/* 源点首页（浅色）。色值取自 VI：源点蓝做操作色，电光青、玉青只用于大面积色块和图形，不用于白底小字。 */
:root {
  --wrap: 1200px; --nav-h: 76px;
  --sky: #EAF3FF; --cyan-soft: #E3F8FC; --jade-soft: #E5F7F2; --blue-deep: #0546B0;
  /* Variables used by the shared demo dialog in features.css. */
  --site-background: #FFFFFF; --site-surface: #F4F8FC; --site-accent: #0757D9; --site-accent-soft: #E6EFFB;
  --site-button-text: #FFFFFF; --site-hover-line: #AFC9E8; --site-shadow: #10223A0D;
}
html { scroll-behavior: smooth; }
body { background: #fff; color: var(--yd-text); font-size: 16px; line-height: 1.7; }
h1, h2, h3, p, ul, ol, dl, dd, figure { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img { max-width: 100%; display: block; }
.wrap { width: calc(100% - 96px); max-width: var(--wrap); margin-inline: auto; }
.nw { white-space: nowrap; }
.skip { position: fixed; left: 16px; top: -80px; z-index: 50; background: var(--yd-blue); color: #fff; padding: 10px 14px; border-radius: var(--yd-radius-sm); }
.skip:focus { top: 12px; }
:focus-visible { outline: 3px solid var(--yd-blue); outline-offset: 3px; border-radius: 4px; }
section[id] { scroll-margin-top: var(--nav-h); }

/* Buttons */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 10px; min-height: 54px; padding: 12px 26px; border-radius: 10px; border: 1px solid transparent; font-size: 1rem; font-weight: 600; line-height: 1.3; cursor: pointer; transition: background var(--yd-duration), border-color var(--yd-duration), color var(--yd-duration), box-shadow var(--yd-duration), transform var(--yd-duration); }
.btn svg { flex: none; }
.btn-blue { background: var(--yd-blue); color: #fff; box-shadow: 0 10px 24px -10px #0757D9AA; }
.btn-blue:hover { background: var(--blue-deep); transform: translateY(-1px); }
.btn-line { background: #fff; color: var(--yd-text); border-color: var(--yd-line); }
.btn-line svg { color: var(--yd-blue); }
.btn-line:hover { border-color: var(--yd-blue); color: var(--yd-blue); }
.btn-soft { min-height: 46px; padding: 10px 20px; background: #fff; color: var(--yd-blue); border-color: #C9DAF3; font-size: .9375rem; }
.btn-soft:hover:not(:disabled) { border-color: var(--yd-blue); }
.btn-white { background: #fff; color: var(--yd-blue); }
.btn-white:hover { transform: translateY(-1px); box-shadow: 0 12px 24px -12px #0006; }
.btn:disabled, .tool-play:disabled { opacity: .5; cursor: default; transform: none; }

/* Navigation */
.nav { position: sticky; top: 0; z-index: 30; height: var(--nav-h); background: rgba(255,255,255,.85); backdrop-filter: saturate(1.4) blur(14px); -webkit-backdrop-filter: saturate(1.4) blur(14px); border-bottom: 1px solid transparent; transition: border-color var(--yd-duration); }
.nav.solid { border-bottom-color: var(--yd-line); }
.nav-row { height: 100%; display: flex; align-items: center; justify-content: space-between; gap: 32px; }
.brand { display: block; padding-block: 8px; }
.brand img { width: 150px; height: auto; }
.nav-links { display: flex; align-items: center; gap: 28px; font-size: .9375rem; }
.nav-links > a { color: var(--yd-muted); padding-block: 10px; transition: color var(--yd-duration); }
.nav-links > a:hover { color: var(--yd-blue); }
.nav-links .nav-group { display: inline-flex; align-items: center; gap: 8px; color: var(--yd-blue); background: var(--sky); border-radius: 10px; padding: 9px 16px; font-weight: 600; }
.nav-links .nav-group:hover { background: #DCEBFF; }
.nav-links .nav-login { color: var(--yd-text); border: 1px solid var(--yd-line); border-radius: 10px; padding: 8px 18px; margin-left: -8px; }
.nav-links .nav-login:hover { border-color: var(--yd-blue); color: var(--yd-blue); }
.menu { display: none; }

