:root {
    --primary-bg: #1e1e1e;
    --secondary-bg: #252526;
    --card-bg: #2d2d30;
    --entry-bg: #333333;
    --text-color: #d4d4d4;
    --text-color-darker: #8b8b8b;
    --select-bg: linear-gradient(135deg, #094771 0%, #0a5a8a 100%);
    --btn-bg: linear-gradient(135deg, #0e639c 0%, #1177bb 100%);
    --btn-hover-bg: linear-gradient(135deg, #1177bb 0%, #1a8cd8 100%);
    --border-color: #3c3c3c;
    --header-color: #ffffff;
    --success-color: #4CAF50;
    --accent-color: #1177bb;
    --favorite-color: #ffd700;
    --warning-color: #ff9800;
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 20px rgba(17, 119, 187, 0.3);
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --transition-speed: 0.3s;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
}

*, *::before, *::after {
    box-sizing: border-box;
}

body {
    font-family: var(--font-family);
    margin: 0;
    background: linear-gradient(180deg, #1a1a1a 0%, #1e1e1e 100%);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 40px 30px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

h1 {
    color: var(--header-color);
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 10px;
    letter-spacing: -0.5px;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.subtitle {
    text-align: center;
    color: var(--text-color-darker);
    font-size: 1.1rem;
    margin-bottom: 40px;
    font-weight: 400;
}

h2 {
    color: var(--header-color);
    font-size: 1.4rem;
    font-weight: 600;
    margin: 0 0 20px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--accent-color);
    letter-spacing: -0.3px;
}

.top-section {
    display: flex;
    justify-content: space-between;
    align-items: stretch;
    margin-bottom: 20px;
    gap: 15px;
}

.search-container {
    flex-grow: 1;
    position: relative;
}

.search-container::before {
    content: "🔍";
    position: absolute;
    left: 18px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.2rem;
    pointer-events: none;
    opacity: 0.6;
}

.search-box {
    width: 100%;
    padding: 16px 50px;
    border-radius: var(--radius-md);
    border: 2px solid var(--border-color);
    background-color: var(--card-bg);
    color: var(--text-color);
    font-size: 1.05rem;
    transition: all var(--transition-speed) ease;
    box-shadow: var(--shadow-sm);
}

.search-box:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 4px rgba(17, 119, 187, 0.2), var(--shadow-md);
    transform: translateY(-1px);
}

.search-box::placeholder {
    color: var(--text-color-darker);
}

.clear-search-button {
    position: absolute;
    right: 18px;
    top: 50%;
    transform: translateY(-50%);
    width: 24px;
    height: 24px;
    border: none;
    background: transparent;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s, visibility 0.2s;
    padding: 0;
}

.clear-search-button::before,
.clear-search-button::after {
    content: '';
    position: absolute;
    left: 50%;
    top: 50%;
    width: 16px;
    height: 2px;
    background-color: var(--text-color-darker);
    transform-origin: center;
    transition: background-color 0.2s;
}

.clear-search-button::before {
    transform: translate(-50%, -50%) rotate(45deg);
}

.clear-search-button::after {
    transform: translate(-50%, -50%) rotate(-45deg);
}

.clear-search-button:hover::before,
.clear-search-button:hover::after {
    background-color: var(--text-color);
}

.search-container.has-text .clear-search-button {
    opacity: 0.7;
    visibility: visible;
}

.search-container.has-text .clear-search-button:hover {
    opacity: 1;
}

#toggle-list-button {
    padding: 16px 32px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--card-bg);
    color: var(--text-color);
    font-size: 1.05rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    box-shadow: var(--shadow-sm);
    white-space: nowrap;
}

#toggle-list-button:hover {
    background: var(--entry-bg);
    border-color: var(--accent-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

#toggle-list-button:active {
    transform: translateY(0);
}

.item-count {
    font-size: 1.05rem;
    color: var(--text-color-darker);
    margin-bottom: 20px;
    min-height: 1.5em;
    font-weight: 500;
    padding-left: 4px;
}

.main-content {
    display: grid;
    grid-template-columns: 1fr 380px;
    gap: 30px;
    max-height: 700px;
    height: 700px;
}

.list-frame, .controls-frame {
    background: var(--card-bg);
    padding: 28px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-md);
    transition: box-shadow var(--transition-speed) ease;
    height: 100%;
    overflow: hidden;
}

.list-frame:hover, .controls-frame:hover {
    box-shadow: var(--shadow-lg);
}

.panel {
    flex: 1;
    overflow-y: auto;
    margin: 0 -10px 0 0;
    padding-right: 10px;
    min-height: 0;
}

