/* ============================================================
   离沐网络工作室 - 备案演示网站
   ============================================================ */

:root {
  --paper: #fbf8f3;
  --paper-2: #f4efe6;
  --ink: #14181f;
  --ink-2: #1c1917;
  --muted: #6b6258;
  --line: #e6ddd0;
  --accent: #c2410c;        /* 焦橙 */
  --accent-soft: #fb923c;
  --teal: #0f766e;          /* 青墨 */
  --gold: #b08d57;
  --radius: 14px;
  --radius-sm: 8px;
  --maxw: 1200px;
  --shadow: 0 10px 40px -12px rgba(20, 24, 31, 0.18);
  --shadow-lg: 0 30px 80px -30px rgba(20, 24, 31, 0.35);
  --font-display: "Noto Serif SC", "Source Han Serif SC", "Songti SC", serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  background: var(--paper);
  color: var(--ink-2);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }

a { color: inherit; text-decoration: none; }

/* ---------- 顶部导航 ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(251, 248, 243, 0.82);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 16px 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 20px;
  letter-spacing: 1px;
  color: var(--ink);
}
.brand-mark {
  width: 38px; height: 38px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--accent), var(--gold));
  display: grid;
  place-items: center;
  color: #fff;
  font-weight: 800;
  font-size: 18px;
  box-shadow: 0 6px 18px -6px rgba(194, 65, 12, 0.6);
  position: relative;
}
.brand-mark::after {
  content: "";
  position: absolute;
  inset: 3px;
  border-radius: 7px;
  border: 1.5px solid rgba(255,255,255,0.55);
}
.brand small {
  display: block;
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 3px;
  color: var(--muted);
  font-family: var(--font-body);
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 6px;
  list-style: none;
}
.nav-links a {
  padding: 8px 16px;
  border-radius: 999px;
  font-size: 14.5px;
  color: var(--ink-2);
  transition: all .2s ease;
  position: relative;
}
.nav-links a:hover { color: var(--accent); background: rgba(194,65,12,0.08); }
.nav-links a.active {
  color: var(--accent);
  background: rgba(194,65,12,0.1);
}
.nav-cta {
  padding: 9px 20px !important;
  background: var(--ink);
  color: #fff !important;
  margin-left: 8px;
  font-weight: 600;
}
.nav-cta:hover { background: var(--accent) !important; }

.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  width: 40px; height: 40px;
  border-radius: 10px;
}
.menu-toggle span {
  display: block;
  width: 22px; height: 2px;
  background: var(--ink);
  margin: 5px auto;
  transition: .3s;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  background: var(--ink);
  color: #f5efe6;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 18% 20%, rgba(194,65,12,0.25), transparent 45%),
    radial-gradient(circle at 82% 70%, rgba(15,118,110,0.22), transparent 50%);
  pointer-events: none;
}
.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.04) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(circle at 50% 40%, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(circle at 50% 40%, #000 30%, transparent 75%);
}
.hero-inner {
  position: relative;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 120px 28px 130px;
  text-align: center;
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 7px 18px;
  border: 1px solid rgba(255,255,255,0.18);
  border-radius: 999px;
  font-size: 13px;
  letter-spacing: 2px;
  color: var(--accent-soft);
  background: rgba(255,255,255,0.04);
  margin-bottom: 30px;
}
.eyebrow .dot {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--accent-soft);
  box-shadow: 0 0 12px var(--accent-soft);
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%,100% { opacity: 1; transform: scale(1); }
  50% { opacity: .5; transform: scale(1.4); }
}
.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(34px, 6vw, 68px);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: 2px;
  margin-bottom: 26px;
}
.hero h1 .grad {
  background: linear-gradient(120deg, var(--accent-soft), #fbbf24 60%, var(--teal));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero p.lead {
  font-size: clamp(15px, 2vw, 19px);
  color: rgba(245,239,230,0.78);
  max-width: 680px;
  margin: 0 auto 40px;
}
.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 14px 30px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all .25s ease;
  font-family: inherit;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), #ea580c);
  color: #fff;
  box-shadow: 0 12px 30px -10px rgba(194,65,12,0.7);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 36px -10px rgba(194,65,12,0.85); }
.btn-ghost {
  background: transparent;
  color: #f5efe6;
  border: 1px solid rgba(255,255,255,0.28);
}
.btn-ghost:hover { background: rgba(255,255,255,0.08); border-color: rgba(255,255,255,0.5); }
.btn-dark {
  background: var(--ink);
  color: #fff;
}
.btn-dark:hover { background: var(--accent); }
.btn-outline {
  background: transparent;
  color: var(--ink);
  border: 1.5px solid var(--ink);
}
.btn-outline:hover { background: var(--ink); color: #fff; }

