:root {
    --bg-color: #f8f9fa;
    --surface-color: #ffffff;
    --surface-hover: #f1f3f5;
    --border-color: #dee2e6;
    --text-primary: #212529;
    --text-secondary: #495057;
    --text-tertiary: #868e96;
    --accent-color: #228be6;
    --accent-hover: #1c7ed6;
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.dashboard {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1.5rem 2rem;
}

.dashboard-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.header-left h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.subtitle {
    color: var(--text-tertiary);
    font-size: 0.9rem;
}

.stat-badge {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    padding: 0.5rem 1rem;
    border-radius: 6px;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.95rem;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.02);
}

.stat-label {
    color: var(--text-secondary);
    font-weight: 500;
}

.stat-value {
    color: var(--text-primary);
    font-weight: 700;
}

.controls-bar {
    display: flex;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    align-items: center;
    background: var(--surface-color);
    padding: 0.75rem 1rem;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.02);
}

input[type="text"],
select {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 0.5rem 0.75rem;
    border-radius: 6px;
    font-family: inherit;
    font-size: 0.9rem;
    outline: none;
    transition: all 0.2s ease;
}

input[type="text"]:focus,
select:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(34, 139, 230, 0.1);
}

#search-input {
    width: 300px;
}

.btn {
    padding: 0.5rem 1rem;
    border-radius: 6px;
    font-family: inherit;
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    text-decoration: none;
    outline: none;
}

.btn.primary {
    background-color: var(--accent-color);
    color: #fff;
    margin-left: auto;
}

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

.btn.secondary {
    background: #fff;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn.secondary:hover {
    background: var(--surface-hover);
}

.replies-section {
    margin-top: 1rem;
    padding-top: 0.5rem;
    border-top: 1px solid var(--border-color);
}

.replies-section summary {
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--accent-color);
    outline: none;
    user-select: none;
}

.replies-container {
    margin-top: 0.75rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.reply-item {
    position: relative;
    padding-left: 1.2rem;
    border-left: 2px solid var(--border-color);
    margin-bottom: 0.5rem;
}

.collapse-toggle {
    position: absolute;
    left: 0.1rem;
    top: 0.2rem;
    background: transparent;
    border: none;
    font-size: 0.75rem;
    color: var(--text-tertiary);
    cursor: pointer;
    width: 1rem;
    height: 1.2rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: transform 0.2s ease, color 0.2s ease;
    outline: none;
    z-index: 1;
}

.collapse-toggle:hover {
    color: var(--text-primary);
}

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

.reply-body {
    display: flex;
    flex-direction: column;
}

.reply-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 0.5rem;
}

.reply-title {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.reply-badge-wrapper {
    margin-bottom: 0.25rem;
}

.reply-type {
    color: var(--text-primary);
}

.reply-type-badge {
    display: inline-block;
    padding: 0.2rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: bold;
    color: white;
}

.badge-red {
    background-color: #e03131;
}

.badge-green {
    background-color: #2f9e44;
}

.badge-blue {
    background-color: #1971c2;
}

.badge-purple {
    background-color: #9c36b5;
}

.badge-gray {
    background-color: #868e96;
}

.reply-date {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.reply-meta {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.reply-authors,
.reply-readers {
    margin-bottom: 0.1rem;
}

.reply-content {
    font-size: 0.9rem;
    color: var(--text-primary);
    white-space: pre-wrap;
    background: var(--surface-hover);
    padding: 0.5rem;
    border-radius: 4px;
}

.reply-children {
    margin-top: 0.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.collapsed-indicator {
    margin-top: 0.5rem;
    font-size: 0.85rem;
    color: var(--text-tertiary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.collapsed-indicator .dots {
    font-weight: bold;
}

.show-collapsed-link {
    color: var(--accent-color);
    text-decoration: none;
    font-weight: 500;
}

