/* ────────────────────────────────────────────────
 * EchoLing AI website — editorial paper aesthetic.
 * Shares the desktop app's design language: warm stone
 * neutrals + brand blue, serif display headlines for a
 * "professional interpreter" editorial feel.
 * ──────────────────────────────────────────────── */

:root {
  --paper:        #FAF9F7;
  --paper-deep:   #F3F1ED;
  --ink:          #1C1917;
  --ink-strong:   #0C0A09;
  --ink-muted:    #57534E;
  --ink-faint:    #A8A29E;
  --line:         #E7E5E4;
  --line-subtle:  #EFEDEA;
  --blue:         #2563EB;
  --blue-bright:  #3B82F6;
  --blue-deep:    #1E40AF;
  --blue-faint:   rgba(59, 130, 246, 0.08);
  --blue-line:    rgba(59, 130, 246, 0.28);
  --teal:         #0D9488;
  --teal-faint:   rgba(13, 148, 136, 0.09);

  --serif: "Noto Serif", "Noto Serif JP", Georgia, serif;
  --sans:  "Noto Sans", "Noto Sans JP", "Segoe UI", sans-serif;
  --mono:  "JetBrains Mono", "Cascadia Mono", Consolas, monospace;

  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --maxw: 1080px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--sans);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  /* 纸感颗粒 — 全页极淡噪点 */
  position: relative;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  opacity: 0.03;
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='180' height='180'><filter id='g'><feTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/></filter><rect width='180' height='180' filter='url(%23g)'/></svg>");
}

::selection { background: var(--blue-faint); color: var(--ink-strong); }

/* ── 顶栏 ── */
.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  gap: 32px;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 18px 28px;
  background: color-mix(in srgb, var(--paper) 86%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink-strong); }
.brand-name { font-weight: 700; font-size: 16px; letter-spacing: 0.01em; }

/* 波形品牌徽标 — 与应用同款 */
.brand-mark {
  width: 30px; height: 30px;
  border-radius: 9px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 2px;
  background: linear-gradient(150deg, #4C8DF7 0%, #2563EB 55%, #1E40AF 100%);
  box-shadow: 0 4px 12px -4px rgba(30, 64, 175, 0.5), inset 0 1px 0 rgba(255,255,255,0.28);
  flex-shrink: 0;
}
.brand-mark i {
  width: 2.5px; border-radius: 99px; background: rgba(255,255,255,0.95);
  animation: wave 1.4s var(--ease) infinite;
}
.brand-mark i:nth-child(1) { height: 6px;  animation-delay: 0s; }
.brand-mark i:nth-child(2) { height: 10px; animation-delay: .12s; }
.brand-mark i:nth-child(3) { height: 14px; animation-delay: .24s; }
.brand-mark i:nth-child(4) { height: 10px; animation-delay: .36s; }
.brand-mark i:nth-child(5) { height: 6px;  animation-delay: .48s; }
.brand-mark.sm { width: 22px; height: 22px; border-radius: 7px; }
.brand-mark.sm i { transform: scale(0.75); }
@keyframes wave { 0%,100% { transform: scaleY(0.5); } 50% { transform: scaleY(1); } }

.topnav { display: flex; gap: 26px; margin-left: auto; }
.topnav a {
  font-size: 13.5px; color: var(--ink-muted); text-decoration: none;
  transition: color .18s var(--ease);
}
.topnav a:hover { color: var(--ink-strong); }

