/* Variables CSS pour les thèmes */
:root {
    --primary-color: #0078d4;
    --secondary-color: #106ebe;
    --accent-color: #00bcf2;
    --text-primary: #323130;
    --text-secondary: #605e5c;
    --background-primary: #ffffff;
    --background-secondary: #f3f2f1;
    --background-tertiary: #faf9f8;
    --border-color: #edebe9;
    --shadow-light: 0 1.6px 3.6px 0 rgba(0, 0, 0, 0.132), 0 0.3px 0.9px 0 rgba(0, 0, 0, 0.108);
    --shadow-medium: 0 6.4px 14.4px 0 rgba(0, 0, 0, 0.132), 0 1.2px 3.6px 0 rgba(0, 0, 0, 0.108);
    --shadow-heavy: 0 25.6px 57.6px 0 rgba(0, 0, 0, 0.22), 0 4.8px 14.4px 0 rgba(0, 0, 0, 0.18);
    --border-radius: 8px;
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

body {
    font-family: 'Segoe UI', 'Segoe UI Web', 'Segoe UI Symbol', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--background-primary);
    transition: var(--transition);
    overflow-x: hidden;
}

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

/* Loading Screen */
.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--background-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 10000;
    transition: opacity 0.5s, visibility 0.5s;
}

.loading-screen.hidden {
    opacity: 0;
    visibility: hidden;
}

.loader {
    text-align: center;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

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

/* Popup Styles */
.popup-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    opacity: 1;
    transition: var(--transition);
    backdrop-filter: blur(10px);
}

.popup-overlay.hidden {
    opacity: 0;
    visibility: hidden;
}

.popup-content {
    background: var(--background-primary);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-heavy);
    max-width: 500px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    animation: popupSlideIn 0.3s ease-out;
}

@keyframes popupSlideIn {
    from {
        transform: scale(0.9) translateY(-20px);
        opacity: 0;
    }
    to {
        transform: scale(1) translateY(0);
        opacity: 1;
    }
}

.popup-header {
    padding: 24px 24px 0;
    text-align: center;
    position: relative;
}

.popup-logo {
    font-size: 48px;
    margin-bottom: 16px;
}

.popup-header h2 {
    font-size: 24px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.close-btn {
    position: absolute;
    top: 16px;
    right: 16px;
    background: none;
    border: none;
    font-size: 24px;
    color: var(--text-secondary);
    cursor: pointer;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

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

.popup-body {
    padding: 16px 24px;
}

.popup-body p {
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.features-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin: 20px 0;
}

.feature {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px;
    background: var(--background-secondary);
    border-radius: var(--border-radius);
}

.feature-icon {
    font-size: 20px;
}

.privacy-note {
    background: var(--background-tertiary);
    padding: 12px;
    border-radius: var(--border-radius);
    font-size: 14px;
    color: var(--text-secondary);
    border-left: 4px solid var(--primary-color);
}

.popup-footer {
    padding: 0 24px 24px;
    text-align: center;
}

/* Header Styles */
.header {
    background: var(--background-primary);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-light);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 0;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 16px;
}

.logo {
    font-size: 32px;
    animation: rotate 2s linear infinite;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.brand-name {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 4px;
}

.tagline {
    font-size: 14px;
    color: var(--text-secondary);
}

.theme-selector {
    display: flex;
    align-items: center;
    gap: 12px;
}

.theme-label {
    font-size: 14px;
    color: var(--text-secondary);
    font-weight: 500;
}

.theme-dropdown {
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background: var(--background-primary);
    color: var(--text-primary);
    font-size: 14px;
    cursor: pointer;
    transition: var(--transition);
    min-width: 120px;
}

.theme-dropdown:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Main Content */
.main-content {
    padding: 40px 0;
    min-height: calc(100vh - 200px);
}

.conversion-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 32px;
    margin-bottom: 60px;
}

