/* ==========================================================================
   兔兔薯语音克隆器 Pro — tts.qzent.ai
   Single stylesheet: design tokens, layout, components, animation.
   Palette follows the application's own "暖橙玻璃风" theme tokens
   (gui/theme.py): primary #fc8932 -> #fc6b42 -> #fc5351 on a #fff8f0 base.
   No external fonts, no external requests.
   ========================================================================== */

/* ---------- 1. Tokens ---------- */
:root {
  --brand: #fc6b42;
  --brand-2: #fc8932;
  --brand-3: #fc5351;
  --brand-deep: #e05436;
  --brand-soft: rgba(252, 137, 50, .10);
  --brand-softer: rgba(252, 137, 50, .055);
  --brand-line: rgba(252, 107, 66, .26);

  --bg: #fff8f0;
  --bg-alt: #fffdfa;
  --surface: #ffffff;
  --surface-2: #fff4ea;
  --glass: rgba(255, 255, 255, .74);
  --line: #f5e2d2;
  --line-strong: #eccfb8;

  --fg: #1f2233;
  --fg-2: #565a70;
  --fg-3: #8b8fa3;

  --ok: #2ecc71;
  --warn: #f39c12;
  --info: #42a5f5;

  --radius: 14px;
  --radius-lg: 20px;
  --radius-sm: 9px;

  --shadow-sm: 0 1px 2px rgba(90, 48, 22, .05), 0 2px 8px rgba(90, 48, 22, .05);
  --shadow: 0 10px 30px rgba(146, 68, 26, .10);
  --shadow-lg: 0 24px 64px rgba(146, 68, 26, .16);

  --wrap: 1160px;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
          "Hiragino Sans GB", "Microsoft YaHei UI", "Microsoft YaHei",
          "Source Han Sans SC", "Noto Sans CJK SC", Roboto, Arial, sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

/* ---------- 2. Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: 76px;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
}

body {
  margin: 0;
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.68;
  color: var(--fg);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4 { margin: 0; line-height: 1.24; font-weight: 700; letter-spacing: -.015em; }
p { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img, svg { display: block; max-width: 100%; }
a { color: var(--brand-deep); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
button { font: inherit; color: inherit; }
code, kbd, pre { font-family: var(--mono); }

:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 3px;
  border-radius: 6px;
}

.skip {
  position: absolute; left: -9999px; top: 0; z-index: 100;
  background: var(--brand); color: #fff; padding: 10px 16px; border-radius: 0 0 8px 0;
}
.skip:focus { left: 0; }

/* Sprite icons: geometry lives in assets/sprite.svg, so paint has to be stated
   here — fill/stroke do not cross the <use> shadow boundary. */
svg > use { fill: none; stroke: currentColor; }

/* ---------- 3. Layout helpers ---------- */
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px;
}

.section { padding: 84px 0; position: relative; }
.section--alt {
  background: var(--bg-alt);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.section__head { max-width: 720px; margin-bottom: 44px; }
.section__head--center { margin-left: auto; margin-right: auto; text-align: center; }

.eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 12px; font-weight: 700; letter-spacing: .14em; text-transform: uppercase;
  color: var(--brand-deep);
  padding: 5px 11px; border-radius: 999px;
  background: var(--brand-soft); border: 1px solid var(--brand-line);
  margin-bottom: 16px;
}
.eyebrow::before {
  content: ""; width: 6px; height: 6px; border-radius: 50%; background: currentColor;
}

h2.section__title { font-size: clamp(26px, 3.6vw, 38px); }
.section__sub { margin-top: 14px; color: var(--fg-2); font-size: 16.5px; }

/* ---------- 4. Header ---------- */
.hdr {
  position: sticky; top: 0; z-index: 50;
  /* Near-opaque: the page is dense with text, so a very translucent bar let
     content read through it while scrolling. */
  background: color-mix(in srgb, var(--bg) 94%, transparent);
  backdrop-filter: blur(14px) saturate(160%);
  border-bottom: 1px solid transparent;
  transition: border-color .25s ease, background-color .25s ease;
}
.hdr.is-stuck { border-bottom-color: var(--line); }
.hdr__in { display: flex; align-items: center; gap: 12px; height: 64px; }

.brand { display: flex; align-items: center; gap: 11px; color: var(--fg); font-weight: 700; }
.brand:hover { text-decoration: none; }
.brand img { width: 32px; height: 32px; border-radius: 9px; box-shadow: var(--shadow-sm); }
.brand__txt { display: flex; flex-direction: column; line-height: 1.15; }
.brand__name { font-size: 15.5px; letter-spacing: -.01em; }
.brand__sub { font-size: 11px; color: var(--fg-3); font-weight: 500; letter-spacing: .04em; }

