    font-size: clamp(3rem, 8vw, 4.5rem);
    font-weight: 700;
    margin-bottom: 0.5rem;
    background: linear-gradient(45deg, #fff, var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    font-size: 1.5rem;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 3rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    max-width: 1000px;
    width: 100%;
    margin-bottom: 3rem;
}

.feature {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: var(--border-radius-lg);
    padding: 2rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: var(--transition);
}

.feature:hover {
    transform: translateY(-5px);
    background: rgba(255, 255, 255, 0.15);
}

.feature i {
    font-size: 2.5rem;
    color: var(--accent-color);
    margin-bottom: 1rem;
}

.feature h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
    color: white;
}

.feature p {
    color: rgba(255, 255, 255, 0.8);
}

/* Buttons */
.primary-btn {
    background: var(--gradient-accent);
    color: white;
    border: none;
    padding: 1rem 2.5rem;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    position: relative;
    z-index: 2;
}

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

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

.icon-btn {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
}

.icon-btn:hover {
    background: var(--card-hover);
    transform: scale(1.1);
}

/* Header */
.app-header {
    background: var(--secondary-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-small {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    font-size: 1.2rem;
    color: var(--accent-color);
}

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

/* Main Content */
.main-content {
    flex: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    width: 100%;
}

/* Category Tabs */
.category-tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 2rem;
    overflow-x: auto;
    padding-bottom: 0.5rem;
}

.category-tab {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
}

.category-tab:hover {
    background: var(--card-hover);
    color: var(--text-color);
}

.category-tab.active {
    background: var(--gradient-accent);
    color: white;
    border-color: var(--accent-color);
}

/* Conversion Grid */
.conversion-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 2rem;
}

.conversion-btn {
    background: var(--card-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    min-height: 120px;
    justify-content: center;
}

.conversion-btn:hover {
    border-color: var(--accent-color);
    background: var(--card-hover);
    transform: translateY(-2px);
}

.conversion-btn.active {
    border-color: var(--accent-color);
    background: rgba(0, 212, 255, 0.1);
    color: var(--accent-color);
}

.conversion-btn i {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.conversion-btn .btn-title {
    font-weight: 600;
    font-size: 0.9rem;
}

.conversion-btn .btn-subtitle {
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* Upload Section */
.upload-section {
    background: var(--card-bg);
    border: 2px dashed var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: 2rem;
    margin-bottom: 2rem;
    transition: var(--transition);
}

.upload-section.drag-over {
    border-color: var(--accent-color);
    background: rgba(0, 212, 255, 0.05);
}

.upload-area {
    text-align: center;
    padding: 2rem;
}

.upload-content i {
    font-size: 3rem;
    color: var(--accent-color);
    margin-bottom: 1rem;
}

.upload-content h3 {
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.upload-content p {
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}

#file-input {
    display: none;
}

.upload-btn {
    background: var(--gradient-accent);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
}

.upload-btn:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow);
}

/* File List */
.file-list {
    margin-top: 1rem;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: var(--secondary-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1rem;
    margin-bottom: 0.5rem;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex: 1;
}

.file-icon {
    font-size: 1.5rem;
    color: var(--accent-color);
}

.file-details h4 {
    font-size: 0.9rem;
    margin-bottom: 0.25rem;
}

.file-details p {
    font-size: 0.8rem;
    color: var(--text-muted);
}

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

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

.remove-file:hover {
    transform: scale(1.1);
}

/* Conversion Options */
.conversion-options {
    display: flex;
    gap: 1rem;
    margin: 1rem 0;
    flex-wrap: wrap;
}

.option-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.option-group label {
    font-weight: 500;
    color: var(--text-color);
}

.option-group select {
    background: var(--secondary-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 0.5rem;
    border-radius: var(--border-radius);
    min-width: 120px;
}

/* Convert Button */
.convert-btn {
    background: var(--gradient-success);
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    width: 100%;
    justify-content: center;
    margin-top: 1rem;
}

.convert-btn:hover:not(:disabled) {
    transform: translateY(-1px);
    box-shadow: var(--shadow);
}

.convert-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Text Input Section */
.text-input-section {
    background: var(--card-bg);
    border-radius: var(--border-radius-lg);
    padding: 2rem;
    margin-bottom: 2rem;
}

.text-input-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

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

.action-btn {
    background: var(--secondary-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
}