.conversion-card {
    background: var(--background-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-medium);
    transition: var(--transition);
    overflow: hidden;
}

.conversion-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-heavy);
}

.card-header {
    padding: 24px;
    text-align: center;
    background: var(--background-tertiary);
    border-bottom: 1px solid var(--border-color);
}

.card-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.card-header h2 {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.card-header p {
    color: var(--text-secondary);
    font-size: 14px;
}

.card-body {
    padding: 24px;
}

/* File Input Styles */
.file-input-wrapper {
    position: relative;
    margin-bottom: 16px;
}

.file-input {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
    z-index: 2;
}

.file-label {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 20px;
    border: 2px dashed var(--border-color);
    border-radius: var(--border-radius);
    background: var(--background-secondary);
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.file-label:hover {
    border-color: var(--primary-color);
    background: var(--background-tertiary);
}

.file-input:focus + .file-label {
    border-color: var(--primary-color);
    background: var(--background-tertiary);
}

.file-icon {
    font-size: 24px;
}

.file-text {
    font-weight: 500;
    color: var(--text-primary);
}

.clear-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    width: 24px;
    height: 24px;
    background: #d13438;
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    font-size: 16px;
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 3;
    transition: var(--transition);
}

.clear-btn:hover {
    background: #a4262c;
    transform: scale(1.1);
}

.file-input-wrapper.has-file .clear-btn {
    display: flex;
}

.file-input-wrapper.has-file .file-label {
    border-color: var(--primary-color);
    background: var(--background-tertiary);
}

/* File Info */
.file-info {
    margin-bottom: 16px;
    padding: 12px;
    background: var(--background-secondary);
    border-radius: var(--border-radius);
    font-size: 14px;
    color: var(--text-secondary);
    display: none;
}

.file-info.visible {
    display: block;
}

/* Buttons */
.btn-primary, .btn-convert {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: var(--border-radius);
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 8px;
    justify-content: center;
    min-width: 160px;
}

.btn-primary:hover, .btn-convert:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

.btn-convert:disabled {
    background: var(--border-color);
    color: var(--text-secondary);
    cursor: not-allowed;
    transform: none;
}

.btn-icon {
    font-size: 18px;
}

.btn-convert.loading .btn-icon {
    animation: spin 1s linear infinite;
}

/* Status Messages */
.status-message {
    margin-top: 16px;
    padding: 12px;
    border-radius: var(--border-radius);
    font-size: 14px;
    font-weight: 500;
    text-align: center;
    display: none;
}

.status-message.success {
    background: #dff6dd;
    color: #107c10;
    border: 1px solid #c8e6c9;
    display: block;
}

.status-message.error {
    background: #fde7e9;
    color: #d13438;
    border: 1px solid #f1aeb5;
    display: block;
}

.status-message.info {
    background: #deecf9;
    color: #0078d4;
    border: 1px solid #c7e0f4;
    display: block;
}

/* Features Section */
.features-section {
    text-align: center;
    padding: 60px 0;
    background: var(--background-tertiary);
    border-radius: var(--border-radius);
    margin: 40px 0;
}

.features-section h2 {
    font-size: 28px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 40px;
}

.features-section .features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 32px;
    margin-top: 40px;
}

.feature-card {
    text-align: center;
    padding: 24px;
}

.feature-card .feature-icon {
    font-size: 48px;
    margin-bottom: 16px;
    display: block;
}

.feature-card h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
}

/* Footer */
.footer {
    background: var(--background-secondary);
    border-top: 1px solid var(--border-color);
    padding: 32px 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-info {
    display: flex;
    align-items: center;
    gap: 16px;
}