/* Hero */
.hero { position: relative; overflow: hidden; padding: 64px 0 24px; background: linear-gradient(180deg, #F3F8FF 0%, #FFFFFF 82%); }
.ripples { position: absolute; width: 860px; height: 860px; right: -230px; top: -60px; pointer-events: none; border-radius: 50%; border: 1.5px solid #CFE3FB; }
.ripples::before, .ripples::after { content: ''; position: absolute; border-radius: 50%; border: 1.5px solid #DDEBFC; }
.ripples::before { inset: 70px; } .ripples::after { inset: 150px; border-color: #E7F1FD; }
.glow { position: absolute; pointer-events: none; border-radius: 50%; filter: blur(60px); }
.glow.g1 { width: 420px; height: 420px; right: 60px; top: 120px; background: #A9EEF9; opacity: .55; }
.glow.g2 { width: 360px; height: 360px; right: 300px; top: 360px; background: #BFD7FF; opacity: .6; }
.hero-grid { position: relative; display: grid; grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr); gap: 40px; align-items: center; min-height: 640px; }
.kicker { display: inline-flex; align-items: center; gap: 10px; padding: 6px 14px 6px 6px; border-radius: 999px; background: #fff; border: 1px solid #D6E5F7; font-size: .875rem; font-weight: 500; box-shadow: 0 4px 14px -8px #0757D955; }
.kicker img { width: 26px; height: 26px; padding: 4px; border-radius: 50%; background: var(--sky); }
.hero h1 { margin-top: 26px; font-size: clamp(3.5rem, 5.6vw, 4.75rem); line-height: 1.16; font-weight: 700; letter-spacing: -.04em; }
.hero h1 .accent { position: relative; z-index: 0; display: inline-block; color: var(--yd-blue); white-space: nowrap; }
.hero h1 .accent::after { content: ''; position: absolute; left: 2%; right: 4%; bottom: .02em; height: .24em; background: var(--yd-cyan); opacity: .55; border-radius: 99px; z-index: -1; }
.hero-sub { margin-top: 22px; font-size: 1.1875rem; line-height: 1.8; color: #3C4E66; }
.pill { display: inline-flex; align-items: center; gap: 10px; margin-top: 22px; padding: 9px 18px 9px 10px; border-radius: 999px; background: var(--cyan-soft); color: #0B4B5B; font-size: .9375rem; font-weight: 500; }
.pill-icon { display: grid; place-items: center; width: 28px; height: 28px; border-radius: 50%; background: #fff; color: var(--yd-blue); }
.actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 32px; }