/* ---------- 数据条 ---------- */
.stats {
  max-width: var(--maxw);
  margin: -60px auto 0;
  padding: 0 28px;
  position: relative;
  z-index: 2;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  background: var(--paper);
}
.stat {
  background: var(--paper);
  padding: 32px 24px;
  text-align: center;
  transition: background .2s;
}
.stat:hover { background: var(--paper-2); }
.stat .num {
  font-family: var(--font-display);
  font-size: 38px;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 8px;
}
.stat .num sup { font-size: 18px; }
.stat .lbl {
  font-size: 13px;
  color: var(--muted);
  letter-spacing: 1px;
}

/* ---------- 通用 section ---------- */
.section {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 100px 28px;
}
.section-head {
  text-align: center;
  margin-bottom: 64px;
}
.section-tag {
  display: inline-block;
  font-size: 13px;
  letter-spacing: 4px;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 16px;
}
.section-head h2 {
  font-family: var(--font-display);
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 800;
  color: var(--ink);
  letter-spacing: 1px;
  line-height: 1.3;
  margin-bottom: 16px;
}
.section-head p {
  color: var(--muted);
  font-size: 16px;
  max-width: 620px;
  margin: 0 auto;
}

/* ---------- 服务卡片 ---------- */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}
.service-card {
  position: relative;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 40px 32px 36px;
  transition: all .3s ease;
  overflow: hidden;
}
.service-card::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--gold));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .35s ease;
}
.service-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}
.service-card:hover::before { transform: scaleX(1); }
.service-icon {
  width: 62px; height: 62px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  margin-bottom: 24px;
  background: linear-gradient(135deg, rgba(194,65,12,0.12), rgba(176,141,87,0.12));
  color: var(--accent);
}
.service-card h3 {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--ink);
}
.service-card p {
  color: var(--muted);
  font-size: 14.5px;
  margin-bottom: 22px;
}
.service-feats {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.service-feats li {
  font-size: 13.5px;
  color: var(--ink-2);
  display: flex;
  align-items: center;
  gap: 10px;
}
.service-feats li::before {
  content: "";
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--teal);
  flex-shrink: 0;
}
.service-more {
  margin-top: 26px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--accent);
  font-size: 14px;
  font-weight: 600;
  transition: gap .2s;
}
.service-more:hover { gap: 12px; }

/* ---------- 关于介绍（双色块） ---------- */
.about-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
}
.about-visual {
  position: relative;
  border-radius: 20px;
  overflow: hidden;
  aspect-ratio: 4/5;
  background: linear-gradient(150deg, var(--ink), #1f2937);
  box-shadow: var(--shadow-lg);
}
.about-visual .orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(60px);
  opacity: 0.6;
}
.about-visual .orb.a { width: 280px; height: 280px; background: var(--accent); top: -60px; left: -60px; }
.about-visual .orb.b { width: 240px; height: 240px; background: var(--teal); bottom: -40px; right: -40px; }
.about-visual .panel {
  position: absolute;
  left: 32px; right: 32px; bottom: 32px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.15);
  backdrop-filter: blur(10px);
  border-radius: 16px;
  padding: 24px;
  color: #fff;
}
.about-visual .panel h4 {
  font-family: var(--font-display);
  font-size: 20px;
  margin-bottom: 8px;
}
.about-visual .panel p { font-size: 13px; opacity: 0.8; }
.about-text h2 {
  font-family: var(--font-display);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  color: var(--ink);
  margin-bottom: 22px;
  line-height: 1.3;
}
.about-text > p {
  color: var(--ink-2);
  font-size: 15.5px;
  margin-bottom: 18px;
}
.about-text .accent-p {
  color: var(--accent);
  font-weight: 600;
}
.about-points {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  margin-top: 30px;
}
.about-point {
  padding: 20px;
  background: var(--paper-2);
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
}
.about-point h5 {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--ink);
}
.about-point p { font-size: 13px; color: var(--muted); }