/* ── 按钮 ── */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  font-family: var(--sans); font-weight: 600; text-decoration: none;
  border-radius: 11px; cursor: pointer; border: none;
  transition: transform .15s var(--ease), box-shadow .2s var(--ease);
}
.btn-primary {
  position: relative;
  height: 48px; padding: 0 26px; font-size: 15px;
  color: #fff;
  background: linear-gradient(180deg, #3B82F6 0%, #2563EB 100%);
  box-shadow: 0 6px 18px -6px rgba(37, 99, 235, 0.5), inset 0 1px 0 rgba(255,255,255,0.25);
  overflow: hidden;
}
.btn-primary::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(180deg, #2F74F0 0%, #1D4ED8 100%);
  opacity: 0; transition: opacity .18s var(--ease);
}
.btn-primary:hover::after { opacity: 1; }
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 10px 26px -8px rgba(37,99,235,0.6), inset 0 1px 0 rgba(255,255,255,0.25); }
.btn-primary > * { position: relative; z-index: 1; }
.btn-sm { height: 36px; padding: 0 16px; font-size: 13px; border-radius: 9px; }
.btn-lg { height: 54px; padding: 0 34px; font-size: 16px; }
.btn-block { width: 100%; }
.btn-ghost {
  height: 48px; padding: 0 26px; font-size: 15px;
  color: var(--blue-deep);
  background: #fff;
  border: 1px solid var(--line);
}
.btn-ghost:hover { transform: translateY(-1px); border-color: var(--blue); color: var(--blue); }
/* When a plan stacks two CTAs, the second sits closer to the first */
.plan-cta + .plan-cta { margin-top: 10px; }
.btn[disabled], .btn.is-disabled {
  cursor: not-allowed; opacity: .6; transform: none; box-shadow: none;
}

/* ── Hero ── */
.hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 48px;
  align-items: center;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 72px 28px 110px;
}
/* 氛围:顶部品牌光晕 + 右下青色一缕(说话人色) */
.hero::before {
  content: ""; position: absolute; inset: -120px -40vw 0;
  pointer-events: none; z-index: -1;
  background:
    radial-gradient(52% 44% at 62% 8%, var(--blue-faint) 0%, transparent 62%),
    radial-gradient(38% 30% at 88% 92%, var(--teal-faint) 0%, transparent 65%);
}

.kicker {
  font-family: var(--mono);
  font-size: 11.5px; letter-spacing: 0.22em;
  color: var(--blue);
  margin-bottom: 22px;
}
.hero h1 {
  font-family: var(--serif);
  font-weight: 900;
  font-size: clamp(38px, 5.4vw, 58px);
  line-height: 1.18;
  letter-spacing: 0.01em;
  color: var(--ink-strong);
}
.hero h1 em {
  font-style: normal;
  color: var(--blue);
  position: relative;
}
/* 手写感下划线 */
.hero h1 em::after {
  content: ""; position: absolute; left: 2%; right: 2%; bottom: 6%;
  height: 0.14em;
  background: var(--blue-line);
  border-radius: 99px;
  z-index: -1;
}
.lede {
  margin-top: 24px;
  max-width: 30em;
  font-size: 16.5px;
  color: var(--ink-muted);
  line-height: 1.85;
}
.hero-cta { display: flex; align-items: center; gap: 18px; margin-top: 34px; flex-wrap: wrap; }
.cta-note { font-size: 12px; color: var(--ink-faint); line-height: 1.6; max-width: 18em; }

.hero-langs { display: flex; align-items: center; gap: 7px; flex-wrap: wrap; margin-top: 36px; }
.lang-pill {
  height: 26px; display: inline-flex; align-items: center; padding: 0 11px;
  font-size: 12px; color: var(--ink-muted);
  background: var(--paper-deep);
  border: 1px solid var(--line);
  border-radius: 99px;
}
.lang-pill.hub {
  color: var(--blue-deep);
  background: var(--blue-faint);
  border-color: var(--blue-line);
  font-weight: 600;
}
.lang-more { font-size: 12px; color: var(--ink-faint); margin-left: 4px; }

/* ── Hero 应用重绘 ── */
.hero-app { position: relative; justify-self: end; width: min(380px, 100%); }
.app-window {
  background: #fff;
  border: 1px solid var(--line-subtle);
  border-radius: 18px;
  box-shadow:
    0 1px 2px rgba(28,25,23,0.04),
    0 24px 64px -24px rgba(28,25,23,0.18),
    0 48px 120px -48px rgba(30,64,175,0.18);
  overflow: hidden;
  transform: rotate(0.8deg);
}
.app-titlebar {
  display: flex; align-items: center; gap: 8px;
  padding: 12px 14px;
  border-bottom: 1px solid var(--line-subtle);
}
.app-logo {
  width: 20px; height: 20px; border-radius: 6px;
  background: linear-gradient(150deg, #4C8DF7, #1E40AF);
  display: inline-flex; align-items: center; justify-content: center; gap: 1.5px;
}
.app-logo i { width: 2px; height: 8px; background: #fff; border-radius: 99px; }
.app-logo i:nth-child(2) { height: 11px; }
.app-title { font-size: 12px; font-weight: 700; color: var(--ink-strong); }
.app-dots { margin-left: auto; display: inline-flex; gap: 6px; }
.app-dots b { width: 8px; height: 8px; border-radius: 99px; background: var(--line); }