.nav { margin-left: auto; display: flex; align-items: center; gap: 4px; }
.nav a {
  color: var(--fg-2); font-size: 14.5px; font-weight: 500;
  padding: 8px 12px; border-radius: 8px;
  transition: color .18s ease, background-color .18s ease;
}
.nav a:hover { color: var(--fg); background: var(--surface-2); text-decoration: none; }
.nav a.is-active { color: var(--brand-deep); background: var(--brand-soft); }

.hdr__act { display: flex; align-items: center; gap: 8px; margin-left: 6px; }

.icon-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 38px; height: 38px; border-radius: 10px;
  border: 1px solid var(--line); background: var(--surface);
  cursor: pointer; color: var(--fg-2);
  transition: transform .2s ease, border-color .2s ease, color .2s ease;
}
.icon-btn:hover { color: var(--brand-deep); border-color: var(--brand-line); transform: translateY(-1px); }
.icon-btn svg { width: 19px; height: 19px; display: block; }

.burger { display: none; }

@media (max-width: 900px) {
  .nav {
    position: fixed; inset: 64px 0 auto 0;
    flex-direction: column; align-items: stretch; gap: 2px;
    background: var(--bg-alt); border-bottom: 1px solid var(--line);
    padding: 10px 20px 18px; box-shadow: var(--shadow);
    transform: translateY(-12px); opacity: 0; pointer-events: none;
    transition: opacity .2s ease, transform .2s ease;
  }
  .nav.is-open { transform: none; opacity: 1; pointer-events: auto; }
  .nav a { padding: 12px; font-size: 16px; }
  .burger { display: inline-flex; }
}

@media (max-width: 560px) {
  .brand img { width: 26px; height: 26px; border-radius: 8px; }
  .brand__name { font-size: 14px; white-space: nowrap; }
  .brand__sub { display: none; }
  .hdr__in { gap: 6px; }
  .brand { gap: 8px; }
  .hdr__act { gap: 5px; margin-left: 2px; }
  .hdr__act .btn--sm { padding: 8px 11px; font-size: 13.5px; }
  .icon-btn { width: 36px; height: 36px; }
  .hero { padding: 44px 0 60px; }
}

/* ---------- 5. Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 9px;
  padding: 12px 20px; border-radius: 11px;
  border: 1px solid transparent; cursor: pointer;
  font-size: 15px; font-weight: 600; letter-spacing: -.005em;
  text-decoration: none; white-space: nowrap;
  transition: transform .18s ease, box-shadow .22s ease, background-color .2s ease,
              border-color .2s ease, color .2s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-2px); }
.btn:active { transform: translateY(0); }
.btn svg { width: 19px; height: 19px; flex: none; }

.btn--primary {
  background: linear-gradient(135deg, var(--brand-2), var(--brand) 52%, var(--brand-3));
  color: #fff; box-shadow: 0 6px 18px rgba(252, 107, 66, .30);
}
.btn--primary:hover { box-shadow: 0 12px 28px rgba(252, 107, 66, .40); }

.btn--ghost {
  background: var(--surface); color: var(--fg);
  border-color: var(--line-strong);
}
.btn--ghost:hover { border-color: var(--brand-line); color: var(--brand-deep); }

.btn--sm { padding: 9px 14px; font-size: 14px; border-radius: 9px; }
.btn--block { width: 100%; }

/* ---------- 6. Hero ---------- */
.hero {
  position: relative;
  padding: 76px 0 84px;
  overflow: hidden;
  background:
    radial-gradient(900px 460px at 84% -12%, rgba(252, 137, 50, .18), transparent 62%),
    radial-gradient(760px 430px at 2% 6%, rgba(252, 83, 81, .11), transparent 60%);
}
.hero__grid-bg {
  position: absolute; inset: 0; z-index: 0; opacity: .55; pointer-events: none;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(660px 340px at 52% 22%, #000 18%, transparent 78%);
  -webkit-mask-image: radial-gradient(660px 340px at 52% 22%, #000 18%, transparent 78%);
  animation: gridDrift 26s linear infinite;
}
@keyframes gridDrift {
  from { background-position: 0 0, 0 0; }
  to { background-position: 56px 56px, 56px 56px; }
}

.hero__in {
  position: relative; z-index: 1;
  display: grid; grid-template-columns: minmax(0, 1.02fr) minmax(0, .98fr);
  gap: 54px; align-items: center;
}
@media (max-width: 980px) {
  .hero__in { grid-template-columns: 1fr; gap: 46px; }
}