/* Phone mock-up */
.hero-visual { position: relative; display: flex; justify-content: center; padding-block: 40px; }
.phone { position: relative; width: 340px; border-radius: 46px; padding: 12px; background: #0F1B2D; box-shadow: 0 50px 90px -30px #0B2A5A66, 0 20px 40px -20px #0B2A5A55, inset 0 0 0 2px #2A3B52; }
.phone-screen { border-radius: 36px; overflow: hidden; background: #DCEAF7 url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120' viewBox='0 0 120 120'%3E%3Cg fill='none' stroke='%23C6DAEE' stroke-width='1.2'%3E%3Cpath d='M10 30q10-12 20 0t20 0'/%3E%3Cpath d='M70 90q10-12 20 0t20 0'/%3E%3Ccircle cx='90' cy='30' r='6'/%3E%3Ccircle cx='28' cy='88' r='4'/%3E%3C/g%3E%3C/svg%3E"); }
.tg-bar { display: flex; align-items: center; gap: 10px; padding: 34px 16px 12px; background: #fff; border-bottom: 1px solid #E3EAF2; }
.tg-bar .back { color: var(--yd-blue); font-size: 1.25rem; line-height: 1; }
.tg-bar img { width: 36px; height: 36px; padding: 6px; border-radius: 50%; background: var(--yd-ink); }
.tg-bar strong { display: block; font-size: .9375rem; line-height: 1.3; }
.tg-bar span { display: block; font-size: .75rem; color: var(--yd-muted); line-height: 1.3; }
.tg-body { display: grid; gap: 8px; padding: 14px 12px 18px; min-height: 470px; align-content: start; }
.bub { max-width: 86%; padding: 8px 12px; border-radius: 16px; font-size: .8125rem; line-height: 1.55; box-shadow: 0 1px 1px #0B2A5A14; }
.bub.me { justify-self: end; background: #DFF6CF; border-bottom-right-radius: 5px; color: #17301A; }
.bub.bot { justify-self: start; background: #fff; border-bottom-left-radius: 5px; }
.bub time { display: block; text-align: right; font-size: .625rem; color: #6D8BA6; margin-top: 1px; }
.bub .ru { display: block; margin-top: 6px; padding: 6px 9px; border-left: 2.5px solid var(--yd-blue); background: var(--sky); border-radius: 0 8px 8px 0; color: #1C3556; }
.bub .zh { display: block; margin-top: 5px; color: var(--yd-success); font-size: .75rem; }
.bub.card { padding: 10px 12px; background: #fff; }
.bub.card b { display: flex; align-items: center; gap: 6px; color: var(--yd-success); font-size: .75rem; }
.bub.card dl { display: grid; grid-template-columns: auto 1fr; gap: 2px 10px; margin-top: 6px; font-size: .75rem; }
.bub.card dt { color: var(--yd-muted); } .bub.card dd { font-weight: 500; }
.tg-input { display: flex; align-items: center; gap: 8px; margin: 0 10px 12px; padding: 9px 14px; border-radius: 22px; background: #fff; color: #93A6BA; font-size: .8125rem; }
.tg-input span:last-child { margin-left: auto; color: var(--yd-blue); }
.float { position: absolute; z-index: 2; background: #fff; border-radius: 16px; padding: 14px 16px; box-shadow: 0 24px 48px -20px #0B2A5A40, 0 2px 6px -2px #0B2A5A1A; border: 1px solid #E5EEF8; }
.float .f-value { font-size: .9375rem; font-weight: 600; }
.f1 { left: -20px; top: 6px; } .f2 { right: -30px; top: 250px; } .f3 { left: -30px; bottom: 6px; }
.lang { display: flex; align-items: center; gap: 10px; }
.chip { padding: 4px 10px; border-radius: 8px; font-size: .8125rem; font-weight: 600; }
.chip.zh { background: var(--sky); color: var(--yd-blue); }
.chip.ru { background: var(--jade-soft); color: var(--yd-success); }
.lang .arrow { color: var(--yd-muted); }
.row { display: flex; align-items: center; gap: 12px; }
.icon-tile { display: grid; place-items: center; width: 40px; height: 40px; border-radius: 12px; flex: none; }
.icon-tile.blue { background: var(--sky); color: var(--yd-blue); }
.icon-tile.jade { background: var(--jade-soft); color: var(--yd-success); }
.icon-tile.cyan { background: var(--cyan-soft); color: #0A7186; }
@media (prefers-reduced-motion: no-preference) {
  .float { animation: bob 6s ease-in-out infinite; }
  .f2 { animation-delay: -3s; }
  @keyframes bob { 50% { transform: translateY(-8px); } }
  .tg-body > * { opacity: 0; transform: translateY(6px); animation: pop .35s cubic-bezier(.2,.7,.2,1) forwards; animation-delay: calc(.4s + var(--d) * .8s); }
  @keyframes pop { to { opacity: 1; transform: none; } }
}

/* Values */
.values { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; padding-block: 48px 8px; }
.value { padding: 28px; border-radius: 20px; background: var(--yd-paper); border: 1px solid #E3ECF6; }
.value h2 { margin-top: 18px; font-size: 1.25rem; line-height: 1.4; font-weight: 650; letter-spacing: 0; }
.value p { margin-top: 6px; color: var(--yd-muted); }

