:root {
  --prep-ink: #1d2748;
  --prep-muted: #68728f;
  --prep-faint: #8c96b0;
  --prep-paper: #f5f6fb;
  --prep-panel: #ffffff;
  --prep-line: #e2e6f0;
  --prep-blue: #4963c7;
  --prep-blue-soft: #edf1ff;
  --prep-orange: #e88b62;
  --prep-mint: #4aaf95;
  --prep-plum: #806bb8;
  --prep-shadow: 0 16px 35px rgba(43, 54, 100, .08);
}

* { box-sizing: border-box; }
html { min-height: 100%; scroll-behavior: smooth; background: var(--prep-paper); }
body { margin: 0; min-width: 320px; color: var(--prep-ink); background: var(--prep-paper); font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; letter-spacing: 0; }
button, input { font: inherit; }
button { cursor: pointer; }
a { color: inherit; }
.shell { width: min(1160px, calc(100% - 40px)); margin: 0 auto; }

.topbar { height: 78px; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--prep-line); }
.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--prep-ink); text-decoration: none; }
.mark { width: 34px; height: 34px; position: relative; display: grid; place-items: center; overflow: hidden; border: 1px solid #d8dded; border-radius: 50%; background: #fff; }
.mark:before { content: ""; width: 24px; height: 24px; position: absolute; border: 1px dotted #aab3ce; border-radius: 50%; }
.mark:after { content: ""; width: 2px; height: 28px; position: absolute; border-radius: 9px; background: var(--prep-orange); transform: rotate(35deg); }
.brand-cn { font-size: 18px; font-weight: 750; letter-spacing: .01em; }
.brand-en { display: block; margin-top: 2px; color: var(--prep-muted); font-size: 11px; }
.nav { display: flex; align-items: center; gap: 5px; }
.nav a, .nav button { padding: 10px 12px; border: 0; border-radius: 10px; color: var(--prep-muted); background: transparent; font-size: 13px; text-decoration: none; }
.nav a:hover, .nav button:hover, .nav .active { color: var(--prep-blue); background: var(--prep-blue-soft); }
.icon-btn { width: 35px; height: 35px; display: grid; place-items: center; padding: 0 !important; font-size: 17px !important; }

.prep-hero { padding: 51px 0 36px; border-bottom: 1px solid var(--prep-line); }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1fr) 390px; align-items: end; gap: 55px; }
.eyebrow { color: var(--prep-orange); font-size: 11px; font-weight: 750; letter-spacing: .17em; text-transform: uppercase; }
h1 { max-width: 680px; margin: 10px 0 13px; font-size: clamp(36px, 5vw, 58px); line-height: 1.06; letter-spacing: -.045em; }
.hero-copy p { max-width: 630px; margin: 0; color: var(--prep-muted); font-size: 15px; line-height: 1.85; }
.hero-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-top: 25px; }
.hero-actions a { padding: 10px 14px; border: 1px solid var(--prep-line); border-radius: 10px; color: var(--prep-muted); background: var(--prep-panel); font-size: 12px; text-decoration: none; }
.hero-actions a:first-child { border-color: var(--prep-ink); color: #fff; background: var(--prep-ink); }
.hero-actions a:hover { border-color: #c6d0f7; color: var(--prep-blue); }
.hero-actions a:first-child:hover { border-color: var(--prep-blue); color: #fff; background: var(--prep-blue); }
.hero-note { width: 100%; color: var(--prep-faint); font-size: 11px; }
.prep-map { min-height: 246px; position: relative; overflow: hidden; border: 1px solid var(--prep-line); border-radius: 20px; background: #edf1fb; box-shadow: var(--prep-shadow); }
.prep-map:before { content: ""; width: 190px; height: 190px; position: absolute; left: 36px; top: 34px; border: 1px solid #cbd4f5; border-radius: 50%; box-shadow: 0 0 0 22px rgba(255, 255, 255, .5), 0 0 0 45px rgba(255, 255, 255, .38); }
.prep-map:after { content: ""; width: 340px; height: 1px; position: absolute; left: -25px; top: 122px; background: #d5dcf3; box-shadow: 0 22px 0 #e0e4f5, 0 -22px 0 #e0e4f5; transform: rotate(-31deg); }
.map-label { position: absolute; right: 20px; top: 18px; color: var(--prep-blue); font-size: 10px; font-weight: 750; letter-spacing: .14em; }
.map-pin { width: 13px; height: 13px; position: absolute; z-index: 1; left: 142px; top: 121px; border: 3px solid #fff; border-radius: 50%; background: var(--prep-orange); box-shadow: 0 0 0 5px rgba(232, 139, 98, .17); }
.map-pin.two { left: 254px; top: 69px; background: var(--prep-mint); box-shadow: 0 0 0 5px rgba(74, 175, 149, .15); }
.map-pin.three { left: 282px; top: 166px; background: var(--prep-plum); box-shadow: 0 0 0 5px rgba(128, 107, 184, .15); }
.map-caption { position: absolute; z-index: 1; left: 20px; bottom: 18px; color: var(--prep-ink); font-size: 13px; font-weight: 650; }
.map-caption small { display: block; margin-top: 4px; color: var(--prep-muted); font-size: 11px; font-weight: 400; }

