/* ===== 设计令牌 ===== */
:root {
  --clr-primary:    #0A4B3A;
  --clr-primary-lt: #0d5e49;
  --clr-accent:     #FF6B35;
  --clr-accent-lt:  #ff8458;
  --clr-bg:         #F5F7FA;
  --clr-bg-white:   #FFFFFF;
  --clr-text:       #1D2129;
  --clr-text-muted: #6B7280;
  --clr-border:     #E5E7EB;
  --clr-card:       #FFFFFF;

  --radius-sm:  0.5rem;
  --radius-md:  0.875rem;
  --radius-lg:  1.25rem;
  --radius-xl:  1.75rem;

  --shadow-sm: 0 1px 3px rgba(0,0,0,.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,.08);
  --shadow-lg: 0 8px 32px rgba(0,0,0,.10);

  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'PingFang SC', sans-serif;

  --nav-h: 64px;
}

/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font);
  color: var(--clr-text);
  background: var(--clr-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { text-decoration: none; color: inherit; }
img { display: block; max-width: 100%; }

/* ===== 工具类 ===== */
.container {
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 1.25rem;
}
.text-accent { color: var(--clr-accent); }
.hide-sm { display: none; }
@media (min-width: 768px) { .hide-sm { display: initial; } }

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: transform .15s, opacity .15s, background .15s;
  white-space: nowrap;
}
.btn:active { transform: scale(.97); }
.btn--primary {
  background: var(--clr-primary);
  color: #fff;
}
.btn--primary:hover { background: var(--clr-primary-lt); }
.btn--ghost {
  background: transparent;
  color: var(--clr-primary);
}
.btn--ghost:hover { opacity: .7; }
.btn--sm  { padding: .5rem 1.125rem; font-size: .875rem; }
.btn--lg  { padding: .875rem 1.75rem; font-size: 1rem; }

/* ===== 导航栏 ===== */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: var(--nav-h);
  background: rgba(255,255,255,.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--clr-border);
  transition: box-shadow .2s;
}
.navbar.scrolled { box-shadow: var(--shadow-md); }
.navbar__inner {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 2rem;
}
.navbar__logo {
  display: flex;
  align-items: center;
  gap: .625rem;
  font-weight: 700;
  font-size: 1.0625rem;
  color: var(--clr-text);
  flex-shrink: 0;
}
.logo-mark {
  width: 32px; height: 32px;
  background: var(--clr-primary);
  color: #fff;
  border-radius: .5rem;
  display: grid;
  place-items: center;
  font-size: .875rem;
  font-weight: 800;
}
.logo-text { color: var(--clr-text); }
.navbar__links {
  display: none;
  gap: 1.75rem;
  flex: 1;
}
.navbar__links a {
  font-size: .9375rem;
  font-weight: 500;
  color: var(--clr-text-muted);
  transition: color .15s;
}
.navbar__links a:hover { color: var(--clr-primary); }
.navbar__actions {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: .75rem;
}
.menu-toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: .25rem;
}
.menu-toggle span {
  display: block;
  width: 22px; height: 2px;
  background: var(--clr-text);
  border-radius: 2px;
  transition: transform .2s, opacity .2s;
}
@media (min-width: 768px) {
  .navbar__links { display: flex; }
  .menu-toggle { display: none; }
}
/* mobile nav open */
.navbar.nav-open .navbar__links {
  display: flex;
  flex-direction: column;
  position: fixed;
  top: var(--nav-h); left: 0; right: 0;
  background: #fff;
  padding: 1.5rem 1.25rem;
  border-bottom: 1px solid var(--clr-border);
  box-shadow: var(--shadow-md);
  gap: 1rem;
}
.navbar.nav-open .navbar__links a { font-size: 1.0625rem; }

/* ===== 区块标签 + 标题 ===== */
.section-label {
  display: inline-block;
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--clr-accent);
  margin-bottom: .75rem;
}
.section-title {
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-weight: 800;
  color: var(--clr-text);
  line-height: 1.25;
  margin-bottom: .75rem;
}
.section-desc {
  font-size: 1rem;
  color: var(--clr-text-muted);
  max-width: 560px;
  margin-bottom: 3rem;
}