/* Sections */
.section { padding-block: 104px; }
.section-soft { background: var(--yd-paper); }
.sec-title { text-align: center; margin-bottom: 56px; font-size: 2.75rem; line-height: 1.3; font-weight: 700; letter-spacing: -.03em; }

/* Core features (generated) */
.core-list { display: grid; gap: 28px; }
.core { display: grid; grid-template-columns: minmax(0, .8fr) minmax(0, 1.2fr); gap: 64px; align-items: center; padding: 56px; border-radius: 32px; background: var(--tint); }
.core-reverse { grid-template-columns: minmax(0, 1.2fr) minmax(0, .8fr); }
.core-reverse .core-copy { order: 2; }
.core-blue { --tint: linear-gradient(135deg, #EEF5FF, #F7FBFF); --role: var(--yd-blue); }
.core-cyan { --tint: linear-gradient(135deg, #E8F9FC, #F6FDFE); --role: #0A6577; }
.core-jade { --tint: linear-gradient(135deg, #E9F8F3, #F7FDFB); --role: var(--yd-success); }
.core-paper { --tint: linear-gradient(135deg, #F1F4FA, #FAFBFD); --role: var(--yd-blue); }
.core-roles { display: flex; flex-wrap: wrap; gap: 8px; }
.core-roles span { padding: 5px 14px; border-radius: 999px; background: #fff; color: var(--role); font-size: .875rem; font-weight: 600; box-shadow: 0 2px 8px -4px #0B2A5A33; }
.core h3 { margin-top: 20px; font-size: 2.125rem; line-height: 1.3; font-weight: 700; letter-spacing: -.025em; }
.core-lead { margin: 12px 0 28px; font-size: 1.125rem; color: #3C4E66; }
.core-shot img { width: 100%; height: auto; border-radius: 20px; box-shadow: 0 40px 70px -36px #0B2A5A55, 0 8px 20px -12px #0B2A5A33; }

/* All features (generated) */
.tools { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; }
.tool { display: flex; flex-direction: column; padding: 24px; border-radius: 20px; background: #fff; border: 1px solid #E3ECF6; }
.tool-icon { display: grid; place-items: center; width: 44px; height: 44px; border-radius: 12px; background: var(--sky); color: var(--yd-blue); }
.tool:nth-child(3n+2) .tool-icon { background: var(--cyan-soft); color: #0A7186; }
.tool:nth-child(3n) .tool-icon { background: var(--jade-soft); color: var(--yd-success); }
.tool h3 { margin-top: 18px; font-size: 1.125rem; font-weight: 650; }
.tool p { flex: 1; margin-top: 6px; color: var(--yd-muted); font-size: .9375rem; line-height: 1.7; }
.tool-play { display: inline-flex; align-items: center; gap: 8px; align-self: flex-start; min-height: 40px; margin-top: 16px; padding: 0 2px; border: 0; background: none; color: var(--yd-blue); font-size: .9375rem; font-weight: 600; cursor: pointer; }
.tool-play:hover:not(:disabled) { text-decoration: underline; text-underline-offset: 4px; }

/* Getting started */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; counter-reset: none; }
.step { position: relative; padding: 32px 28px; border-radius: 20px; background: #fff; border: 1px solid #E3ECF6; }
.step-no { display: grid; place-items: center; width: 40px; height: 40px; border-radius: 50%; background: var(--yd-blue); color: #fff; font-weight: 700; }
.step h3 { margin-top: 20px; font-size: 1.25rem; font-weight: 650; }
.step p { margin-top: 6px; color: var(--yd-muted); }
.price { display: flex; align-items: center; justify-content: space-between; gap: 24px; margin-top: 20px; padding: 24px 28px; border-radius: 20px; background: var(--sky); }
.price strong { font-weight: 650; margin-right: 8px; }
.price p { color: #3C4E66; }

