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

body {
    font-family: 'Microsoft YaHei', 'SimHei', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* 标题样式 */
header {
    text-align: center;
    margin-bottom: 30px;
    padding: 20px;
    background-color: #1a73e8;
    color: white;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

h1 {
    font-size: 2.5rem;
    margin-bottom: 20px;
}

h2 {
    font-size: 1.8rem;
    color: #1a73e8;
    border-bottom: 2px solid #1a73e8;
    padding-bottom: 10px;
    margin-bottom: 20px;
}

h3 {
    font-size: 1.4rem;
    color: #333;
    margin-bottom: 15px;
}

/* 学习目标样式 */
.objectives {
    text-align: left;
    background-color: rgba(255, 255, 255, 0.2);
    padding: 15px;
    border-radius: 8px;
    margin-top: 20px;
}

.objectives ol {
    margin-left: 25px;
}

.objectives li {
    margin-bottom: 8px;
}

/* 章节样式 */
.section {
    background-color: white;
    border-radius: 8px;
    padding: 25px;
    margin-bottom: 30px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.content {
    padding: 10px;
}

/* 公式样式 */
.formula {
    font-style: italic;
    font-family: 'Times New Roman', Times, serif;
}

/* 图表容器样式 */
.graph-container {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-bottom: 30px;
}

.graph-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    align-items: center;
    padding: 15px;
    background-color: #f0f7ff;
    border-radius: 8px;
}

.control-group {
    display: flex;
    align-items: center;
    gap: 10px;
}

.graph-wrapper {
    width: 100%;
    height: 400px;
    border: 1px solid #ddd;
    border-radius: 8px;
    overflow: hidden;
}

/* 表格样式 */
.point-table-container {
    margin-top: 20px;
    padding: 15px;
    background-color: #f9f9f9;
    border-radius: 8px;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 20px;
}

th, td {
    padding: 10px;
    text-align: center;
    border: 1px solid #ddd;
}

th {
    background-color: #1a73e8;
    color: white;
}

.input-group {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-top: 15px;
}

input[type="number"], input[type="range"] {
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
}

button {
    padding: 8px 15px;
    background-color: #1a73e8;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #0d62d1;
}

/* 性质卡片样式 */
.properties {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.property-card {
    padding: 15px;
    background-color: #f0f7ff;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

/* 探究活动样式 */
.exploration {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.exploration-controls {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.exploration-graph {
    width: 100%;
    height: 400px;
    border: 1px solid #ddd;
    border-radius: 8px;
    overflow: hidden;
}

.exploration-conclusion {
    padding: 15px;
    background-color: #f0f7ff;
    border-radius: 8px;
}

/* 应用卡片样式 */
.applications {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.application-card {
    padding: 20px;
    background-color: #f0f7ff;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

/* 练习样式 */
.exercises {
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.exercise {
    padding: 20px;
    background-color: #f9f9f9;
    border-radius: 8px;
    border-left: 4px solid #1a73e8;
}

.answer {
    margin-top: 15px;
    padding: 15px;
    background-color: #f0f7ff;
    border-radius: 8px;
    display: none;
}

.answer-table {
    margin: 15px 0;
}

.show-answer-btn {
    margin-top: 10px;
}

/* 总结样式 */
.summary {
    padding: 20px;
    background-color: #f0f7ff;
    border-radius: 8px;
}

.summary ul {
    margin-left: 25px;
    margin-bottom: 20px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .properties, .applications {
        grid-template-columns: 1fr;
    }
    
    .graph-controls {
        flex-direction: column;
        align-items: flex-start;
    }
}