.h22 {
  text-align: center;
}

:root {
    --blue: #e9f3ff;
    --accent: #6aa9ff;
    --light: #e5e7eb;
    --text: #374151;
}

* {
    box-sizing: border-box;
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
}

/* 背景固定于 html */
html {
    background: linear-gradient(180deg, #e9f3ff, #faf8f2) fixed;
    margin: 0;
    padding: 0;
    height: 100%;
}

body {
    display: flex;
    justify-content: center;
    align-items: flex-start;
    min-height: 100%;
    margin: 0;
    padding: 0;
}

.app {
    max-width: 520px;
    width: 100%;
    padding: 20px;          /* 原 body 的 padding 移到这里 */
}

.card {
    background: white;
    padding: 24px;
    border-radius: 16px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.08);
}

h1 {
    text-align: center;
    margin-top: 0;
}

.intro {
    line-height: 1.6;
}

.center {
    text-align: center;
    margin-top: 20px;
}

button {
    border: none;
    padding: 14px 20px;
    border-radius: 10px;
    background: var(--accent);
    color: white;
    font-size: 16px;
    cursor: pointer;
    transition: opacity 0.2s;
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    pointer-events: none;
}

.secondary {
    background: #9ca3af;
}

.secondary:disabled {
    background: #9ca3af;
}

.options {
    margin-top: 20px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.option {
    padding: 12px;
    border: 1px solid var(--light);
    border-radius: 10px;
    cursor: pointer;
    transition: .2s;
}

.option.selected {
    border-color: var(--accent);
    background: #f0f7ff;
}

.progress {
    height: 8px;
    background: #eee;
    border-radius: 10px;
    overflow: hidden;
}

#progressBar {
    height: 100%;
    width: 0%;
    background: var(--accent);
    transition: width .3s;
}

.nav {
    display: flex;
    justify-content: space-between;
    margin-top: 20px;
}

.score {
    font-size: 32px;
    text-align: center;
    color: #2563eb;
    font-weight: bold;
}

.level {
    font-size: 20px;
    text-align: center;
    margin: 10px 0;
}

.report-card {
    background: #f1f7ff;
    padding: 16px;
    border-radius: 10px;
    margin-top: 20px;
}

.analysis {
    background: #f9fafb;
    padding: 14px;
    border-radius: 10px;
    margin-top: 15px;
}

.note {
    font-size: 12px;
    color: #9ca3af;
    margin-top: 30px;
    text-align: center;
}

.hidden {
    display: none;
}

/* 题干序号样式 */
.question-number {
    color: var(--accent);
    font-weight: 600;
    margin-right: 6px;
}