.card {
    background-color: var(--card-bg, var(--surface-color));
    border-radius: 12px;
    box-shadow: var(--shadow);
    padding: 2.5rem;
    margin: 0 auto;
    transition: all 0.3s ease;
    text-align: center;
    max-width: 900px;
}

/* Tabs Styling */
.tabs {
    display: flex;
    border-bottom: 2px solid var(--border-color);
    margin-bottom: 2rem;
    justify-content: center;
}

.tab {
    padding: 1rem 1.5rem;
    cursor: pointer;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--muted-text);
    background-color: transparent;
    border: none;
    border-bottom: 3px solid transparent;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.tab:hover {
    background-color: var(--surface-subtle);
    color: var(--text-color);
}

.tab.active {
    color: var(--primary);
    border-bottom: 3px solid var(--primary);
}

.tab-content {
    display: none;
    animation: fadeIn 0.5s;
    text-align: center;
    width: 100%;
}

.tab-content.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Form Groups and Inputs */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-bottom: 1rem;
    text-align: left;
}

.form-group label {
    font-weight: 600;
    color: var(--text-color);
}

.form-group input[type="text"],
.form-group input[type="url"],
.form-group input[type="tel"],
.form-group input[type="email"],
.form-group input[type="number"],
.form-group input[type="range"],
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    box-sizing: border-box;
    transition: border-color 0.3s, box-shadow 0.3s;
    font-size: 1rem;
}

.form-group input[type="color"] {
    height: 48px;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    border-color: var(--primary);
    outline: none;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.spaced-form-grid {
    margin-top: 1.5rem;
}

/* Error Styling */
.error {
    color: #d9534f;
    background-color: #f2dede;
    border: 1px solid #ebccd1;
    border-radius: 4px;
    padding: 1rem;
    margin-top: 1.5rem;
    display: none;
}

.error.show {
    display: block;
}

/* File Upload Area */
.file-upload-area {
    border: 2px dashed var(--primary-color, #0056b3);
    border-radius: 8px;
    padding: 2.5rem 1.5rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background-color: rgba(37, 99, 235, 0.03);
    position: relative;
}

.file-upload-area:hover, .file-upload-area.drag-over {
    background-color: rgba(37, 99, 235, 0.07);
    border-color: var(--primary);
}

.file-upload-area i {
    font-size: 3rem;
    color: var(--primary-color, #0056b3);
    margin-bottom: 1rem;
}

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

.file-upload-area p {
    color: var(--muted-text);
    font-size: 0.9rem;
}

.file-upload-area input[type="file"] {
    position: absolute;
    left: 0;
    top: 0;
    opacity: 0;
    width: 100%;
    height: 100%;
    cursor: pointer;
}

/* Options Sections (Color, Logo, etc.) */
.options-container {
    margin-top: 2rem;
    border: 1px solid var(--border-color, #e0e0e0);
    border-radius: 8px;
    overflow: hidden;
    background-color: var(--card-bg, #fff);
    width: 100%;
    text-align: left;
}

.options-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    background-color: var(--bg-secondary, var(--surface-subtle));
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.options-header:hover {
    background-color: var(--bg-hover, var(--hover-color));
}

.options-title {
    font-weight: 600;
    font-size: 1rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.options-header .toggle-icon {
    transition: transform 0.3s ease;
}

.options-container.open .options-header .toggle-icon {
    transform: rotate(180deg);
}

.options-content {
    display: none;
    padding: 1.5rem;
    border-top: 1px solid var(--border-color, #e0e0e0);
    animation: fadeIn 0.5s;
}

.options-container.open .options-content {
    display: block;
}

/* Toggle Switch */
.toggle-switch {
    position: relative;
    display: inline-block;
    width: 50px;
    height: 28px;
}

.toggle-switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0; left: 0; right: 0; bottom: 0;
    background-color: #ccc;
    transition: .4s;
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 20px; width: 20px;
    left: 4px; bottom: 4px;
    background-color: var(--surface-color);
    transition: .4s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: var(--primary);
}

input:checked + .slider:before {
    transform: translateX(22px);
}

/* Color Input Swatch */
.color-input-wrapper {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
}

.form-group input[type="color"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 48px;
    background-color: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
}

.form-group input[type="color"]::-webkit-color-swatch {
    border-radius: 4px;
    border: 1px solid var(--border-color);
}

/* Buttons */
.btn-group {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
    margin-top: 2rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.8rem 1.8rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 6px;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
    background-color: var(--primary);
    color: #fff;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    background-color: #1d4ed8;
}

.btn-secondary {
    background-color: #475569;
}

.btn-secondary:hover {
    background-color: #334155;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

/* QR Result Area Styling */
.qr-result-container {
    margin-top: 2.5rem;
    padding: 2.5rem;
    background-color: var(--surface-subtle);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    min-height: 350px;
    display: none;
    justify-content: center;
    align-items: center;
    position: relative;
    overflow: hidden;
}

#qr-canvas {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
}

#qr-canvas canvas,
#qr-canvas img {
    max-width: 100%;
    height: auto;
    display: block;
    box-shadow: 0 8px 30px rgba(0,0,0,0.08);
}

/* Image Overlay Styling */
.overlay-preview-container {
    margin-top: 1rem;
    position: relative;
    border: 1px dashed var(--border-color, #ccc);
    overflow: hidden;
    max-width: 100%;
    border-radius: 8px;
    background-color: var(--surface-subtle);
    display: flex;
    justify-content: center;
    align-items: center;
}

#overlay-preview-canvas, #bulk-overlay-preview-canvas {
    display: block;
    max-width: 100%;
    height: auto;
    margin: 0 auto;
    cursor: move;
    background-color: var(--surface-color);
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

/* Scanner */
.scanner-container {
    display: flex;
    justify-content: center;
    align-items: center;
    margin: 2rem auto;
    max-width: 100%;
    overflow: hidden;
    background: #000;
    border-radius: 8px;
}

.scanner-container video {
    display: block;
    margin: 0 auto;
    max-width: 100%;
    height: auto;
}

.scan-result {
    margin-top: 2rem;
    padding: 1.5rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--surface-subtle);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-color);
    text-align: center;
    word-break: break-all;
}

/* Range and Number Sync */
.range-with-number {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.range-with-number input[type='range'] {
    flex: 1;
}

.range-with-number input[type='number'] {
    width: 65px;
    padding: 0.5rem;
    border-radius: 4px;
    border: 1px solid var(--border-color, #ccc);
    text-align: center;
}

/* Loading Spinner */
.loading {
    display: none;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    font-size: 1.1rem;
    color: var(--muted-text);
    margin-top: 2rem;
}

.spinner {
    width: 24px;
    height: 24px;
    border: 3px solid var(--surface-strong);
    border-top: 3px solid var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

.success {
    display: none;
    text-align: center;
    padding: 1rem;
    background-color: #e6faed;
    color: #28a745;
    border: 1px solid #a6e0b9;
    border-radius: 4px;
    margin-top: 2rem;
}

/* Mobile Adjustments */
@media (max-width: 768px) {
    .form-grid { grid-template-columns: 1fr; }
    .btn-group { flex-direction: column; align-items: stretch; }
    .btn { justify-content: center; }
}