:root {
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  color: #17243a;
  background: #f3f7ff;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  --bg: #f3f7ff;
  --surface: #fff;
  --line: #d9e2f1;
  --text: #17243a;
  --muted: #687790;
  --accent: #4f7cf7;
  --accent-2: #4bb9e8;
  --accent-rgb: 79, 124, 247;
  --accent-2-rgb: 75, 185, 232;
  --shadow: 0 16px 42px rgba(54, 85, 148, .1);
}

* { box-sizing: border-box; }
html { max-width: 100%; overflow-x: hidden; scroll-behavior: smooth; }
body { max-width: 100%; margin: 0; min-width: 320px; min-height: 100vh; overflow-x: hidden; background: var(--bg); }
button, a { font: inherit; }
button { cursor: pointer; }
a { color: inherit; text-decoration: none; }
button:focus-visible, a:focus-visible { outline: 3px solid rgba(var(--accent-rgb), .22); outline-offset: 2px; }
[hidden] { display: none !important; }

.site-shell {
  position: relative;
  isolation: isolate;
  min-height: 100vh;
  overflow: hidden;
  color: var(--text);
  background:
    radial-gradient(circle at 13% 16%, rgba(var(--accent-rgb), .08), transparent 31rem),
    radial-gradient(circle at 88% 78%, rgba(var(--accent-2-rgb), .06), transparent 34rem),
    var(--bg);
}

.site-shell::before,
.site-shell::after {
  position: absolute;
  z-index: -1;
  width: 420px;
  height: 420px;
  border-radius: 50%;
  filter: blur(18px);
  content: "";
  pointer-events: none;
  animation: ambient-float 14s ease-in-out infinite alternate;
}

.site-shell::before { top: 12%; left: -210px; background: radial-gradient(circle, rgba(var(--accent-rgb), .13), transparent 68%); }
.site-shell::after { top: 58%; right: -220px; background: radial-gradient(circle, rgba(var(--accent-2-rgb), .12), transparent 68%); animation-delay: -6s; }

.skip-link { position: fixed; z-index: 200; top: 10px; left: 10px; padding: 9px 13px; transform: translateY(-150%); border-radius: 8px; color: #fff; background: var(--accent); }
.skip-link:focus { transform: translateY(0); }

.topbar { position: sticky; z-index: 10; top: 0; border-bottom: 1px solid var(--line); background: rgba(243, 247, 255, .94); backdrop-filter: blur(12px); animation: topbar-enter .55s ease both; }
.topbar-inner { display: flex; width: min(1180px, calc(100% - 32px)); min-height: 68px; align-items: center; gap: 20px; margin: 0 auto; }
.brand-home { display: inline-flex; min-width: 52px; min-height: 34px; align-items: center; justify-content: center; padding: 0 10px; border: 1px solid rgba(var(--accent-rgb), .42); border-radius: 8px; color: var(--accent); background: rgba(var(--accent-rgb), .06); font-size: 14px; font-weight: 800; }
.topbar-ticker { position: relative; height: 34px; min-width: 140px; flex: 1; overflow: hidden; border: 1px solid rgba(var(--accent-rgb), .22); border-radius: 8px; color: var(--muted); background: rgba(255, 255, 255, .72); font-size: 14px; line-height: 32px; }
.topbar-ticker::before, .topbar-ticker::after { position: absolute; z-index: 1; top: 0; bottom: 0; width: 36px; content: ""; pointer-events: none; }
.topbar-ticker::before { left: 0; background: linear-gradient(90deg, #fff, transparent); }
.topbar-ticker::after { right: 0; background: linear-gradient(270deg, #fff, transparent); }
.topbar-ticker-track { display: inline-block; min-width: 100%; padding-left: 100%; white-space: nowrap; animation: ticker-scroll 18s linear infinite; }