/* ===== Hero ===== */
.hero {
  padding-top: calc(var(--nav-h) + 4rem);
  padding-bottom: 5rem;
  background: var(--clr-bg-white);
  overflow: hidden;
  position: relative;
}
.hero::before {
  content: '';
  position: absolute;
  top: -160px; right: -160px;
  width: 600px; height: 600px;
  background: oklch(95% .04 150);
  border-radius: 50%;
  pointer-events: none;
}
.hero__inner {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2rem;
  position: relative;
}
.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  background: #ecfdf5;
  color: var(--clr-primary);
  font-size: .8125rem;
  font-weight: 600;
  padding: .375rem .875rem;
  border-radius: 999px;
  border: 1px solid #d1fae5;
}
.hero__title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 800;
  line-height: 1.2;
  color: var(--clr-text);
}
.hero__desc {
  font-size: 1.0625rem;
  color: var(--clr-text-muted);
  max-width: 560px;
  line-height: 1.75;
}
.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: .875rem;
}
.hero__platforms {
  display: flex;
  flex-wrap: wrap;
  gap: .625rem;
}
.platform-tag {
  background: var(--clr-bg);
  color: var(--clr-text-muted);
  font-size: .8125rem;
  font-weight: 500;
  padding: .375rem .875rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--clr-border);
}

/* ===== 手机 Mockup ===== */
.hero__mockup {
  display: none;
  position: absolute;
  right: 0; top: 0;
  width: 300px;
  height: 100%;
  align-items: center;
  justify-content: flex-end;
}
@media (min-width: 900px) {
  .hero__inner { flex-direction: row; align-items: center; }
  .hero__mockup { display: flex; position: static; width: auto; flex-shrink: 0; }
  .hero__title { font-size: clamp(2rem, 3.5vw, 3.25rem); }
}
.phone {
  width: 220px;
  background: #1D2129;
  border-radius: 2.5rem;
  padding: .5rem;
  box-shadow: var(--shadow-lg), 0 0 0 1px rgba(255,255,255,.08);
  animation: phone-float 4s ease-in-out infinite;
}
@keyframes phone-float {
  0%,100% { transform: translateY(0); }
  50%      { transform: translateY(-10px); }
}
.phone__screen {
  background: var(--clr-bg);
  border-radius: 2rem;
  overflow: hidden;
  min-height: 380px;
}
.phone__statusbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: .625rem .875rem .375rem;
  font-size: .625rem;
  font-weight: 600;
  color: var(--clr-text);
  background: var(--clr-bg-white);
}
.phone__app { padding: .75rem; display: flex; flex-direction: column; gap: .75rem; }
.app-header { display: flex; align-items: center; gap: .625rem; }
.app-avatar {
  width: 32px; height: 32px;
  background: var(--clr-primary);
  border-radius: 50%;
}
.app-title { font-size: .6875rem; font-weight: 700; color: var(--clr-text); }
.app-subtitle { font-size: .5625rem; color: var(--clr-text-muted); }
.app-stats {
  display: flex;
  background: var(--clr-bg-white);
  border-radius: var(--radius-md);
  padding: .625rem;
  gap: .5rem;
}
.app-stat { flex: 1; text-align: center; }
.app-stat__num { font-size: .9375rem; font-weight: 800; color: var(--clr-text); }
.app-stat__label { font-size: .5rem; color: var(--clr-text-muted); margin-top: .125rem; }
.app-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: .5rem;
}
.app-card {
  border-radius: var(--radius-sm);
  padding: .625rem;
  font-size: .5625rem;
  font-weight: 600;
  display: flex;
  flex-direction: column;
  gap: .25rem;
}
.app-card__icon { font-size: .9375rem; }
.app-card--green  { background: #ecfdf5; color: var(--clr-primary); }
.app-card--orange { background: #fff7ed; color: var(--clr-accent); }
.app-card--purple { background: #f5f3ff; color: #7c3aed; }
.app-card--blue   { background: #eff6ff; color: #2563eb; }

