/* ===== 基础 ===== */
:root {
  --ink: #3b2f2a;
  --ink-soft: #6b5b52;
  --paper: #f6f1e8;
  --paper-deep: #ede4d3;
  --accent: #c74b2b;      /* 红笔 */
  --accent-blue: #2b6cb0; /* 蓝笔 */
  --line: rgba(59, 47, 42, 0.12);
  --white: #fffdf9;
  --shadow-sm: 0 6px 20px rgba(59, 47, 42, 0.08);
  --shadow-lg: 0 24px 60px rgba(59, 47, 42, 0.16);
  --radius: 20px;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
/* 纸感噪点背景 */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.5;
  z-index: 0;
  background-image:
    radial-gradient(rgba(59,47,42,0.05) 1px, transparent 1px);
  background-size: 22px 22px;
}
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  background: rgba(59,47,42,0.08);
  padding: 1px 6px;
  border-radius: 6px;
  font-size: 0.85em;
}

.container { max-width: 1160px; margin: 0 auto; padding: 0 24px; position: relative; z-index: 1; }
.hl {
  color: var(--accent);
  font-family: "Kalam", "Noto Sans SC", cursive;
  font-weight: 700;
}

/* ===== 导航 ===== */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(246, 241, 232, 0.82);
  backdrop-filter: saturate(1.4) blur(14px);
  -webkit-backdrop-filter: saturate(1.4) blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: flex; align-items: center; gap: 11px; }
.brand-logo { width: 38px; height: 38px; border-radius: 10px; box-shadow: var(--shadow-sm); }
.brand-name { font-size: 20px; font-weight: 900; letter-spacing: 1px; }
.brand-name em { font-style: normal; font-size: 12px; color: var(--ink-soft); font-weight: 500; margin-left: 6px; }
.nav-links { display: flex; align-items: center; gap: 30px; }
.nav-links a:not(.nav-cta) { font-size: 15px; color: var(--ink-soft); transition: color .2s; }
.nav-links a:not(.nav-cta):hover { color: var(--ink); }
.nav-cta {
  background: var(--ink);
  color: var(--white) !important;
  padding: 9px 20px;
  border-radius: 999px;
  font-size: 14px !important;
  transition: transform .2s, box-shadow .2s;
}
.nav-cta:hover { transform: translateY(-2px); box-shadow: var(--shadow-sm); }
.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; }
.nav-toggle span { width: 22px; height: 2px; background: var(--ink); border-radius: 2px; transition: .3s; }

/* ===== Hero ===== */
.hero { padding: 84px 0 40px; position: relative; }
.hero-grid { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 48px; align-items: center; }
.hero-eyebrow {
  display: inline-block;
  font-size: 13px;
  letter-spacing: 2px;
  color: var(--accent-blue);
  background: rgba(43,108,176,0.1);
  padding: 6px 14px;
  border-radius: 999px;
  margin-bottom: 22px;
  font-weight: 500;
}
.hero h1 { font-size: clamp(40px, 6vw, 64px); line-height: 1.12; font-weight: 900; letter-spacing: 1px; }
.hero h1 .hl { display: inline-block; transform: rotate(-2deg); }
.hero-sub { margin-top: 24px; font-size: 18px; color: var(--ink-soft); max-width: 520px; }
.hero-sub span { color: var(--ink); font-weight: 700; }
.hero-actions { margin-top: 32px; display: flex; gap: 14px; flex-wrap: wrap; align-items: center; }
.btn {
  display: inline-flex; align-items: center; gap: 9px;
  padding: 14px 26px; border-radius: 999px;
  font-size: 16px; font-weight: 600; cursor: pointer;
  transition: transform .2s, box-shadow .2s, background .2s;
  border: 0;
}
.btn:hover { transform: translateY(-3px); }
.btn-primary { background: var(--accent); color: #fff; box-shadow: 0 10px 26px rgba(199,75,43,0.34); }
.btn-primary:hover { box-shadow: 0 16px 34px rgba(199,75,43,0.4); }
.btn-ghost { background: transparent; color: var(--ink); box-shadow: inset 0 0 0 1.6px var(--line); }
.btn-ghost:hover { box-shadow: inset 0 0 0 1.6px var(--ink); }
.btn-dark { background: var(--ink); color: var(--white); }
.btn-dark:hover { box-shadow: var(--shadow-lg); }
.btn-apple { width: 18px; height: 22px; filter: brightness(0) invert(1); }
.hero-meta { margin-top: 28px; display: flex; gap: 22px; flex-wrap: wrap; list-style: none; }
.hero-meta li { font-size: 13px; color: var(--ink-soft); display: flex; align-items: center; gap: 7px; }
.hero-meta li::before { content: "✓"; color: var(--accent-blue); font-weight: 700; }

