:root {
    --primary-color: #2196F3;
    --success-color: #4CAF50;
    --danger-color: #f44336;
    --bg-color: #f5f7fa;
    --card-bg: #ffffff;
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    margin: 0;
    padding: 0;
    color: #333;
}

/* 关键样式：用于JS控制显示/隐藏 */
.hidden {
    display: none !important;
}

header {
    background-color: var(--primary-color);
    color: white;
    padding: 1rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.header-content {
    max-width: 800px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.container {
    max-width: 800px;
    margin: 20px auto;
    padding: 0 15px;
}

.card {
    background: var(--card-bg);
    border-radius: 10px;
    padding: 30px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    margin-bottom: 20px;
    text-align: center;
}

/* 输入框样式 */
.input-group {
    margin: 20px 0;
}

input#name {
    padding: 10px;
    font-size: 16px;
    border: 2px solid #ddd;
    border-radius: 5px;
    width: 200px;
    text-align: center;
}

/* 按钮样式 */
.btn {
    padding: 12px 30px;
    font-size: 16px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background 0.3s;
}

.primary-btn {
    background-color: var(--primary-color);
    color: white;
}

.primary-btn:hover {
    background-color: #1976D2;
}

.submit-btn {
    background-color: var(--success-color);
    color: white;
    width: 100%;
    margin-top: 20px;
}

.secondary-btn {
    background-color: #607d8b;
    color: white;
}

/* 考试界面样式 */
.exam-header {
    display: flex;
    justify-content: space-between;
    font-weight: bold;
    position: sticky;
    top: 10px;
    z-index: 100;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(5px);
    border: 1px solid #eee;
}

#timer {
    color: var(--danger-color);
    font-size: 1.2em;
}

/* 题目样式 */
.question {
    background: white;
    padding: 20px;
    margin-bottom: 15px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.question-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
    border-bottom: 1px solid #eee;
    padding-bottom: 10px;
}

.skip-button {
    background: #ff9800;
    color: white;
    border: none;
    padding: 5px 10px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 12px;
}

.question-text {
    font-size: 18px;
    font-weight: 500;
    margin-bottom: 15px;
    text-align: left;
}

.options {
    text-align: left;
}

.option {
    margin: 8px 0;
    padding: 10px;
    border: 1px solid #eee;
    border-radius: 5px;
    cursor: pointer;
}

.option:hover {
    background-color: #f0f7ff;
}

/* 结果样式 */
.score-display {
    font-size: 2em;
    font-weight: bold;
    margin: 20px 0;
}

.pass { color: var(--success-color); }
.fail { color: var(--danger-color); }
.exam-count { font-size: 0.5em; color: #666; }

/* 你的 JS 会自动生成 review 样式，这里只需简单的布局 */
.review-section {
    margin-top: 30px;
}