.button { position: relative; display: inline-flex; min-height: 40px; align-items: center; justify-content: center; overflow: hidden; padding: 0 16px; border: 1px solid transparent; border-radius: 8px; color: #fff; background: linear-gradient(135deg, var(--accent), var(--accent-2)); font-weight: 800; white-space: nowrap; transition: transform .14s ease, filter .14s ease; }
.button::after { position: absolute; top: -80%; left: -45%; width: 34%; height: 260%; transform: rotate(22deg); background: linear-gradient(90deg, transparent, rgba(255, 255, 255, .42), transparent); content: ""; transition: left .55s ease; }
.button:hover { transform: translateY(-1px); filter: brightness(1.03); }
.button:hover::after { left: 120%; }
.button.secondary { border-color: var(--line); color: var(--text); background: var(--surface); }
.topbar-download { flex: 0 0 auto; }

.page { width: min(1180px, calc(100% - 32px)); margin: 0 auto; }
.hero { display: grid; min-height: calc(100vh - 68px); align-items: center; padding: 52px 0; grid-template-columns: minmax(0, 1.05fr) minmax(320px, .95fr); gap: 36px; }
.hero > * { min-width: 0; }
.eyebrow, .section-kicker, .panel-label { margin: 0 0 14px; color: var(--accent); font-size: 12px; font-weight: 800; letter-spacing: .04em; }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 18px; font-size: clamp(52px, 6vw, 72px); line-height: 1.02; letter-spacing: -.045em; }
.lead { margin-bottom: 24px; color: var(--muted); font-size: 18px; line-height: 1.7; }
.inline-actions { display: flex; flex-wrap: wrap; gap: 10px; }

[data-reveal] { transform: translateY(26px); opacity: 0; transition: transform .72s cubic-bezier(.2, .7, .2, 1) var(--reveal-delay, 0ms), opacity .72s ease var(--reveal-delay, 0ms); }
[data-reveal].is-visible { transform: translateY(0); opacity: 1; }
.announcement-visual { position: relative; width: 100%; min-height: 420px; overflow: hidden; border: 1px solid var(--line); border-radius: 8px; background: linear-gradient(120deg, rgba(var(--accent-rgb), .12), transparent 44%), linear-gradient(300deg, rgba(var(--accent-2-rgb), .13), transparent 52%), var(--surface); box-shadow: var(--shadow); transition: transform .35s ease, box-shadow .35s ease, border-color .35s ease; }
.announcement-visual:hover { transform: translateY(-5px); border-color: rgba(var(--accent-rgb), .34); box-shadow: 0 26px 60px rgba(54, 85, 148, .16); }
.announcement-visual::after { position: absolute; z-index: 1; top: 0; bottom: 0; left: -45%; width: 34%; transform: skewX(-18deg); background: linear-gradient(90deg, transparent, rgba(255, 255, 255, .38), transparent); content: ""; animation: panel-sheen 7s ease-in-out infinite; pointer-events: none; }
.visual-grid { position: absolute; inset: 0; background-image: linear-gradient(rgba(22, 32, 42, .06) 1px, transparent 1px), linear-gradient(90deg, rgba(22, 32, 42, .06) 1px, transparent 1px); background-size: 32px 32px; mask-image: linear-gradient(to bottom, rgba(0, 0, 0, .9), transparent 78%); animation: grid-drift 22s linear infinite; }
.announcement-panel { position: absolute; z-index: 2; inset: 24px; display: flex; min-height: 0; overflow: hidden; padding: 22px; border: 1px solid rgba(var(--accent-rgb), .24); border-radius: 8px; background: rgba(255, 255, 255, .92); box-shadow: 0 18px 50px rgba(15, 36, 60, .1); backdrop-filter: blur(7px); flex-direction: column; transition: border-color .3s ease, background .3s ease; }
.announcement-visual:hover .announcement-panel { border-color: rgba(var(--accent-rgb), .36); background: rgba(255, 255, 255, .96); }
.panel-label-row { display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.panel-label-row > span { color: var(--muted); font-size: 11px; white-space: nowrap; }
.announcement-panel h2 { margin-bottom: 18px; font-size: 24px; }
.announcement-body { min-height: 0; overflow-y: auto; color: var(--muted); font-size: 16px; line-height: 1.75; overflow-wrap: anywhere; }
.announcement-body p { margin-bottom: 10px; white-space: pre-wrap; }

