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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background-color: #fff;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    min-height: 100vh;
}

h1 {
    text-align: center;
    color: #2c3e50;
    margin-bottom: 30px;
    padding-bottom: 10px;
    border-bottom: 2px solid #3498db;
}

h2 {
    color: #34495e;
    margin-bottom: 20px;
}

/* 首页菜单样式 */
.menu {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 50px;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 12px 24px;
    text-decoration: none;
    border-radius: 4px;
    font-weight: 600;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background-color: #3498db;
    color: #fff;
}

.btn-primary:hover {
    background-color: #2980b9;
    transform: translateY(-2px);
}

.btn-secondary {
    background-color: #95a5a6;
    color: #fff;
    margin-top: 20px;
}

.btn-secondary:hover {
    background-color: #7f8c8d;
    transform: translateY(-2px);
}

/* 表单样式 */
.message-form {
    max-width: 600px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #555;
}

.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 16px;
    resize: vertical;
    min-height: 120px;
    font-family: inherit;
}

.form-group input[type="file"] {
    display: block;
    margin-bottom: 10px;
}

/* 图片预览样式 */
.image-preview {
    width: 100%;
    min-height: 150px;
    border: 2px dashed #ddd;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    background-color: #fafafa;
}

.image-preview img {
    max-width: 100%;
    max-height: 300px;
    display: block;
}

/* 状态信息样式 */
.status {
    margin-top: 20px;
    padding: 10px;
    border-radius: 4px;
    text-align: center;
    font-weight: 600;
}

.status.success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.status.error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* 返回链接样式 */
.back-link {
    display: inline-block;
    margin-top: 20px;
    color: #3498db;
    text-decoration: none;
    font-weight: 600;
}

.back-link:hover {
    text-decoration: underline;
}

/* 消息列表样式 */
.messages-container {
    margin-top: 30px;
}

.messages-list {
    border: 1px solid #ddd;
    border-radius: 4px;
    padding: 20px;
    min-height: 300px;
    background-color: #fafafa;
}

.message-item {
    background-color: #fff;
    border: 1px solid #eee;
    border-radius: 4px;
    padding: 15px;
    margin-bottom: 15px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
}

.message-item:last-child {
    margin-bottom: 0;
}

.message-text {
    margin-bottom: 10px;
    font-size: 16px;
    line-height: 1.5;
}

.message-image {
    margin-top: 10px;
}

.message-image img {
    max-width: 100%;
    max-height: 300px;
    border-radius: 4px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.message-time {
    font-size: 12px;
    color: #999;
    text-align: right;
    margin-top: 10px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        margin: 0;
        padding: 10px;
        box-shadow: none;
    }
    
    .menu {
        flex-direction: column;
        align-items: center;
    }
    
    .btn {
        width: 200px;
    }
    
    .message-form {
        width: 100%;
    }
}