.hero__badge {
  display: inline-flex; align-items: center; gap: 9px;
  padding: 5px 12px 5px 6px; border-radius: 999px;
  background: var(--glass); border: 1px solid var(--line);
  font-size: 12.5px; font-weight: 600; color: var(--fg-2);
  box-shadow: var(--shadow-sm); margin-bottom: 22px;
}
.hero__badge b {
  background: linear-gradient(135deg, var(--brand-2), var(--brand-3));
  color: #fff; padding: 3px 9px; border-radius: 999px;
  font-size: 11.5px; letter-spacing: .04em;
}

.hero h1 { font-size: clamp(32px, 5vw, 52px); letter-spacing: -.03em; }
.hero h1 .grad {
  background: linear-gradient(118deg, var(--brand-2), var(--brand) 48%, var(--brand-3));
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}
.hero__cn {
  display: block; margin-top: 10px;
  font-size: clamp(18px, 2.4vw, 24px); color: var(--fg-2);
  font-weight: 600; letter-spacing: 0;
}
.hero__lead { margin-top: 20px; font-size: 17px; color: var(--fg-2); max-width: 540px; }

.hero__cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }

.hero__meta {
  display: flex; flex-wrap: wrap; gap: 8px 22px;
  margin-top: 24px; font-size: 13.5px; color: var(--fg-3);
}
.hero__meta span { display: inline-flex; align-items: center; gap: 7px; }
.hero__meta svg { width: 16px; height: 16px; flex: none; color: var(--brand); }

/* Floating decorative music-note marks */
.float-tags { position: absolute; inset: 0; z-index: 0; pointer-events: none; }
.float-tag {
  position: absolute; width: 46px; height: 46px; opacity: 0;
  animation: floatTag 15s ease-in-out infinite;
}
.float-tag svg { width: 100%; height: 100%; }
@keyframes floatTag {
  0%, 100% { transform: translateY(0) rotate(-6deg); opacity: .12; }
  50% { transform: translateY(-22px) rotate(6deg); opacity: .26; }
}

/* ---------- 7. Hero demo: replica of the app window ---------- */
.demo {
  --ink: #1f2233;
  --ink-2: rgba(31, 34, 51, .72);
  --ink-3: rgba(31, 34, 51, .48);
  --card-border: rgba(252, 137, 50, .30);
  --sunken: #fff4ea;
  --note: #fff7ee;

  position: relative;
  display: flex; flex-direction: column;
  min-height: 548px;
  border: 1px solid rgba(252, 137, 50, .28);
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, #fff8f0, #fff3e8 52%, #fff0f0);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
  isolation: isolate;
  transition: transform .5s cubic-bezier(.2, .8, .25, 1);
}
.demo:hover { transform: translateY(-4px); }

.demo__bar {
  position: relative; z-index: 1;
  display: flex; align-items: center; gap: 7px;
  padding: 8px 12px;
  background: rgba(255, 255, 255, .6);
  border-bottom: 1px solid var(--card-border);
}
.demo__dot { width: 5px; height: 5px; border-radius: 50%; background: var(--ink-3); flex: none; }
.demo__path {
  margin-left: 8px; font-family: var(--mono); font-size: 11px;
  letter-spacing: .06em; color: var(--ink-3);
}
.demo__ver {
  margin-left: auto; font-family: var(--mono); font-size: 10.5px;
  padding: 2px 8px; border-radius: 999px;
  color: var(--brand-deep); background: var(--brand-soft); border: 1px solid var(--brand-line);
}

.demo__body {
  position: relative; z-index: 1;
  display: grid; grid-template-columns: 152px minmax(0, 1fr);
  flex: 1; min-height: 0;
}

/* sidebar: the app's signature orange gradient rail */
.demo__side {
  display: flex; flex-direction: column; gap: 4px;
  padding: 13px 11px;
  background: linear-gradient(180deg, var(--brand-2), var(--brand-3));
  color: rgba(255, 255, 255, .92);
}
.demo__side-brand {
  display: flex; align-items: center; gap: 8px;
  padding: 4px 4px 13px; margin-bottom: 4px;
  border-bottom: 1px solid rgba(255, 255, 255, .28);
  font-size: 11px; font-weight: 700; line-height: 1.3; white-space: nowrap;
}
.demo__side-brand svg { width: 19px; height: 19px; flex: none; }
.demo__side-item {
  display: flex; align-items: center; gap: 8px;
  padding: 7px 9px; border-radius: 9px;
  font-size: 11.5px; font-weight: 600; white-space: nowrap;
  transition: background-color .25s ease, color .25s ease;
}
.demo__side-item svg { width: 15px; height: 15px; flex: none; }
.demo__side-item.is-on {
  background: rgba(255, 255, 255, .93); color: var(--ink);
  box-shadow: 0 4px 12px rgba(120, 50, 10, .16);
}
.demo__side-foot {
  margin-top: auto; display: flex; align-items: center; gap: 7px;
  padding: 7px 9px; border-radius: 9px;
  background: rgba(255, 255, 255, .18);
  font-size: 11px; font-weight: 600;
}
.demo__side-foot i {
  width: 7px; height: 7px; border-radius: 50%; background: #b8f0c9; flex: none;
  animation: dotPulse 2s ease-in-out infinite;
}
@keyframes dotPulse { 0%, 100% { opacity: 1; } 50% { opacity: .35; } }