.section { padding: 64px 0 72px; border-top: 1px solid var(--line); scroll-margin-top: 68px; }
.section-header { display: flex; width: min(760px, 100%); align-items: end; justify-content: space-between; gap: 16px; margin: 0 auto 24px; }
.section-header h2 { margin-bottom: 0; font-size: 30px; }
.section-header > span { color: var(--accent); font-size: 13px; font-weight: 700; }

.version-platform-grid { display: grid; width: min(760px, 100%); margin: 0 auto; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
.version-platform-card { --card-accent: #4f7cf7; --card-rgb: 79, 124, 247; position: relative; display: flex; min-width: 0; min-height: 580px; overflow: hidden; padding: 22px; border: 1px solid rgba(var(--card-rgb), .2); border-radius: 12px; background: linear-gradient(145deg, rgba(var(--card-rgb), .055), transparent 55%), var(--surface); box-shadow: 0 18px 52px rgba(54, 85, 148, .1); flex-direction: column; transition: transform .3s ease, border-color .3s ease, box-shadow .3s ease; }
.version-platform-card::before { position: absolute; top: 0; right: 18%; left: 18%; height: 2px; background: linear-gradient(90deg, transparent, var(--card-accent), transparent); content: ""; }
.version-platform-card::after { position: absolute; right: -100px; bottom: -135px; width: 270px; height: 270px; border: 1px dashed rgba(var(--card-rgb), .12); border-radius: 50%; box-shadow: 0 0 0 34px rgba(var(--card-rgb), .022), 0 0 0 68px rgba(var(--card-rgb), .012); content: ""; pointer-events: none; animation: update-orbit 19s linear infinite; }
.version-platform-card--android { --card-accent: #4f7cf7; --card-rgb: 79, 124, 247; }
.version-platform-card--ios { --card-accent: #667be6; --card-rgb: 102, 123, 230; }
.version-platform-card--windows { --card-accent: #5369d5; --card-rgb: 83, 105, 213; }
.version-platform-card--linux { --card-accent: #477ec9; --card-rgb: 71, 126, 201; }
.version-platform-card:hover { transform: translateY(-6px); border-color: rgba(var(--card-rgb), .35); box-shadow: 0 27px 66px rgba(54, 85, 148, .15); }
.version-platform-card[data-available="true"] { border-color: rgba(var(--card-rgb), .3); }

