:root {
    --color-primary: #0052CC;
    --color-secondary: #00875A;
    --color-bg: #FFFFFF;
    --color-bg-sidebar: #F4F5F7;
    --color-text: #172B4D;
    --color-text-light: #6B778C;
    --color-border: #DFE1E6;
    --card-bg: #FFFFFF;
    --card-hover-border: rgba(0, 82, 204, 0.1);
    --spacing-unit: 8px;
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif;
}

[data-theme="dark"] {
    --color-primary: #4C9AFF;
    --color-secondary: #57D9A3;
    --color-bg: #1B2631;
    --color-bg-sidebar: #2C3E50;
    --color-text: #ECF0F1;
    --color-text-light: #BDC3C7;
    --color-border: #4a5c6e;
    --card-bg: #34495E;
    --card-hover-border: rgba(76, 154, 255, 0.3);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: var(--font-family);
    background-color: var(--color-bg);
    color: var(--color-text);
    display: flex;
    height: 100vh;
    overflow: hidden;
}

#app {
    display: flex;
    width: 100%;
}

/* Sidebar */
.sidebar {
    width: 250px;
    background-color: var(--color-bg-sidebar);
    border-right: 1px solid var(--color-border);
    padding: calc(var(--spacing-unit) * 2);
    display: flex;
    flex-direction: column;
}

.sidebar h2 {
    font-size: 16px;
    text-transform: uppercase;
    color: var(--color-text-light);
    margin-bottom: calc(var(--spacing-unit) * 2);
}

.category-list {
    list-style: none;
    padding: 0;
}

.category-item {
    padding: var(--spacing-unit);
    border-radius: 3px;
    cursor: pointer;
    display: flex;
    align-items: center;
    color: var(--color-text);
    margin-bottom: 4px;
    font-size: 16px;
    font-weight: 500;
}

.category-item.active {
    background-color: var(--color-border);
}

.category-item:hover {
    background-color: var(--color-border);
    opacity: 0.8;
}

.category-item .icon {
    margin-right: var(--spacing-unit);
}

/* Main Content */
.main-content {
    flex: 1;
    padding: calc(var(--spacing-unit) * 4);
    overflow-y: auto;
}

.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: calc(var(--spacing-unit) * 3);
}

/* Bookmark Card - Premium Design */
.bookmark-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 20px;
}

.bookmark-card {
    background: var(--card-bg);
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    text-decoration: none;
    color: inherit;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    position: relative;
    border: 2px solid var(--color-border);
    height: 100%;
}

.bookmark-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.1);
    border-color: var(--card-hover-border);
}

.bookmark-visual {
    height: 140px;
    background-color: var(--color-bg-sidebar);
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.bookmark-visual img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.bookmark-visual img.is-favicon {
    width: 48px;
    height: 48px;
    object-fit: contain;
}

.bookmark-card:hover .bookmark-visual img:not(.is-favicon) {
    transform: scale(1.05);
}

.bookmark-info {
    padding: 16px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.bookmark-title {
    font-size: 15px;
    font-weight: 600;
    line-height: 1.4;
    color: var(--color-text);
    margin-bottom: 6px;

    /* Multi-line truncation */
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    text-overflow: ellipsis;
}

.bookmark-meta {
    margin-top: auto;
    display: flex;
    align-items: center;
    color: var(--color-text-light);
    font-size: 12px;
}

.bookmark-hostname {
    display: flex;
    align-items: center;
}

.bookmark-footer {
    padding: 0 16px 12px 16px;
    display: flex;
    justify-content: flex-end;
    gap: 8px;
    opacity: 0;
    transition: opacity 0.2s ease;
    transform: translateY(5px);
}

.bookmark-card:hover .bookmark-footer {
    opacity: 1;
    transform: translateY(0);
}

/* Action Buttons */
.action-btn {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    border: 1px solid var(--color-border);
    background-color: var(--color-bg);
    color: var(--color-text-light);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
    padding: 0;
}

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

.action-btn.delete-btn:hover {
    background-color: #FFEDEB;
    color: #DE350B;
}

.action-btn svg {
    width: 16px;
    height: 16px;
    fill: currentColor;
}

/* Components */
.btn {
    background-color: var(--color-primary);
    color: white;
    border: none;
    padding: 8px 16px;
    border-radius: 3px;
    cursor: pointer;
    font-weight: 500;
}

.theme-toggle {
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text);
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    margin-right: 10px;
    transition: all 0.2s;
}

.theme-toggle:hover {
    background-color: var(--color-border);
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
    fill: currentColor;
}

.btn:hover {
    background-color: #0065FF;
}

.input-group {
    margin-bottom: 10px;
}

.input-group input,
.input-group select {
    width: 100%;
    padding: 8px;
    border: 1px solid var(--color-border);
    border-radius: 3px;
    box-sizing: border-box;
    background-color: var(--color-bg);
    color: var(--color-text);
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: none;
    justify-content: center;
    align-items: center;
}

.modal.open {
    display: flex;
}

.modal-content {
    background: var(--color-bg);
    border: 1px solid var(--color-border);
    color: var(--color-text);
    padding: 20px;
    border-radius: 4px;
    width: 400px;
}

/* Search Input */
.search-input {
    width: 100%;
    padding: 8px 16px;
    border: 1px solid var(--color-border);
    border-radius: 20px;
    background-color: var(--color-bg-sidebar);
    color: var(--color-text);
    font-size: 14px;
    transition: all 0.2s;
    outline: none;
}

.search-input:focus {
    background-color: white;
    box-shadow: 0 0 0 2px var(--color-primary);
    border-color: transparent;
}