/* ---------- 流程 ---------- */
.process {
  background: var(--ink);
  color: #f5efe6;
  border-radius: 24px;
  padding: 70px 50px;
  margin: 0 28px;
  position: relative;
  overflow: hidden;
}
.process::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 90% 10%, rgba(194,65,12,0.18), transparent 40%),
    radial-gradient(circle at 10% 90%, rgba(15,118,110,0.18), transparent 40%);
}
.process-inner { position: relative; max-width: var(--maxw); margin: 0 auto; }
.process-head { text-align: center; margin-bottom: 56px; }
.process-head .section-tag { color: var(--accent-soft); }
.process-head h2 {
  font-family: var(--font-display);
  font-size: clamp(26px, 3.5vw, 38px);
  color: #fff;
  margin-bottom: 14px;
}
.process-head p { color: rgba(245,239,230,0.7); }
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  position: relative;
}
.step {
  position: relative;
  padding: 32px 24px;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius);
  transition: all .3s;
}
.step:hover {
  background: rgba(255,255,255,0.09);
  border-color: rgba(194,65,12,0.5);
  transform: translateY(-4px);
}
.step-num {
  font-family: var(--font-display);
  font-size: 42px;
  font-weight: 800;
  color: var(--accent-soft);
  line-height: 1;
  margin-bottom: 16px;
}
.step h4 { font-size: 17px; margin-bottom: 10px; color: #fff; }
.step p { font-size: 13.5px; color: rgba(245,239,230,0.68); line-height: 1.7; }

/* ---------- 联系 / CTA ---------- */
.cta-band {
  background: linear-gradient(135deg, var(--accent), #ea580c);
  color: #fff;
  border-radius: 24px;
  padding: 60px 50px;
  margin: 0 28px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.cta-band::before {
  content: "";
  position: absolute;
  top: -40px; right: -40px;
  width: 200px; height: 200px;
  border-radius: 50%;
  background: rgba(255,255,255,0.12);
}
.cta-band::after {
  content: "";
  position: absolute;
  bottom: -60px; left: -60px;
  width: 260px; height: 260px;
  border-radius: 50%;
  background: rgba(255,255,255,0.08);
}
.cta-band > * { position: relative; }
.cta-band h2 {
  font-family: var(--font-display);
  font-size: clamp(26px, 3.5vw, 38px);
  margin-bottom: 14px;
}
.cta-band p { opacity: 0.92; margin-bottom: 28px; }
.cta-band .btn { background: #fff; color: var(--accent); }
.cta-band .btn:hover { background: var(--ink); color: #fff; }

/* ---------- 页脚（备案号） ---------- */
.footer {
  background: var(--ink);
  color: rgba(245,239,230,0.7);
  padding: 60px 28px 30px;
  margin-top: 100px;
}
.footer-inner {
  max-width: var(--maxw);
  margin: 0 auto;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}
.footer-brand .brand { color: #fff; margin-bottom: 16px; }
.footer-brand p { font-size: 13.5px; line-height: 1.8; opacity: 0.7; }
.footer-col h5 {
  color: #fff;
  font-size: 14px;
  margin-bottom: 18px;
  font-weight: 600;
  letter-spacing: 1px;
}
.footer-col ul { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.footer-col a { font-size: 13.5px; opacity: 0.65; transition: .2s; }
.footer-col a:hover { opacity: 1; color: var(--accent-soft); }
.footer-bottom {
  text-align: center;
  padding-top: 30px;
}
.footer-bottom .copyright {
  font-size: 13px;
  opacity: 0.55;
  margin-bottom: 12px;
}
/* 备案号 - 底部中央 */
.beian {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  font-size: 13px;
}
.beian a {
  color: rgba(245,239,230,0.75);
  transition: color .2s;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.beian a:hover { color: var(--accent-soft); }
.beian .sep { opacity: 0.3; }
.beian .badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border: 1px solid rgba(255,255,255,0.18);
  border-radius: 6px;
  font-size: 12px;
}

/* ---------- 内页头部 ---------- */
.page-head {
  background: var(--ink);
  color: #fff;
  padding: 90px 28px 80px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.page-head::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 50% 0%, rgba(194,65,12,0.2), transparent 60%);
}
.page-head-inner { position: relative; max-width: 800px; margin: 0 auto; }
.page-head .eyebrow { margin-bottom: 20px; }
.page-head h1 {
  font-family: var(--font-display);
  font-size: clamp(30px, 5vw, 50px);
  font-weight: 800;
  margin-bottom: 18px;
  letter-spacing: 2px;
}
.page-head p { color: rgba(255,255,255,0.7); font-size: 16px; }
.breadcrumb {
  margin-top: 22px;
  font-size: 13px;
  opacity: 0.6;
}
.breadcrumb a:hover { opacity: 1; color: var(--accent-soft); }

