:root {
    --bg-color: #f0f2f5;
    --card-bg: #ffffff;
    --text: #1f2937;
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --border: #e5e7eb;
}

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

body {
    font-family: 'Poppins', sans-serif;
    background-color: var(--bg-color);
    color: var(--text);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    padding: 2rem;
}

.container {
    width: 100%;
    max-width: 900px;
}

header {
    text-align: center;
    margin-bottom: 3rem;
}

h1 {
    font-size: 2.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.highlight {
    color: var(--primary);
}

.subtitle {
    color: #6b7280;
}

.generator-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

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

.card {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

/* Tabs */
.tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 2rem;
    background: #f3f4f6;
    padding: 0.25rem;
    border-radius: 0.5rem;
}

.tab-btn {
    flex: 1;
    padding: 0.5rem;
    border: none;
    background: transparent;
    border-radius: 0.25rem;
    cursor: pointer;
    font-weight: 600;
    color: #6b7280;
    transition: all 0.2s;
}

.tab-btn.active {
    background: white;
    color: var(--primary);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

/* Forms */
.form-group {
    display: none;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
}

.form-group.active {
    display: flex;
}

label {
    font-size: 0.9rem;
    font-weight: 600;
    color: #374151;
}

input,
textarea,
select {
    padding: 0.75rem;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    font-family: inherit;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
}

input:focus,
textarea:focus,
select:focus {
    border-color: var(--primary);
}

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

/* Customization */
.customization h3 {
    font-size: 1rem;
    margin-bottom: 1rem;
}

.color-pickers {
    display: flex;
    gap: 2rem;
}

.picker {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

input[type="color"] {
    height: 40px;
    width: 60px;
    padding: 0;
    border: none;
    cursor: pointer;
}

/* Preview */
.preview-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2rem;
    background: #f9fafb;
}

#qr-canvas-container {
    background: white;
    padding: 1rem;
    border-radius: 0.5rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
}

.primary-btn {
    background: var(--primary);
    color: white;
    border: none;
    padding: 0.75rem 2rem;
    border-radius: 0.5rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s;
}

.primary-btn:hover {
    background: var(--primary-hover);
}

.logo-picker {
    margin-top: 1rem;
    width: 100%;
}

.logo-picker input[type="file"] {
    border: 1px solid var(--border);
    padding: 0.5rem;
    width: 100%;
    background: white;
    cursor: pointer;
    height: auto;
}