.hero { position: relative; overflow: hidden; padding: 140px 0 120px; text-align: left; }

/* 全背景轮播（仅移动端显示，PC 隐藏） */
.hero-bg { display: none; position: absolute; inset: 0; z-index: 0; background: var(--paper-soft); }
.hero-bg .bg-slide {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  opacity: 0;
  transition: opacity 1.1s ease;
}
.hero-bg .bg-slide.active { opacity: 1; }
.hero-scrim {
  position: absolute;
  inset: 0;
  z-index: 1;
  background: linear-gradient(
    90deg,
    rgba(31, 23, 19, 0.82),
    rgba(31, 23, 19, 0.45) 55%,
    rgba(31, 23, 19, 0.18)
  );
}
.hero-bg-dots {
  position: absolute;
  bottom: 28px;
  left: 0;
  right: 0;
  z-index: 2;
  display: flex;
  justify-content: center;
  gap: 10px;
}
.hero-bg-dots i {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: rgba(255, 253, 249, 0.5);
  cursor: pointer;
  transition: background .3s, transform .3s;
}
.hero-bg-dots i.on { background: var(--white); transform: scale(1.3); }

.hero-grid { position: relative; z-index: 3; }
.hero-copy { color: var(--ink); }

/* PC 右侧轮播卡片 */
.hero-art { position: relative; }
.hero-card {
  position: relative;
  border-radius: 24px;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  transform: rotate(1.5deg);
  background: var(--white);
  border: 1px solid var(--line);
  aspect-ratio: 4 / 5;
}
.hero-card .slide {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  opacity: 0;
  transition: opacity .8s ease;
}
.hero-card .slide.active { opacity: 1; }
.hero-dots {
  position: absolute;
  bottom: 14px;
  left: 0;
  right: 0;
  z-index: 2;
  display: flex;
  justify-content: center;
  gap: 8px;
}
.hero-dots i {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: rgba(255, 253, 249, 0.6);
  cursor: pointer;
  transition: background .3s, transform .3s;
  border: 1px solid rgba(59, 47, 42, 0.15);
}
.hero-dots i.on { background: var(--white); transform: scale(1.25); }

/* ===== Quote ===== */
.quote { padding: 70px 0; text-align: center; position: relative; }
.quote::before { content: ""; position: absolute; left: 50%; top: 0; width: 1px; height: 100%; background: linear-gradient(var(--line), transparent); }
.quote-text { font-size: clamp(20px, 3vw, 28px); font-weight: 500; font-family: "Kalam", "Noto Sans SC", cursive; }
.quote-note { margin-top: 14px; color: var(--ink-soft); font-size: 14px; }

/* ===== Section head & features ===== */
.features { padding: 70px 0; }
.section-head { text-align: center; max-width: 640px; margin: 0 auto 50px; }
.kicker {
  font-size: 12px; letter-spacing: 3px; text-transform: uppercase; color: var(--accent-blue);
  font-weight: 700; opacity: .8;
}
.section-head h2 { font-size: clamp(28px, 4vw, 40px); font-weight: 900; margin: 10px 0 14px; line-height: 1.25; }
.section-head p { color: var(--ink-soft); }
.section-head .hl { font-family: "Kalam", "Noto Sans SC", cursive; }

.feature-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.feat {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 22px;
  transition: transform .25s, box-shadow .25s;
}
.feat:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.feat-icon {
  width: 52px; height: 52px; border-radius: 14px;
  display: grid; place-items: center;
  font-size: 24px;
  background: linear-gradient(135deg, var(--paper), var(--paper-deep));
  border: 1px solid var(--line);
  margin-bottom: 16px;
}
.feat h3 { font-size: 17px; font-weight: 700; margin-bottom: 10px; }
.feat p { font-size: 14px; color: var(--ink-soft); }

/* ===== Gallery ===== */
.gallery { padding: 70px 0; }
.gallery-scroll {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 260px;
  gap: 22px;
  overflow-x: auto;
  padding: 8px 4px 22px;
  scroll-snap-type: x mandatory;
  scrollbar-width: thin;
  scrollbar-color: var(--line) transparent;
}
.gallery-scroll::-webkit-scrollbar { height: 8px; }
.gallery-scroll::-webkit-scrollbar-thumb { background: var(--line); border-radius: 8px; }
.gitem {
  scroll-snap-align: center;
  border-radius: 16px;
  overflow: hidden;
  background: var(--white);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
  transition: transform .25s;
}
.gitem:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.gitem img { width: 100%; height: auto; display: block; }
.gitem figcaption {
  padding: 11px 14px;
  font-size: 13px;
  color: var(--ink-soft);
  font-family: "Kalam", "Noto Sans SC", cursive;
}
.gallery-hint {
  text-align: center;
  color: var(--ink-soft);
  font-size: 13px;
  display: flex; gap: 10px; align-items: center; justify-content: center; margin-top: 4px;
}
.gallery-hint .dot { width: 5px; height: 5px; border-radius: 50%; background: var(--ink-soft); opacity: .5; }