/* FAQ */
.faq-grid { display: grid; grid-template-columns: minmax(0, .7fr) minmax(0, 1.3fr); gap: 64px; align-items: start; }
.faq-grid .sec-title { text-align: left; margin-bottom: 0; }
.faq-list { border-top: 1px solid var(--yd-line); }
.faq-list details { border-bottom: 1px solid var(--yd-line); }
.faq-list summary { position: relative; list-style: none; cursor: pointer; padding: 22px 44px 22px 0; font-size: 1.0625rem; font-weight: 600; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::before, .faq-list summary::after { content: ''; position: absolute; right: 8px; top: 50%; width: 14px; height: 2px; border-radius: 2px; background: var(--yd-blue); transition: transform var(--yd-duration); }
.faq-list summary::after { transform: rotate(90deg); }
.faq-list details[open] summary::after { transform: rotate(0); }
.faq-list summary:hover { color: var(--yd-blue); }
.faq-list details p { padding: 0 44px 22px 0; color: var(--yd-muted); }

/* Join the support group */
.join { padding-block: 0 104px; }
.join-box { display: flex; align-items: center; justify-content: space-between; gap: 32px; padding: 48px 56px; border-radius: 32px; background: linear-gradient(120deg, var(--yd-blue) 0%, #1F74E8 60%, #33B9DD 120%); color: #fff; }
.join-box h2 { font-size: 2rem; line-height: 1.35; font-weight: 700; letter-spacing: -.02em; }

/* Footer */
.footer { padding-block: 40px; border-top: 1px solid var(--yd-line); color: var(--yd-muted); font-size: .875rem; }
.footer-top { display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
.footer-top .brand img { width: 130px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 8px 24px; }
.footer-links a:hover, .footer-legal a:hover { color: var(--yd-blue); }
.footer-legal { display: flex; flex-wrap: wrap; gap: 4px 20px; margin-top: 20px; font-size: .8125rem; }
.footer-legal > * { white-space: nowrap; }
.faq-list details p a { color: var(--yd-blue); text-decoration: underline; text-underline-offset: 3px; }