/* main pane */
.demo__main {
  display: flex; flex-direction: column; gap: 10px;
  padding: 13px 14px; min-width: 0;
}

.demo__head { display: flex; align-items: center; gap: 8px; }
.demo__title { font-size: 13px; font-weight: 700; }
.demo__badge {
  font-family: var(--mono); font-size: 10px; padding: 2px 8px; border-radius: 999px;
  background: var(--brand-soft); border: 1px solid var(--brand-line); color: var(--brand-deep);
}
.demo__auth {
  margin-left: auto; display: inline-flex; align-items: center; gap: 5px;
  font-size: 11px; font-weight: 700; color: var(--ok);
}
.demo__auth svg { width: 14px; height: 14px; }

/* audio dropzone + waveform */
.demo__audio {
  position: relative;
  padding: 10px 11px 8px;
  border: 1px solid var(--card-border); border-radius: var(--radius);
  background: rgba(255, 255, 255, .78);
}
.demo__label {
  display: flex; align-items: center; gap: 6px;
  font-size: 11px; font-weight: 700; color: var(--ink-2);
}
.demo__label svg { width: 13px; height: 13px; color: var(--brand); }
.demo__label em {
  margin-left: auto; font-style: normal; font-family: var(--mono);
  font-size: 10.5px; color: var(--ink-3);
}
.demo__wave {
  position: relative; margin-top: 7px;
  height: 74px; border-radius: 9px; overflow: hidden;
  background: var(--sunken); border: 1px solid var(--card-border);
}
.demo__wave img { width: 100%; height: 100%; }
.demo__wave-cap {
  position: absolute; right: 8px; top: 6px;
  padding: 1px 7px; border-radius: 999px;
  background: rgba(255, 255, 255, .86);
  font-family: var(--mono); font-size: 10px; font-weight: 700;
  color: var(--brand-deep); pointer-events: none;
}
.demo__cursor {
  position: absolute; top: 6px; bottom: 6px; width: 2px;
  background: var(--brand-3); border-radius: 2px;
  box-shadow: 0 0 8px rgba(252, 83, 81, .55);
  animation: curSlide 5.2s ease-in-out infinite;
}
@keyframes curSlide {
  0%, 100% { left: 12%; }
  50% { left: 76%; }
}

/* text + parameters */
.demo__text {
  padding: 10px 11px;
  border: 1px solid var(--card-border); border-radius: var(--radius);
  background: rgba(255, 255, 255, .78);
}
.demo__text p {
  margin-top: 7px; font-size: 12px; line-height: 1.6; color: var(--ink-2);
}
.demo__text .caret {
  display: inline-block; width: 2px; height: 12px; margin-left: 2px;
  background: var(--brand-2); vertical-align: -2px;
  animation: caretBlink 1.05s step-end infinite;
}
@keyframes caretBlink { 0%, 100% { opacity: 1; } 50% { opacity: 0; } }

.demo__params { display: flex; flex-wrap: wrap; gap: 6px; }
.demo__chip {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 9px; border-radius: 999px;
  background: rgba(255, 255, 255, .8);
  border: 1px solid var(--card-border);
  font-size: 11px; font-weight: 600; color: var(--ink-2);
}
.demo__chip b { color: var(--brand-deep); font-weight: 700; }
.demo__chip--on {
  background: linear-gradient(135deg, var(--brand-2), var(--brand-3));
  border-color: transparent; color: #fff;
}
.demo__chip--on b { color: #fff; }

.demo__bar-wrap { margin-top: auto; display: flex; align-items: center; gap: 10px; }
.demo__prog {
  flex: 1; height: 8px; border-radius: 999px; overflow: hidden;
  background: rgba(255, 255, 255, .82); border: 1px solid var(--card-border);
}
.demo__prog i {
  display: block; height: 100%; width: 0;
  background: linear-gradient(90deg, var(--brand-2), var(--brand), var(--brand-3));
  background-size: 200% 100%;
  animation: hueSlide 3s linear infinite, fillUp 5.2s ease-in-out infinite;
}
@keyframes hueSlide { to { background-position: 200% 0; } }
@keyframes fillUp {
  0% { width: 6%; }
  55% { width: 82%; }
  70% { width: 100%; }
  100% { width: 100%; }
}
.demo__pct { font-family: var(--mono); font-size: 11px; font-weight: 700; color: var(--brand-deep); flex: none; }

