:root {
  --blue: #1f6fe5;
  --blue-dark: #0b58c8;
  --blue-soft: #f4f8ff;
  --ink: #17263b;
  --muted: #7f8b9d;
  --line: #e3eaf3;
  --green: #25c28a;
  --shadow: 0 18px 50px rgba(38, 87, 142, .10);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: #fff; font-family: "Segoe UI", "Microsoft YaHei", sans-serif; }
button, input, select { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; text-decoration: none; }

.site-header { position: sticky; top: 0; z-index: 20; height: 64px; display: flex; align-items: center; gap: 30px; padding: 0 40px; background: rgba(255, 255, 255, .96); border-bottom: 1px solid #e7edf5; backdrop-filter: blur(14px); }
.brand { display: flex; align-items: center; gap: 10px; min-width: 190px; }
.brand-mark { display: grid; place-items: center; width: 34px; height: 34px; border-radius: 9px; color: #fff; background: var(--blue); font-size: 20px; font-weight: 800; }
.brand strong, .brand small { display: block; }
.brand strong { font-size: 16px; letter-spacing: .04em; }
.brand small { margin-top: 2px; color: #9aa6b7; font-size: 10px; }
.main-nav { display: flex; align-self: stretch; gap: 4px; }
.nav-link { display: grid; place-items: center; padding: 0 17px; color: #687486; font-size: 14px; transition: .2s ease; border-bottom: 2px solid transparent; }
.nav-link:hover, .nav-link.is-active { color: var(--blue); border-bottom-color: var(--blue); background: #f8fbff; }
.account-button { margin-left: auto; }
.outline-button, .mini-button { border: 1px solid #ccd8e6; color: #506074; background: #fff; cursor: pointer; transition: .2s ease; }
.outline-button { height: 34px; padding: 0 16px; font-size: 13px; }
.outline-button:hover, .mini-button:hover { border-color: var(--blue); color: var(--blue); }

.hero { position: relative; display: grid; grid-template-columns: minmax(0, 1.18fr) minmax(420px, .82fr); min-height: 625px; overflow: hidden; background: #fff; }
.hero-blue { position: relative; background: linear-gradient(145deg, #2474e8 0%, #1a67d8 70%, #155fd0 100%); clip-path: polygon(0 0, 100% 0, 72% 100%, 0 100%); }
.hero-copy { width: 100%; max-width: 820px; padding: 128px clamp(44px, 7vw, 118px) 80px clamp(28px, 5vw, 80px); color: #fff; }
.eyebrow { margin: 0 0 14px; color: #78a6e7; font-size: 12px; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; }
.eyebrow.light { color: rgba(255,255,255,.84); }
.eyebrow span { display: inline-block; width: 22px; height: 2px; margin: 0 8px 3px 0; background: currentColor; }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 18px; font-size: clamp(52px, 6vw, 84px); line-height: .98; letter-spacing: -.06em; }
.hero-lead { max-width: 640px; margin-bottom: 24px; font-size: clamp(23px, 2.4vw, 34px); line-height: 1.25; letter-spacing: -.04em; }
.hero-description { max-width: 548px; margin-bottom: 31px; color: rgba(255,255,255,.83); font-size: 15px; line-height: 2; }
.hero-actions { display: flex; gap: 12px; margin-bottom: 40px; }
.button { display: inline-flex; align-items: center; justify-content: center; gap: 10px; min-height: 44px; padding: 0 22px; border: 1px solid transparent; cursor: pointer; font-size: 14px; font-weight: 700; transition: .2s ease; }
.button:hover { transform: translateY(-1px); box-shadow: 0 10px 22px rgba(27, 91, 183, .18); }
.button-light { color: var(--blue); background: #fff; }
.button-ghost { color: #fff; border-color: rgba(255,255,255,.54); background: transparent; }
.button-primary { color: #fff; background: var(--blue); }
.hero-stats { display: grid; grid-template-columns: repeat(3, minmax(110px, 1fr)); max-width: 520px; }
.hero-stats > div { padding-right: 25px; border-right: 1px solid rgba(255,255,255,.28); }
.hero-stats > div + div { padding-left: 25px; }
.hero-stats > div:last-child { border-right: 0; }
.hero-stats strong, .hero-stats span { display: block; }
.hero-stats strong { margin-bottom: 7px; font-size: 14px; }
.hero-stats span { color: rgba(255,255,255,.74); font-size: 12px; }
.hero-art { position: relative; display: grid; place-items: center; min-height: 625px; overflow: hidden; background: radial-gradient(circle at 50% 45%, #fff 0, #fbfdff 42%, #f3f7fd 100%); }
