:root {
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(148, 163, 184, 0.1);
}

.work-area {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
}

.qr-builder-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
}

@media (max-width: 768px) {
    .qr-builder-grid {
        grid-template-columns: 1fr;
    }
}

.glass-panel {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(12px);
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
}

/* TABS */
.tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    padding-bottom: 15px;
}

.tab-btn {
    background: transparent;
    border: 1px solid transparent;
    color: #94a3b8;
    padding: 8px 16px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.2s;
}

.tab-btn:hover {
    color: white;
    background: rgba(255, 255, 255, 0.05);
}

.tab-btn.active {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.hidden {
    display: none;
}

/* Inputs */
.input-group {
    margin-bottom: 15px;
    text-align: left;
}

label {
    display: block;
    font-size: 0.85rem;
    color: #cbd5e1;
    margin-bottom: 5px;
    font-weight: 500;
}

input[type="text"],
input[type="number"],
select {
    width: 100%;
    background: #0f172a;
    border: 1px solid #334155;
    color: white;
    padding: 12px;
    border-radius: 8px;
    outline: none;
}

input[type="text"]:focus {
    border-color: #8b5cf6;
}

.divider {
    height: 1px;
    background: rgba(255, 255, 255, 0.1);
    margin: 20px 0;
}

/* Design */
.design-grid {
    display: flex;
    gap: 20px;
}

input[type="color"] {
    width: 100%;
    height: 40px;
    border: none;
    background: transparent;
    cursor: pointer;
}

/* Preview */
.preview-panel {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.02);
    /* Lighter for contrast */
}

#qr-canvas {
    background: white;
    /* Ensure white bg for QR if transparent selected */
    padding: 20px;
    border-radius: 12px;
    margin-bottom: 30px;
}

/* Helpers */
.btn-primary {
    background: var(--primary-gradient);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
}

.btn-outline {
    border: 1px solid #475569;
    background: transparent;
    color: #ccc;
    padding: 8px 16px;
    border-radius: 8px;
}

h3 {
    font-size: 1.1rem;
    color: white;
    margin-bottom: 15px;
}