html,
body {
    min-height: 100%;
    margin: 0;
    background: #fff3f1;
    color: #3b0d08;
    font-family: "Microsoft YaHei", Arial, sans-serif;
    -webkit-user-select: none;
    -moz-user-select: none;
    user-select: none;
}

.viewer-shell {
    min-height: 100vh;
    padding: 14px 12px 24px;
    box-sizing: border-box;
}

.viewer-tip {
    position: sticky;
    top: 0;
    z-index: 2;
    width: fit-content;
    margin: 0 auto 12px;
    border-radius: 15px;
    background: rgba(186, 42, 23, .94);
    color: #fff;
    padding: 5px 16px;
    font-size: 13px;
    line-height: 20px;
    box-shadow: 0 4px 12px rgba(165, 25, 7, .18);
}

.viewer-pages {
    max-width: 1180px;
    margin: 0 auto;
}

.viewer-page {
    margin: 0 auto 18px;
    text-align: center;
}

.viewer-page-inner {
    position: relative;
    width: 100%;
    /* 未渲染时用 padding-top 撑出比例占位，渲染后清空并放入 canvas。 */
    height: 0;
}

.viewer-page-placeholder .viewer-page-inner {
    background: #fff;
    border-radius: 4px;
    box-shadow: 0 8px 24px rgba(165, 25, 7, .10);
}

.viewer-page canvas {
    position: absolute;
    top: 0;
    left: 0;
    display: block;
    /* 宽度铺满占位框、高度按画布固有比例自适应，与 padding-top 占位高度贴合，
       渲染/回收切换时页高度恒定，滚动不再错位。 */
    width: 100%;
    height: auto !important;
    border-radius: 4px;
    background: #fff;
    box-shadow: 0 8px 24px rgba(165, 25, 7, .14);
    pointer-events: none;
}

.viewer-loading,
.viewer-error {
    margin: 70px auto;
    border-radius: 10px;
    background: #fff;
    padding: 28px 20px;
    text-align: center;
    box-shadow: 0 8px 24px rgba(165, 25, 7, .12);
}

.viewer-error {
    color: #b42318;
}

@media print {
    body {
        display: none !important;
    }
}

@media (max-width: 768px) {
    .viewer-shell {
        padding: 10px 6px 18px;
    }

    .viewer-page {
        margin-bottom: 12px;
    }
}