.glow { position: absolute; border: 1px solid rgba(42, 126, 234, .15); border-radius: 50%; }
.glow-one { width: 430px; height: 430px; }
.glow-two { width: 600px; height: 600px; border-color: rgba(42, 126, 234, .08); }
.shield { position: relative; display: grid; place-items: center; width: 260px; height: 310px; clip-path: polygon(50% 0, 95% 17%, 88% 68%, 50% 100%, 12% 68%, 5% 17%); background: linear-gradient(145deg, #0f69df 5%, #7bc8fb 55%, #1b79e8 100%); filter: drop-shadow(0 30px 24px rgba(25, 106, 210, .24)); transform: rotate(2deg); }
.shield::after { content: ""; position: absolute; inset: 10px; clip-path: inherit; background: linear-gradient(145deg, #fff 0%, #eaf7ff 100%); }
.shield-inner { position: relative; z-index: 1; display: grid; place-items: center; width: 172px; height: 202px; clip-path: polygon(50% 0, 94% 17%, 86% 68%, 50% 100%, 14% 68%, 6% 17%); border: 1px solid rgba(72, 177, 250, .66); background: rgba(255,255,255,.66); color: var(--blue); transform: rotate(-2deg); }
.shield-inner strong { font-size: 36px; letter-spacing: -.06em; }
.shield-inner small { margin-top: -22px; color: #7ea4d1; font-size: 8px; letter-spacing: .18em; }
.chip { position: absolute; top: 49px; display: grid; grid-template-columns: repeat(2, 7px); gap: 4px; padding: 9px; border: 1px solid #8ed7ff; background: #e9f8ff; box-shadow: inset 0 0 0 4px #fff; }
.chip span { width: 7px; height: 7px; background: #54c8e3; }
.art-label { position: absolute; padding: 8px 11px; border: 1px solid #dce9f8; background: rgba(255,255,255,.88); box-shadow: 0 12px 25px rgba(62, 130, 208, .12); color: #7191b4; font-size: 12px; }
.label-top { top: 27%; left: 27%; }
.label-right { top: 35%; right: 13%; }
.label-bottom { bottom: 29%; right: 27%; }
.label-left { bottom: 35%; left: 13%; }

.section-tabs { position: relative; z-index: 5; display: grid; grid-template-columns: repeat(4, 1fr); max-width: 1160px; margin: -20px auto 0; box-shadow: var(--shadow); background: rgba(255,255,255,.94); }
.tab { padding: 19px 12px; border-bottom: 3px solid transparent; color: #a4afbe; text-align: center; font-size: 14px; }
.tab:hover, .tab.is-selected { border-bottom-color: var(--blue); color: var(--blue); background: #f9fbff; }
.content-section { width: min(1160px, calc(100% - 64px)); margin: 0 auto; padding: 104px 0; }
.section-heading { display: flex; justify-content: space-between; gap: 60px; align-items: end; margin-bottom: 48px; }
.section-heading h2 { max-width: 630px; margin-bottom: 0; font-size: clamp(30px, 3.5vw, 44px); line-height: 1.2; letter-spacing: -.05em; }
.section-heading > p { max-width: 390px; margin-bottom: 5px; color: var(--muted); font-size: 14px; line-height: 1.9; }
.feature-list { border-top: 1px solid var(--line); }
.feature-row { display: grid; grid-template-columns: 110px 1fr; gap: 26px; min-height: 150px; padding: 36px 24px; border-bottom: 1px solid var(--line); transition: .2s ease; }
.feature-row:hover { background: #fbfdff; }
.feature-index { color: #96b9e9; font-size: 14px; font-weight: 700; letter-spacing: .08em; }
.feature-row h3 { margin-bottom: 12px; font-size: 20px; }
.feature-row p { max-width: 680px; margin-bottom: 0; color: var(--muted); line-height: 1.8; }
.band { background: var(--blue-soft); }
.band-blue { background: #f4f8ff; border-top: 1px solid #e7eff9; border-bottom: 1px solid #e7eff9; }
.advantage-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 36px 56px; }
.advantage-item { padding-top: 6px; }
.mini-icon { display: grid; place-items: center; width: 38px; height: 38px; margin-bottom: 22px; border: 1px solid #bddcff; color: var(--blue); background: #fff; font-size: 13px; }
.advantage-item h3 { margin-bottom: 10px; font-size: 18px; }
.advantage-item p { margin-bottom: 0; color: var(--muted); line-height: 1.8; font-size: 14px; }
.scenario-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.scenario-card { min-height: 245px; padding: 30px; border: 1px solid var(--line); border-top: 3px solid #dce6f2; transition: .2s ease; }
.scenario-card.is-active, .scenario-card:hover { border-top-color: var(--blue); box-shadow: var(--shadow); transform: translateY(-3px); }