.action-btn:hover {
    background: var(--card-hover);
}

#text-input {
    width: 100%;
    min-height: 200px;
    background: var(--secondary-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 1rem;
    border-radius: var(--border-radius);
    resize: vertical;
    font-family: inherit;
    font-size: 1rem;
    line-height: 1.6;
    margin-bottom: 1rem;
}

#text-input:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.1);
}

.text-stats {
    display: flex;
    gap: 1rem;
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

/* Progress Section */
.progress-section {
    background: var(--card-bg);
    border-radius: var(--border-radius-lg);
    padding: 2rem;
    margin-bottom: 2rem;
}

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

.cancel-btn {
    background: var(--error-color);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

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

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--secondary-bg);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 1rem;
}

.progress-fill {
    height: 100%;
    background: var(--gradient-accent);
    width: 0%;
    transition: width 0.3s ease;
}

.progress-text {
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.progress-details {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Results Section */
.results-section {
    background: var(--card-bg);
    border-radius: var(--border-radius-lg);
    padding: 2rem;
    margin-bottom: 2rem;
}

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

.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1rem;
}

.result-item {
    background: var(--secondary-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.result-icon {
    font-size: 2rem;
    color: var(--success-color);
}

.result-info {
    flex: 1;
}

.result-info h4 {
    margin-bottom: 0.25rem;
    font-size: 0.9rem;
}

.result-info p {
    color: var(--text-muted);
    font-size: 0.8rem;
}

.download-result {
    background: var(--gradient-accent);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
}

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

/* Modals */
.modal {
    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: 1000;
    backdrop-filter: blur(5px);
}

.modal-content {
    background: var(--secondary-bg);
    border-radius: var(--border-radius-lg);
    max-width: 500px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: var(--shadow-hover);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
}

.close-btn {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.2rem;
    cursor: pointer;
    transition: var(--transition);
}

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

.modal-body {
    padding: 1.5rem;
}

.setting-group {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    padding: 1rem 0;
    border-bottom: 1px solid var(--border-color);
}

.setting-group:last-child {
    border-bottom: none;
}

.setting-group label {
    font-weight: 500;
}

.setting-group select,
.setting-group input[type="checkbox"] {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 0.5rem;
    border-radius: var(--border-radius);
}

.help-section {
    margin-bottom: 2rem;
}

.help-section h4 {
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.help-section ol {
    padding-left: 1.5rem;
    margin-bottom: 1rem;
}

.help-section li {
    margin-bottom: 0.5rem;
}

.format-list div {
    margin-bottom: 0.5rem;
    padding: 0.5rem;
    background: var(--card-bg);
    border-radius: var(--border-radius);
}

/* Responsive Design */
@media (max-width: 768px) {
    .main-content {
        padding: 1rem;
    }
    
    .conversion-grid {
        grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    }
    
    .features-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .category-tabs {
        gap: 0.25rem;
    }
    
    .category-tab {
        padding: 0.5rem 1rem;
        font-size: 0.9rem;
    }
    
    .conversion-options {
        flex-direction: column;
        align-items: stretch;
    }
    
    .option-group {
        justify-content: space-between;
    }
    
    .results-grid {
        grid-template-columns: 1fr;
    }
    
    .modal-content {
        width: 95%;
        margin: 1rem;
    }
}

@media (max-width: 480px) {
    .main-title {
        font-size: 2.5rem;
    }
    
    .subtitle {
        font-size: 1.2rem;
    }
    
    .conversion-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .conversion-btn {
        padding: 1rem;
        min-height: 100px;
    }
    
    .conversion-btn i {
        font-size: 1.5rem;
    }
    
    .conversion-btn .btn-title {
        font-size: 0.8rem;
    }
    
    .upload-section {
        padding: 1rem;
    }
    
    .upload-area {
        padding: 1rem;
    }
    
    .text-input-section {
        padding: 1rem;
    }
    
    #text-input {
        min-height: 150px;
    }
}

/* Animations */
@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.conversion-btn,
.file-item,
.result-item {
    animation: slideIn 0.3s ease;
}

.modal-content {
    animation: fadeInUp 0.3s ease;
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--secondary-bg);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-color);
}

/* Focus Styles */
button:focus,
input:focus,
select:focus,
textarea:focus {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

/* Print Styles */
@media print {
    .app-header,
    .category-tabs,
    .upload-section,
    .text-input-section,
    .progress-section,
    .modal {
        display: none !important;
    }
    
    .results-section {
        background: white;
        color: black;
        box-shadow: none;
    }
}