.footer-info p {
    color: var(--text-secondary);
    font-size: 14px;
}

.kofi-link {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 20px;
    background: #ff5f5f;
    color: white;
    text-decoration: none;
    border-radius: 25px;
}
/* Variables CSS pour les thèmes */
:root {
    --primary-color: #0078d4;
    --secondary-color: #106ebe;
    --accent-color: #00bcf2;
    --text-primary: #323130;
    --text-secondary: #605e5c;
    --background-primary: #ffffff;
    --background-secondary: #f3f2f1;
    --background-tertiary: #faf9f8;
    --border-color: #edebe9;
    --shadow-light: 0 1.6px 3.6px 0 rgba(0, 0, 0, 0.132), 0 0.3px 0.9px 0 rgba(0, 0, 0, 0.108);
    --shadow-medium: 0 6.4px 14.4px 0 rgba(0, 0, 0, 0.132), 0 1.2px 3.6px 0 rgba(0, 0, 0, 0.108);
    --shadow-heavy: 0 25.6px 57.6px 0 rgba(0, 0, 0, 0.22), 0 4.8px 14.4px 0 rgba(0, 0, 0, 0.18);
    --border-radius: 8px;
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

body {
    font-family: 'Segoe UI', 'Segoe UI Web', 'Segoe UI Symbol', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--background-primary);
    transition: var(--transition);
    overflow-x: hidden;
}

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

/* Loading Screen */
.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--background-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 10000;
    transition: opacity 0.5s, visibility 0.5s;
}

.loading-screen.hidden {
    opacity: 0;
    visibility: hidden;
}

.loader {
    text-align: center;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

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

/* Popup Styles */
.popup-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    opacity: 1;
    transition: var(--transition);
    backdrop-filter: blur(10px);
}

.popup-overlay.hidden {
    opacity: 0;
    visibility: hidden;
}

.popup-content {
    background: var(--background-primary);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-heavy);
    max-width: 500px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    animation: popupSlideIn 0.3s ease-out;
}

@keyframes popupSlideIn {
    from {
        transform: scale(0.9) translateY(-20px);
        opacity: 0;
    }
    to {
        transform: scale(1) translateY(0);
        opacity: 1;
    }
}

.popup-header {
    padding: 24px 24px 0;
    text-align: center;
    position: relative;
}

.popup-logo {
    font-size: 48px;
    margin-bottom: 16px;
}

.popup-header h2 {
    font-size: 24px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.close-btn {
    position: absolute;
    top: 16px;
    right: 16px;
    background: none;
    border: none;
    font-size: 24px;
    color: var(--text-secondary);
    cursor: pointer;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

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

.popup-body {
    padding: 16px 24px;
}

.popup-body p {
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.features-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin: 20px 0;
}

.feature {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px;
    background: var(--background-secondary);
    border-radius: var(--border-radius);
}

.feature-icon {
    font-size: 20px;
}

.privacy-note {
    background: var(--background-tertiary);
    padding: 12px;
    border-radius: var(--border-radius);
    font-size: 14px;
    color: var(--text-secondary);
    border-left: 4px solid var(--primary-color);
}

.popup-footer {
    padding: 0 24px 24px;
    text-align: center;
}

/* Header Styles */
.header {
    background: var(--background-primary);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-light);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 0;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 16px;
}

.logo {
    font-size: 32px;
    animation: rotate 2s linear infinite;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.brand-name {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 4px;
}

.tagline {
    font-size: 14px;
    color: var(--text-secondary);
}

.theme-selector {
    display: flex;
    align-items: center;
    gap: 12px;
}

.theme-label {
    font-size: 14px;
    color: var(--text-secondary);
    font-weight: 500;
}

.theme-dropdown {
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background: var(--background-primary);
    color: var(--text-primary);
    font-size: 14px;
    cursor: pointer;
    transition: var(--transition);
    min-width: 120px;
}

.theme-dropdown:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Main Content */
.main-content {
    padding: 40px 0;
    min-height: calc(100vh - 200px);
}

.conversion-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 32px;
    margin-bottom: 60px;
}

.conversion-card {
    background: var(--background-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-medium);
    transition: var(--transition);
    overflow: hidden;
}