.prep-layout { display: grid; grid-template-columns: 215px minmax(0, 1fr); gap: 30px; padding: 34px 0 80px; }
.side-title { display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; }
.side-title h2 { margin: 0; font-size: 14px; }
.side-title span { color: var(--prep-faint); font-size: 10px; }
.filter-list { display: grid; gap: 5px; position: sticky; top: 20px; }
.filter-btn { width: 100%; display: flex; align-items: center; justify-content: space-between; gap: 8px; padding: 10px 11px; border: 0; border-radius: 9px; color: var(--prep-muted); background: transparent; text-align: left; font-size: 12px; }
.filter-btn:hover, .filter-btn.active { color: var(--prep-blue); background: var(--prep-blue-soft); }
.filter-btn b { color: var(--prep-faint); font-size: 10px; font-weight: 500; }
.side-note { margin: 19px 10px 0 11px; color: var(--prep-faint); font-size: 11px; line-height: 1.65; }

.toolbar { display: flex; align-items: center; gap: 10px; margin-bottom: 18px; }
.search { min-width: 0; flex: 1; height: 47px; display: flex; align-items: center; gap: 10px; padding: 0 14px; border: 1px solid var(--prep-line); border-radius: 11px; background: var(--prep-panel); }
.search-icon { color: var(--prep-faint); font-size: 18px; }
.search input { min-width: 0; flex: 1; border: 0; outline: 0; color: var(--prep-ink); background: transparent; font-size: 13px; }
.search input::placeholder { color: var(--prep-faint); }
.shortcut { color: var(--prep-faint); font-size: 10px; }
.result-count { flex: none; color: var(--prep-faint); font-size: 11px; }
.filter-tabs { display: flex; flex-wrap: wrap; gap: 7px; margin-bottom: 20px; }
.filter-tab { padding: 7px 11px; border: 1px solid var(--prep-line); border-radius: 99px; color: var(--prep-muted); background: var(--prep-panel); font-size: 11px; }
.filter-tab:hover, .filter-tab.active { border-color: #c7d0f4; color: var(--prep-blue); background: var(--prep-blue-soft); }

.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 20px; margin-bottom: 15px; }
.section-heading h2 { margin: 0; font-size: 20px; letter-spacing: -.02em; }
.section-heading p { margin: 0; color: var(--prep-faint); font-size: 12px; }
.section-heading a { color: var(--prep-blue); font-size: 12px; text-decoration: none; }
.companies { scroll-margin-top: 18px; }
.company-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.company-card { --accent: var(--prep-blue); display: flex; min-height: 218px; flex-direction: column; justify-content: space-between; padding: 18px; border: 1px solid var(--prep-line); border-top: 4px solid var(--accent); border-radius: 13px; background: var(--prep-panel); text-decoration: none; transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease; }
.company-card:hover { border-color: #cbd4f4; box-shadow: var(--prep-shadow); transform: translateY(-2px); }
.company-card[data-track="internet"] { --accent: var(--prep-blue); }
.company-card[data-track="platform"] { --accent: var(--prep-orange); }
.company-card[data-track="hardware"] { --accent: var(--prep-mint); }
.company-card[data-track="global"] { --accent: var(--prep-plum); }
.card-meta { display: flex; align-items: center; justify-content: space-between; gap: 10px; color: var(--prep-faint); font-size: 10px; }
.card-tag { color: var(--accent); font-weight: 700; }
.card-number { font-variant-numeric: tabular-nums; }
.company-card h3 { margin: 13px 0 7px; font-size: 18px; }
.company-card p { margin: 0; color: var(--prep-muted); font-size: 12px; line-height: 1.65; }
.card-focus { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 13px; }
.card-focus span { padding: 4px 7px; border-radius: 99px; color: var(--prep-muted); background: #f4f5fa; font-size: 10px; }
.card-footer { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin-top: 19px; padding-top: 11px; border-top: 1px solid var(--prep-line); }
.card-footer small { color: var(--prep-faint); font-size: 10px; }
.card-footer b { color: var(--accent); font-size: 17px; font-weight: 400; }
.card-status { color: var(--prep-faint) !important; font-size: 10px !important; font-weight: 650 !important; }
.empty { display: none; padding: 55px 20px; border: 1px dashed var(--prep-line); border-radius: 13px; color: var(--prep-muted); text-align: center; font-size: 13px; }
.empty.show { display: block; }