.app-sessionbar {
  display: flex; align-items: center; gap: 8px;
  margin: 10px; padding: 9px 12px;
  background: rgba(255,255,255,0.8);
  border: 1px solid var(--line-subtle);
  border-radius: 12px;
  box-shadow: 0 1px 2px rgba(28,25,23,0.04);
  font-size: 11.5px;
}
.dot-live {
  width: 7px; height: 7px; border-radius: 99px; background: #16A34A;
  box-shadow: 0 0 0 3px rgba(22,163,74,0.16);
  animation: pulse 1.8s var(--ease) infinite;
}
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: 0.45; } }
.sb-langs { font-weight: 700; color: var(--ink-strong); }
.sb-timer { font-family: var(--mono); color: var(--ink-faint); font-size: 10.5px; }
.sb-stop {
  margin-left: auto;
  font-size: 10.5px; font-weight: 700; color: #fff;
  background: linear-gradient(180deg, #E03131, #C92A2A);
  padding: 4px 10px; border-radius: 7px;
}

.app-chat { padding: 6px 12px 10px; background: linear-gradient(180deg, rgba(59,130,246,0.04), transparent 40%), var(--paper-deep); display: flex; flex-direction: column; gap: 8px; min-height: 270px; }
.msg {
  max-width: 86%;
  padding: 8px 11px 7px;
  border-radius: 13px;
  font-size: 11px;
  line-height: 1.5;
  opacity: 0;
  animation: bubble .5s var(--ease) forwards;
}
.msg .src { color: var(--ink-strong); font-weight: 500; }
.msg .dst { color: var(--ink-muted); margin-top: 4px; padding-top: 4px; border-top: 1px solid rgba(28,25,23,0.07); font-size: 10.5px; }
.msg.me {
  align-self: flex-end;
  background: linear-gradient(180deg, #E3EDFC, #D7E5FA);
  border-bottom-right-radius: 5px;
}
.msg.me .dst { border-top-color: rgba(30,64,175,0.12); }
.msg.them {
  align-self: flex-start;
  background: #fff;
  border-bottom-left-radius: 5px;
  box-shadow: 0 1px 2px rgba(28,25,23,0.05);
}
.b1 { animation-delay: .5s; } .b2 { animation-delay: 1.1s; }
.b3 { animation-delay: 1.7s; } .b4 { animation-delay: 2.3s; }
@keyframes bubble { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }

.caret {
  display: inline-block; width: 2px; height: 1em; margin-left: 2px;
  background: var(--teal); vertical-align: text-bottom;
  animation: pulse 1s var(--ease) infinite;
}
.dots { display: inline-flex; gap: 3px; align-items: center; height: 12px; }
.dots i {
  width: 4px; height: 4px; border-radius: 99px; background: var(--ink-faint);
  animation: typing 1.2s var(--ease) infinite;
}
.dots i:nth-child(2) { animation-delay: .15s; }
.dots i:nth-child(3) { animation-delay: .3s; }
@keyframes typing { 0%,60%,100% { opacity: .25; transform: translateY(0); } 30% { opacity: 1; transform: translateY(-2px); } }

.app-footer {
  display: flex; align-items: center; justify-content: space-between;
  padding: 9px 14px;
  border-top: 1px solid var(--line-subtle);
  font-family: var(--mono); font-size: 9.5px; color: var(--ink-faint);
}
.af-mic { display: inline-flex; align-items: center; gap: 5px; }
.af-usage b { color: var(--blue); }

