:root {
    --bg-primary: #1a1a2e;
    --bg-secondary: #16213e;
    --bg-tertiary: #0f3460;
    --text-primary: #eaeaea;
    --text-secondary: #a0a0a0;
    --accent: #e94560;
    --accent-hover: #ff6b6b;
    --success: #4ecca3;
    --warning: #ffa502;
    --error: #ff4757;
    --border: #2d2d44;
    --shadow: rgba(0, 0, 0, 0.3);
    --radius: 8px;
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    background: var(--bg-secondary);
    padding: var(--spacing-md);
    text-align: center;
    border-bottom: 2px solid var(--border);
    box-shadow: 0 2px 8px var(--shadow);
}

.header h1 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.container {
    flex: 1;
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    padding: var(--spacing-md);
}

.input-section {
    background: var(--bg-secondary);
    padding: var(--spacing-md);
    border-radius: var(--radius);
    margin-bottom: var(--spacing-md);
    box-shadow: 0 2px 8px var(--shadow);
}

.url-textarea {
    width: 100%;
    background: var(--bg-primary);
    color: var(--text-primary);
    border: 2px solid var(--border);
    border-radius: var(--radius);
    padding: var(--spacing-sm);
    font-family: inherit;
    font-size: 1rem;
    resize: vertical;
    min-height: 100px;
    transition: border-color 0.2s;
}

.url-textarea:focus {
    outline: none;
    border-color: var(--accent);
}

.button-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-sm);
}

.btn {
    padding: var(--spacing-sm) var(--spacing-md);
    border: none;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    text-align: center;
}

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

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
}

.btn-primary:disabled {
    background: var(--border);
    cursor: not-allowed;
    transform: none;
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 2px solid var(--border);
}

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

.btn-small {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.875rem;
}

.active-section,
.history-section {
    background: var(--bg-secondary);
    padding: var(--spacing-md);
    border-radius: var(--radius);
    margin-bottom: var(--spacing-md);
    box-shadow: 0 2px 8px var(--shadow);
}

h2 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.collapsible {
    cursor: pointer;
    user-select: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.toggle-icon {
    transition: transform 0.2s;
}

.collapsed .toggle-icon {
    transform: rotate(-90deg);
}

.downloads-list,
.history-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.hidden {
    display: none;
}

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

.download-item,
.history-item {
    background: var(--bg-primary);
    padding: var(--spacing-sm);
    border-radius: var(--radius);
    border: 1px solid var(--border);
}

.item-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--spacing-xs);
    gap: var(--spacing-sm);
}

.item-title {
    font-weight: 500;
    color: var(--text-primary);
    word-break: break-word;
    flex: 1;
}

.item-domain {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.item-status {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.status-icon {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    display: inline-block;
}

.status-pending {
    background: var(--warning);
}

.status-processing {
    background: var(--accent);
    animation: pulse 1.5s infinite;
}

.status-completed {
    background: var(--success);
}

.status-failed {
    background: var(--error);
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--bg-tertiary);
    border-radius: 4px;
    overflow: hidden;
    margin: var(--spacing-xs) 0;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent), var(--accent-hover));
    transition: width 0.3s ease;
    border-radius: 4px;
}

.item-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-top: var(--spacing-xs);
}

.btn-cancel {
    background: var(--error);
    color: white;
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.875rem;
}

.btn-cancel:hover {
    background: #ff6b6b;
}

.status-bar {
    background: var(--bg-secondary);
    padding: var(--spacing-sm) var(--spacing-md);
    border-top: 2px solid var(--border);
    display: flex;
    justify-content: space-around;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    font-size: 0.875rem;
}

.status-item {
    color: var(--text-secondary);
}

.status-item span {
    color: var(--text-primary);
    font-weight: 600;
}

.toast-container {
    position: fixed;
    top: var(--spacing-md);
    right: var(--spacing-md);
    z-index: 1000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    max-width: 400px;
}

.toast {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius);
    box-shadow: 0 4px 12px var(--shadow);
    border-left: 4px solid var(--accent);
    animation: slideIn 0.3s ease;
}

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

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

.toast-warning {
    border-left-color: var(--warning);
}

@keyframes slideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

@media (min-width: 768px) {
    .header h1 {
        font-size: 2rem;
    }

    .button-group {
        flex-direction: row;
    }

    .btn {
        flex: 1;
    }

    .item-header {
        flex-direction: row;
    }
}

@media (max-width: 767px) {
    .container {
        padding: var(--spacing-sm);
    }

    .input-section,
    .active-section,
    .history-section {
        padding: var(--spacing-sm);
    }

    .status-bar {
        flex-direction: column;
        text-align: center;
    }
}