/* 下载区补充文字 + 安装教程弹层。纯 CSS，无外部依赖。 */
#section-services .dl-lead { color: #9aa4b2; max-width: 760px; margin: 6px auto 0; }
#section-services .platform-desc { display: block; min-height: 52px; margin-bottom: 18px; color: #c4ccd8; }
#section-services .platform-desc span { color: #9aa4b2; font-size: 14px; }
#section-services .dl-status { min-height: 22px; margin: 18px 0 0; text-align: center; color: #c4ccd8; font-size: 14px; }
#section-services .dl-more { margin: 4px 0 0; text-align: center; color: #9aa4b2; font-size: 14px; }
#section-services .dl-more a { color: #c4ccd8; text-decoration: underline; text-underline-offset: 3px; }
#section-services a[aria-disabled="true"], .tut a[aria-disabled="true"] { opacity: .6; pointer-events: none; }

html.tut-open, html.tut-open body { overflow: hidden; }
.tut[hidden], .tut [hidden] { display: none !important; }
.tut {
    position: fixed; inset: 0; z-index: 10000;
    display: flex; align-items: center; justify-content: center;
    padding: 20px; background: rgba(0, 0, 0, .66);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}
.tut, .tut * { box-sizing: border-box; }
.tut-dialog {
    display: flex; flex-direction: column;
    width: 100%; max-width: 760px; max-height: min(88vh, 900px);
    background: #131a26; color: #d7dde6;
    border: 1px solid rgba(255, 255, 255, .1); border-radius: 8px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, .5);
    text-align: left; outline: 0;
}
.tut-head {
    display: flex; align-items: center; gap: 20px; flex: none;
    padding: 0 12px 0 20px; min-height: 56px;
    border-bottom: 1px solid rgba(255, 255, 255, .1);
}
.tut-head h2 { margin: 0; font-size: 17px; line-height: 1.3; font-weight: 700; color: #fff; letter-spacing: 0; }
.tut-tabs { display: flex; gap: 4px; align-self: stretch; margin-right: auto; }
.tut-tabs button {
    appearance: none; border: 0; background: none; cursor: pointer;
    padding: 0 12px; min-height: 56px; font: inherit; font-size: 15px; color: #9aa4b2;
    border-bottom: 2px solid transparent; margin-bottom: -1px;
}
.tut-tabs button:hover { color: #fff; }
.tut-tabs button[aria-selected="true"] { color: #fff; font-weight: 700; border-bottom-color: #1467ff; }
.tut-close {
    appearance: none; flex: none; width: 40px; height: 40px; padding: 0;
    border: 0; border-radius: 6px; background: none; color: #c4ccd8;
    font-size: 26px; line-height: 40px; cursor: pointer;
}
.tut-close:hover { background: rgba(255, 255, 255, .08); color: #fff; }
.tut :focus-visible { outline: 2px solid #6ea3ff; outline-offset: 2px; }

.tut-body { flex: 1 1 auto; min-height: 0; overflow-y: auto; overscroll-behavior: contain; padding: 18px 20px 8px; -webkit-overflow-scrolling: touch; }
.tut-note { margin: 0 0 20px; font-size: 14px; line-height: 1.7; color: #aab3c0; }
.tut-steps { margin: 0; padding: 0; list-style: none; counter-reset: tut; }
.tut-steps > li { counter-increment: tut; margin: 0 0 28px; padding: 0; }
.tut-steps > li > p {
    position: relative; margin: 0 0 12px; padding-left: 34px;
    font-size: 16px; line-height: 1.65; color: #eef2f7;
}
.tut-steps > li > p::before {
    content: counter(tut); position: absolute; left: 0; top: 2px;
    width: 23px; height: 23px; border-radius: 50%;
    background: #1467ff; color: #fff; font-size: 13px; font-weight: 700; line-height: 23px; text-align: center;
}
.tut-steps b { color: #fff; font-weight: 700; }
.tut-figs { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; align-items: start; margin-left: 34px; }
.tut-figs.one { grid-template-columns: minmax(0, 420px); }
.tut-figs.phones.one { grid-template-columns: minmax(0, 220px); }
.tut-figs.mix { grid-template-columns: 220px minmax(0, 336px); }
.tut-figs figure { margin: 0; min-width: 0; }
.tut-figs img { display: block; width: 100%; height: auto; border-radius: 6px; border: 1px solid rgba(255, 255, 255, .12); background: #0c111a; }
.tut-pic { position: relative; display: block; }
.tut-ring { position: absolute; border: 3px solid #ff3b30; border-radius: 6px; pointer-events: none; }
.tut-ring.round { border-radius: 50%; aspect-ratio: 1; }
.tut-ring[data-n]::before {
    content: attr(data-n); position: absolute; left: -6px; top: -6px; width: 22px; height: 22px; border-radius: 50%;
    background: #ff3b30; color: #fff; font: 700 13px/22px "Segoe UI", sans-serif; text-align: center;
}
.tut-figs figcaption { margin-top: 6px; font-size: 12px; line-height: 1.5; color: #8f99a8; }

.tut-foot {
    display: flex; align-items: center; justify-content: flex-end; gap: 10px; flex: none;
    padding: 12px 20px; border-top: 1px solid rgba(255, 255, 255, .1);
}
.tut-status { flex: 1 1 auto; min-width: 0; margin: 0; font-size: 13px; line-height: 1.5; color: #c4ccd8; }
.tut-foot .btn { margin: 0 !important; flex: none; }

@media (max-width: 640px) {
    .tut { padding: 0; align-items: stretch; }
    .tut-dialog { max-width: none; max-height: none; height: 100%; border: 0; border-radius: 0; }
    .tut-head { gap: 8px; padding: 0 6px 0 16px; }
    .tut-head h2 { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
    .tut-tabs button { padding: 0 10px; font-size: 16px; }
    .tut-close { width: 44px; height: 44px; }
    .tut-body { padding: 16px 16px 4px; }
    .tut-steps > li > p { font-size: 15.5px; padding-left: 32px; }
    .tut-figs { margin-left: 0; grid-template-columns: 1fr; }
    .tut-figs.one { grid-template-columns: minmax(0, 1fr); }
    .tut-figs.phones.one, .tut-figs.mix { grid-template-columns: minmax(0, 1fr); }
    .tut-figs.phones.one figure, .tut-figs.mix figure:first-child { max-width: 62%; }
    .tut-foot { flex-wrap: wrap; padding: 10px 16px calc(10px + env(safe-area-inset-bottom)); }
    .tut-status { flex-basis: 100%; }
    .tut-status:empty { display: none; }
    .tut-foot .btn[data-tut-download] { flex: 1 1 auto; }
}
@media (prefers-reduced-motion: no-preference) {
    .tut:not([hidden]) .tut-dialog { animation: tut-in .16s ease-out; }
    @keyframes tut-in { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }
}