/* ---------- 服务详情页 ---------- */
.svc-detail {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 50px;
  align-items: center;
  margin-bottom: 80px;
}
.svc-detail.reverse { direction: rtl; }
.svc-detail.reverse > * { direction: ltr; }
.svc-detail-text .num {
  font-family: var(--font-display);
  font-size: 60px;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 12px;
  opacity: 0.4;
}
.svc-detail-text h2 {
  font-family: var(--font-display);
  font-size: 32px;
  font-weight: 800;
  margin-bottom: 18px;
  color: var(--ink);
}
.svc-detail-text p { color: var(--ink-2); margin-bottom: 20px; }
.svc-detail-text ul { list-style: none; margin-bottom: 26px; }
.svc-detail-text ul li {
  padding: 10px 0;
  border-bottom: 1px dashed var(--line);
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 14.5px;
}
.svc-detail-text ul li svg { color: var(--teal); flex-shrink: 0; }
.svc-detail-visual {
  border-radius: 20px;
  aspect-ratio: 1;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}
.svc-detail-visual.v1 { background: linear-gradient(135deg, #1e293b, #c2410c); }
.svc-detail-visual.v2 { background: linear-gradient(135deg, #0f766e, #1e293b); }
.svc-detail-visual.v3 { background: linear-gradient(135deg, #7c3aed, #c2410c); }
.svc-detail-visual .deco {
  position: absolute;
  border-radius: 50%;
  filter: blur(50px);
  opacity: 0.5;
}
.svc-detail-visual .d1 { width: 200px; height: 200px; background: #fbbf24; top: 20%; left: 15%; }
.svc-detail-visual .d2 { width: 180px; height: 180px; background: #06b6d4; bottom: 15%; right: 10%; }
.svc-detail-visual .content {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: #fff;
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 700;
  text-align: center;
  padding: 30px;
}

/* ---------- 联系页 ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 50px;
}
.contact-info h2 {
  font-family: var(--font-display);
  font-size: 32px;
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--ink);
}
.contact-info > p { color: var(--muted); margin-bottom: 32px; }
.contact-list { display: flex; flex-direction: column; gap: 22px; }
.contact-item {
  display: flex;
  gap: 18px;
  padding: 22px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: .2s;
}
.contact-item:hover { border-color: var(--accent); box-shadow: var(--shadow); }
.contact-item .ico {
  width: 48px; height: 48px;
  border-radius: 12px;
  background: rgba(194,65,12,0.1);
  color: var(--accent);
  display: grid;
  place-items: center;
  flex-shrink: 0;
}
.contact-item h5 { font-size: 14px; color: var(--muted); font-weight: 500; margin-bottom: 4px; }
.contact-item p { font-size: 15px; color: var(--ink); font-weight: 600; }
.contact-form {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 36px;
  box-shadow: var(--shadow);
}
.contact-form h3 {
  font-family: var(--font-display);
  font-size: 22px;
  margin-bottom: 24px;
  color: var(--ink);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.form-group { margin-bottom: 20px; }
.form-group label {
  display: block;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 8px;
}
.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 12px 16px;
  border: 1.5px solid var(--line);
  border-radius: 10px;
  font-size: 14.5px;
  font-family: inherit;
  background: var(--paper);
  transition: .2s;
  color: var(--ink);
}
.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--accent);
  background: #fff;
}
.form-group textarea { resize: vertical; min-height: 110px; }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .services-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .about-wrap { grid-template-columns: 1fr; }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .svc-detail { grid-template-columns: 1fr; }
  .svc-detail.reverse { direction: ltr; }
  .contact-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
}
@media (max-width: 640px) {
  .nav-links { display: none; }
  .menu-toggle { display: block; }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%; left: 0; right: 0;
    background: var(--paper);
    padding: 16px;
    border-bottom: 1px solid var(--line);
  }
  .nav-links.open a { width: 100%; text-align: center; }
  .hero-inner { padding: 80px 20px 100px; }
  .section { padding: 70px 20px; }
  .process, .cta-band { margin: 0 16px; padding: 44px 24px; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .about-points { grid-template-columns: 1fr; }
}

/* 入场动画 */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity .7s ease, transform .7s ease;
}
.reveal.in { opacity: 1; transform: none; }