.list-frame .panel {
    display: none;
}

.list-frame.visible .panel {
    display: block;
}

.item-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 8px;
}

.item-item {
    padding: 16px 20px;
    background: var(--secondary-bg);
    border: 2px solid transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.item-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: var(--accent-color);
    transform: scaleY(0);
    transition: transform 0.2s ease;
}

.item-item:hover {
    background: var(--entry-bg);
    border-color: var(--border-color);
    transform: translateX(4px);
}

.item-item:hover::before {
    transform: scaleY(1);
}

.item-item.selected {
    background: var(--select-bg);
    border-color: var(--accent-color);
    color: white;
    transform: translateX(4px);
    box-shadow: var(--shadow-sm);
}

.item-item.selected::before {
    transform: scaleY(1);
}

.item-title {
    font-weight: 500;
    font-size: 1.05rem;
}

.item-title .highlight {
    color: #ffc66d;
    font-weight: 700;
    background: rgba(255, 198, 109, 0.15);
    padding: 2px 4px;
    border-radius: 3px;
}

.item-id {
    color: var(--text-color-darker);
    font-size: 0.95rem;
    font-family: 'Courier New', monospace;
    background: rgba(0, 0, 0, 0.3);
    padding: 4px 10px;
    border-radius: 6px;
}

.item-item.selected .item-id {
    color: rgba(255, 255, 255, 0.9);
    background: rgba(0, 0, 0, 0.2);
}

.controls-frame {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

label {
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--header-color);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 4px;
}

.quantity-controls {
    display: flex;
    align-items: center;
    gap: 6px;
}

.quantity-button {
    width: 48px;
    height: 52px;
    border: 2px solid var(--border-color);
    background: var(--secondary-bg);
    color: var(--text-color);
    font-size: 1.5rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-speed) ease;
    display: flex;
    align-items: center;
    justify-content: center;
    padding-bottom: 2px;
}

.quantity-button:hover {
    background: var(--entry-bg);
    border-color: var(--accent-color);
}

.quantity-button:active {
    transform: translateY(1px);
}

#quantity-input {
    flex-grow: 1;
    height: 52px;
    text-align: center;
    padding: 14px 16px;
    border-radius: var(--radius-sm);
    border: 2px solid var(--border-color);
    background-color: var(--secondary-bg);
    color: var(--text-color);
    font-size: 1.05rem;
    transition: all var(--transition-speed) ease;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.3);
    -moz-appearance: textfield;
}

#quantity-input::-webkit-outer-spin-button,
#quantity-input::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

#quantity-input:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 4px rgba(17, 119, 187, 0.2), inset 0 2px 4px rgba(0, 0, 0, 0.3);
}

#copy-button {
    width: 100%;
    padding: 16px;
    border: none;
    border-radius: var(--radius-md);
    background: var(--btn-bg);
    color: white;
    font-size: 1.1rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s ease;
    box-shadow: var(--shadow-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    position: relative;
    overflow: hidden;
}

#copy-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

#copy-button:hover:not(:disabled) {
    background: var(--btn-hover-bg);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

#copy-button:hover:not(:disabled)::before {
    left: 100%;
}

#copy-button:active:not(:disabled) {
    transform: translateY(0);
}

#copy-button:disabled {
    background: var(--entry-bg);
    color: var(--text-color-darker);
    cursor: not-allowed;
    opacity: 0.6;
}

#copy-button.success {
    background: linear-gradient(135deg, var(--success-color) 0%, #66bb6a 100%);
    animation: successPulse 0.4s ease;
}

@keyframes successPulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.03); }
}

#status-label {
    margin-top: 8px;
    font-size: 0.95rem;
    color: var(--text-color-darker);
    min-height: 1.5em;
    text-align: center;
    padding: 12px;
    border-radius: var(--radius-sm);
    background: var(--secondary-bg);
    font-weight: 500;
    transition: all 0.3s ease;
}

#status-label:not(:empty) {
    border: 1px solid var(--border-color);
}

::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: var(--secondary-bg);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, #555 0%, #666 100%);
    border-radius: 5px;
    border: 2px solid var(--secondary-bg);
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(180deg, #666 0%, #777 100%);
}

@media (max-width: 1024px) {
    .main-content {
        grid-template-columns: 1fr;
        max-height: none;
        height: auto;
    }

    .list-frame {
        height: 600px;
    }

    .controls-frame {
        max-width: 600px;
        margin: 0 auto;
        width: 100%;
        height: auto;
    }

    .stats-section {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 768px) {
    .container {
        padding: 30px 20px;
    }

    .top-section {
        flex-direction: column;
    }

    h1 {
        font-size: 2rem;
    }

    .subtitle {
        font-size: 1rem;
        margin-bottom: 30px;
    }

    #toggle-list-button {
        width: 100%;
    }

    .list-frame {
        height: 500px;
    }

    .filter-tabs {
        justify-content: stretch;
    }

    .filter-tab {
        flex: 1;
        text-align: center;
        padding: 10px 12px;
        font-size: 0.9rem;
    }