.show-collapsed-link:hover {
    text-decoration: underline;
}

/* Global Actions */
.global-actions {
    margin-top: 1rem;
    border-top: 1px solid var(--border-color);
    padding-top: 1rem;
    margin-bottom: 1rem;
    display: flex;
    justify-content: flex-start;
}

#toggle-all-replies-btn {
    font-size: 0.9rem;
    padding: 0.6rem 1.2rem;
}

.sort-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    margin-bottom: 0.75rem;
    background: var(--surface-hover);
    border-radius: 8px;
    border: 1px solid var(--border-color);
    overflow-x: auto;
}

.sort-label {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 600;
    margin-right: 0.5rem;
}

.sort-btn {
    background: transparent;
    border: none;
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
    cursor: pointer;
    padding: 0.4rem 0.6rem;
    border-radius: 6px;
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    transition: all 0.2s ease;
    font-family: inherit;
    white-space: nowrap;
}

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

.sort-btn.active {
    color: var(--accent-color);
    background: rgba(34, 139, 230, 0.1);
    font-weight: 600;
}

.sort-arrow {
    display: inline-block;
    width: 12px;
    font-size: 0.8rem;
    text-align: center;
}

.papers-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.paper-item {
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 1rem 1.25rem;
    transition: box-shadow 0.2s ease;
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    align-items: flex-start;
    justify-content: space-between;
    column-gap: 1.5rem;
    row-gap: 0.5rem;
}

.pdf-viewer-section {
    flex-basis: 100%;
}

.pdf-viewer-header {
    cursor: pointer;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--accent-color);
    user-select: none;
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
}

.pdf-toggle-icon {
    display: inline-block;
    transition: transform 0.2s ease;
    font-size: 0.75rem;
}

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

.pdf-container-wrapper {
    overflow: hidden;
    height: 0;
    transition: height 0.3s ease-in-out;
}

.paper-item:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.paper-main {
    flex: 1;
    min-width: 0;
}

.paper-header-row {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    margin-bottom: 0.25rem;
    gap: 1rem;
}

.paper-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.3;
}

.venue-badge {
    padding: 0.2rem 0.6rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 600;
    white-space: nowrap;
    border: 1px solid transparent;
}

.venue-badge.default {
    background: #e7f5ff;
    color: #1971c2;
    border-color: #d0ebff;
}

.venue-badge.rejected {
    background: #fff5f5;
    color: #e03131;
    border-color: #ffe3e3;
}

.venue-badge.review {
    background: #fff3bf;
    color: #e67700;
    border-color: #ffec99;
}

.venue-badge.accepted {
    background: #ebfbee;
    color: #2b8a3e;
    border-color: #d3f9d8;
}

.venue-badge.withdrawn {
    background: #f8f9fa;
    color: #868e96;
    border-color: #e9ecef;
}

.paper-authors {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.paper-meta {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.8rem;
    color: var(--text-tertiary);
    flex-wrap: wrap;
}

.meta-item {
    display: inline-flex;
    align-items: center;
}

.meta-separator {
    color: #ced4da;
}

.id-badge {
    font-family: monospace;
    background: var(--bg-color);
    padding: 0.1rem 0.4rem;
    border-radius: 4px;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.paper-actions {
    flex-shrink: 0;
}

/* Loader */
.loader-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 4rem 0;
    color: var(--text-secondary);
}

.spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-color);
    border-radius: 50%;
    border-top-color: var(--accent-color);
    animation: spin 1s linear infinite;
    margin-bottom: 1rem;
}

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

.error-message {
    background: #fff5f5;
    border: 1px solid #ffc9c9;
    color: #e03131;
    padding: 2rem;
    border-radius: 8px;
    text-align: center;
}

@media (max-width: 768px) {
    .dashboard-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .controls-bar {
        flex-direction: column;
        align-items: stretch;
    }

    .btn.primary {
        margin-left: 0;
        justify-content: center;
    }

    #search-input {
        width: 100%;
    }

    .paper-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .paper-actions {
        width: 100%;
    }

    .paper-actions .btn {
        width: 100%;
        justify-content: center;
    }
}