/* Mobile floating support-group button */
.float-group { display: none; }

@media (max-width: 1100px) {
  .wrap { width: calc(100% - 64px); }
  .nav-links { gap: 18px; }
  .core { padding: 40px; gap: 40px; }
  .f1 { left: -30px; } .f2 { right: -30px; }
  .tools { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 960px) {
  .menu { display: inline-flex; flex-direction: column; justify-content: center; align-items: center; gap: 6px; width: 44px; height: 44px; border: 1px solid var(--yd-line); border-radius: 10px; background: #fff; }
  .menu span { width: 18px; height: 1.5px; background: var(--yd-text); transition: transform var(--yd-duration); }
  .menu[aria-expanded="true"] span:first-child { transform: translateY(3.75px) rotate(45deg); }
  .menu[aria-expanded="true"] span:last-child { transform: translateY(-3.75px) rotate(-45deg); }
  .nav-links { display: none; position: absolute; top: var(--nav-h); left: 0; right: 0; flex-direction: column; align-items: stretch; gap: 4px; padding: 12px 32px 24px; background: #fff; border-bottom: 1px solid var(--yd-line); box-shadow: 0 20px 30px -20px #0B2A5A33; }
  .nav-links.open { display: flex; }
  .nav-links > a { padding: 12px 0; font-size: 1rem; }
  .nav-links .nav-group, .nav-links .nav-login { justify-content: center; margin: 8px 0 0; padding: 12px; }
  .hero-grid { grid-template-columns: 1fr; min-height: 0; }
  .hero-visual { padding-block: 24px 40px; }
  .values, .steps { grid-template-columns: 1fr; }
  .core, .core-reverse { grid-template-columns: 1fr; }
  .core-reverse .core-copy { order: 0; }
  .faq-grid { grid-template-columns: 1fr; gap: 28px; }
  .faq-grid .sec-title { text-align: center; }
  .join-box, .price { flex-direction: column; align-items: flex-start; }
}
@media (max-width: 700px) {
  :root { --nav-h: 64px; }
  .wrap { width: calc(100% - 40px); }
  .nav-links { padding-inline: 20px; }
  .brand img { width: 128px; }
  .hero { padding-top: 36px; }
  .hero h1 { font-size: 2.625rem; line-height: 1.22; }
  .hero-sub { font-size: 1.0625rem; }
  .pill { font-size: .875rem; }
  .actions { flex-direction: column; }
  .actions .btn { width: 100%; }
  .phone { width: 300px; }
  .f1 { left: -6px; top: 0; } .f2 { right: -6px; top: 360px; } .f3 { display: none; }
  .float { padding: 10px 12px; }
  .values { padding-top: 32px; }
  .section { padding-block: 64px; }
  .sec-title { margin-bottom: 32px; font-size: 1.875rem; }
  .core { padding: 28px 20px; border-radius: 24px; gap: 28px; }
  .core h3 { font-size: 1.625rem; }
  .core-lead { font-size: 1rem; margin-bottom: 22px; }
  .core .btn-soft { width: 100%; }
  .tools { grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 12px; }
  .tool { padding: 18px 16px; }
  .tool p { font-size: .875rem; }
  .join { padding-bottom: 64px; }
  .join-box { padding: 32px 24px; border-radius: 24px; }
  .join-box h2 { font-size: 1.5rem; }
  .join-box .btn, .price .btn { width: 100%; }
  .faq-list summary { font-size: 1rem; }
  .footer-legal { line-height: 1.9; }
  .float-group { display: flex; position: fixed; right: 16px; bottom: calc(16px + env(safe-area-inset-bottom)); z-index: 25; width: 56px; height: 56px; align-items: center; justify-content: center; border-radius: 50%; background: var(--yd-blue); color: #fff; box-shadow: 0 12px 26px -8px #0757D9AA; opacity: 0; transform: translateY(12px) scale(.9); pointer-events: none; transition: opacity var(--yd-duration), transform var(--yd-duration); }
  body.past-hero .float-group { opacity: 1; transform: none; pointer-events: auto; }
  body.menu-open .float-group, body:has(dialog[open]) .float-group { opacity: 0; pointer-events: none; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}

/* Legal pages */
.legal-back { color: var(--yd-blue); font-weight: 600; font-size: .9375rem; }
.legal { max-width: 760px; padding-block: 56px 96px; }
.legal h1 { font-size: 2.5rem; line-height: 1.3; font-weight: 700; letter-spacing: -.03em; }
.legal-date { margin-top: 8px; color: var(--yd-muted); font-size: .875rem; }
.legal-intro { margin-top: 28px; padding: 18px 22px; border-radius: 14px; background: var(--sky); color: #2B3F5A; }
.legal section { margin-top: 40px; }
.legal h2 { font-size: 1.375rem; line-height: 1.4; font-weight: 650; }
.legal section p, .legal section ul { margin-top: 12px; color: #33465F; }
.legal section ul { padding-left: 1.25em; list-style: disc; }
.legal section li + li { margin-top: 6px; }
.legal b { color: var(--yd-text); font-weight: 600; }
.legal a { color: var(--yd-blue); text-decoration: underline; text-underline-offset: 3px; }
.legal .legal-facts { list-style: none; padding: 0; margin-top: 16px; border: 1px solid var(--yd-line); border-radius: 14px; overflow: hidden; }
.legal .legal-facts li { display: grid; grid-template-columns: 7em 1fr; gap: 16px; padding: 12px 18px; margin: 0; }
.legal .legal-facts li + li { border-top: 1px solid var(--yd-line); }
.legal .legal-facts span { color: var(--yd-muted); }
@media (max-width: 700px) { .legal { padding-block: 32px 64px; } .legal h1 { font-size: 1.875rem; } .legal .legal-facts li { grid-template-columns: 1fr; gap: 2px; } }