.demo__rows {
  display: grid; gap: 6px;
  max-height: 118px; overflow: hidden;
  /* the queue runs past the frame on purpose: fade the last row instead of
     cutting it with a hard edge */
  mask-image: linear-gradient(180deg, #000 72%, transparent 100%);
  -webkit-mask-image: linear-gradient(180deg, #000 72%, transparent 100%);
}
.demo__row {
  display: grid; grid-template-columns: minmax(0, 1fr) 72px 70px;
  gap: 8px; align-items: center;
  padding: 7px 10px; border-radius: 11px;
  background: rgba(255, 255, 255, .78); border: 1px solid var(--card-border);
  font-size: 11.5px;
}
.demo__row b {
  font-weight: 600; color: var(--ink-2); overflow: hidden;
  text-overflow: ellipsis; white-space: nowrap;
}
.demo__row time { font-family: var(--mono); font-size: 10.5px; color: var(--ink-3); white-space: nowrap; }
.demo__row span {
  justify-self: end; font-family: var(--mono); font-size: 10px;
  padding: 2px 7px; border-radius: 999px;
  background: var(--sunken); color: var(--ink-2); white-space: nowrap;
}
.demo__row span.is-ok { color: #157a52; background: rgba(46, 204, 113, .14); }

@media (max-width: 1080px) {
  .demo__body { grid-template-columns: 126px minmax(0, 1fr); }
}
@media (max-width: 760px) {
  .demo { min-height: 0; }
  .demo__body { grid-template-columns: 1fr; }
  .demo__side {
    flex-direction: row; flex-wrap: wrap; gap: 6px;
    padding: 10px;
  }
  .demo__side-brand { border-bottom: 0; padding: 0 6px 0 0; margin: 0; }
  .demo__side-brand span { display: none; }
  .demo__side-foot { display: none; }
  .demo__side-item { padding: 6px 9px; }
  .demo__rows { display: none; }
}

/* ---------- 8. Feature grid ---------- */
.grid { display: grid; gap: 18px; }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(276px, 1fr)); }

.card {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  overflow: hidden;
  transition: transform .22s ease, border-color .22s ease, box-shadow .22s ease;
}
.card::after {
  content: ""; position: absolute; inset: 0 0 auto 0; height: 2px;
  background: linear-gradient(90deg, var(--brand-2), var(--brand-3));
  transform: scaleX(0); transform-origin: left;
  transition: transform .35s ease;
}
.card:hover { transform: translateY(-4px); border-color: var(--brand-line); box-shadow: var(--shadow); }
.card:hover::after { transform: scaleX(1); }
.card__ico {
  width: 40px; height: 40px; border-radius: 11px;
  display: grid; place-items: center; margin-bottom: 15px;
  background: var(--brand-soft); color: var(--brand-deep);
  border: 1px solid var(--brand-line);
}
.card__ico svg { width: 21px; height: 21px; }
.card h3 { font-size: 16.5px; }
.card p { margin-top: 8px; font-size: 14.5px; color: var(--fg-2); }
.card__en {
  display: block; margin-top: 5px;
  font-size: 11.5px; font-weight: 600; letter-spacing: .07em;
  text-transform: uppercase; color: var(--fg-3);
}

/* ---------- 9. Pipeline diagram ---------- */
.pipe-figure {
  margin: 0 0 26px; padding: 18px;
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius-lg); box-shadow: var(--shadow-sm);
  overflow-x: auto;
}
.pipe-figure img { width: 100%; min-width: 720px; height: auto; }

.pipe {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(196px, 1fr));
  gap: 14px; margin-bottom: 26px;
}
.step {
  position: relative;
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 18px 18px 20px;
  transition: border-color .3s ease, box-shadow .3s ease, transform .3s ease;
}
.step__n {
  display: flex; align-items: center; gap: 8px; margin-bottom: 10px;
  font-family: var(--mono); font-size: 11.5px; color: var(--fg-3);
}
.step__n i {
  width: 7px; height: 7px; border-radius: 50%; background: var(--line-strong);
  transition: background-color .3s ease, box-shadow .3s ease;
}
.step h4 { font-size: 15px; }
.step p { margin-top: 7px; font-size: 13.5px; color: var(--fg-2); }
.step__tech {
  display: inline-block; margin-top: 11px;
  font-family: var(--mono); font-size: 11.5px;
  padding: 3px 8px; border-radius: 6px;
  background: var(--surface-2); color: var(--fg-2);
}
.step.is-active { border-color: var(--brand-line); box-shadow: 0 0 0 3px var(--brand-soft); transform: translateY(-3px); }
.step.is-active .step__n i { background: var(--brand); box-shadow: 0 0 0 4px var(--brand-soft); }
.step.is-done .step__n i { background: var(--ok); }