/* 悬浮字幕条 — 叠在窗口左下,展示第二形态 */
.float-subtitle {
  position: absolute;
  left: -46px; bottom: -30px;
  width: 270px;
  padding: 12px 16px;
  background: rgba(28, 27, 25, 0.94);
  border: 1px solid rgba(255,255,255,0.07);
  border-radius: 13px;
  box-shadow: 0 16px 44px -16px rgba(0,0,0,0.5);
  backdrop-filter: blur(8px);
  transform: rotate(-1.2deg);
  animation: bubble .6s var(--ease) 2.9s backwards;
}
.fs-badge {
  display: inline-flex; align-items: center;
  height: 18px; padding: 0 8px; margin-bottom: 6px;
  font-size: 10px; font-weight: 700;
  color: #5EDAD0; background: rgba(79,209,197,0.14);
  border-radius: 99px;
}
.float-subtitle p { color: #F8F7F4; font-size: 13.5px; font-weight: 600; line-height: 1.5; }

/* ── 区块通用 ── */
section { position: relative; z-index: 2; }
.sec-title {
  font-family: var(--serif);
  font-weight: 700;
  font-size: clamp(26px, 3.4vw, 36px);
  color: var(--ink-strong);
  letter-spacing: 0.01em;
  text-align: center;
}
.sec-sub { text-align: center; color: var(--ink-muted); margin-top: 12px; font-size: 15px; }

/* ── 工作原理 ── */
.how { max-width: var(--maxw); margin: 0 auto; padding: 90px 28px; border-top: 1px solid var(--line-subtle); }
.flow {
  display: flex; flex-direction: column; gap: 12px; align-items: center;
  margin: 40px auto 0; width: fit-content;
  padding: 26px 34px;
  background: #fff;
  border: 1px solid var(--line-subtle);
  border-radius: 18px;
  box-shadow: 0 1px 2px rgba(28,25,23,0.03), 0 18px 48px -22px rgba(28,25,23,0.12);
}
.flow-row { display: flex; align-items: center; gap: 14px; }
.pill {
  display: inline-flex; align-items: center; gap: 7px;
  height: 32px; padding: 0 14px;
  border-radius: 99px; font-size: 13px; font-weight: 600;
}
.pill b { width: 6px; height: 6px; border-radius: 99px; background: currentColor; }
.me-pill   { color: var(--blue-deep); background: var(--blue-faint); }
.them-pill { color: var(--teal); background: var(--teal-faint); }
.out-pill  { color: var(--ink-muted); background: #fff; border: 1px solid var(--line); font-weight: 500; }
.out-pill strong { color: var(--ink-strong); }
.arrow { color: var(--ink-faint); display: inline-flex; }

.how-steps {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px;
  max-width: 920px; margin: 56px auto 0;
}
.step {
  padding: 26px 24px;
  background: #fff;
  border: 1px solid var(--line-subtle);
  border-radius: 16px;
  box-shadow: 0 1px 2px rgba(28,25,23,0.03);
}
.step-num {
  font-family: var(--mono); font-size: 12px; font-weight: 600;
  color: var(--blue); letter-spacing: 0.12em;
}
.step h3 { font-size: 16.5px; margin: 12px 0 8px; color: var(--ink-strong); }
.step p { font-size: 13.5px; color: var(--ink-muted); line-height: 1.75; }

/* ── 功能 ── */
.features { max-width: var(--maxw); margin: 0 auto; padding: 90px 28px; border-top: 1px solid var(--line-subtle); }
.feat-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
  margin-top: 48px;
}
.feat {
  padding: 26px 24px;
  background: #fff;
  border: 1px solid var(--line-subtle);
  border-radius: 16px;
  transition: transform .25s var(--ease), box-shadow .25s var(--ease);
}
.feat:hover {
  transform: translateY(-3px);
  box-shadow: 0 18px 44px -20px rgba(28,25,23,0.16);
}
.feat-icon {
  width: 38px; height: 38px; border-radius: 11px;
  display: grid; place-items: center;
  color: var(--blue);
  background: var(--blue-faint);
  margin-bottom: 16px;
}
.feat h3 { font-size: 16px; color: var(--ink-strong); margin-bottom: 7px; }
.feat p { font-size: 13.5px; color: var(--ink-muted); line-height: 1.75; }

