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

:root {
    --primary-color: #0052CC;
    --primary-hover: #0747A6;
    --secondary-color: #6B778C;
    --success-color: #00875A;
    --error-color: #DE350B;
    --warning-color: #FFAB00;
    --background: #FAFBFC;
    --surface: #FFFFFF;
    --text-primary: #172B4D;
    --text-secondary: #5E6C84;
    --border-color: #DFE1E6;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.12);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 25px rgba(0,0,0,0.1);
    --radius: 8px;
    --radius-sm: 4px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: var(--text-primary);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    padding: 40px 0;
    color: white;
    position: relative;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

header .icon {
    font-size: 3rem;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.subtitle {
    font-size: 1.2rem;
    opacity: 0.95;
    font-weight: 300;
}

.language-selector {
    position: absolute;
    top: 0;
    right: 0;
}

.language-selector select {
    padding: 8px 12px;
    border-radius: var(--radius-sm);
    border: 1px solid rgba(255,255,255,0.3);
    background: rgba(255,255,255,0.1);
    color: white;
    font-size: 14px;
    cursor: pointer;
    backdrop-filter: blur(10px);
}

.language-selector select option {
    background: var(--primary-color);
}

main {
    display: grid;
    gap: 20px;
}

.card {
    background: var(--surface);
    border-radius: var(--radius);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    transition: transform 0.2s;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.card-header {
    padding: 20px;
    background: linear-gradient(135deg, #f5f7fa 0%, #e9ecef 100%);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.card-header h2 {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--text-primary);
}

.header-actions {
    display: flex;
    gap: 10px;
}

.card-body {
    padding: 20px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input[type="text"],
.form-group input[type="number"],
.form-group select {
    width: 100%;
    padding: 10px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 14px;
    transition: border-color 0.2s;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.namespace-group {
    background: var(--background);
    padding: 15px;
    border-radius: var(--radius-sm);
    margin-top: 15px;
}

.form-options {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    margin-bottom: 20px;
}

.checkbox {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    user-select: none;
}

.checkbox input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
}

.btn {
    padding: 10px 20px;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
    transform: scale(1.02);
}

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

.btn-secondary:hover {
    background: #5E6C84;
}

.btn-sm {
    padding: 6px 12px;
    font-size: 12px;
}

.uuid-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
    max-height: 400px;
    overflow-y: auto;
}

.uuid-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px;
    background: var(--background);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    transition: all 0.2s;
}

.uuid-item:hover {
    border-color: var(--primary-color);
    background: white;
}

.uuid-text {
    font-family: 'Courier New', monospace;
    font-size: 14px;
    word-break: break-all;
    flex: 1;
}

.btn-copy {
    background: transparent;
    border: none;
    font-size: 20px;
    cursor: pointer;
    padding: 5px;
    transition: transform 0.2s;
}

.btn-copy:hover {
    transform: scale(1.2);
}

.empty-state {
    text-align: center;
    padding: 40px;
    color: var(--text-secondary);
    font-style: italic;
}

.validation-result {
    margin-top: 20px;
}

.validation-success {
    padding: 15px;
    background: #E3FCEF;
    border: 1px solid #00875A;
    border-radius: var(--radius-sm);
    color: #006644;
}

.validation-error {
    padding: 15px;
    background: #FFEBE6;
    border: 1px solid #DE350B;
    border-radius: var(--radius-sm);
    color: #BF2600;
}

.export-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.history-list {
    max-height: 300px;
    overflow-y: auto;
}

.history-item {
    padding: 12px;
    border-bottom: 1px solid var(--border-color);
}

.history-item:last-child {
    border-bottom: none;
}

.history-date {
    font-size: 12px;
    color: var(--text-secondary);
    margin-bottom: 5px;
}

.history-uuids {
    font-family: 'Courier New', monospace;
    font-size: 12px;
    color: var(--text-primary);
    word-break: break-all;
}

footer {
    text-align: center;
    padding: 40px 0 20px;
    color: white;
    opacity: 0.9;
}

.toast {
    position: fixed;
    bottom: 20px;
    right: 20px;
    padding: 15px 20px;
    border-radius: var(--radius-sm);
    color: white;
    font-weight: 500;
    z-index: 1000;
    transform: translateX(400px);
    transition: transform 0.3s;
}

.toast.show {
    transform: translateX(0);
}

.toast.success {
    background: var(--success-color);
}

.toast.error {
    background: var(--error-color);
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--background);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb {
    background: var(--secondary-color);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

/* Responsive */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .container {
        padding: 10px;
    }
    
    .card-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
    
    .header-actions {
        width: 100%;
        justify-content: flex-end;
    }
    
    .form-options {
        flex-direction: column;
    }
    
    .export-buttons {
        flex-direction: column;
    }
    
    .export-buttons .btn {
        width: 100%;
    }
    
    .language-selector {
        position: static;
        margin-top: 20px;
    }
}

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

.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255,255,255,.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}