.pipe__bar {
  height: 6px; border-radius: 3px; overflow: hidden;
  background: var(--surface-2); border: 1px solid var(--line);
}
.pipe__bar i {
  display: block; height: 100%; width: 0;
  background: linear-gradient(90deg, var(--brand-2), var(--brand), var(--brand-3));
  background-size: 200% 100%;
  animation: hueSlide 3s linear infinite;
  transition: width .5s cubic-bezier(.3, .9, .3, 1);
}
.pipe__status {
  display: flex; justify-content: space-between; align-items: center;
  margin-top: 10px; font-size: 12.5px; color: var(--fg-3); font-family: var(--mono);
}

.facts {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 14px; margin-top: 26px;
}
.fact {
  border: 1px dashed var(--line-strong); border-radius: var(--radius);
  padding: 16px 18px; background: var(--surface-2);
}
.fact b { display: block; font-size: 14.5px; }
.fact span { font-size: 13.5px; color: var(--fg-2); }

/* ---------- 10. Use cases ---------- */
.uses { display: grid; grid-template-columns: repeat(auto-fit, minmax(232px, 1fr)); gap: 14px; }
.use {
  display: flex; align-items: center; gap: 12px;
  padding: 15px 17px; border-radius: var(--radius);
  background: var(--surface); border: 1px solid var(--line);
  font-size: 14.5px; font-weight: 600;
  transition: border-color .2s ease, transform .2s ease;
}
.use:hover { border-color: var(--brand-line); transform: translateY(-3px); }
.use svg { width: 20px; height: 20px; flex: none; color: var(--brand); }

/* ---------- 11. Download ---------- */
.dl { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr); gap: 22px; align-items: start; }
@media (max-width: 900px) { .dl { grid-template-columns: 1fr; } }

.dl__main {
  position: relative; overflow: hidden;
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius-lg); padding: 28px;
  box-shadow: var(--shadow);
}
.dl__main::before {
  content: ""; position: absolute; inset: -60% -20% auto auto; width: 320px; height: 320px;
  background: radial-gradient(circle, rgba(252, 137, 50, .16), transparent 66%);
  pointer-events: none;
}
.dl__ver { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; }
.dl__ver strong { font-size: 25px; letter-spacing: -.02em; }
.dl__ver em { font-style: normal; font-size: 13px; color: var(--fg-3); font-family: var(--mono); }

.specs { display: grid; margin: 20px 0 22px; border-top: 1px solid var(--line); }
.specs li {
  display: flex; justify-content: space-between; gap: 16px;
  padding: 10px 0; border-bottom: 1px solid var(--line); font-size: 14px;
}
.specs li span:first-child { color: var(--fg-3); }
.specs li span:last-child { font-family: var(--mono); font-size: 13px; text-align: right; }

.urlbox {
  display: flex; align-items: center; gap: 8px;
  margin-top: 16px; padding: 8px 8px 8px 14px;
  background: var(--surface-2); border: 1px dashed var(--line-strong);
  border-radius: 10px;
}
.urlbox code {
  flex: 1; min-width: 0; font-size: 12.5px; color: var(--fg-2);
  overflow-x: auto; white-space: nowrap; scrollbar-width: none;
}
.urlbox code::-webkit-scrollbar { display: none; }
.urlbox .icon-btn { width: 32px; height: 32px; border-radius: 8px; }
.urlbox .icon-btn svg { width: 16px; height: 16px; }

.note {
  display: flex; gap: 11px; align-items: flex-start;
  margin-top: 18px; padding: 13px 15px;
  border-radius: 11px; font-size: 13.5px; color: var(--fg-2);
  background: rgba(243, 156, 18, .10);
  border: 1px solid rgba(243, 156, 18, .32);
}
.note svg { width: 17px; height: 17px; flex: none; color: var(--warn); margin-top: 2px; }
.note code {
  font-size: 12.5px; padding: 1px 6px; border-radius: 5px;
  background: rgba(255, 255, 255, .7); border: 1px solid var(--line);
}