.conversion-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-heavy);
}

.card-header {
    padding: 24px;
    text-align: center;
    background: var(--background-tertiary);
    border-bottom: 1px solid var(--border-color);
}

.card-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.card-header h2 {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.card-header p {
    color: var(--text-secondary);
    font-size: 14px;
}

.card-body {
    padding: 24px;
}

/* File Input Styles */
.file-input-wrapper {
    position: relative;
    margin-bottom: 16px;
}

.file-input {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
    z-index: 2;
}

.file-label {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 20px;
    border: 2px dashed var(--border-color);
    border-radius: var(--border-radius);
    background: var(--background-secondary);
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.file-label:hover {
    border-color: var(--primary-color);
    background: var(--background-tertiary);
}

.file-input:focus + .file-label {
    border-color: var(--primary-color);
    background: var(--background-tertiary);
}

.file-icon {
    font-size: 24px;
}

.file-text {
    font-weight: 500;
    color: var(--text-primary);
}

.clear-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    width: 24px;
    height: 24px;
    background: #d13438;
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    font-size: 16px;
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 3;
    transition: var(--transition);
}

.clear-btn:hover {
    background: #a4262c;
    transform: scale(1.1);
}

.file-input-wrapper.has-file .clear-btn {
    display: flex;
}

.file-input-wrapper.has-file .file-label {
    border-color: var(--primary-color);
    background: var(--background-tertiary);
}

/* File Info */
.file-info {
    margin-bottom: 16px;
    padding: 12px;
    background: var(--background-secondary);
    border-radius: var(--border-radius);
    font-size: 14px;
    color: var(--text-secondary);
    display: none;
}

.file-info.visible {
    display: block;
}

/* Buttons */
.btn-primary, .btn-convert {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: var(--border-radius);
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 8px;
    justify-content: center;
    min-width: 160px;
}

.btn-primary:hover, .btn-convert:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

.btn-convert:disabled {
    background: var(--border-color);
    color: var(--text-secondary);
    cursor: not-allowed;
    transform: none;
}

.btn-icon {
    font-size: 18px;
}

.btn-convert.loading .btn-icon {
    animation: spin 1s linear infinite;
}

/* Status Messages */
.status-message {
    margin-top: 16px;
    padding: 12px;
    border-radius: var(--border-radius);
    font-size: 14px;
    font-weight: 500;
    text-align: center;
    display: none;
}

.status-message.success {
    background: #dff6dd;
    color: #107c10;
    border: 1px solid #c8e6c9;
    display: block;
}

.status-message.error {
    background: #fde7e9;
    color: #d13438;
    border: 1px solid #f1aeb5;
    display: block;
}

.status-message.info {
    background: #deecf9;
    color: #0078d4;
    border: 1px solid #c7e0f4;
    display: block;
}

/* Features Section */
.features-section {
    text-align: center;
    padding: 60px 0;
    background: var(--background-tertiary);
    border-radius: var(--border-radius);
    margin: 40px 0;
}

.features-section h2 {
    font-size: 28px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 40px;
}

.features-section .features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 32px;
    margin-top: 40px;
}

.feature-card {
    text-align: center;
    padding: 24px;
}

.feature-card .feature-icon {
    font-size: 48px;
    margin-bottom: 16px;
    display: block;
}

.feature-card h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
}

/* Footer */
.footer {
    background: var(--background-secondary);
    border-top: 1px solid var(--border-color);
    padding: 32px 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-info {
    display: flex;
    align-items: center;
    gap: 16px;
}

.footer-info p {
    color: var(--text-secondary);
    font-size: 14px;
}

.kofi-link {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 20px;
    background: #ff5f5f;
    color: white;
    text-decoration: none;
    border-radius: 25px;
    font-weight: 500;
    font-size: 14px;
    transition: var(--transition);
}

.kofi-link:hover {
    background: #e85555;
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

.kofi-logo {
    width: 20px;
    height: 20px;
}

/* Progress Modal */
.progress-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 10000;
    backdrop-filter: blur(5px);
}

