/* The media fallback also gives readers the system theme without JavaScript. */
:root {
  color-scheme: light;
  --ink: #242422;
  --muted: #72726d;
  --line: #e6e6e2;
  --paper: #fff;
  --soft: #fafaf8;
  --secondary-ink: #62625c;
  --body-ink: #44443e;
  --control-line: #d8d8d3;
  --card-line: #deded9;
  --focus-line: #888;
  --hover-line: #aaa;
  --shadow: #00000008;
  --hover-shadow: #00000005;
  --focus-shadow: #00000004;
  --button-bg: #252523;
  --button-ink: #fff;
  --button-hover: #454541;
  --error: #ad3028;
  --success: #216c45;
  --logo-filter: none;
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --ink: #f2f2ef;
  --muted: #a7a7a1;
  --line: #343434;
  --paper: #141414;
  --soft: #1c1c1c;
  --secondary-ink: #bababa;
  --body-ink: #d0d0cb;
  --control-line: #4b4b46;
  --card-line: #3d3d38;
  --focus-line: #a5a5a0;
  --hover-line: #6d6d66;
  --shadow: #00000024;
  --hover-shadow: #0000002b;
  --focus-shadow: #ffffff0d;
  --button-bg: #ececea;
  --button-ink: #181818;
  --button-hover: #fff;
  --error: #ffaaa1;
  --success: #8fd6ae;
  --logo-filter: invert(1);
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) {
    color-scheme: dark;
    --ink: #f2f2ef;
    --muted: #a7a7a1;
    --line: #343434;
    --paper: #141414;
    --soft: #1c1c1c;
    --secondary-ink: #bababa;
    --body-ink: #d0d0cb;
    --control-line: #4b4b46;
    --card-line: #3d3d38;
    --focus-line: #a5a5a0;
    --hover-line: #6d6d66;
    --shadow: #00000024;
    --hover-shadow: #0000002b;
    --focus-shadow: #ffffff0d;
    --button-bg: #ececea;
    --button-ink: #181818;
    --button-hover: #fff;
    --error: #ffaaa1;
    --success: #8fd6ae;
    --logo-filter: invert(1);
  }
}
*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.65 Inter,Arial,"PingFang SC","Microsoft YaHei","Noto Sans CJK SC",sans-serif;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}button,input,textarea,select{font:inherit}a:focus-visible,button:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible{outline:2px solid var(--ink);outline-offset:5px}header{height:104px;max-width:1008px;padding:0 24px;margin:auto;display:flex;align-items:center;justify-content:space-between;gap:20px}.brand{display:flex;align-items:center;gap:11px;font-size:26px;font-weight:650;letter-spacing:-.8px}.brand img{width:35px;height:35px;filter:var(--logo-filter)}header nav{display:flex;gap:26px;color:var(--secondary-ink);font-size:14px}header nav a:hover{color:var(--ink)}main{max-width:1008px;padding:0 24px;margin:auto;min-height:65vh}.hero{text-align:center;padding:51px 0 47px}.hero h1{font-size:30px;font-weight:600;line-height:1.45;letter-spacing:-.9px;margin:0 0 28px;text-wrap:balance}.search{display:flex;align-items:center;gap:13px;max-width:640px;margin:0 auto;background:var(--paper);border:1px solid var(--line);border-radius:16px;box-shadow:0 1px 2px var(--shadow);padding:0 18px;height:64px}.search:focus-within{border-color:var(--hover-line);box-shadow:0 0 0 3px var(--focus-shadow)}.search svg{width:23px;height:23px;flex-shrink:0}.search input{border:0;outline:none;background:transparent;width:100%;font-size:16px;color:var(--ink);min-width:0}.search input:focus-visible,textarea:focus-visible{outline:0}.clear{border:0;background:transparent;color:var(--muted);font-size:22px;cursor:pointer;padding:4px 7px;border-radius:7px}.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}.card{display:flex;flex-direction:column;align-items:center;text-align:center;padding:33px 25px 25px;border:1px solid var(--card-line);border-radius:16px;box-shadow:0 1px 2px var(--shadow);min-height:250px;transition:background .16s,border-color .16s,box-shadow .16s}.card:hover{background:var(--soft);border-color:var(--hover-line);box-shadow:0 3px 12px var(--hover-shadow)}.category-icon{width:42px;height:42px;margin:4px 0 23px}.card h2{font-size:17px;font-weight:600;margin:0 0 6px}.card p{color:var(--secondary-ink);font-size:14px;line-height:1.8;margin:0 0 18px}.breadcrumb{display:flex;gap:9px;align-items:center;flex-wrap:wrap;color:var(--muted);font-size:13px;margin:18px 0 34px}.breadcrumb a:hover{text-decoration:underline}.section-head{margin:0 0 30px}.section-head h1{font-size:32px;line-height:1.4;letter-spacing:-.7px;margin:0 0 12px}.section-head p{color:var(--muted);max-width:670px;margin:0}.article-list{border:1px solid var(--line);border-radius:16px;overflow:hidden}.article-row{display:flex;align-items:center;justify-content:space-between;gap:25px;padding:23px 27px;border-bottom:1px solid var(--line)}.article-row:last-child{border-bottom:0}.article-row:hover{background:var(--soft)}.article-row h2{font-size:16px;line-height:1.5;font-weight:550;margin:0 0 5px}.article-row p{font-size:14px;color:var(--muted);margin:0}.arrow{font-size:22px;color:var(--muted)}.article-layout{display:grid;grid-template-columns:minmax(0,680px) 210px;gap:64px}.article-layout article{min-width:0}.article-layout h1{font-size:32px;line-height:1.4;letter-spacing:-.5px;margin:0 0 14px}.intro{color:var(--muted);font-size:16px;line-height:1.8;margin:0 0 38px}.article-layout h2{font-size:21px;line-height:1.5;margin:34px 0 14px;scroll-margin-top:24px}.article-layout p,.article-layout li{color:var(--body-ink);font-size:16px;line-height:1.95}.article-layout ol{padding-left:25px}.article-layout li{padding-left:5px;margin-bottom:10px}.article-layout article a{color:var(--ink);text-decoration:underline;text-underline-offset:4px;overflow-wrap:anywhere}.article-layout aside{align-self:start;position:sticky;top:30px;border-left:1px solid var(--line);padding-left:19px;font-size:13px;color:var(--muted)}aside p{font-weight:600;color:var(--ink)}aside a{display:block;margin:12px 0;line-height:1.7}aside a:hover{color:var(--ink)}.related{margin-top:46px;border-top:1px solid var(--line);padding-top:20px}.related h2{font-size:17px}.related a{display:block;padding:9px 0}.empty{padding:52px 20px;text-align:center;border:1px solid var(--line);border-radius:16px}.empty h2{font-size:20px;font-weight:550}.empty p{color:var(--muted);font-size:14px}.quiet-button{display:inline-block;padding:9px 18px;border:1px solid var(--line);border-radius:9px;background:var(--paper);color:var(--ink);cursor:pointer;margin-top:10px}footer{text-align:center;padding:84px 24px 36px;color:var(--muted);font-size:13px}footer .wordmark{font-size:22px;font-weight:600;letter-spacing:-.6px;opacity:.7;margin-bottom:14px}footer nav{display:flex;gap:20px;justify-content:center}.sr-only{position:absolute;width:1px;height:1px;margin:-1px;overflow:hidden;clip:rect(0,0,0,0)}[hidden]{display:none!important}@media(max-width:700px){header{height:84px;padding:0 20px}.brand{font-size:23px}.brand img{width:30px;height:30px}header nav{gap:14px;font-size:12px}main{padding:0 20px}.hero{padding:32px 0 32px}.hero h1{font-size:25px;line-height:1.55;margin:0 0 23px;letter-spacing:-.6px}.search{height:58px;padding:0 15px}.grid{grid-template-columns:1fr;gap:17px}.card{min-height:219px;padding:28px 25px 23px}.category-icon{margin-bottom:18px}.card p{max-width:270px}.section-head h1,.article-layout h1{font-size:27px}.article-layout{display:block}.article-layout aside{display:none}.article-layout h2{font-size:20px}.breadcrumb{margin-bottom:27px}.article-row{padding:20px}.article-row p{font-size:13px}.article-layout p,.article-layout li{font-size:16px}footer{padding-top:62px}}@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}

