:root {
    --bg-primary: #0f0f0f;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #252525;
    --border-color: #333;
    --text-primary: #e0e0e0;
    --text-secondary: #a0a0a0;
    --accent: #6c5ce7;
    --accent-hover: #7f6ff0;
    --success: #00b894;
    --danger: #e74c3c;
    --radius: 10px;
    --font: 'Segoe UI', system-ui, -apple-system, sans-serif;
}

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

body {
    font-family: var(--font);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    padding: 20px;
    line-height: 1.6;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
}

header {
    text-align: center;
    margin-bottom: 30px;
}

header h1 {
    font-size: 2rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--accent), #a29bfe);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 6px;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.main-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    margin-bottom: 20px;
}

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

.panel {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    padding: 20px;
}

label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

textarea {
    width: 100%;
    height: 220px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 12px;
    color: var(--text-primary);
    font-family: var(--font);
    font-size: 0.95rem;
    resize: vertical;
    outline: none;
    transition: border-color 0.2s;
}

textarea:focus {
    border-color: var(--accent);
}

textarea::placeholder {
    color: #555;
}

.options {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    margin: 14px 0;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 400;
    color: var(--text-primary);
    font-size: 0.9rem;
    cursor: pointer;
}

.checkbox-label input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: var(--accent);
    cursor: pointer;
}

.seed-group {
    margin-bottom: 14px;
}

.seed-group input {
    width: 100%;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 10px 12px;
    color: var(--text-primary);
    font-family: var(--font);
    font-size: 0.95rem;
    outline: none;
    transition: border-color 0.2s;
}

.seed-group input:focus {
    border-color: var(--accent);
}

.seed-group input::placeholder {
    color: #555;
}

.button-group {
    display: flex;
    gap: 10px;
}

.btn-primary {
    flex: 1;
    background: var(--accent);
    color: #fff;
    border: none;
    padding: 12px 20px;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s, transform 0.1s;
}

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

.btn-primary:active {
    transform: scale(0.98);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    padding: 12px 20px;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.2s, border-color 0.2s;
}

.btn-secondary:hover {
    background: #333;
    border-color: #555;
}

.output-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}

.output-actions {
    display: flex;
    gap: 8px;
}

.btn-icon {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    width: 36px;
    height: 36px;
    border-radius: 8px;
    font-size: 1.1rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s, border-color 0.2s;
}

.btn-icon:hover {
    background: #333;
    border-color: #555;
}

.output-list {
    min-height: 260px;
    max-height: 500px;
    overflow-y: auto;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 12px;
}

.output-list .placeholder {
    color: #555;
    font-style: italic;
    text-align: center;
    padding-top: 100px;
}

.output-item {
    padding: 8px 12px;
    border-bottom: 1px solid var(--border-color);
    font-size: 0.95rem;
    display: flex;
    align-items: center;
    gap: 10px;
    animation: fadeIn 0.3s ease;
}

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

.output-item .index {
    color: var(--text-secondary);
    font-weight: 600;
    min-width: 28px;
    font-size: 0.85rem;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-4px); }
    to { opacity: 1; transform: translateY(0); }
}

.history-panel {
    margin-top: 0;
}

.history-panel h3 {
    font-size: 1rem;
    margin-bottom: 12px;
    color: var(--text-secondary);
}

.history-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.history-item {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 10px 14px;
    font-size: 0.88rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    transition: border-color 0.2s;
}

.history-item:hover {
    border-color: var(--accent);
}

.history-item .history-preview {
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 70%;
}

.history-item .history-time {
    color: var(--text-secondary);
    font-size: 0.8rem;
}

.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(20px);
    background: var(--success);
    color: #fff;
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.95rem;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s, transform 0.3s;
    z-index: 999;
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* Fullscreen mode */
body.fullscreen-mode .container {
    max-width: 100%;
}

body.fullscreen-mode .output-list {
    max-height: 80vh;
    min-height: 60vh;
    font-size: 1.2rem;
}

body.fullscreen-mode .output-item {
    padding: 12px 16px;
}