.sprint-section { margin-top: 35px; padding: 23px; border: 1px solid #dbe1f4; border-radius: 15px; background: #f0f3ff; }
.sprint-section .section-heading { margin-bottom: 17px; }
.sprint-section .section-heading h2 { font-size: 17px; }
.preview-badge { padding: 5px 8px; border-radius: 99px; color: var(--prep-faint); background: rgba(255, 255, 255, .58); font-size: 10px; }
.sprint-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; }
.sprint-item { min-height: 76px; padding: 11px; border: 1px solid rgba(186, 197, 234, .7); border-radius: 10px; background: rgba(255, 255, 255, .7); }
.sprint-item strong { display: block; color: var(--prep-blue); font-size: 11px; }
.sprint-item span { display: block; margin-top: 6px; color: var(--prep-muted); font-size: 11px; line-height: 1.45; }

.article-page { padding: 39px 0 80px; }
.article-head { max-width: 830px; padding-bottom: 25px; border-bottom: 1px solid var(--prep-line); }
.article-head h1 { max-width: none; margin: 10px 0 12px; font-size: clamp(31px, 4vw, 50px); }
.article-head p { margin: 0; color: var(--prep-muted); font-size: 13px; line-height: 1.75; }
.article-cover { display: block; width: min(100%, 760px); aspect-ratio: 2.5 / 1; height: auto; object-fit: cover; margin: 18px 0 18px; border: 1px solid var(--prep-line); border-radius: 10px; box-shadow: var(--prep-shadow); }
.article-meta { display: flex; flex-wrap: wrap; gap: 8px 17px; margin-top: 17px; color: var(--prep-faint); font-size: 11px; }
.article-layout { display: grid; grid-template-columns: 190px minmax(0, 830px); gap: 34px; padding-top: 28px; }
.article-nav { position: sticky; top: 20px; align-self: start; }
.article-nav h2 { margin: 0 0 10px; font-size: 13px; }
.article-nav a { display: block; padding: 7px 9px; border-radius: 8px; color: var(--prep-muted); font-size: 11px; line-height: 1.45; text-decoration: none; }
.article-nav a:hover { color: var(--prep-blue); background: var(--prep-blue-soft); }
.article-body { min-width: 0; color: var(--prep-ink); font-size: 14px; line-height: 1.85; }
.article-body h2 { margin: 36px 0 12px; padding-left: 12px; border-left: 4px solid var(--prep-blue); font-size: 22px; line-height: 1.35; }
.article-body h3 { margin: 25px 0 9px; color: var(--prep-blue); font-size: 16px; line-height: 1.45; }
.article-body h4 { margin: 22px 0 5px; color: var(--prep-ink); font-size: 15px; line-height: 1.55; }
.article-body p { margin: 11px 0; }
.article-body strong { color: var(--prep-ink); }
.article-body a { color: var(--prep-blue); }
.article-body blockquote { margin: 17px 0; padding: 10px 16px; border-left: 3px solid var(--prep-orange); color: var(--prep-muted); background: #fff7f2; }
.article-body ul, .article-body ol { padding-left: 24px; }
.article-body li { margin: 5px 0; }
.article-body code { padding: 2px 5px; border-radius: 5px; color: #9f5036; background: #fff1e9; font-size: .9em; }
.article-body pre { overflow-x: auto; margin: 16px 0; padding: 15px; border: 1px solid var(--prep-line); border-radius: 10px; background: #f4f6fb; font-size: 12px; line-height: 1.6; }
.article-body pre code { padding: 0; color: var(--prep-ink); background: transparent; }
.article-body table { width: 100%; margin: 17px 0; border-collapse: collapse; font-size: 12px; }
.article-body th, .article-body td { padding: 9px 10px; border: 1px solid var(--prep-line); text-align: left; vertical-align: top; }
.article-body th { color: var(--prep-ink); background: var(--prep-blue-soft); font-weight: 700; }
.article-body tr:nth-child(even) td { background: #fafbfe; }
.article-body hr { margin: 29px 0; border: 0; border-top: 1px solid var(--prep-line); }
.article-back { display: inline-flex; align-items: center; gap: 7px; margin-bottom: 20px; color: var(--prep-blue); font-size: 12px; text-decoration: none; }

