/* 全局样式 */
body {
    background-color: #f0f2f5;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 1140px;
    margin: 0 auto;
}

/* 页头样式 */
.page-header {
    text-align: center;
    padding: 30px 0;
    margin-bottom: 20px;
    background: linear-gradient(135deg, #6a11cb 0%, #2575fc 100%);
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

.page-header h1 {
    color: white;
    margin: 0;
    font-size: 2.5rem;
    font-weight: 600;
    text-shadow: 1px 1px 3px rgba(0,0,0,0.2);
    animation: fadeIn 0.8s ease-in-out;
}

/* 公告项样式 */
.announcement-list {
    animation: fadeIn 1s ease-in-out;
}

.announcement-item {
    border-radius: 12px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
    border: none;
    transition: all 0.3s ease;
    overflow: hidden;
    background-color: #fff;
    margin-bottom: 25px;
}

.announcement-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

/* 置顶公告样式 */
.announcement-item:has(.badge.bg-danger) {
    border-left: 5px solid #dc3545;
    background-color: #fff9f9;
}

.badge.bg-danger {
    font-size: 0.8rem;
    padding: 5px 10px;
    border-radius: 30px;
    font-weight: 500;
    animation: pulse 2s infinite;
    background: linear-gradient(45deg, #ff416c, #ff4b2b);
}

/* 公告标题样式 */
.card-title {
    font-size: 1.4rem;
    font-weight: 600;
    color: #2c3e50;
    margin-bottom: 15px;
    border-bottom: 2px solid #f0f0f0;
    padding-bottom: 10px;
}

/* 公告内容样式 */
.announcement-content {
    overflow-wrap: break-word;
    color: #444;
    font-size: 1.05rem;
    line-height: 1.7;
}

/* 公告内容中的图片样式 */
.announcement-content img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin: 15px 0;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

.announcement-content img:hover {
    transform: scale(1.02);
}

/* 公告内容中的视频样式 */
.announcement-content video {
    max-width: 100%;
    border-radius: 8px;
    margin: 15px 0;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
}

/* 附件列表样式 */
.attachments {
    margin-top: 20px;
    background-color: #f8f9fa;
    padding: 15px;
    border-radius: 10px;
    border-left: 4px solid #2575fc;
}

.attachments strong {
    color: #2c3e50;
    font-size: 1.1rem;
}

.attachments .list-group-item {
    background-color: #fff;
    border: 1px solid #e9ecef;
    margin-bottom: 8px;
    border-radius: 8px;
    transition: all 0.2s ease;
}

.attachments .list-group-item:hover {
    background-color: #f0f7ff;
}

.attachments .btn-primary {
    background: linear-gradient(45deg, #2575fc, #6a11cb);
    border: none;
    border-radius: 30px;
    padding: 5px 15px;
    transition: all 0.3s ease;
}

.attachments .btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.15);
}

/* 时间信息样式 */
.text-muted {
    color: #6c757d;
    font-style: italic;
    border-top: 1px solid #f0f0f0;
    padding-top: 10px;
    margin-top: 15px;
}

/* 无公告时的提示 */
.alert-info {
    background: linear-gradient(45deg, #56ccf2, #2f80ed);
    color: white;
    border: none;
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    font-size: 1.2rem;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

/* 动画效果 */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
}

/* 响应式设计优化 */
@media (max-width: 768px) {
    .page-header h1 {
        font-size: 2rem;
    }
    
    .card-title {
        font-size: 1.2rem;
    }
    
    .announcement-content {
        font-size: 1rem;
    }
}

/* 管理员登录按钮样式 */
.btn-outline-secondary {
    border-color: #6c757d;
    color: #6c757d;
}

.btn-outline-secondary:hover {
    background-color: #6c757d;
    color: white;
}