/* ── 价格 ── */
.pricing { max-width: var(--maxw); margin: 0 auto; padding: 90px 28px; border-top: 1px solid var(--line-subtle); }
.plan-grid {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px;
  max-width: 760px; margin: 48px auto 0;
  align-items: stretch;
}
.plan {
  position: relative;
  display: flex; flex-direction: column;
  padding: 36px 32px;
  background: #fff;
  border: 1px solid var(--line-subtle);
  border-radius: 20px;
  box-shadow: 0 1px 2px rgba(28,25,23,0.03), 0 18px 48px -24px rgba(28,25,23,0.12);
}
.plan-featured {
  border-color: var(--blue-line);
  background: linear-gradient(160deg, rgba(59,130,246,0.06), transparent 50%), #fff;
  box-shadow: 0 1px 2px rgba(28,25,23,0.03), 0 28px 72px -30px rgba(30,64,175,0.28);
}
.plan-badge {
  position: absolute; top: -11px; right: 24px;
  display: inline-flex; align-items: center;
  height: 24px; padding: 0 14px;
  font-size: 12px; font-weight: 700; color: #fff;
  background: linear-gradient(180deg, #3B82F6 0%, #2563EB 100%);
  border-radius: 99px;
  box-shadow: 0 6px 16px -6px rgba(37,99,235,0.5), inset 0 1px 0 rgba(255,255,255,0.25);
}
.plan-head { padding-bottom: 22px; margin-bottom: 22px; border-bottom: 1px solid var(--line-subtle); }
.plan-name {
  font-family: var(--serif); font-weight: 700;
  font-size: 20px; color: var(--ink-strong);
}
.plan-price { margin-top: 16px; display: flex; align-items: baseline; gap: 2px; flex-wrap: wrap; }
.plan-cur { font-family: var(--mono); font-size: 24px; font-weight: 600; color: var(--ink-muted); }
.plan-amt { font-family: var(--mono); font-size: 52px; font-weight: 600; color: var(--ink-strong); line-height: 1; letter-spacing: -0.01em; }
.plan-per { font-size: 14px; color: var(--ink-faint); margin-left: 6px; }
.plan-tagline { font-size: 12.5px; color: var(--blue-deep); font-weight: 600; margin-top: 8px; }
.plan-points { list-style: none; display: flex; flex-direction: column; gap: 11px; flex: 1; }
.plan-points li {
  position: relative; padding-left: 24px;
  font-size: 14px; color: var(--ink); line-height: 1.6;
}
.plan-points li::before {
  content: ""; position: absolute; left: 0; top: 6px;
  width: 12px; height: 7px;
  border-left: 2px solid var(--blue); border-bottom: 2px solid var(--blue);
  transform: rotate(-45deg);
}
.plan-points strong { font-family: var(--mono); color: var(--blue-deep); }
.plan-cta { margin-top: 28px; }
.plan-foot {
  max-width: 640px; margin: 28px auto 0;
  text-align: center; font-size: 13px; color: var(--ink-faint); line-height: 1.75;
}
.plan-foot strong { font-family: var(--mono); color: var(--blue-deep); font-weight: 600; }

/* ── FAQ ── */
.faq { max-width: 760px; margin: 0 auto; padding: 90px 28px; border-top: 1px solid var(--line-subtle); }
.faq-list { margin-top: 40px; display: flex; flex-direction: column; gap: 10px; }
details {
  background: #fff;
  border: 1px solid var(--line-subtle);
  border-radius: 13px;
  padding: 0 22px;
  transition: box-shadow .2s var(--ease);
}
details[open] { box-shadow: 0 12px 32px -18px rgba(28,25,23,0.14); }
summary {
  cursor: pointer; list-style: none;
  padding: 17px 0;
  font-size: 15px; font-weight: 600; color: var(--ink-strong);
  display: flex; align-items: center; justify-content: space-between;
}
summary::-webkit-details-marker { display: none; }
summary::after {
  content: "+";
  font-family: var(--mono); font-size: 18px; color: var(--ink-faint);
  transition: transform .2s var(--ease);
}
details[open] summary::after { transform: rotate(45deg); }
details p { padding: 0 0 18px; font-size: 14px; color: var(--ink-muted); line-height: 1.85; }