/* ===== 核心功能4格 ===== */
.features-grid {
  padding: 5rem 0;
  background: var(--clr-bg);
}
.grid-4 {
  display: grid;
  gap: 1.25rem;
  grid-template-columns: 1fr;
}
@media (min-width: 600px) { .grid-4 { grid-template-columns: 1fr 1fr; } }
@media (min-width: 960px) { .grid-4 { grid-template-columns: repeat(4, 1fr); } }

.feature-card {
  background: var(--clr-card);
  border-radius: var(--radius-lg);
  padding: 1.75rem 1.5rem;
  border: 1px solid var(--clr-border);
  transition: transform .2s, box-shadow .2s;
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.feature-card__icon {
  font-size: 1.75rem;
  margin-bottom: 1rem;
}
.feature-card h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: .5rem;
}
.feature-card p {
  font-size: .875rem;
  color: var(--clr-text-muted);
  line-height: 1.65;
}
.feature-card--green  { border-top: 3px solid var(--clr-primary); }
.feature-card--orange { border-top: 3px solid var(--clr-accent); }
.feature-card--purple { border-top: 3px solid #7c3aed; }
.feature-card--blue   { border-top: 3px solid #2563eb; }

/* ===== 功能详情列表 ===== */
.features-list {
  padding: 5rem 0;
  background: var(--clr-bg-white);
}
.features-list__grid {
  display: grid;
  gap: 0;
}
.feature-item {
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
  padding: 1.875rem 0;
  border-bottom: 1px solid var(--clr-border);
  transition: background .15s;
}
.feature-item:last-child { border-bottom: none; }
.feature-item:hover { background: var(--clr-bg); margin: 0 -1.25rem; padding-left: 1.25rem; padding-right: 1.25rem; border-radius: var(--radius-md); }
.feature-item__number {
  font-size: .6875rem;
  font-weight: 800;
  color: var(--clr-text-muted);
  letter-spacing: .04em;
  min-width: 2rem;
  padding-top: .25rem;
}
.feature-item__content h3 {
  font-size: 1.0625rem;
  font-weight: 700;
  margin-bottom: .375rem;
}
.feature-item__content p {
  font-size: .9375rem;
  color: var(--clr-text-muted);
  line-height: 1.65;
  margin-bottom: .75rem;
}
.feature-tags { display: flex; flex-wrap: wrap; gap: .5rem; }
.tag {
  font-size: .75rem;
  font-weight: 500;
  color: var(--clr-primary);
  background: #ecfdf5;
  border-radius: 999px;
  padding: .25rem .75rem;
  border: 1px solid #d1fae5;
}

/* ===== 数据统计 ===== */
.stats {
  background: var(--clr-primary);
  padding: 4rem 0;
}
.stats__grid {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  justify-content: center;
  align-items: center;
}
.stat-item {
  display: flex;
  align-items: baseline;
  gap: .125rem;
  flex-direction: row;
  flex-wrap: wrap;
  justify-content: center;
  min-width: 120px;
  text-align: center;
  flex-direction: column;
  align-items: center;
}
.stat-item__num {
  font-size: 2.5rem;
  font-weight: 800;
  color: #fff;
  line-height: 1;
}
.stat-item__suffix {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--clr-accent);
  display: inline;
}
.stat-item__label {
  font-size: .875rem;
  color: rgba(255,255,255,.65);
  margin-top: .375rem;
}
.stat-divider {
  width: 1px;
  height: 3rem;
  background: rgba(255,255,255,.15);
  display: none;
}
@media (min-width: 640px) {
  .stat-divider { display: block; }
  .stats__grid { flex-wrap: nowrap; }
}