.table-scroll{overflow:auto;border:1px solid var(--line);border-radius:12px;margin:24px 0}.table-scroll table{border-collapse:collapse;width:100%;min-width:570px;font-size:14px;line-height:1.65}.table-scroll th,.table-scroll td{text-align:left;vertical-align:top;padding:13px 14px;border-bottom:1px solid var(--line)}.table-scroll th{background:var(--soft);font-weight:600}.table-scroll tr:last-child td{border-bottom:0}.article-meta{font-size:13px;color:var(--muted);margin:-22px 0 28px}.card[data-category="plans-and-billing"]{grid-column:1/-1;display:grid;grid-template-columns:54px 1fr;grid-template-rows:auto auto;min-height:140px;text-align:left;column-gap:23px;padding:28px 32px}.card[data-category="plans-and-billing"] .category-icon{grid-row:1/3;margin:0}.card[data-category="plans-and-billing"] h2{grid-column:2;margin:0}.card[data-category="plans-and-billing"] p{grid-column:2;margin:5px 0 0}.quiet-button:hover{background:var(--soft)}@media(max-width:700px){.card[data-category="plans-and-billing"]{display:flex;align-items:center;text-align:center;min-height:219px;padding:28px 25px 23px}.card[data-category="plans-and-billing"] .category-icon{margin-bottom:18px}.card[data-category="plans-and-billing"] p{margin:6px 0 18px}}

