:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --background-color: #f8fafc;
    --card-background: #ffffff;
    --text-color: #1e293b;
    --border-color: #e2e8f0;
    --button-text: #ffffff;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --editor-background: #ffffff;
    --success-color: #059669;
    --error-color: #dc2626;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1rem;
    width: 100%;
    display: grid;
    grid-template-columns: 400px 1fr;
    gap: 2rem;
}

.controls-panel {
    background: var(--card-background);
    border-radius: 1rem;
    box-shadow: 0 4px 6px var(--shadow-color);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    height: fit-content;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.control-group label {
    font-weight: 500;
    color: var(--text-color);
    font-size: 0.875rem;
}

.select-wrapper {
    position: relative;
}

.select-wrapper::after {
    content: '';
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    width: 0.75rem;
    height: 0.75rem;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%231e293b'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
    background-size: contain;
    background-repeat: no-repeat;
    pointer-events: none;
}

select {
    width: 100%;
    padding: 0.75rem 1rem;
    font-size: 0.875rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    background: var(--card-background);
    color: var(--text-color);
    appearance: none;
    cursor: pointer;
}

select:focus {
    outline: none;
    border-color: var(--primary-color);
}

optgroup {
    font-weight: 600;
    color: #64748b;
}

.editor-wrapper {
    height: 100px;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    overflow: hidden;
}

#editor {
    height: 100%;
    width: 100%;
}

.format-hint {
    font-size: 0.75rem;
    color: #64748b;
}

.range-group {
    display: flex;
    align-items: center;
    gap: 1rem;
}

input[type="range"] {
    flex: 1;
    height: 6px;
    background: var(--border-color);
    border-radius: 3px;
    outline: none;
    -webkit-appearance: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 18px;
    height: 18px;
    background: var(--primary-color);
    border-radius: 50%;
    cursor: pointer;
    transition: background 0.2s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
    background: var(--primary-hover);
}

#sizeValue {
    font-size: 0.875rem;
    color: var(--text-color);
    min-width: 3ch;
    text-align: right;
}

.color-presets {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.preset-group {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.preset-group > span {
    font-size: 0.75rem;
    color: #64748b;
    font-weight: 500;
}

.preset-buttons {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(80px, 1fr));
    gap: 0.75rem;
}

.preset-btn {
    background: var(--card-background);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    padding: 0.75rem;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.2s ease;
}

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

.preset-btn.active {
    border-color: var(--primary-color);
    background: var(--background-color);
}

.preview-bar {
    width: 40px;
    height: 24px;
    border-radius: 0.25rem;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    gap: 2px;
    padding: 2px;
    background: var(--border-color);
}

.preview-bar .dark,
.preview-bar .light {
    flex: 1;
    border-radius: 1px;
}

.preview-bar .dark {
    background-color: var(--dark-color);
}

.preview-bar .light {
    background-color: var(--light-color);
}

.preset-btn span {
    font-size: 0.75rem;
    color: var(--text-color);
}

.custom-colors {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    padding-top: 0.5rem;
    border-top: 1px solid var(--border-color);
}

.custom-colors > span {
    font-size: 0.75rem;
    color: #64748b;
    font-weight: 500;
}

.color-inputs {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
}

.color-input {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    align-items: center;
}

.color-input span {
    font-size: 0.75rem;
    color: #64748b;
}

input[type="color"] {
    -webkit-appearance: none;
    width: 100%;
    height: 40px;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    cursor: pointer;
    padding: 2px;
    background: var(--card-background);
}

input[type="color"]::-webkit-color-swatch-wrapper {
    padding: 0;
}

input[type="color"]::-webkit-color-swatch {
    border: none;
    border-radius: 0.25rem;
}

.checkbox-group {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.checkbox {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    cursor: pointer;
}

.checkbox input {
    width: 16px;
    height: 16px;
    border-radius: 4px;
    cursor: pointer;
}

.btn {
    background-color: var(--card-background);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 0.75rem 1rem;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s ease;
    font-weight: 500;
}

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

.btn.primary {
    background-color: var(--primary-color);
    color: var(--button-text);
    border-color: var(--primary-color);
}

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

.btn.secondary {
    background-color: var(--background-color);
}

.preview-panel {
    background: var(--card-background);
    border-radius: 1rem;
    box-shadow: 0 4px 6px var(--shadow-color);
    padding: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
}

.barcode-container {
    background: var(--card-background);
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: 0 2px 4px var(--shadow-color);
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
    min-height: 200px;
    border: 1px solid var(--border-color);
}

#barcode {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
    min-height: 120px;
    background: var(--background-color);
    border-radius: 0.5rem;
    padding: 1rem;
}

#barcode svg {
    max-width: 100%;
    height: 100%;
    min-height: 100px;
}

.info-text {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    text-align: center;
}

.validation-status {
    font-weight: 500;
    min-height: 1.5em;
    text-align: center;
}

.validation-status.valid {
    color: var(--success-color);
}

.validation-status.invalid {
    color: var(--error-color);
    max-width: 300px;
    margin: 0 auto;
}

.format-hint {
    font-size: 0.875rem;
    color: var(--error-color);
    text-align: center;
    min-height: 1.5em;
    padding: 0.25rem 0;
    font-weight: 500;
}

.format-info {
    color: #64748b;
    font-size: 0.875rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.copy-example {
    background: none;
    border: none;
    color: var(--primary-color);
    cursor: pointer;
    padding: 0.25rem;
    display: inline-flex;
    align-items: center;
    transition: color 0.2s ease;
}

.copy-example:hover {
    color: var(--primary-hover);
}

.copy-example svg {
    width: 1rem;
    height: 1rem;
    pointer-events: none;
}

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