:root {
    --primary: #1677ff;
    --primary-dark: #0958d9;
    --ink: #172033;
    --muted: #5f6b7a;
    --line: #e7edf5;
    --surface: #ffffff;
    --background: #f4f7fb;
    --side-width: 224px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    margin: 0;
    color: var(--ink);
    background: var(--background);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    line-height: 1.8;
}
a { color: var(--primary-dark); text-decoration: none; }
a:hover { text-decoration: underline; }
.guide-header {
    position: sticky;
    top: 0;
    z-index: 20;
    border-bottom: 1px solid rgba(22, 119, 255, .12);
    background: rgba(255, 255, 255, .94);
    backdrop-filter: blur(12px);
}
.guide-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    max-width: 1280px;
    min-height: 68px;
    margin: 0 auto;
    padding: 0 24px;
}
.guide-brand { display: flex; align-items: center; gap: 10px; color: var(--ink); font-weight: 700; }
.guide-brand img { width: 76px; height: auto; display: block; }
.guide-nav { display: flex; flex-wrap: wrap; gap: 22px; font-size: 14px; }
.guide-nav a { color: #344054; }
.guide-layout {
    display: grid;
    grid-template-columns: var(--side-width) minmax(0, 1fr) var(--side-width);
    gap: 24px;
    max-width: 1280px;
    margin: 0 auto;
    padding: 32px 24px 48px;
}
.guide-sidebar {
    position: sticky;
    top: 92px;
    align-self: start;
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 14px;
    background: var(--surface);
    box-shadow: 0 8px 30px rgba(31, 56, 88, .05);
}
.guide-sidebar h2 { margin: 0 0 12px; font-size: 16px; }
.guide-sidebar ul { margin: 0; padding: 0; list-style: none; }
.guide-sidebar li + li { margin-top: 6px; }
.guide-sidebar a { display: block; padding: 7px 9px; border-radius: 7px; color: #475467; font-size: 14px; line-height: 1.45; }
.guide-sidebar a:hover, .guide-sidebar a.active { color: var(--primary-dark); background: #edf5ff; text-decoration: none; }
.guide-article {
    min-width: 0;
    padding: 42px 52px;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: var(--surface);
    box-shadow: 0 12px 40px rgba(31, 56, 88, .07);
}
.breadcrumb { margin: 0 0 18px; color: var(--muted); font-size: 14px; }
.guide-article h1 { margin: 0; color: #101828; font-size: clamp(28px, 4vw, 40px); line-height: 1.28; }
.article-meta { margin: 12px 0 26px; color: #667085; font-size: 14px; }
.article-lead { margin: 0 0 28px; padding: 18px 20px; border-left: 4px solid var(--primary); border-radius: 0 10px 10px 0; background: #f2f7ff; color: #344054; font-size: 17px; }
.guide-article h2 { scroll-margin-top: 90px; margin: 42px 0 14px; color: #101828; font-size: 25px; line-height: 1.4; }
.guide-article h3 { margin: 26px 0 8px; font-size: 19px; }
.guide-article p, .guide-article li { font-size: 16px; }
.guide-article ul, .guide-article ol { padding-left: 24px; }
.guide-article li + li { margin-top: 7px; }
.guide-article table { display: block; width: 100%; margin: 24px 0; overflow-x: auto; border-collapse: collapse; }
.guide-article th, .guide-article td { min-width: 130px; padding: 12px 14px; border: 1px solid var(--line); text-align: left; font-size: 14px; }
.guide-article th { background: #f7f9fc; }
.note, .warning { margin: 22px 0; padding: 15px 18px; border-radius: 10px; }
.note { border: 1px solid #b8d7ff; background: #f2f7ff; }
.warning { border: 1px solid #ffd591; background: #fff7e6; }
.code-line { overflow-x: auto; padding: 14px 16px; border-radius: 9px; background: #101828; color: #e6edf7; font: 14px/1.7 ui-monospace, SFMono-Regular, Menlo, monospace; }
.article-cta { margin-top: 42px; padding: 24px; border-radius: 14px; background: linear-gradient(135deg, #eaf3ff, #f7fbff); }
.article-cta h2 { margin-top: 0; }
.article-cta__links { display: flex; flex-wrap: wrap; gap: 12px; }
.button-link { display: inline-block; padding: 10px 16px; border-radius: 8px; background: var(--primary); color: #fff; font-weight: 600; }
.button-link:hover { background: var(--primary-dark); color: #fff; text-decoration: none; }
.related-list a { border: 1px solid transparent; }
.guide-hub { max-width: 1180px; margin: 0 auto; padding: 56px 24px 72px; }
.guide-hub__hero { max-width: 820px; margin-bottom: 40px; }
.guide-hub__hero h1 { margin: 0 0 14px; font-size: clamp(32px, 5vw, 48px); line-height: 1.2; }
.guide-hub__hero p { color: var(--muted); font-size: 18px; }
.guide-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.guide-card { padding: 24px; border: 1px solid var(--line); border-radius: 14px; background: #fff; box-shadow: 0 8px 28px rgba(31, 56, 88, .05); }
.guide-card h2 { margin: 0 0 10px; font-size: 20px; line-height: 1.45; }
.guide-card p { margin: 0 0 16px; color: var(--muted); font-size: 14px; }
.guide-card__tag { display: inline-block; margin-bottom: 12px; color: var(--primary-dark); font-size: 13px; font-weight: 700; }
.guide-footer { padding: 28px 24px; border-top: 1px solid var(--line); color: #667085; background: #fff; text-align: center; font-size: 13px; }
#backTop { position: fixed; right: 24px; bottom: 24px; display: none; width: 46px; height: 46px; border: 0; border-radius: 50%; color: #fff; background: var(--primary); box-shadow: 0 8px 22px rgba(22, 119, 255, .3); cursor: pointer; font-size: 20px; }
@media (max-width: 1080px) {
    .guide-layout { grid-template-columns: 1fr; }
    .guide-sidebar { position: static; }
    .guide-sidebar.related { order: 3; }
    .guide-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 680px) {
    .guide-header__inner { align-items: flex-start; flex-direction: column; padding-top: 12px; padding-bottom: 12px; }
    .guide-nav { gap: 12px 16px; }
    .guide-layout { padding: 18px 12px 36px; }
    .guide-article { padding: 28px 20px; }
    .guide-grid { grid-template-columns: 1fr; }
}