.toast { position: fixed; z-index: 20; left: 50%; bottom: 25px; padding: 10px 15px; border-radius: 10px; color: #fff; background: var(--prep-ink); font-size: 12px; opacity: 0; pointer-events: none; transform: translate(-50%, 20px); transition: .25s ease; }
.toast.show { opacity: 1; transform: translate(-50%, 0); }

body.dark { --prep-ink: #f1f3ff; --prep-muted: #a5aecc; --prep-faint: #7c86a8; --prep-paper: #0b1026; --prep-panel: #151d3d; --prep-line: rgba(193, 202, 255, .15); --prep-blue: #aeb8ff; --prep-blue-soft: rgba(151, 159, 240, .14); --prep-orange: #f19a72; --prep-mint: #77d6bd; --prep-plum: #bca8ed; --prep-shadow: 0 16px 35px rgba(0, 0, 0, .16); }
body.dark .mark { border-color: rgba(230, 232, 255, .45); background: #151d3d; }
body.dark .prep-map { background: #141c3c; }
body.dark .prep-map:before { border-color: #48558b; box-shadow: 0 0 0 22px rgba(255, 255, 255, .04), 0 0 0 45px rgba(255, 255, 255, .03); }
body.dark .prep-map:after { background: #34416f; box-shadow: 0 22px 0 #29355f, 0 -22px 0 #29355f; }
body.dark .card-focus span { background: rgba(193, 202, 255, .1); }
body.dark .sprint-section { border-color: rgba(174, 184, 255, .2); background: rgba(58, 71, 135, .35); }
body.dark .sprint-item { border-color: rgba(193, 202, 255, .17); background: rgba(21, 29, 61, .72); }
body.dark .preview-badge { background: rgba(21, 29, 61, .72); }
body.dark .article-body blockquote { background: rgba(241, 154, 114, .1); }
body.dark .article-body pre { background: rgba(21, 29, 61, .78); }
body.dark .article-body th { background: rgba(151, 159, 240, .14); }
body.dark .article-body tr:nth-child(even) td { background: rgba(21, 29, 61, .5); }

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 25px; }
  .prep-map { min-height: 190px; }
  .prep-layout { grid-template-columns: 1fr; gap: 20px; }
  .filter-list { display: flex; overflow-x: auto; position: static; gap: 7px; padding-bottom: 2px; }
  .filter-btn { width: auto; flex: none; white-space: nowrap; }
  .side-note { display: none; }
  .sprint-grid { grid-template-columns: repeat(3, 1fr); }
  .article-layout { grid-template-columns: 1fr; }
  .article-nav { position: static; display: flex; overflow-x: auto; align-items: center; gap: 4px; padding-bottom: 2px; }
  .article-nav h2 { flex: none; margin: 0 7px 0 0; }
  .article-nav a { flex: none; white-space: nowrap; }
}
@media (max-width: 760px) {
  .shell { width: min(100% - 28px, 600px); }
  .topbar { height: 68px; }
  .nav a:not(.active) { display: none; }
  .prep-hero { padding: 31px 0 26px; }
  h1 { font-size: 39px; }
  .hero-copy p { font-size: 14px; }
  .prep-map { min-height: 175px; }
  .prep-map:before { left: 22px; top: 19px; }
  .map-pin { left: 127px; top: 91px; }
  .map-pin.two { left: 233px; top: 51px; }
  .map-pin.three { left: 258px; top: 126px; }
  .toolbar { align-items: stretch; }
  .shortcut { display: none; }
  .company-grid { grid-template-columns: 1fr; }
  .company-card { min-height: 195px; }
  .sprint-section { padding: 17px; }
  .sprint-grid { grid-template-columns: 1fr 1fr; }
  .article-page { padding-top: 28px; }
  .article-head h1 { font-size: 34px; }
  .article-body { font-size: 13px; }
  .article-body table { display: block; overflow-x: auto; white-space: nowrap; }
}