.scenario-card span, .plan-card > span { color: #84a9db; font-size: 12px; font-weight: 700; letter-spacing: .08em; }
.scenario-card h3 { margin: 33px 0 14px; font-size: 21px; }
.scenario-card p { margin-bottom: 0; color: var(--muted); font-size: 14px; line-height: 1.8; }
.architecture-band { background: #f6f9fe; }
.architecture-visual { display: flex; align-items: center; justify-content: center; gap: 0; padding: 65px 30px; border: 1px solid #e0ebfa; background: linear-gradient(135deg, #fff, #f5faff); }
.flow-node { min-width: 160px; padding: 18px 16px; border: 1px solid #c9e0fb; background: #fff; text-align: center; box-shadow: 0 9px 25px rgba(75, 136, 209, .08); }
.flow-node span, .flow-node small { display: block; }
.flow-node span { margin-bottom: 6px; color: var(--blue); font-weight: 700; }
.flow-node small { color: var(--muted); font-size: 11px; line-height: 1.5; }
.flow-sdk { border-color: #79b9f1; background: #eaf5ff; }
.flow-node-main { border-color: #89dfc5; background: #edfff8; }
.flow-node-main span { color: #1a9d76; }
.flow-line { width: 50px; height: 1px; background: #9fc8ec; }

.config-section { padding-top: 112px; }
.config-heading { margin-bottom: 34px; }
.config-layout { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(360px, .9fr); gap: 20px; align-items: start; }
.config-form, .config-preview { border: 1px solid var(--line); background: #fff; box-shadow: var(--shadow); }
.config-form { padding: 30px; }
.form-block { padding: 0 0 30px; margin-bottom: 28px; border-bottom: 1px solid var(--line); }
.form-block:last-of-type { margin-bottom: 20px; }
.form-block-title { display: flex; gap: 14px; align-items: start; margin-bottom: 22px; }
.form-block-title > span { color: var(--blue); font-size: 12px; font-weight: 800; letter-spacing: .1em; }
.form-block-title strong, .form-block-title small { display: block; }
.form-block-title strong { margin-bottom: 5px; font-size: 17px; }
.form-block-title small { color: var(--muted); font-size: 12px; }
label { display: block; color: #59697e; font-size: 12px; font-weight: 700; }
input, select { width: 100%; height: 42px; margin-top: 9px; padding: 0 12px; border: 1px solid #d9e3ef; outline: 0; color: var(--ink); background: #fbfdff; }
input:focus, select:focus { border-color: #77ace9; box-shadow: 0 0 0 3px rgba(31,111,229,.08); }
.form-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 15px; margin-top: 15px; }
.contact-field { margin-top: 15px; }
.platform-options { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.select-tile { min-height: 104px; padding: 14px 11px; border: 1px solid #dce6f1; background: #fff; color: #718097; cursor: pointer; text-align: left; transition: .2s ease; }
.select-tile b, .select-tile span, .select-tile small { display: block; }
.select-tile b { margin-bottom: 12px; color: #9cb5d2; font-size: 17px; }
.select-tile span { margin-bottom: 4px; color: var(--ink); font-size: 13px; font-weight: 700; }
.select-tile small { color: var(--muted); font-size: 11px; }
.select-tile.is-selected { border-color: var(--blue); background: #f2f8ff; box-shadow: inset 0 0 0 1px var(--blue); }
.select-tile.is-selected b { color: var(--blue); }
.switch-row { display: flex; justify-content: space-between; gap: 20px; align-items: center; padding: 14px 0; border-top: 1px solid #edf1f6; font-weight: 400; }
.switch-row:first-of-type { border-top: 0; }
.switch-row strong, .switch-row small { display: block; }
.switch-row strong { margin-bottom: 4px; color: var(--ink); font-size: 13px; }
.switch-row small { color: var(--muted); font-size: 11px; font-weight: 400; }
.switch { position: relative; flex: 0 0 auto; width: 42px; height: 23px; margin: 0; appearance: none; border: 0; border-radius: 20px; background: #d4dfeb; cursor: pointer; }
.switch::after { content: ""; position: absolute; top: 3px; left: 3px; width: 17px; height: 17px; border-radius: 50%; background: #fff; box-shadow: 0 2px 4px rgba(0,0,0,.12); transition: .2s ease; }
.switch:checked { background: var(--blue); }
.switch:checked::after { transform: translateX(19px); }
