:root {
    --primary-color: #6c5ce7;
    --secondary-color: #a29bfe;
    --bg-color: #f5f6fa;
    --text-color: #2d3436;
    --card-bg: #ffffff;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --border-radius: 12px;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Navbar */
.navbar {
    background: var(--card-bg);
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

.nav-links {
    display: flex;
    gap: 20px;
    align-items: center;
}

.nav-item {
    cursor: pointer;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-item:hover {
    color: var(--primary-color);
}

.btn {
    padding: 8px 16px;
    border-radius: 20px;
    border: none;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s;
}

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

.btn-primary:hover {
    background: #5b4cc4;
    transform: translateY(-2px);
}

.search-bar {
    display: flex;
    background: #f1f2f6;
    padding: 5px 15px;
    border-radius: 20px;
    width: 300px;
}

.search-bar input {
    border: none;
    background: transparent;
    outline: none;
    width: 100%;
    margin-left: 10px;
}

/* Layout */
.container {
    max-width: 1200px;
    margin: 20px auto;
    display: grid;
    grid-template-columns: 250px 1fr 300px;
    gap: 20px;
    padding: 0 15px;
}

.container.home-layout {
    grid-template-columns: 250px 1fr 300px;
}

/* Search Page Styles */
.search-page-container {
    max-width: 800px;
    margin: 20px auto;
    padding: 0 15px;
}

.large-search-bar {
    display: flex;
    gap: 10px;
    margin-top: 10px;
}

.large-search-bar input {
    flex: 1;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 8px;
    font-size: 1rem;
}

.search-results {
    margin-top: 20px;
}

/* Sidebars */
.sidebar {
    position: sticky;
    top: 90px;
    height: fit-content;
}

.card {
    background: var(--card-bg);
    padding: 20px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    margin-bottom: 20px;
}

.sidebar-title {
    font-size: 1.1rem;
    font-weight: bold;
    margin-bottom: 15px;
    color: var(--primary-color);
    border-bottom: 2px solid var(--bg-color);
    padding-bottom: 10px;
}

/* Notifications styling */
.notifications-container {
    max-height: 100%;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

/* Removed empty ruleset */

.notifications-container.expanded {
    max-height: 500px;
    overflow-y: auto;
}

.notification-item {
    padding: 10px;
    border-bottom: 1px solid #eee;
    transition: opacity 0.3s ease, max-height 0.3s ease;
}

.hidden-notification {
    display: none;
    opacity: 0;
    max-height: 0;
    padding: 0 10px;
    border-bottom: none;
}

.visible-notification {
    display: block;
    opacity: 1;
    max-height: 100px;
    padding: 10px;
    border-bottom: 1px solid #eee;
}

.view-more-btn {
    width: 100%;
    padding: 10px;
    text-align: center;
    color: var(--primary-color);
    cursor: pointer;
    font-size: 0.9rem;
    transition: background-color 0.3s ease;
    border-radius: 4px;
    margin-top: 10px;
}

.view-more-btn:hover {
    background-color: #f0f0f0;
}

.expand-icon {
    font-size: 0.7rem;
    margin-left: 5px;
    transition: transform 0.3s ease;
}

.popular-item {
    margin-bottom: 10px;
    padding-bottom: 10px;
    border-bottom: 1px solid #f0f0f0;
}

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

.popular-title {
    font-weight: 600;
    font-size: 0.95rem;
}

.popular-meta {
    font-size: 0.8rem;
    color: #888;
}

/* Feed */
.create-post-box {
    margin-bottom: 20px;
}

.create-post-box textarea {
    width: 100%;
    border: none;
    border-radius: 8px;
    padding: 15px;
    resize: none;
    height: 100px;
    margin-bottom: 15px;
    background: #f8f9fa;
    font-size: 1rem;
    outline: none;
}

.create-post-box textarea:focus {
    background: #fff;
    box-shadow: inset 0 0 0 1px var(--primary-color);
}

#image-preview-container {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 20px;
}

.preview-item {
    position: relative;
    width: 80px;
    height: 80px;
}

.preview-thumbnail {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 8px;
}

.preview-remove {
    position: absolute;
    top: -5px;
    right: -5px;
    background: rgba(0,0,0,0.6);
    color: white;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    cursor: pointer;
    transition: background 0.2s;
}

.preview-remove:hover {
    background: #e74c3c;
}

.upload-trigger {
    width: 80px;
    height: 80px;
    border: 2px dashed #ddd;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
    color: #aaa;
    font-size: 2rem;
    font-weight: 300;
}

.upload-trigger:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    background: #f0f0ff;
}

.create-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.memoir-post {
    margin-bottom: 20px;
}

.post-header {
    display: flex;
    align-items: center;
    margin-bottom: 15px;
}

.avatar-placeholder {
    width: 40px;
    height: 40px;
    background: var(--secondary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: bold;
    margin-right: 0; /* Remove default margin as it's handled by flex gap or specific styles */
}

.user-avatar-img {
    border-radius: 50%;
    object-fit: cover;
    background: var(--bg-color);
    border: 1px solid #eee;
}

.post-info h4 {
    font-size: 1rem;
}

.post-info span {
    font-size: 0.8rem;
    color: #888;
}

.post-content {
    margin-bottom: 15px;
    white-space: pre-wrap;
}

.post-images {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 10px;
    margin-bottom: 15px;
}

