/* 橙色主题基础样式 */
:root {
    --primary-orange: #FFA500;
    --light-orange: #FFB84D;
    --dark-orange: #CC7A00;
    --border-gray: #ccc;
    --light-gray: #f0f0f0;
    --dark-gray: #333;
    --white: #fff;
}

body {
    font-family: 'Arial', sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--light-gray);
    color: var(--dark-gray);
}

/* 导航栏样式 */
.navbar {
    background-color: var(--primary-orange);
    padding: 15px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.navbar ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
    text-align: center;
}

.navbar li {
    display: inline-block;
    margin: 0 15px;
}

.navbar a {
    color: white;
    text-decoration: none;
    font-weight: bold;
    padding: 10px 15px;
    border-radius: 5px;
    transition: background-color 0.3s;
}

.navbar a:hover {
    background-color: var(--dark-orange);
}

/* 主要内容区样式 */
main {
    padding: 20px;
    max-width: 1200px;
    margin: 0 auto;
}

/* 新闻和趣事项目样式 */
.news-item, .fun-item {
    background-color: white;
    margin: 15px 0;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.news-item h3, .fun-item h3 {
    margin-top: 0;
    color: var(--dark-orange);
}

.news-date, .fun-date {
    color: #666;
    font-size: 0.9em;
    margin: 10px 0;
}

.news-content, .fun-content {
    line-height: 1.6;
}

.item-separator {
    height: 1px;
    background-color: var(--border-gray);
    margin: 15px 0;
}

/* 作业页面样式 */
.subject-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.subject-box {
    background-color: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    text-align: center;
    height: 150px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

/* 答案页面样式 */
.download-link {
    display: inline-block;
    background-color: var(--primary-orange);
    color: white;
    padding: 12px 24px;
    text-decoration: none;
    border-radius: 5px;
    font-weight: bold;
    margin-top: 20px;
    transition: background-color 0.3s;
}

.download-link:hover {
    background-color: var(--dark-orange);
}

/* 聊天页面样式 */
.chat-container {
    display: flex;
    height: 80vh;
    background-color: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.chat-sidebar {
    width: 300px;
    background-color: #222;
    color: white;
    padding: 20px 10px;
    overflow-y: auto;
}

.chat-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    border-left: 1px solid var(--border-gray);
}

.chat-messages {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
    background-color: #f5f5f5;
}

.chat-input {
    padding: 15px;
    border-top: 1px solid var(--border-gray);
    background-color: white;
}

.chat-input input {
    width: calc(100% - 20px);
    padding: 10px;
    border: 1px solid var(--border-gray);
    border-radius: 5px;
    margin-bottom: 10px;
}

.chat-input button {
    background-color: var(--primary-orange);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
}

/* 登录/注册表单样式 */
.form-container {
    max-width: 400px;
    margin: 50px auto;
    padding: 30px;
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

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

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

.form-group input {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-gray);
    border-radius: 5px;
    box-sizing: border-box;
}

.btn {
    background-color: var(--primary-orange);
    color: white;
    border: none;
    padding: 12px 20px;
    border-radius: 5px;
    cursor: pointer;
    width: 100%;
    font-size: 16px;
}

.btn:hover {
    background-color: var(--dark-orange);
}