.node-option { display: flex; align-items: center; gap: 12px; padding: 13px 0; border-top: 1px solid #edf1f6; font-weight: 400; cursor: pointer; }
.node-option input { width: 16px; height: 16px; margin: 0; accent-color: var(--blue); }
.node-option span { flex: 1; }
.node-option b, .node-option small { display: block; }
.node-option b { margin-bottom: 4px; color: var(--ink); font-size: 13px; }
.node-option small { color: var(--muted); font-size: 11px; }
.node-option em { color: #22ac7c; font-size: 11px; font-style: normal; }
.submit-config { width: 100%; }
.config-preview { position: sticky; top: 88px; padding: 28px; background: #f7fbff; }
.preview-top { display: flex; justify-content: space-between; gap: 20px; align-items: start; padding-bottom: 22px; border-bottom: 1px solid #dbe9f7; }
.status-pill { display: inline-flex; align-items: center; gap: 6px; margin-bottom: 12px; color: #1ba87b; font-size: 11px; font-weight: 700; }
.status-pill i, .online-state i { display: inline-block; width: 7px; height: 7px; border-radius: 50%; background: var(--green); }
.preview-top h3 { margin-bottom: 0; font-size: 27px; letter-spacing: -.04em; }
.preview-code { padding: 6px 8px; color: var(--blue); border: 1px solid #c9e0fb; background: #fff; font-size: 11px; font-weight: 800; letter-spacing: .08em; }
.preview-route { display: grid; grid-template-columns: 1fr auto 1fr; gap: 12px; align-items: center; padding: 24px 0; }
.route-step span, .route-step strong { display: block; }
.route-step span { margin-bottom: 7px; color: #89a0ba; font-size: 11px; }
.route-step strong { font-size: 13px; word-break: break-all; }
.route-arrow { color: var(--blue); font-size: 20px; }
.preview-summary { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; padding: 18px 0; border-top: 1px solid #dbe9f7; border-bottom: 1px solid #dbe9f7; }
.preview-summary span, .preview-summary strong { display: block; }
.preview-summary span { margin-bottom: 7px; color: #89a0ba; font-size: 11px; }
.preview-summary strong { color: var(--blue); font-size: 12px; line-height: 1.5; }
.preview-json { margin-top: 21px; border: 1px solid #dbe9f7; background: #fff; }
.preview-json-head { display: flex; justify-content: space-between; padding: 11px 13px; border-bottom: 1px solid #e6eef7; color: #63758d; font-size: 12px; font-weight: 700; }
.preview-json-head button { border: 0; color: var(--blue); background: transparent; cursor: pointer; font-size: 11px; font-weight: 700; }
pre { min-height: 176px; margin: 0; padding: 14px; overflow: auto; color: #36516f; font-family: Consolas, monospace; font-size: 11px; line-height: 1.65; white-space: pre-wrap; }
.preview-note { margin: 18px 0 0; color: #8c9caf; font-size: 11px; line-height: 1.7; }

.plans-band { background: #f4f8ff; border-top: 1px solid #e5eef9; }
.plan-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.plan-card { padding: 29px; border: 1px solid #dfe9f4; background: #fff; }
.plan-card.is-featured { border-color: #7eb7f2; box-shadow: 0 13px 30px rgba(42, 116, 207, .12); }
.plan-card h3 { margin: 25px 0 15px; font-size: 21px; }
.plan-card > strong { display: block; margin-bottom: 12px; color: var(--blue); font-size: 32px; letter-spacing: -.05em; }
.plan-card > strong small { margin-left: 4px; color: #91a1b3; font-size: 12px; font-weight: 400; letter-spacing: 0; }
.plan-card p { min-height: 44px; color: var(--muted); font-size: 13px; line-height: 1.7; }
.text-link { padding: 0; border: 0; color: var(--blue); background: transparent; font-size: 13px; font-weight: 700; cursor: pointer; }
.account-panel { display: flex; justify-content: space-between; align-items: center; gap: 20px; padding: 22px 24px; border: 1px solid var(--line); background: #fbfdff; }
.account-panel strong, .account-panel span, .account-panel small { display: block; }
.account-panel strong { margin-bottom: 6px; font-size: 16px; }
.account-panel span, .account-panel small { color: var(--muted); font-size: 12px; }
.account-panel small { margin-top: 8px; color: var(--blue); }
.request-list { margin-top: 14px; border-top: 1px solid var(--line); }