/* ── 下载 ── */
.download { padding: 100px 28px 110px; border-top: 1px solid var(--line-subtle); }
.dl-card {
  position: relative;
  max-width: 660px; margin: 0 auto;
  text-align: center;
  padding: 64px 40px 56px;
  background:
    radial-gradient(80% 70% at 50% 0%, var(--blue-faint) 0%, transparent 62%),
    #fff;
  border: 1px solid var(--line-subtle);
  border-radius: 24px;
  box-shadow: 0 1px 2px rgba(28,25,23,0.03), 0 32px 80px -36px rgba(30,64,175,0.25);
  overflow: hidden;
}
/* 同心装饰环 */
.dl-card::before, .dl-card::after {
  content: ""; position: absolute; left: 50%; top: 40%;
  transform: translate(-50%, -50%);
  border: 1px solid var(--blue-line);
  border-radius: 50%; opacity: 0.35; pointer-events: none;
}
.dl-card::before { width: 480px; height: 480px; }
.dl-card::after  { width: 330px; height: 330px; opacity: 0.22; }
.dl-mark {
  width: 56px; height: 56px; border-radius: 16px;
  display: inline-flex; align-items: center; justify-content: center; gap: 3px;
  background: linear-gradient(150deg, #4C8DF7 0%, #2563EB 55%, #1E40AF 100%);
  box-shadow: 0 12px 28px -10px rgba(30,64,175,0.55), inset 0 1px 0 rgba(255,255,255,0.28);
  margin-bottom: 24px;
  position: relative; z-index: 1;
}
.dl-mark i { width: 3.5px; border-radius: 99px; background: rgba(255,255,255,0.95); animation: wave 1.3s var(--ease) infinite; }
.dl-mark i:nth-child(1) { height: 11px; }
.dl-mark i:nth-child(2) { height: 18px; animation-delay: .12s; }
.dl-mark i:nth-child(3) { height: 24px; animation-delay: .24s; }
.dl-mark i:nth-child(4) { height: 18px; animation-delay: .36s; }
.dl-mark i:nth-child(5) { height: 11px; animation-delay: .48s; }
.dl-card h2 {
  font-family: var(--serif); font-weight: 700;
  font-size: clamp(24px, 3vw, 32px); color: var(--ink-strong);
  position: relative; z-index: 1;
}
.dl-card > p { color: var(--ink-muted); margin: 12px 0 28px; font-size: 14px; position: relative; z-index: 1; }
.dl-activate {
  position: relative; z-index: 1;
  font-size: 13px !important; color: var(--ink-muted) !important;
  margin: 18px auto 0 !important; max-width: 30em; line-height: 1.7;
}
.dl-note { font-size: 11.5px !important; color: var(--ink-faint) !important; margin-top: 12px !important; }
.dl-note a { color: var(--ink-muted); }

/* ── Footer ── */
.footer {
  display: flex; align-items: center; justify-content: space-between; gap: 20px;
  max-width: var(--maxw); margin: 0 auto;
  padding: 28px; border-top: 1px solid var(--line-subtle);
  font-size: 12.5px; color: var(--ink-faint);
  flex-wrap: wrap;
}
.foot-left { display: inline-flex; align-items: center; gap: 10px; }
.foot-right { display: inline-flex; align-items: center; gap: 22px; flex-wrap: wrap; }
.foot-right a { color: var(--ink-muted); text-decoration: none; }
.foot-right a:hover { color: var(--ink-strong); }
.icp { color: var(--ink-faint); }

/* ── 进场动效 ── */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .8s var(--ease), transform .8s var(--ease);
}
.reveal.in { opacity: 1; transform: none; }
.d1 { transition-delay: .08s; }
.d2 { transition-delay: .16s; }
.d3 { transition-delay: .24s; }
.d4 { transition-delay: .32s; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .reveal { opacity: 1; transform: none; }
}

/* ── 响应式 ── */
@media (max-width: 920px) {
  .hero { grid-template-columns: 1fr; padding-top: 48px; gap: 64px; }
  .hero-app { justify-self: center; }
  .float-subtitle { left: auto; right: -12px; }
  .how-steps, .feat-grid { grid-template-columns: 1fr; max-width: 480px; margin-inline: auto; }
  .feat-grid { margin-top: 40px; }
  .plan-grid { grid-template-columns: 1fr; max-width: 420px; }
  .topnav { display: none; }
  .flow { padding: 20px; }
  .flow-row { flex-wrap: wrap; justify-content: center; }
}