:root {
    --bg-color: #f8fafc; /* Very light slate/white */
    --card-bg: rgba(255, 255, 255, 0.8);
    --border-color: rgba(148, 163, 184, 0.2);
    --text-primary: #0f172a; /* Dark slate */
    --text-secondary: #64748b; /* Slate grey */
    --accent-color: #0ea5e9; /* Sky blue */
    --accent-hover: #0284c7;
    --active-gradient: linear-gradient(135deg, #0ea5e9 0%, #6366f1 100%);
    --blob-1: #e0e7ff; /* Very light indigo */
    --blob-2: #e0f2fe; /* Very light sky */
    --blob-3: #f3e8ff; /* Very light purple */
    --input-bg: #ffffff;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Outfit', sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    position: relative;
}

/* Background Animations */
.background-blobs {
    position: absolute;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
    top: 0;
    left: 0;
}

/* ... blobs ... */

dataviz-header {
    width: 100%;
    z-index: 1000;
}

/* Glass Card Container */
.container {
    flex: 1;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.glass-card {
    width: 100%;
    max-width: 500px;
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid #ffffff;
    border-radius: 24px;
    padding: 40px;
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.05), 0 0 0 1px rgba(255,255,255,0.5) inset;
    text-align: center;
}

header h1 {
    font-weight: 700;
    font-size: 2rem;
    margin-bottom: 8px;
    color: var(--text-primary);
    background: var(--active-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 32px;
}

/* Upload Section */
.upload-section {
    background: var(--input-bg);
    border: 2px dashed var(--border-color);
    border-radius: 16px;
    padding: 40px 20px;
    transition: all 0.3s ease;
    cursor: pointer;
    margin-bottom: 32px;
}

.upload-section:hover, .upload-section.drag-over {
    border-color: var(--accent-color);
    background: #f0f9ff;
    transform: scale(1.01);
}

.icon-container {
    color: #94a3b8;
    margin-bottom: 16px;
    transition: color 0.3s ease;
}

.upload-section:hover .icon-container {
    color: var(--accent-color);
}

.upload-section h3 {
    color: var(--text-primary);
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.upload-section p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Options */
.options-section {
    margin-bottom: 32px;
    text-align: left;
}

.option-label {
    display: block;
    color: var(--text-secondary);
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 12px;
}

.toggle-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

input[type="radio"] {
    display: none;
}

.toggle-btn {
    background: var(--input-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 16px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.02);
}

.toggle-btn:hover {
    border-color: #cbd5e1;
    background: #f8fafc;
}

input[type="radio"]:checked + .toggle-btn {
    border-color: var(--accent-color);
    background: #f0f9ff;
    box-shadow: 0 4px 12px -2px rgba(14, 165, 233, 0.15);
}

.toggle-btn .btn-title {
    display: block;
    font-weight: 600;
    font-size: 1rem;
    color: var(--text-primary);
    margin-bottom: 4px;
}

input[type="radio"]:checked + .toggle-btn .btn-title {
    color: var(--accent-color);
}

.toggle-btn .btn-desc {
    display: block;
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* Button */
.primary-btn {
    width: 100%;
    padding: 16px;
    border-radius: 12px;
    border: none;
    background: var(--active-gradient);
    color: white;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    position: relative;
    overflow: hidden;
    box-shadow: 0 10px 20px -5px rgba(99, 102, 241, 0.3);
}

.primary-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    background: #cbd5e1;
    box-shadow: none;
}

.primary-btn:not(:disabled):hover {
    transform: translateY(-2px);
    box-shadow: 0 15px 30px -5px rgba(99, 102, 241, 0.4);
}

.primary-btn:not(:disabled):active {
    transform: translateY(0);
}

/* Status Area */
.status-area {
    margin-top: 24px;
    text-align: left;
}

.status-area.hidden {
    display: none;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: #e2e8f0;
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 8px;
}

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

#status-text {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

/* Responsive */
@media (max-width: 480px) {
    .glass-card {
        padding: 24px;
    }
    
    .toggle-container {
        grid-template-columns: 1fr;
    }
}