    .filter-tab .badge {
        display: block;
        margin: 4px auto 0;
    }

    .stats-section {
        grid-template-columns: repeat(3, 1fr);
        gap: 8px;
        padding: 12px;
    }

    .stat-item {
        padding: 10px 8px;
    }

    .stat-value {
        font-size: 1.5rem;
    }

    .stat-label {
        font-size: 0.75rem;
    }

    .quick-actions {
        flex-direction: column;
    }

    .quick-action-btn {
        width: 100%;
    }

    .item-item {
        padding: 14px 16px;
        padding-right: 45px;
    }

    .item-title {
        font-size: 1rem;
    }

    .item-id {
        font-size: 0.85rem;
        padding: 3px 8px;
    }

    .item-category-tag {
        font-size: 0.7rem;
        padding: 2px 6px;
    }

    .shortcuts-hint {
        padding: 14px;
    }

    .shortcut-item {
        font-size: 0.8rem;
        padding: 5px 0;
    }

    .toast {
        bottom: 20px;
        right: 20px;
        left: 20px;
        max-width: none;
        font-size: 0.95rem;
    }
}

@media (max-width: 480px) {
    h1 {
        font-size: 1.7rem;
    }

    .subtitle {
        font-size: 0.95rem;
    }

    .container {
        padding: 20px 15px;
    }

    .stats-section {
        grid-template-columns: 1fr;
        gap: 8px;
    }

    .stat-item {
        display: grid;
        grid-template-columns: auto 1fr;
        gap: 12px;
        text-align: left;
        align-items: center;
    }

    .stat-value {
        font-size: 2rem;
    }

    .stat-label {
        text-align: left;
    }

    .search-box {
        font-size: 1rem;
        padding: 14px 45px;
    }

    #toggle-list-button {
        font-size: 1rem;
        padding: 14px 24px;
    }

    .filter-tabs {
        gap: 6px;
    }

    .filter-tab {
        font-size: 0.85rem;
        padding: 8px 10px;
    }

    .list-frame, .controls-frame {
        padding: 20px;
    }

    .list-frame {
        height: 450px;
    }

    h2 {
        font-size: 1.2rem;
        margin-bottom: 16px;
    }

    .item-item {
        flex-direction: column;
        align-items: flex-start;
        padding: 12px 14px;
        padding-right: 14px;
        gap: 8px;
    }

    .item-meta {
        width: 100%;
        justify-content: space-between;
    }

    .favorite-btn {
        top: 12px;
        right: 10px;
        transform: none;
        font-size: 1.3rem;
    }

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

    .item-item.selected::after {
        top: 12px;
        right: 35px;
        transform: scale(1);
    }

    .quantity-controls {
        gap: 8px;
    }

    .quantity-button {
        width: 56px;
        height: 50px;
    }

    #quantity-input {
        height: 50px;
        font-size: 1rem;
    }

    #copy-button {
        font-size: 1rem;
        padding: 14px;
    }
}

.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    padding: 60px 20px;
    text-align: center;
    color: var(--text-color-darker);
}

.empty-state-icon {
    font-size: 5rem;
    margin-bottom: 24px;
    opacity: 0.4;
    transform: scale(0.95);
    animation: float 4s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0) scale(0.95); }
    50% { transform: translateY(-10px) scale(1); }
}

.empty-state-text {
    font-size: 1.25rem;
    font-weight: 500;
}

/* Favorites and Recent Items Styles */
.favorite-btn {
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    padding: 8px;
    opacity: 0.4;
    transition: all 0.2s ease;
    z-index: 10;
    line-height: 1;
}

.favorite-btn:hover {
    opacity: 0.8;
    transform: translateY(-50%) scale(1.2);
}

.favorite-btn.is-favorite {
    opacity: 1;
    animation: heartBeat 0.4s ease;
}

@keyframes heartBeat {
    0%, 100% { transform: translateY(-50%) scale(1); }
    25% { transform: translateY(-50%) scale(1.3); }
    50% { transform: translateY(-50%) scale(1.1); }
}

.item-item.is-favorite {
    border-left: 3px solid var(--favorite-color);
}

/* Filter Tabs */
.filter-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}

.filter-tab {
    padding: 10px 18px;
    background: var(--secondary-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-color);
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 0.95rem;
    font-weight: 600;
    white-space: nowrap;
    position: relative;
    overflow: hidden;
}

.filter-tab::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(17, 119, 187, 0.2), transparent);
    transition: left 0.3s ease;
}