.version-platform-cover { position: relative; z-index: 1; width: 100%; overflow: hidden; border: 1px solid rgba(var(--card-rgb), .16); border-radius: 12px; background: #edf3ff; aspect-ratio: 16 / 10; box-shadow: 0 15px 34px rgba(var(--card-rgb), .16); }
.version-platform-cover::after { position: absolute; z-index: 2; inset: 42% 0 0; background: linear-gradient(180deg, transparent, rgba(13, 27, 66, .48)); content: ""; pointer-events: none; }
.version-platform-cover-placeholder { position: relative; display: grid; width: 100%; height: 100%; place-content: center; overflow: hidden; color: #fff; background: linear-gradient(145deg, #3655b8, #5e86e7 62%, #76a8e9); text-align: center; }
.version-platform-card--ios .version-platform-cover-placeholder { background: linear-gradient(145deg, #4a55b2, #7184df 62%, #9ba8ee); }
.version-platform-card--windows .version-platform-cover-placeholder { background: linear-gradient(145deg, #384ba5, #586fd0 62%, #7d8ce2); }
.version-platform-card--linux .version-platform-cover-placeholder { background: linear-gradient(145deg, #315d9f, #4f82c8 62%, #79a4dc); }
.version-platform-cover-placeholder::before { position: absolute; inset: 0; background-image: linear-gradient(rgba(255, 255, 255, .1) 1px, transparent 1px), linear-gradient(90deg, rgba(255, 255, 255, .1) 1px, transparent 1px); background-size: 28px 28px; content: ""; }
.version-platform-cover-placeholder::after { position: absolute; top: 50%; left: 50%; width: 165px; height: 165px; border: 1px dashed rgba(255, 255, 255, .25); border-radius: 50%; transform: translate(-50%, -50%); content: ""; animation: orbit-spin 18s linear infinite; }
.version-platform-cover-placeholder i { position: absolute; top: 50%; left: 50%; width: 105px; height: 105px; border: 1px solid rgba(255, 255, 255, .2); border-radius: 50%; transform: translate(-50%, -50%); }
.version-platform-cover-placeholder span, .version-platform-cover-placeholder small { position: relative; z-index: 1; }
.version-platform-cover-placeholder span { font-size: 48px; font-weight: 900; letter-spacing: -.06em; text-shadow: 0 8px 24px rgba(20, 39, 93, .28); }
.version-platform-cover-placeholder small { margin-top: 8px; font-size: 8px; font-weight: 900; letter-spacing: .15em; opacity: .82; }
.version-platform-cover-label { position: absolute; z-index: 3; bottom: 12px; left: 12px; padding: 6px 8px; border: 1px solid rgba(255, 255, 255, .25); border-radius: 7px; color: #fff; background: rgba(20, 38, 82, .24); backdrop-filter: blur(8px); font-size: 8px; font-weight: 900; letter-spacing: .12em; }
.version-platform-status { position: absolute; z-index: 4; top: 12px; right: 12px; display: inline-flex; align-items: center; gap: 6px; padding: 7px 10px; border: 1px solid rgba(255, 255, 255, .48); border-radius: 999px; color: #5f6d82; background: rgba(248, 250, 255, .9); box-shadow: 0 8px 20px rgba(18, 35, 76, .12); backdrop-filter: blur(9px); font-size: 10px; font-weight: 900; white-space: nowrap; }
.version-platform-status::before { width: 6px; height: 6px; border-radius: 50%; background: #a7b1c0; content: ""; }
.version-platform-status--available { color: #3158aa; background: rgba(247, 250, 255, .94); }
.version-platform-status--available::before { background: var(--card-accent); box-shadow: 0 0 0 0 rgba(var(--card-rgb), .3); animation: status-pulse 2s ease-out infinite; }
.version-platform-card-head { position: relative; z-index: 1; display: grid; min-width: 0; align-items: start; margin-top: 24px; grid-template-columns: 1fr; }
.version-platform-card-head p { margin: 0 0 4px; color: var(--card-accent); font-size: 9px; font-weight: 900; letter-spacing: .08em; }
.version-platform-card-head h3 { margin: 0; overflow-wrap: anywhere; font-size: 22px; }
.version-platform-number { position: relative; z-index: 1; display: flex; align-items: flex-start; gap: 9px; margin-top: 38px; padding-top: 20px; border-top: 1px solid rgba(var(--card-rgb), .13); flex-direction: column; }
.version-platform-number span { color: var(--muted); font-size: 11px; font-weight: 700; }
.version-platform-number strong { font-size: 38px; letter-spacing: -.035em; }
.platform-detail { position: relative; z-index: 1; min-height: 3em; margin: 13px 0 20px; color: var(--muted); font-size: 11px; line-height: 1.5; overflow-wrap: anywhere; }
.version-platform-download { position: relative; z-index: 1; width: 100%; min-height: 52px; justify-content: flex-start; margin-top: auto; }
.version-platform-download--android { background: linear-gradient(135deg, #4f75e8, #5796e8); }
.version-platform-download--ios { background: linear-gradient(135deg, #566ad0, #788be4); }
.version-platform-download--windows { background: linear-gradient(135deg, #405bbc, #657bdb); }
.version-platform-download--linux { background: linear-gradient(135deg, #376cad, #5e91ce); }
.platform-button-arrow { margin-left: auto; font-size: 17px; transition: transform .2s ease; }
.version-platform-download:hover .platform-button-arrow { transform: translate(2px, -2px); }
.version-platform-download:disabled { cursor: not-allowed; border-color: #dfe5ef; color: #8894a7; background: #edf1f7; box-shadow: none; filter: none; opacity: 1; }
.version-platform-download:disabled::after { display: none; }

.toast { position: fixed; z-index: 120; right: 18px; bottom: 18px; max-width: min(420px, calc(100% - 36px)); padding: 13px 16px; border: 1px solid var(--line); border-radius: 8px; color: var(--text); background: var(--surface); box-shadow: var(--shadow); font-size: 13px; animation: toast-enter .18s ease both; }
.toast.error { border-color: rgba(190, 72, 92, .24); color: #a7465a; }

