static/style.css

:root {
    /* Color Palette - Slate/Zinc Dark Mode */
    --bg-base: #18181b;
    --bg-card: #27272a;
    --bg-input: #3f3f46;
    --bg-input-hover: #52525b;
    
    --border-color: #3f3f46;
    --border-focus: #71717a;
    
    --text-primary: #f4f4f5;
    --text-secondary: #a1a1aa;
    
    --accent-color: #e4e4e7;
    --accent-hover: #ffffff;
    
    --error-bg: #450a0a;
    --error-text: #fca5a5;
    --error-border: #991b1b;
    
    /* Spacing & Layout */
    --radius: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
}

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

body {
    background-color: var(--bg-base);
    color: var(--text-primary);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji";
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
}

.dashboard-container {
    width: 100%;
    max-width: 480px;
    padding: var(--spacing-lg);
}

.card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: var(--spacing-xl);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.5), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
}

.card-header {
    margin-bottom: var(--spacing-xl);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: var(--spacing-md);
    display: flex;
    flex-direction: column;
    align-items: center;
}

.card-header h2 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    letter-spacing: -0.025em;
}

.card-header p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.upload-section {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.file-input-wrapper {
    position: relative;
    width: 100%;
}

.file-label {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl);
    background-color: var(--bg-input);
    border: 2px dashed var(--border-color);
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 0.875rem;
    color: var(--text-secondary);
    transition: all 0.2s ease;
    gap: var(--spacing-sm);
}

.file-label.dragover {
    background-color: var(--bg-input-hover);
    border-color: var(--accent-color);
    color: var(--text-primary);
}

.upload-icon {
    color: var(--text-secondary);
    transition: color 0.2s ease;
}

.file-label:hover {
    background-color: var(--bg-input-hover);
    border-color: var(--border-focus);
    color: var(--text-primary);
}

.file-label:hover .upload-icon {
    color: var(--text-primary);
}

input[type="file"] {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

#image-preview-container {
    position: relative;
    width: 100%;
    border-radius: var(--radius);
    overflow: hidden;
    background-color: #000;
    border: 1px solid var(--border-color);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 200px;
    max-height: 300px;
}

#image-preview {
    max-width: 100%;
    max-height: 300px;
    object-fit: contain;
    display: block;
}

.icon-button {
    position: absolute;
    top: var(--spacing-sm);
    right: var(--spacing-sm);
    background-color: rgba(24, 24, 27, 0.8);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
    padding: 0;
}

.icon-button:hover {
    background-color: var(--error-bg);
    color: var(--error-text);
    border-color: var(--error-border);
}

.primary-button {
    background-color: var(--accent-color);
    color: var(--bg-base);
    border: none;
    border-radius: var(--radius);
    padding: 12px var(--spacing-md);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s ease;
    width: 100%;
}

.primary-button:hover:not(:disabled) {
    background-color: var(--accent-hover);
}

.primary-button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* State Panels */
.state-panel {
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--border-color);
}

.hidden {
    display: none !important;
}

/* Loading State */
#loading-state {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.spinner {
    width: 16px;
    height: 16px;
    border: 2px solid var(--border-color);
    border-top-color: var(--accent-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* Results Panel */
.results h3 {
    font-size: 1rem;
    font-weight: 500;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

.result-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-md);
    display: flex;
    flex-direction: column;
}

.result-item {
    background-color: var(--bg-input);
    padding: var(--spacing-md);
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.result-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
}

.result-value {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

/* Error Panel */
.error {
    background-color: var(--error-bg);
    border: 1px solid var(--error-border);
    border-radius: var(--radius);
    padding: var(--spacing-md);
    color: var(--error-text);
    font-size: 0.875rem;
    border-top: 1px solid var(--error-border); /* override default state panel border */
}