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

:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --secondary-color: #8b5cf6;
    --success-color: #10b981;
    --error-color: #ef4444;
    --warning-color: #f59e0b;
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 2rem 1rem;
    color: var(--text-primary);
}

.container {
    max-width: 800px;
    margin: 0 auto;
}

header {
    text-align: center;
    margin-bottom: 2rem;
    color: white;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    text-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.subtitle {
    font-size: 1.1rem;
    opacity: 0.9;
}

.card {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow-lg);
}

.card h2 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Upload Area */
.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: var(--bg-color);
    position: relative;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.upload-area:hover,
.upload-area.dragover {
    border-color: var(--primary-color);
    background: #f0f9ff;
}

.upload-prompt svg {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.upload-prompt .highlight {
    color: var(--primary-color);
    font-weight: 600;
}

.upload-prompt small {
    display: block;
    margin-top: 0.5rem;
    color: var(--text-secondary);
}

#image-preview {
    max-width: 100%;
    max-height: 300px;
    border-radius: 8px;
    object-fit: contain;
}

.status-message {
    margin-top: 0.75rem;
    padding: 0.5rem;
    border-radius: 6px;
    font-size: 0.875rem;
    display: none;
}

.status-message.success {
    background: #d1fae5;
    color: #065f46;
    display: block;
}

.status-message.error {
    background: #fee2e2;
    color: #991b1b;
    display: block;
}

/* Form Elements */
.form-group {
    margin-bottom: 1.25rem;
}

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

.form-group small.help-text {
    display: block;
    margin-top: 0.25rem;
    color: var(--text-secondary);
    font-weight: normal;
}

textarea,
select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.3s ease;
}

textarea:focus,
select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

textarea {
    resize: vertical;
    min-height: 80px;
}

.char-counter {
    float: right;
    font-weight: normal;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

/* Slider Styles */
.slider-group {
    margin-bottom: 1.5rem;
}

.slider-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.slider-labels {
    display: flex;
    justify-content: space-between;
    font-weight: normal;
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-top: 0.25rem;
}

input[type="range"] {
    width: 100%;
    height: 8px;
    border-radius: 4px;
    background: var(--border-color);
    outline: none;
    -webkit-appearance: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    box-shadow: var(--shadow);
    transition: background 0.3s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
    background: var(--primary-hover);
}

input[type="range"]::-moz-range-thumb {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    border: none;
    box-shadow: var(--shadow);
}

.slider-hints {
    display: flex;
    justify-content: space-between;
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
}

/* Buttons */
.btn-primary,
.btn-secondary {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
    width: 100%;
    justify-content: center;
    padding: 1rem;
    font-size: 1.1rem;
}

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

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

.btn-secondary {
    background: var(--bg-color);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--border-color);
}

/* Output Section */
.output-container {
    background: var(--bg-color);
    border-radius: 8px;
    padding: 1rem;
}

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

.output-header h3 {
    font-size: 1rem;
    color: var(--text-primary);
}

#output-text {
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 1rem;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    line-height: 1.6;
    white-space: pre-wrap;
    word-wrap: break-word;
    max-height: 400px;
    overflow-y: auto;
}

.metadata {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.metadata span {
    display: inline-block;
    margin-right: 1rem;
    margin-bottom: 0.5rem;
}

/* Footer */
footer {
    text-align: center;
    color: white;
    margin-top: 2rem;
    opacity: 0.9;
}

footer a {
    color: white;
    text-decoration: underline;
}

.version {
    font-size: 0.875rem;
    margin-top: 0.5rem;
    opacity: 0.8;
}

/* Responsive */
@media (max-width: 640px) {
    body {
        padding: 1rem 0.5rem;
    }

    header h1 {
        font-size: 2rem;
    }

    .card {
        padding: 1rem;
    }

    .output-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }
}

/* Loading Animation */
@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255,255,255,.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

.btn-primary.loading {
    pointer-events: none;
    opacity: 0.8;
}