* {
    box-sizing: border-box;
}
body, html {
    min-height: 100%;
    margin: 0;
    font-family: system-ui, -apple-system, "Microsoft YaHei", Arial, sans-serif;
    overflow-x: hidden;
    background: linear-gradient(135deg, #f8f9fa, #e9ecef);
}

.container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    min-height: 100vh;
    padding: 60px 40px;
    gap: 80px;
}

/* 顶部、底部通栏卡片 */
.full-bar {
    width: 100%;
    max-width: 1140px;
    padding: 32px 40px;
    background-color: #ffffff;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    border-radius: 14px;
    text-align: left;
    line-height: 1.7;
    font-size: 17px;
    color: #222;
}
/* 底部通栏单独样式，加高 */
.full-bar.bottom-bar {
    min-height: 240px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

/* 中间一行容器 */
.mid-row {
    display: flex;
    width: 100%;
    max-width: 1140px;
    gap: 80px;
    align-items: stretch;
}

/* 左侧卡片 */
.content {
    width: 360px;
    flex: none;
    padding: 32px;
    background-color: #ffffff;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    border-radius: 14px;
    text-align: left;
    line-height: 1.7;
    font-size: 17px;
    color: #222;
}

/* 右侧卡片组 */
.square-group {
    display: flex;
    flex-direction: column;
    gap: 80px;
    flex: 1;
}

.square-card {
    flex: 1;
    min-width: 420px;
    padding: 24px;
    background-color: #ffffff;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
    border-radius: 14px;
    text-align: left;
    line-height: 1.7;
    font-size: 17px;
    color: #222;
}

.content h1 {
    font-size: 28px;
    margin: 0 0 16px;
}
.content h2 {
    font-size: 24px;
    margin: 28px 0 12px;
}
.content h3 {
    font-size: 20px;
    margin: 24px 0 10px;
}
.content p {
    margin-bottom: 1em;
}
.content pre {
    background: #f4f5f7;
    padding: 16px;
    border-radius: 8px;
    overflow-x: auto;
}
.content img {
    max-width: 100%;
    border-radius: 8px;
}
.square-card img {
    max-width:100%;
    max-height:100%;
    object-fit: contain;
}

/* ========== 手机端 ========== */
@media screen and (max-width: 820px) {
    .container {
        gap: 40px;
        padding: 32px 0;
    }

    .container > .full-bar,
    .container > .mid-row {
        width: calc(100% - 80px);
        max-width: unset;
        margin: 0 auto;
    }

    .mid-row {
        flex-direction: column;
        gap: 40px;
    }

    .square-group {
        gap: 40px;
    }

    .content {
        width: 100%;
        padding: 32px 28px;
    }

    .square-card {
        width: 100%;
        height: auto;
        min-height: 260px;
        padding: 28px;
    }

    .full-bar {
        padding: 28px;
    }
    /* 手机端同样生效，底部卡片加高、文字垂直居中 */
    .full-bar.bottom-bar {
        min-height: 220px;
        display: flex;
        flex-direction: column;
        justify-content: center;
    }
}

/* 深色模式自动切换 */
@media (prefers-color-scheme: dark) {
    body,html{
        background: linear-gradient(135deg,#222730,#171a20);
    }
    .full-bar,.content,.square-card{
        background:#2c313a;
        color:#e8e8e8;
    }
    .content pre{
        background:#1f2329;
    }
}