.global-click-effect { position: fixed; z-index: 2147483647; top: 0; left: 0; width: 0; height: 0; pointer-events: none; user-select: none; }
.global-click-effect > i { position: absolute; top: 0; left: 0; display: block; border-radius: 50%; pointer-events: none; }
.global-click-halo { width: 24px; height: 24px; background: radial-gradient(circle, rgba(126, 176, 255, .3), rgba(105, 132, 235, .11) 46%, transparent 72%); filter: blur(.4px); animation: global-click-halo 760ms ease-out both; }
.global-click-ring { width: 14px; height: 14px; border: 1.5px solid rgba(91, 137, 238, .8); box-shadow: 0 0 13px rgba(102, 150, 244, .22), inset 0 0 6px rgba(255, 255, 255, .46); animation: global-click-ring 740ms cubic-bezier(.16, .74, .24, 1) both; }
.global-click-ring--echo { width: 20px; height: 20px; border-width: 1px; border-color: rgba(137, 119, 229, .46); box-shadow: 0 0 9px rgba(117, 123, 228, .14); animation-duration: 850ms; animation-delay: 65ms; }
.global-click-core { width: 10px; height: 10px; background: radial-gradient(circle, rgba(255, 255, 255, .98) 0 17%, rgba(126, 177, 255, .88) 34%, rgba(102, 116, 226, .22) 58%, transparent 76%); box-shadow: 0 0 15px rgba(91, 137, 238, .42); animation: global-click-core 540ms ease-out both; }
.global-click-core::before, .global-click-core::after { position: absolute; top: 50%; left: 50%; width: 22px; height: 1px; border-radius: 999px; transform: translate(-50%, -50%); background: linear-gradient(90deg, transparent, rgba(220, 235, 255, .9), transparent); content: ""; }
.global-click-core::after { transform: translate(-50%, -50%) rotate(90deg); }
.global-click-ray { width: 18px; height: 1px; transform-origin: 0 50%; background: linear-gradient(90deg, rgba(194, 222, 255, .84), rgba(101, 143, 234, .08), transparent); box-shadow: 0 0 5px rgba(104, 151, 240, .24); animation: global-click-ray 610ms cubic-bezier(.18, .68, .24, 1) var(--click-ray-delay, 0ms) both; }
.global-click-particle { width: 4px; height: 4px; background: linear-gradient(145deg, #b9d7ff, #5f8ee9); box-shadow: 0 0 7px rgba(81, 130, 230, .35); animation: global-click-particle 740ms cubic-bezier(.15, .65, .25, 1) var(--click-delay, 0ms) both; }
.global-click-particle--1 { width: 3px; height: 3px; background: #d0e5ff; }
.global-click-particle--2 { width: 5px; height: 5px; border-radius: 1px !important; background: linear-gradient(145deg, #c8c5ff, #7088ea); --click-rotate: 135deg; }