.filter-tab:hover {
    background: var(--entry-bg);
    border-color: var(--accent-color);
    transform: translateY(-1px);
}

.filter-tab:hover::before {
    left: 100%;
}

.filter-tab.active {
    background: var(--btn-bg);
    border-color: var(--accent-color);
    color: white;
    box-shadow: var(--shadow-sm);
}

.filter-tab .badge {
    display: inline-block;
    background: rgba(255, 255, 255, 0.2);
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 0.85rem;
    margin-left: 6px;
    font-weight: 700;
}

.filter-tab.active .badge {
    background: rgba(255, 255, 255, 0.3);
}

/* Stats and Info Section */
.stats-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 12px;
    margin-bottom: 20px;
    padding: 16px;
    background: var(--secondary-bg);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

.stat-item {
    text-align: center;
    padding: 12px;
    background: var(--card-bg);
    border-radius: var(--radius-sm);
    transition: all 0.2s ease;
}

.stat-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.stat-value {
    display: block;
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--accent-color);
    line-height: 1;
    margin-bottom: 4px;
}

.stat-label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-color-darker);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}

/* Quick Actions Bar */
.quick-actions {
    display: flex;
    gap: 8px;
    margin-bottom: 16px;
}

.quick-action-btn {
    flex: 1;
    padding: 12px;
    background: var(--secondary-bg);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    color: var(--text-color);
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

.quick-action-btn:hover {
    background: var(--entry-bg);
    border-color: var(--accent-color);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.quick-action-btn:active {
    transform: translateY(0);
}

/* Keyboard Shortcuts Help */
.shortcuts-hint {
    margin-top: auto;
    padding: 16px;
    background: var(--secondary-bg);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    font-size: 0.85rem;
}

.shortcuts-hint h3 {
    margin: 0 0 12px;
    font-size: 0.95rem;
    color: var(--header-color);
    font-weight: 600;
}

.shortcut-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 6px 0;
    color: var(--text-color-darker);
}

.shortcut-key {
    background: var(--entry-bg);
    padding: 4px 8px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 0.85rem;
    border: 1px solid var(--border-color);
    color: var(--text-color);
}

/* Enhanced item display with icons */
.item-item {
    padding: 16px 20px;
    padding-right: 50px;
}

.item-info {
    flex: 1;
    min-width: 0;
}

.item-meta {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-top: 4px;
}

.item-category-tag {
    font-size: 0.75rem;
    padding: 3px 8px;
    background: rgba(17, 119, 187, 0.2);
    border: 1px solid rgba(17, 119, 187, 0.4);
    border-radius: 4px;
    color: var(--accent-color);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.3px;
}

/* Toast Notifications */
.toast {
    position: fixed;
    bottom: 30px;
    right: 30px;
    padding: 16px 24px;
    background: var(--card-bg);
    border: 2px solid var(--accent-color);
    border-radius: var(--radius-md);
    color: var(--text-color);
    box-shadow: var(--shadow-lg), var(--shadow-glow);
    z-index: 1000;
    animation: slideInUp 0.3s ease, slideOutDown 0.3s ease 2.7s;
    max-width: 350px;
    font-weight: 500;
}

.toast.success {
    border-color: var(--success-color);
    box-shadow: var(--shadow-lg), 0 0 20px rgba(76, 175, 80, 0.3);
}

.toast.warning {
    border-color: var(--warning-color);
    box-shadow: var(--shadow-lg), 0 0 20px rgba(255, 152, 0, 0.3);
}

@keyframes slideInUp {
    from {
        transform: translateY(100px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@keyframes slideOutDown {
    from {
        transform: translateY(0);
        opacity: 1;
    }
    to {
        transform: translateY(100px);
        opacity: 0;
    }
}

/* Selection indicator enhancement */
.item-item::after {
    content: '✓';
    position: absolute;
    right: 20px;
    top: 50%;
    transform: translateY(-50%) scale(0);
    font-size: 1.5rem;
    color: white;
    opacity: 0;
    transition: all 0.2s ease;
    pointer-events: none;
}

.item-item.selected::after {
    transform: translateY(-50%) scale(1);
    opacity: 1;
}

/* Loading state */
.loading-spinner {
    display: inline-block;
    width: 40px;
    height: 40px;
    border: 4px solid var(--border-color);
    border-top-color: var(--accent-color);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin: 40px auto;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Enhanced scrollbar for recent/favorites sections */
.panel::-webkit-scrollbar {
    width: 8px;
}

.panel::-webkit-scrollbar-track {
    background: transparent;
}

.panel::-webkit-scrollbar-thumb {
    background: linear-gradient(180deg, var(--accent-color) 0%, #0a5a8a 100%);
    border-radius: 4px;
}

.panel::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(180deg, var(--btn-hover-bg));
}