.article-layout .table-hint{display:none}@media(max-width:700px){.article-layout .table-hint{display:block;font-size:12px;color:var(--muted);margin:20px 0 -12px}}
/* Public static pages keep navigation usable before JavaScript loads. */
html{scroll-behavior:smooth}body{overflow-wrap:anywhere}.skip-link{position:absolute;z-index:2;top:12px;left:20px;padding:10px 16px;background:var(--paper);border:1px solid var(--ink);border-radius:8px;transform:translateY(-180%)}.skip-link:focus{transform:translateY(0)}.hero-compact{padding:19px 0 35px}.search-noscript{font-size:13px;color:var(--muted)}.search-message{min-height:170px;text-align:center;color:var(--muted);padding:35px 0}.search-submit:focus-visible{position:static;width:auto;height:auto;margin:0;overflow:visible;clip:auto;padding:4px 10px;white-space:nowrap;border:0;border-radius:6px;background:var(--soft)}.quiet-button+.quiet-button{margin-left:12px}.table-scroll:focus-visible{outline:2px solid var(--ink);outline-offset:4px}.breadcrumb [aria-current="page"]{overflow-wrap:anywhere}.article-layout li:last-child{margin-bottom:0}.article-layout p{margin-top:0}.article-meta time{white-space:nowrap}@media(max-width:700px){.hero-compact{padding:12px 0 25px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

.feedback{margin-top:72px;padding:32px;border:1px solid var(--line);border-radius:18px;background:var(--soft)}.feedback-heading h2{font-size:23px;line-height:1.4;letter-spacing:-.4px;margin:0 0 9px;font-weight:600}.feedback-heading p{margin:0 0 24px;color:var(--muted);font-size:14px}.feedback label{display:flex;flex-direction:column;gap:8px;font-size:14px;font-weight:500}.feedback-fields{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin-bottom:20px}.feedback input,.feedback textarea{width:100%;min-width:0;border:1px solid var(--control-line);border-radius:9px;background:var(--paper);padding:11px 13px;color:var(--ink);font-size:16px;font-weight:400}.feedback textarea{resize:vertical;min-height:140px;line-height:1.65}.feedback input:focus,.feedback textarea:focus{border-color:var(--focus-line)}.feedback-hint{font-size:12px;color:var(--muted);margin:9px 0 20px}.feedback-trap{position:absolute;left:-10000px;top:auto;width:1px;height:1px;overflow:hidden}.feedback-actions{display:flex;align-items:center;gap:22px}.feedback-submit{flex-shrink:0;background:var(--button-bg);color:var(--button-ink);border:1px solid var(--button-bg);border-radius:9px;padding:11px 19px;cursor:pointer;font-size:14px}.feedback-submit:hover{background:var(--button-hover)}.feedback-submit:disabled{cursor:wait;opacity:.6}#feedback-status{font-size:13px;margin:0;color:var(--muted)}#feedback-status[data-state="error"]{color:var(--error)}#feedback-status[data-state="success"]{color:var(--success)}@media(max-width:700px){.feedback{margin-top:44px;padding:23px 20px}.feedback-heading h2{font-size:21px}.feedback-fields{grid-template-columns:1fr;gap:18px;margin-bottom:18px}.feedback-actions{align-items:flex-start;flex-direction:column;gap:14px}.feedback-submit{width:100%}header nav a{white-space:nowrap}.card p{margin-bottom:0}}

.feedback-hint a{text-decoration:underline;text-underline-offset:3px}.feedback-hint a:hover{color:var(--ink)}

/* Keep appearance controls out of the header's single return link. */
.appearance{display:flex;align-items:center;justify-content:center;gap:12px;margin-top:24px;color:var(--muted)}
.appearance select{min-width:112px;min-height:40px;padding:7px 10px;border:1px solid var(--control-line);border-radius:8px;background:var(--paper);color:var(--ink);font-size:13px;cursor:pointer}
.appearance select:hover{border-color:var(--hover-line)}
.search input::placeholder,.feedback input::placeholder,.feedback textarea::placeholder{color:var(--muted);opacity:1}