/* ===== How ===== */
.how { padding: 70px 0; }
.how-inner { max-width: 900px; }
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin-top: 10px; }
.step {
  display: flex; flex-direction: column; align-items: flex-start;
  background: rgba(255, 253, 249, 0.7);
  border: 1px dashed var(--line);
  border-radius: var(--radius);
  padding: 28px;
}
.step-num {
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--ink); color: var(--white);
  display: grid; place-items: center;
  font-weight: 900; font-size: 18px;
  margin-bottom: 18px;
  font-family: "Kalam", cursive;
}
.step h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.step p { color: var(--ink-soft); font-size: 14px; }

/* ===== Download ===== */
.download { padding: 40px 0 80px; }
.download-card {
  background: linear-gradient(135deg, var(--ink), #54423a);
  color: var(--white);
  border-radius: 30px;
  text-align: center;
  padding: 64px 28px 54px;
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}
.download-card::before {
  content: "";
  position: absolute; inset: 0;
  opacity: .5;
  background-image: radial-gradient(rgba(255,255,255,0.09) 1px, transparent 1px);
  background-size: 20px 20px;
}
.download-icon { width: 84px; height: 84px; border-radius: 20px; margin: 0 auto 18px; box-shadow: 0 12px 30px rgba(0,0,0,0.3); }
.download-icon img { width: 100%; border-radius: 20px; }
.download-card h2 { font-size: clamp(26px, 4vw, 36px); font-weight: 900; margin-bottom: 12px; position: relative; }
.download-card p { color: rgba(255,255,255,0.8); position: relative; }
.download-card .btn { margin-top: 26px; position: relative; }
.download-sub { margin-top: 16px !important; font-size: 13px; color: rgba(255,255,255,0.55); }

/* ===== Footer ===== */
.footer { border-top: 1px solid var(--line); padding: 40px 0; }
.footer-inner { display: flex; flex-direction: column; align-items: center; gap: 8px; text-align: center; }
.footer-brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 17px; }
.footer-brand img { width: 26px; height: 26px; border-radius: 6px; }
.footer-note { color: var(--ink-soft); font-size: 14px; }
.footer-copy { color: rgba(107,91,82,0.7); font-size: 12px; }

/* ===== 响应式 ===== */
@media (max-width: 980px) {
  .hero { min-height: 100vh; display: flex; align-items: center; }
  .hero-bg { display: block; }
  .hero-art { display: none; }
  .hero-copy { color: var(--white); }
  .hero-eyebrow { color: #fff; background: rgba(255,255,255,0.16); }
  .hero h1 { color: var(--white); }
  .hero h1 .hl { color: #ffd9c4; }
  .hero-sub { color: rgba(255,253,249,0.88); }
  .hero-sub span { color: #fff; }
  .hero .btn-ghost { color: #fff; box-shadow: inset 0 0 0 1.6px rgba(255,255,255,0.6); }
  .hero .btn-ghost:hover { box-shadow: inset 0 0 0 1.6px var(--white); }
  .hero-meta li { color: rgba(255,253,249,0.9); }
  .hero-meta li::before { color: #ffd9c4; }
  .hero-grid { grid-template-columns: 1fr; gap: 60px; text-align: center; }
  .hero-copy .hero-eyebrow, .hero-actions, .hero-meta { justify-content: center; margin-left: auto; margin-right: auto; }
  .hero-sub { margin-left: auto; margin-right: auto; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 720px) {
  .nav-links {
    position: fixed; top: 0; right: 0; height: 100vh; width: min(280px, 78vw);
    background: var(--paper); flex-direction: column; align-items: flex-start;
    justify-content: center; gap: 26px; padding: 40px;
    box-shadow: -20px 0 60px rgba(59,47,42,0.18);
    transform: translateX(100%); transition: transform .3s;
    border-left: 1px solid var(--line);
  }
  .nav-links.open { transform: translateX(0); }
  .nav-toggle { display: flex; z-index: 60; }
  .feature-grid { grid-template-columns: 1fr; }
  .steps { grid-template-columns: 1fr; }
  .hero { padding-top: 48px; }
}
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
}