.progress-modal.visible {
    display: flex;
}

.progress-content {
    background: var(--background-primary);
    padding: 32px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-heavy);
    text-align: center;
    min-width: 300px;
}

.progress-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 20px;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--background-secondary);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 16px;
}

.progress-fill {
    height: 100%;
    background: var(--primary-color);
    border-radius: 4px;
    transition: width 0.3s ease;
    width: 0%;
}

#progress-text {
    color: var(--text-secondary);
    font-size: 14px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
    
    .header-content {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
    
    .conversion-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    
    .features-section .features-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
    
    .popup-content {
        width: 95%;
        margin: 20px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
        gap: 12px;
    }
    
    .brand-name {
        font-size: 20px;
    }
    
    .tagline {
        font-size: 12px;
    }
}

@media (max-width: 480px) {
    .card-header, .card-body {
        padding: 16px;
    }
    
    .main-content {
        padding: 20px 0;
    }
    
    .features-section {
        padding: 40px 0;
    }
    
    .file-label {
        padding: 12px 16px;
        font-size: 14px;
    }
    
    .btn-primary, .btn-convert {
        padding: 10px 20px;
        font-size: 14px;
        min-width: 140px;
    }
}

/* Theme Variations */

/* Dark Theme (Default) */
.theme-dark {
    --primary-color: #0078d4;
    --secondary-color: #106ebe;
    --accent-color: #00bcf2;
    --text-primary: #ffffff;
    --text-secondary: #c8c6c4;
    --background-primary: #1f1f1f;
    --background-secondary: #2d2d30;
    --background-tertiary: #252526;
    --border-color: #3c3c3c;
    --shadow-light: 0 1.6px 3.6px 0 rgba(0, 0, 0, 0.3);
    --shadow-medium: 0 6.4px 14.4px 0 rgba(0, 0, 0, 0.4);
    --shadow-heavy: 0 25.6px 57.6px 0 rgba(0, 0, 0, 0.5);
}

/* Light Theme */
.theme-light {
    --primary-color: #0078d4;
    --secondary-color: #106ebe;
    --accent-color: #00bcf2;
    --text-primary: #323130;
    --text-secondary: #605e5c;
    --background-primary: #ffffff;
    --background-secondary: #f3f2f1;
    --background-tertiary: #faf9f8;
    --border-color: #edebe9;
    --shadow-light: 0 1.6px 3.6px 0 rgba(0, 0, 0, 0.132);
    --shadow-medium: 0 6.4px 14.4px 0 rgba(0, 0, 0, 0.132);
    --shadow-heavy: 0 25.6px 57.6px 0 rgba(0, 0, 0, 0.22);
}

/* Neon Theme */
.theme-neon {
    --primary-color: #ff00ff;
    --secondary-color: #cc00cc;
    --accent-color: #00ffff;
    --text-primary: #00ffff;
    --text-secondary: #ff00ff;
    --background-primary: #000000;
    --background-secondary: #111111;
    --background-tertiary: #0a0a0a;
    --border-color: #ff00ff;
    --shadow-light: 0 0 10px rgba(255, 0, 255, 0.3);
    --shadow-medium: 0 0 20px rgba(255, 0, 255, 0.4);
    --shadow-heavy: 0 0 30px rgba(255, 0, 255, 0.6);
}

.theme-neon .conversion-card {
    border: 2px solid var(--border-color);
    box-shadow: 0 0 20px rgba(255, 0, 255, 0.3);
}

.theme-neon .conversion-card:hover {
    box-shadow: 0 0 30px rgba(255, 0, 255, 0.6);
}