.request-item { display: grid; grid-template-columns: 150px 1fr auto; gap: 14px; align-items: center; padding: 15px 8px; border-bottom: 1px solid var(--line); font-size: 13px; }
.request-item span, .request-item small { color: var(--muted); }
.node-section { padding-top: 86px; padding-bottom: 100px; }
.node-market { border-top: 1px solid var(--line); }
.market-row { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr auto; gap: 16px; align-items: center; padding: 19px 12px; border-bottom: 1px solid var(--line); font-size: 13px; }
.market-region { font-weight: 700; }
.market-latency, .market-capacity { color: var(--muted); }
.online-state { color: #22ac7c; font-size: 12px; }
.online-state i { margin-right: 5px; }
.mini-button { padding: 7px 13px; font-size: 12px; }
.cta-band { display: flex; justify-content: space-between; align-items: center; gap: 30px; padding: 68px max(32px, calc((100vw - 1160px) / 2)); color: #fff; background: linear-gradient(120deg, #1378dd, #1d6cdc); }
.cta-band h2 { margin-bottom: 10px; font-size: 34px; letter-spacing: -.04em; }
.cta-band p:last-child { margin-bottom: 0; color: rgba(255,255,255,.75); font-size: 14px; }
.modal-backdrop { position: fixed; inset: 0; z-index: 50; display: grid; place-items: center; padding: 20px; background: rgba(17, 40, 72, .32); }
.modal-backdrop[hidden] { display: none; }
.modal { position: relative; width: min(420px, 100%); padding: 32px; background: #fff; box-shadow: 0 22px 60px rgba(23, 62, 112, .25); }
.modal h2 { margin-bottom: 12px; font-size: 28px; }
.modal p:not(.eyebrow) { color: var(--muted); font-size: 13px; line-height: 1.7; }
.modal label { margin-top: 25px; }
.modal .button { width: 100%; margin-top: 20px; }
.modal-close { position: absolute; top: 12px; right: 15px; border: 0; color: #7b8ba0; background: transparent; cursor: pointer; font-size: 26px; }
.toast { position: fixed; right: 24px; bottom: 24px; z-index: 60; max-width: 320px; padding: 13px 17px; color: #fff; background: #1c3554; box-shadow: 0 11px 24px rgba(21, 49, 81, .22); opacity: 0; pointer-events: none; transform: translateY(10px); transition: .25s ease; font-size: 13px; }
.toast.is-visible { opacity: 1; transform: translateY(0); }

@media (max-width: 900px) {
  .site-header { gap: 14px; padding: 0 22px; }
  .brand { min-width: auto; }
  .main-nav { display: none; }
  .hero { display: block; min-height: 0; }
  .hero-blue { clip-path: none; }
  .hero-copy { padding: 82px 28px 68px; }
  .hero-art { min-height: 430px; }
  .section-tabs { width: calc(100% - 32px); margin-top: -1px; }
  .content-section { width: min(100% - 36px, 680px); padding: 78px 0; }
  .section-heading { display: block; }
  .section-heading > p { margin-top: 20px; }
  .advantage-grid, .scenario-grid, .plan-grid { grid-template-columns: 1fr; gap: 18px; }
  .config-layout { grid-template-columns: 1fr; }
  .config-preview { position: static; }
  .architecture-visual { flex-direction: column; }
  .flow-line { width: 1px; height: 34px; }
  .market-row { grid-template-columns: 1.6fr 1fr 1fr auto; }
  .market-capacity { display: none; }
}

@media (max-width: 540px) {
  .site-header { height: 58px; padding: 0 16px; }
  .brand strong { font-size: 14px; }
  .account-button { padding: 0 9px; font-size: 11px; }
  h1 { font-size: 54px; }
  .hero-lead { font-size: 24px; }
  .hero-stats { gap: 14px; }
  .hero-stats > div, .hero-stats > div + div { padding: 0; border: 0; }
  .hero-stats { grid-template-columns: 1fr; }
  .hero-stats span { margin-top: 3px; }
  .section-tabs { grid-template-columns: repeat(2, 1fr); }
  .feature-row { grid-template-columns: 1fr; gap: 12px; padding: 27px 12px; }
  .form-grid, .platform-options, .preview-summary { grid-template-columns: 1fr; }
  .config-form, .config-preview { padding: 20px; }
  .preview-route { grid-template-columns: 1fr; }
  .route-arrow { transform: rotate(90deg); justify-self: start; }
  .market-row { grid-template-columns: 1fr auto; gap: 9px; }
  .market-latency { grid-column: 1; }
  .online-state { grid-column: 2; grid-row: 1; }
  .mini-button { grid-column: 2; grid-row: 2; }
  .cta-band { display: block; padding: 55px 28px; }
  .cta-band .button { margin-top: 20px; }
}