.post-images img {
    width: 100%;
    height: 150px;
    object-fit: cover;
    border-radius: 8px;
    cursor: pointer;
    transition: transform 0.2s;
}

.post-images img:hover {
    transform: scale(1.02);
}

.post-actions {
    display: flex;
    gap: 20px;
    border-top: 1px solid #f0f0f0;
    padding-top: 15px;
}

.action-btn {
    display: flex;
    align-items: center;
    gap: 5px;
    cursor: pointer;
    color: #666;
    transition: color 0.2s;
}

.action-btn:hover, .action-btn.active {
    color: var(--primary-color);
}

/* Comments Section */
.comments-section {
    margin-top: 15px;
    background: #f9f9f9;
    padding: 10px;
    border-radius: 8px;
    display: none;
}

.comments-section.show {
    display: block;
}

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    gap: 5px;
    margin: 20px 0;
}

.page-btn {
    padding: 8px 12px;
    border: 1px solid #ddd;
    background: white;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s;
    color: var(--text-color);
}

.page-btn:hover:not(:disabled) {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.page-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.page-btn:disabled {
    background: #f9f9f9;
    color: #ccc;
    cursor: not-allowed;
}

.comment {
    display: flex;
    gap: 10px;
    margin-bottom: 10px;
    border-bottom: 1px solid #eee;
    padding-bottom: 5px;
}

.comment-content {
    flex: 1;
}

.comment-author {
    font-weight: 600;
    font-size: 0.9rem;
}

.comment-text {
    font-size: 0.9rem;
}

/* Forms (Login/Register) */
.auth-container {
    max-width: 400px;
    margin: 50px auto;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

/* Notifications List Page */
.notifications-list-container {
    max-width: 800px;
    margin: 20px auto;
    padding: 0 15px;
}

.notifications-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

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

.notification-list-item {
    background: var(--card-bg);
    padding: 15px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    margin-bottom: 15px;
    transition: transform 0.2s, box-shadow 0.2s;
}

.notification-list-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0,0,0,0.1);
}

.notification-list-item .notification-content {
    font-size: 0.95rem;
    margin-bottom: 5px;
}

.notification-list-item .notification-time {
    font-size: 0.8rem;
    color: #888;
}

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    gap: 5px;
    margin: 20px 0;
}

.page-btn {
    padding: 8px 12px;
    border: 1px solid #ddd;
    background: white;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s;
    color: var(--text-color);
}

.page-btn:hover:not(:disabled) {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.page-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.page-btn:disabled {
    background: #f9f9f9;
    color: #ccc;
    cursor: not-allowed;
}

.form-group input {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 6px;
}

.auth-links {
    margin-top: 15px;
    font-size: 0.9rem;
    text-align: center;
}

.auth-links a {
    color: var(--primary-color);
}

/* Admin */
.admin-table {
    width: 100%;
    border-collapse: collapse;
}

.admin-table th, .admin-table td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

.delete-btn {
    color: red;
    cursor: pointer;
}

/* Responsive */
@media (max-width: 900px) {
    .container, .container.home-layout {
        grid-template-columns: 1fr;
    }
    
    /* 让侧边栏在小屏幕上显示在主内容下方，而不是隐藏 */
    .sidebar {
        display: block; 
        position: static;
        width: 100%;
        margin-bottom: 20px;
    }
    
    /* 调整导航栏，使其在小屏幕上更紧凑 */
    .navbar {
        padding: 10px 15px;
        flex-direction: column;
        gap: 10px;
    }
    
    .search-bar {
        width: 100%;
    }
    
    .nav-links {
        width: 100%;
        justify-content: center;
        flex-wrap: wrap;
    }
}

/* Modal */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 2000;
    display: none;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: var(--card-bg);
    width: 90%;
    max-width: 600px;
    border-radius: var(--border-radius);
    padding: 20px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    position: relative;
    animation: modalSlideIn 0.3s ease-out;
}

#post-form textarea {
    width: 100%;
    border: none;
    border-radius: 8px;
    padding: 15px;
    resize: none;
    height: 120px;
    margin-bottom: 15px;
    background: #f8f9fa;
    font-size: 1rem;
    outline: none;
}

#post-form textarea:focus {
    background: #fff;
    box-shadow: inset 0 0 0 1px var(--primary-color);
}

@keyframes modalSlideIn {
    from {
        transform: translateY(-20px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.modal-close {
    position: absolute;
    top: 15px;
    right: 20px;
    font-size: 1.5rem;
    cursor: pointer;
    color: #888;
}

.modal-close:hover {
    color: var(--text-color);
}

/* Notifications List Page Styles */
#notifications-list {
    margin-bottom: 20px;
}

#notifications-list .notification-item {
    padding: 15px;
    border-bottom: 1px solid #eee;
    margin-bottom: 10px;
    border-radius: 8px;
    transition: background-color 0.3s ease;
}

#notifications-list .notification-item:hover {
    background-color: #f9f9f9;
}

#notifications-list .notification-item:last-child {
    margin-bottom: 0;
    border-bottom: none;
}

#notifications-pagination {
    display: flex;
    justify-content: center;
    gap: 5px;
    margin-top: 20px;
}

.more-notifications {
    text-align: center;
    padding: 10px;
    color: var(--primary-color);
    font-size: 0.85rem;
    cursor: pointer;
    transition: color 0.3s ease;
}

.more-notifications:hover {
    color: #5b4cc4;
}