@keyframes ticker-scroll { to { transform: translateX(-100%); } }
@keyframes ambient-float { to { transform: translate(50px, 35px) scale(1.08); } }
@keyframes topbar-enter { from { transform: translateY(-100%); opacity: 0; } }
@keyframes panel-sheen { 0%, 64% { left: -45%; } 86%, 100% { left: 125%; } }
@keyframes grid-drift { to { background-position: 32px 32px; } }
@keyframes orbit-spin { to { transform: translate(-50%, -50%) rotate(360deg); } }
@keyframes update-orbit { to { transform: rotate(360deg); } }
@keyframes status-pulse { 70% { box-shadow: 0 0 0 7px rgba(var(--card-rgb), 0); } 100% { box-shadow: 0 0 0 0 rgba(var(--card-rgb), 0); } }
@keyframes toast-enter { from { transform: translateY(8px); opacity: 0; } }
@keyframes global-click-halo { 0% { transform: translate(-50%, -50%) scale(.18); opacity: 0; } 18% { opacity: .68; } 100% { transform: translate(-50%, -50%) scale(3.4); opacity: 0; } }
@keyframes global-click-ring { 0% { transform: translate(-50%, -50%) scale(.3); opacity: 0; } 12% { opacity: .86; } 100% { transform: translate(-50%, -50%) scale(4.9); opacity: 0; } }
@keyframes global-click-core { 0% { transform: translate(-50%, -50%) scale(.3); opacity: 0; } 20% { transform: translate(-50%, -50%) scale(1); opacity: .96; } 100% { transform: translate(-50%, -50%) scale(2.7) rotate(25deg); opacity: 0; } }
@keyframes global-click-ray { 0% { transform: rotate(var(--click-angle)) translateX(2px) scaleX(.18); opacity: 0; } 22% { opacity: .72; } 100% { transform: rotate(var(--click-angle)) translateX(27px) scaleX(.08); opacity: 0; } }
@keyframes global-click-particle { 0% { transform: translate(-50%, -50%) rotate(0deg) scale(.2); opacity: 0; } 16% { opacity: .88; } 100% { transform: translate(calc(-50% + var(--click-x)), calc(-50% + var(--click-y))) rotate(var(--click-rotate, 70deg)) scale(.1); opacity: 0; } }

@media (max-width: 860px) {
  .topbar-inner { padding: 14px 0; flex-wrap: wrap; }
  .topbar-ticker { width: 100%; flex-basis: 100%; order: 3; }
  .hero { min-height: auto; grid-template-columns: 1fr; }
  .announcement-visual { min-height: 350px; }
  .version-platform-grid { grid-template-columns: 1fr; }
}

@media (max-width: 520px) {
  .page, .topbar-inner { width: min(100% - 20px, 1180px); }
  .topbar-download { margin-left: auto; }
  .hero { padding: 64px 0 48px; }
  h1 { font-size: 52px; }
  .inline-actions { align-items: stretch; flex-direction: column; }
  .inline-actions .button { width: 100%; }
  .announcement-visual { min-height: 410px; }
  .announcement-panel { inset: 14px; padding: 18px; }
  .panel-label-row { align-items: flex-start; flex-direction: column; gap: 0; }
  .panel-label-row > span { margin: -5px 0 12px; }
  .section-header { align-items: flex-start; flex-direction: column; }
  .version-platform-card { min-height: 540px; padding: 18px; }
  .version-platform-number { margin-top: 34px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}

/* r64 compact two-by-two client download cards. */
.announcement-panel .panel-label {
  margin-bottom: 16px;
  font-size: 18px;
  line-height: 1.2;
  letter-spacing: .08em;
}
.version-platform-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}
.version-platform-card {
  min-height: 0;
  padding: 18px;
  border-radius: 10px;
}
.version-platform-card::after {
  right: -138px;
  bottom: -190px;
  opacity: .58;
}
.version-platform-card:hover {
  transform: translateY(-3px);
}
.version-platform-card-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
  margin-top: 0;
}
.version-platform-card-head h3 {
  font-size: 19px;
}
.version-platform-status {
  position: relative;
  top: auto;
  right: auto;
  flex: 0 0 auto;
  padding: 6px 9px;
  border-color: rgba(var(--card-rgb), .18);
  color: #5f6d82;
  background: rgba(var(--card-rgb), .045);
  box-shadow: none;
  backdrop-filter: none;
}
.version-platform-status--available {
  color: #3158aa;
  background: rgba(var(--card-rgb), .08);
}
.version-platform-number {
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  margin-top: 18px;
  padding-top: 15px;
  flex-direction: row;
}
.version-platform-number strong {
  font-size: 22px;
  letter-spacing: -.02em;
}
.platform-detail {
  min-height: 0;
  margin: 8px 0 14px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.version-platform-download {
  min-height: 42px;
  margin-top: 0;
}
@media (max-width: 600px) {
  .version-platform-grid { grid-template-columns: 1fr; }
}
@media (max-width: 420px) {
  .version-platform-card-head { gap: 10px; }
  .version-platform-card-head h3 { font-size: 17px; }
  .version-platform-status { padding: 5px 7px; }
}