.dl__side { display: grid; gap: 14px; }

.drive {
  display: flex; align-items: flex-start; gap: 16px;
  padding: 18px; background: var(--surface);
  border: 1px solid var(--line); border-radius: var(--radius-lg);
  color: inherit;
  transition: border-color .2s ease, box-shadow .2s ease, transform .2s ease;
}
.drive:hover { text-decoration: none; border-color: var(--brand-line); box-shadow: var(--shadow); transform: translateY(-3px); }
.drive__ico {
  width: 42px; height: 42px; flex: none; border-radius: 12px;
  display: grid; place-items: center; color: #fff;
  background: linear-gradient(135deg, var(--brand-2), var(--brand-3));
  box-shadow: 0 6px 16px rgba(252, 107, 66, .3);
}
.drive__ico svg { width: 22px; height: 22px; }
.drive__body { min-width: 0; }
.drive__body b { display: flex; align-items: center; gap: 9px; flex-wrap: wrap; font-size: 17px; }
.drive__body b em {
  font-style: normal; font-size: 11.5px; font-weight: 600;
  padding: 2px 8px; border-radius: 999px;
  color: var(--brand-deep); background: var(--brand-soft); border: 1px solid var(--brand-line);
}
.drive__body p { font-size: 13.5px; color: var(--fg-2); margin-top: 3px; }
.drive__meta { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 10px; }
.drive__go { margin-left: auto; align-self: center; color: var(--fg-3); flex: none; }
.drive__go svg { width: 17px; height: 17px; }

.pill {
  font-size: 11.5px; font-family: var(--mono); padding: 3px 9px; border-radius: 999px;
  background: var(--surface-2); border: 1px solid var(--line); color: var(--fg-2);
}
.pill--ok {
  color: #1f9d63; border-color: rgba(46, 204, 113, .4); background: rgba(46, 204, 113, .12);
}

.pw {
  display: inline-flex; align-items: center; gap: 7px;
  margin-top: 10px; padding: 3px 4px 3px 10px;
  border: 1px dashed var(--line-strong); border-radius: 9px;
  background: var(--surface-2); font-size: 12.5px;
}
.pw > span { color: var(--fg-3); }
.pw > code {
  font-family: var(--mono); font-size: 13px; font-weight: 700;
  letter-spacing: .06em; color: var(--fg);
}
.pw .icon-btn { width: 26px; height: 26px; border-radius: 7px; }
.pw .icon-btn svg { width: 14px; height: 14px; }

.qr {
  display: grid; place-items: center; gap: 12px;
  padding: 22px; background: var(--surface);
  border: 1px solid var(--line); border-radius: var(--radius-lg);
  text-align: center;
}
.qr img {
  width: 168px; height: 168px; border-radius: 12px;
  border: 1px solid var(--line); background: #fff; padding: 6px;
}
.qr b { font-size: 14.5px; }
.qr p { font-size: 13px; color: var(--fg-2); }

/* ---------- 12. Steps ---------- */
.steps { display: grid; gap: 14px; }
.stepper {
  display: grid; grid-template-columns: 40px minmax(0, 1fr); gap: 16px;
  padding: 18px 20px; background: var(--surface);
  border: 1px solid var(--line); border-radius: var(--radius);
  transition: border-color .2s ease, transform .2s ease;
}
.stepper:hover { border-color: var(--brand-line); transform: translateX(4px); }
.stepper__n {
  width: 40px; height: 40px; border-radius: 11px; display: grid; place-items: center;
  font-family: var(--mono); font-size: 15px; font-weight: 700; color: var(--brand-deep);
  background: var(--brand-soft); border: 1px solid var(--brand-line);
}
.stepper b { font-size: 15.5px; }
.stepper p { font-size: 14px; color: var(--fg-2); margin-top: 5px; }
.stepper code, .req code {
  font-size: 12.5px; padding: 1px 6px; border-radius: 5px;
  background: var(--surface-2); border: 1px solid var(--line);
}

.req { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 18px; }
.req__col { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; }
.req__col h4 { display: flex; align-items: center; gap: 9px; font-size: 15px; margin-bottom: 14px; }
.req__col h4 svg { width: 18px; height: 18px; color: var(--brand); flex: none; }
.req__col li {
  display: flex; justify-content: space-between; gap: 12px;
  font-size: 13.5px; padding: 7px 0; border-bottom: 1px dashed var(--line);
}
.req__col li:last-child { border-bottom: 0; }
.req__col li span:first-child { color: var(--fg-3); }
.req__col li span:last-child { font-family: var(--mono); font-size: 12.5px; text-align: right; }

