/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Microsoft YaHei', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #333;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    flex: 1;
}

/* 头部样式 */
header {
    text-align: center;
    margin-bottom: 30px;
}

header h1 {
    color: white;
    font-size: 2.5rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

/* 页面切换 */
.page {
    display: none;
}

.page.active {
    display: block;
}

/* 登录/注册页面样式 */
.login-container {
    background: white;
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    max-width: 400px;
    margin: 0 auto;
}

.login-container h2 {
    text-align: center;
    margin-bottom: 30px;
    color: #333;
    font-size: 1.8rem;
}

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

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

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 2px solid #ddd;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* 按钮样式 */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    cursor: pointer;
    transition: all 0.3s;
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    width: 100%;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

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

.btn-secondary:hover {
    background: #5a6268;
}

.btn-danger {
    background: #dc3545;
    color: white;
}

.btn-danger:hover {
    background: #c82333;
}

/* 注册链接 */
.register-link {
    text-align: center;
    margin-top: 20px;
}

.register-link a {
    color: #667eea;
    text-decoration: none;
}

.register-link a:hover {
    text-decoration: underline;
}

/* 导航栏样式 */
.navbar {
    background: white;
    padding: 20px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    margin-bottom: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.navbar h2 {
    color: #333;
    margin: 0;
}

.nav-buttons {
    display: flex;
    gap: 10px;
}

/* 发布页面样式 */
.post-container {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.user-info {
    background: #f8f9fa;
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 20px;
    font-weight: bold;
    color: #495057;
}

.post-form {
    max-width: 600px;
}

.char-count {
    text-align: right;
    color: #6c757d;
    font-size: 14px;
    margin-top: 5px;
}

.char-count.warning {
    color: #ffc107;
}

.char-count.danger {
    color: #dc3545;
}

/* 记录页面样式 */
.records-container {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.posts-list {
    max-width: 600px;
}

.post-item {
    background: #f8f9fa;
    padding: 20px;
    border-radius: 10px;
    margin-bottom: 20px;
    border-left: 4px solid #667eea;
}

.post-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.post-user {
    font-weight: bold;
    color: #495057;
}

.post-time {
    color: #6c757d;
    font-size: 14px;
}

.post-content {
    color: #333;
    line-height: 1.6;
    margin-bottom: 15px;
}

.post-image {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin-top: 10px;
}

.post-actions {
    display: flex;
    gap: 15px;
}

.post-actions button {
    background: none;
    border: none;
    color: #6c757d;
    cursor: pointer;
    font-size: 14px;
    padding: 5px 10px;
    border-radius: 5px;
    transition: all 0.3s;
}

.post-actions button:hover {
    background: #e9ecef;
    color: #495057;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .login-container {
        padding: 20px;
    }
    
    .navbar {
        flex-direction: column;
        gap: 15px;
    }
    
    .nav-buttons {
        width: 100%;
        justify-content: center;
    }
    
    .post-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 5px;
    }
}

/* 动画效果 */
.page {
    animation: fadeIn 0.5s ease-in;
}

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

/* 成功/错误消息 */
.message {
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 20px;
    text-align: center;
}

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

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

/* 页脚 */
.site-footer {
    background: rgba(255, 255, 255, 0.9);
    color: #333;
    padding: 20px 0;
    margin-top: 40px;
    box-shadow: 0 -5px 15px rgba(0,0,0,0.1);
}

.site-footer .footer-content {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px 20px;
    font-size: 14px;
}

.site-footer .footer-section {
    display: flex;
    align-items: center;
    gap: 4px;
    white-space: nowrap;
}

.site-footer a {
    color: #333;
    text-decoration: none;
}

.site-footer a:hover {
    text-decoration: underline;
}