/* ===== 用户评价 ===== */
.testimonials {
  padding: 5rem 0;
  background: var(--clr-bg);
}
.testimonials__grid {
  display: grid;
  gap: 1.25rem;
  grid-template-columns: 1fr;
}
@media (min-width: 640px)  { .testimonials__grid { grid-template-columns: 1fr 1fr; } }
@media (min-width: 1024px) { .testimonials__grid { grid-template-columns: repeat(3, 1fr); } }

.testimonial-card {
  background: var(--clr-card);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  border: 1px solid var(--clr-border);
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: transform .2s, box-shadow .2s;
}
.testimonial-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}
.testimonial-card__stars { color: #FBBF24; font-size: 1rem; letter-spacing: .1em; }
.testimonial-card__text {
  font-size: .9375rem;
  color: var(--clr-text);
  line-height: 1.7;
  flex: 1;
}
.testimonial-card__author {
  display: flex;
  align-items: center;
  gap: .75rem;
  padding-top: 1rem;
  border-top: 1px solid var(--clr-border);
}
.testimonial-card__avatar {
  width: 36px; height: 36px;
  border-radius: 50%;
  background: var(--clr-primary);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: .875rem;
  font-weight: 700;
  flex-shrink: 0;
}
.testimonial-card__name {
  font-size: .9375rem;
  font-weight: 700;
  color: var(--clr-text);
}
.testimonial-card__role {
  font-size: .8125rem;
  color: var(--clr-text-muted);
}

/* ===== 下载 CTA ===== */
.download {
  padding: 5rem 0;
  background: var(--clr-bg-white);
  text-align: center;
}
.download__inner { display: flex; flex-direction: column; align-items: center; }
.download__title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 800;
  margin-bottom: .75rem;
}
.download__desc {
  font-size: 1rem;
  color: var(--clr-text-muted);
  margin-bottom: 2rem;
}
.download__btns {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  margin-bottom: 1.25rem;
}
.download-btn {
  display: flex;
  align-items: center;
  gap: .875rem;
  background: var(--clr-text);
  color: #fff;
  border-radius: var(--radius-md);
  padding: .875rem 1.5rem;
  min-width: 180px;
  transition: opacity .15s, transform .15s;
}
.download-btn:hover { opacity: .85; transform: translateY(-2px); }
.download-btn__icon { font-size: 1.5rem; }
.download-btn__sub { font-size: .6875rem; opacity: .75; line-height: 1; }
.download-btn__main { font-size: 1rem; font-weight: 700; line-height: 1.4; }
.download__note {
  font-size: .875rem;
  color: var(--clr-text-muted);
}

/* ===== 页脚 ===== */
.footer {
  background: #111827;
  color: rgba(255,255,255,.8);
}
.footer__inner {
  display: flex;
  flex-wrap: wrap;
  gap: 3rem;
  padding: 3.5rem 1.25rem 2.5rem;
}
.footer__brand {
  flex: 1;
  min-width: 200px;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}
.footer__brand .navbar__logo { color: #fff; }
.footer__brand .logo-mark { background: var(--clr-accent); }
.footer__brand p {
  font-size: .875rem;
  color: rgba(255,255,255,.5);
  max-width: 240px;
  line-height: 1.65;
}
.footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: 2.5rem;
}
.footer__col {
  display: flex;
  flex-direction: column;
  gap: .75rem;
  min-width: 100px;
}
.footer__col h4 {
  font-size: .875rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: .25rem;
}
.footer__col a {
  font-size: .875rem;
  color: rgba(255,255,255,.5);
  transition: color .15s;
}
.footer__col a:hover { color: #fff; }
.footer__bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding: 1.25rem;
  font-size: .8125rem;
  color: rgba(255,255,255,.35);
}

/* ===== 滚入动画 ===== */
.fade-up {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .55s cubic-bezier(.22,1,.36,1), transform .55s cubic-bezier(.22,1,.36,1);
}
.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}
.fade-up:nth-child(2) { transition-delay: .08s; }
.fade-up:nth-child(3) { transition-delay: .16s; }
.fade-up:nth-child(4) { transition-delay: .24s; }