/* ---------- 13. Tech stack ---------- */
.techgrid { display: grid; grid-template-columns: repeat(auto-fit, minmax(216px, 1fr)); gap: 12px; }
.tech {
  display: flex; flex-direction: column; gap: 3px;
  padding: 16px 18px; border-radius: var(--radius);
  background: var(--surface); border: 1px solid var(--line);
  transition: border-color .2s ease, transform .2s ease, box-shadow .2s ease;
}
.tech:hover { border-color: var(--brand-line); transform: translateY(-3px); box-shadow: var(--shadow-sm); }
.tech b { font-family: var(--mono); font-size: 14px; letter-spacing: -.01em; }
.tech span { font-size: 13px; color: var(--fg-3); }

/* ---------- 14. FAQ ---------- */
.faq { display: grid; gap: 10px; }
.faq details {
  background: var(--surface); border: 1px solid var(--line);
  border-radius: var(--radius); overflow: hidden;
  transition: border-color .2s ease;
}
.faq details[open] { border-color: var(--brand-line); }
.faq summary {
  display: flex; align-items: center; gap: 12px; list-style: none;
  cursor: pointer; padding: 16px 20px; font-size: 15.5px; font-weight: 600;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: ""; margin-left: auto; width: 9px; height: 9px; flex: none;
  border-right: 2px solid var(--fg-3); border-bottom: 2px solid var(--fg-3);
  transform: rotate(45deg) translateY(-2px);
  transition: transform .25s ease;
}
.faq details[open] summary::after { transform: rotate(225deg) translateY(-2px); }
.faq p { padding: 0 20px 18px; font-size: 14.5px; color: var(--fg-2); }
.faq code {
  font-size: 12.5px; padding: 1px 6px; border-radius: 5px;
  background: var(--surface-2); border: 1px solid var(--line);
}

/* ---------- 15. Footer ---------- */
.ftr {
  background: var(--bg-alt); border-top: 1px solid var(--line);
  padding: 54px 0 30px;
}
.ftr__grid { display: grid; grid-template-columns: minmax(0, 1.4fr) repeat(3, minmax(0, 1fr)); gap: 34px; }
@media (max-width: 820px) { .ftr__grid { grid-template-columns: 1fr 1fr; gap: 26px; } }
@media (max-width: 520px) { .ftr__grid { grid-template-columns: 1fr; } }
.ftr h4 {
  font-size: 13px; letter-spacing: .1em; text-transform: uppercase;
  color: var(--fg-3); margin-bottom: 14px;
}
.ftr li + li { margin-top: 9px; }
.ftr a { color: var(--fg-2); font-size: 14px; }
.ftr a:hover { color: var(--brand-deep); }
.ftr__about p { font-size: 13.5px; color: var(--fg-2); margin-top: 12px; max-width: 330px; }
.ftr__bot {
  margin-top: 40px; padding-top: 20px; border-top: 1px solid var(--line);
  display: flex; flex-wrap: wrap; gap: 10px 20px; justify-content: space-between;
  font-size: 13px; color: var(--fg-3);
}

/* ---------- 16. Reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s ease, transform .6s cubic-bezier(.2, .8, .25, 1); }
.reveal.is-in { opacity: 1; transform: none; }
.reveal--d1 { transition-delay: .06s; }
.reveal--d2 { transition-delay: .12s; }
.reveal--d3 { transition-delay: .18s; }

/* ---------- 17. Back to top ---------- */
.totop {
  position: fixed; right: 22px; bottom: 22px; z-index: 40;
  width: 44px; height: 44px; border-radius: 50%;
  display: grid; place-items: center; cursor: pointer;
  background: var(--surface); color: var(--fg-2);
  border: 1px solid var(--line); box-shadow: var(--shadow);
  opacity: 0; transform: translateY(12px) scale(.9); pointer-events: none;
  transition: all .25s ease;
}
.totop.is-on { opacity: 1; transform: none; pointer-events: auto; }
.totop:hover { color: var(--brand-deep); border-color: var(--brand-line); }
.totop svg { width: 20px; height: 20px; }

/* ---------- 18. Toast ---------- */
.toast {
  position: fixed; left: 50%; bottom: 28px; z-index: 60;
  transform: translate(-50%, 20px);
  background: var(--fg); color: var(--bg);
  padding: 10px 18px; border-radius: 999px;
  font-size: 13.5px; font-weight: 600;
  box-shadow: var(--shadow-lg); opacity: 0; pointer-events: none;
  transition: opacity .22s ease, transform .22s ease;
}
.toast.is-on { opacity: 1; transform: translate(-50%, 0); }

/* ---------- 19. Print ---------- */
@media print {
  .hdr, .totop, .toast, .hero__grid-bg, .float-tags { display: none !important; }
  body { background: #fff; color: #000; }
  .card, .step, .drive, .qr, .dl__main, .demo { box-shadow: none; }
}