/* Hacker Theme */
.theme-hacker {
    --primary-color: #00ff00;
    --secondary-color: #00cc00;
    --accent-color: #00ff41;
    --text-primary: #00ff00;
    --text-secondary: #00cc00;
    --background-primary: #0a0a0a;
    --background-secondary: #1a1a1a;
    --background-tertiary: #111111;
    --border-color: #00ff00;
    --shadow-light: 0 0 10px rgba(0, 255, 0, 0.2);
    --shadow-medium: 0 0 15px rgba(0, 255, 0, 0.3);
    --shadow-heavy: 0 0 25px rgba(0, 255, 0, 0.4);
}

.theme-hacker * {
    font-family: 'Courier New', monospace !important;
}

.theme-hacker .conversion-card {
    border: 1px solid var(--border-color);
    background: var(--background-secondary);
}

/* Vintage Theme */
.theme-vintage {
    --primary-color: #8b4513;
    --secondary-color: #a0522d;
    --accent-color: #daa520;
    --text-primary: #2f1b14;
    --text-secondary: #5d4037;
    --background-primary: #fdf6e3;
    --background-secondary: #f4f1de;
    --background-tertiary: #e9dc9f;
    --border-color: #d4b896;
    --shadow-light: 0 2px 4px rgba(139, 69, 19, 0.2);
    --shadow-medium: 0 4px 8px rgba(139, 69, 19, 0.3);
    --shadow-heavy: 0 8px 16px rgba(139, 69, 19, 0.4);
}

.theme-vintage * {
    font-family: 'Georgia', serif !important;
}

/* Monochrome Theme */
.theme-monochrome {
    --primary-color: #000000;
    --secondary-color: #333333;
    --accent-color: #666666;
    --text-primary: #000000;
    --text-secondary: #666666;
    --background-primary: #ffffff;
    --background-secondary: #f5f5f5;
    --background-tertiary: #eeeeee;
    --border-color: #cccccc;
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.2);
    --shadow-medium: 0 2px 6px rgba(0, 0, 0, 0.3);
    --shadow-heavy: 0 4px 12px rgba(0, 0, 0, 0.4);
}

/* Royal Theme */
.theme-royal {
    --primary-color: #ffd700;
    --secondary-color: #ffb347;
    --accent-color: #ffa500;
    --text-primary: #ffd700;
    --text-secondary: #ffffff;
    --background-primary: #191970;
    --background-secondary: #1e1e3f;
    --background-tertiary: #252550;
    --border-color: #ffd700;
    --shadow-light: 0 2px 4px rgba(255, 215, 0, 0.3);
    --shadow-medium: 0 4px 8px rgba(255, 215, 0, 0.4);
    --shadow-heavy: 0 8px 16px rgba(255, 215, 0, 0.5);
}

.theme-royal .conversion-card {
    border: 2px solid var(--border-color);
}

/* Glassmorphism Theme */
.theme-glass {
    --primary-color: #00aaff;
    --secondary-color: #0088cc;
    --accent-color: #00ccff;
    --text-primary: #ffffff;
    --text-secondary: #cccccc;
    --background-primary: rgba(255, 255, 255, 0.1);
    --background-secondary: rgba(255, 255, 255, 0.2);
    --background-tertiary: rgba(255, 255, 255, 0.15);
    --border-color: rgba(255, 255, 255, 0.3);
    --shadow-light: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 8px 25px rgba(0, 0, 0, 0.15);
    --shadow-heavy: 0 15px 35px rgba(0, 0, 0, 0.2);
}

.theme-glass {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.theme-glass * {
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.theme-glass .conversion-card,
.theme-glass .popup-content,
.theme-glass .header,
.theme-glass .footer {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(15px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.theme-glass .file-label {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 2px dashed rgba(255, 255, 255, 0.3);
}

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

.conversion-card {
    animation: fadeInUp 0.6s ease-out forwards;
}

.conversion-card:nth-child(2) {
    animation-delay: 0.2s;
}

.conversion-card:nth-child(3) {
    animation-delay: 0.4s;
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    .logo {
        animation: none !important;
    }
}

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

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000000;
    }
    
    .theme-light {
        --border-color: #000000;
    }
}