/* =========================================================
   YBFC-Studio 官网 · 苹果风样式
   ========================================================= */

:root {
  --bg: #ffffff;
  --bg-alt: #f5f5f7;
  --ink: #1d1d1f;
  --ink-soft: #6e6e73;
  --line: #d2d2d7;
  --blue: #0071e3;
  --blue-hover: #0077ed;
  --radius: 18px;
  --maxw: 980px;
  --nav-h: 48px;
  --ease: cubic-bezier(0.28, 0.11, 0.32, 1);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display",
    "SF Pro Text", "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

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

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 22px; }

/* ---------- 导航 ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-h);
  background: rgba(255, 255, 255, 0.72);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}
.nav-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  height: 100%;
  padding: 0 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  display: flex;
  align-items: center;
}
.nav-logo-img { height: 24px; width: auto; display: block; }
.nav-right { display: flex; align-items: center; gap: 14px; }
.lang-switch {
  font-size: 12px;
  font-weight: 600;
  padding: 5px 12px;
  border-radius: 980px;
  border: 1px solid var(--line);
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  transition: background 0.25s, border-color 0.25s;
}
.lang-switch:hover { background: var(--bg-alt); }
.nav-links { display: flex; gap: 30px; }
.nav-links a {
  font-size: 13px;
  color: var(--ink);
  opacity: 0.85;
  transition: opacity 0.25s;
}
.nav-links a:hover { opacity: 1; }
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
}
.nav-toggle span {
  width: 20px;
  height: 1.5px;
  background: var(--ink);
  transition: transform 0.3s, opacity 0.3s;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block;
  font-size: 15px;
  padding: 10px 20px;
  border-radius: 980px;
  transition: background 0.25s, transform 0.15s, opacity 0.25s;
}
.btn:active { transform: scale(0.97); }
.btn-primary { background: var(--blue); color: #fff; }
.btn-primary:hover { background: var(--blue-hover); }
.btn-ghost { color: var(--blue); }
.btn-ghost:hover { text-decoration: underline; }
.btn-lg { font-size: 17px; padding: 14px 30px; }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: calc(100vh - var(--nav-h));
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 80px 22px;
  overflow: hidden;
}
.hero-content { position: relative; z-index: 2; }
.hero-eyebrow {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 3px;
  color: var(--blue);
  margin-bottom: 14px;
}
.hero-title {
  font-size: clamp(40px, 8vw, 80px);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.05;
  background: linear-gradient(120deg, #1d1d1f 30%, #0071e3 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-sub {
  margin: 22px auto 32px;
  max-width: 540px;
  font-size: clamp(17px, 2.4vw, 21px);
  color: var(--ink-soft);
}
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

.hero-visual { position: absolute; inset: 0; z-index: 1; pointer-events: none; }
.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(60px);
  opacity: 0.55;
  animation: float 14s ease-in-out infinite;
}
.orb-1 { width: 360px; height: 360px; background: #7fb2ff; top: 12%; left: 8%; }
.orb-2 { width: 300px; height: 300px; background: #ffb3c8; bottom: 8%; right: 10%; animation-delay: -4s; }
.orb-3 { width: 260px; height: 260px; background: #b8a8ff; top: 40%; right: 28%; animation-delay: -8s; }
@keyframes float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(20px, -28px) scale(1.08); }
}

.scroll-hint {
  position: absolute;
  bottom: 26px;
  left: 50%;
  transform: translateX(-50%);
  width: 22px;
  height: 34px;
  border: 1.5px solid var(--line);
  border-radius: 14px;
  z-index: 2;
}
.scroll-hint span {
  position: absolute;
  top: 7px;
  left: 50%;
  width: 3px;
  height: 7px;
  background: var(--ink-soft);
  border-radius: 2px;
  transform: translateX(-50%);
  animation: scrollDot 1.8s infinite;
}
@keyframes scrollDot {
  0% { opacity: 0; transform: translate(-50%, 0); }
  40% { opacity: 1; }
  100% { opacity: 0; transform: translate(-50%, 12px); }
}

/* ---------- 通用 section ---------- */
.section { padding: 110px 0; }
.section-alt { background: var(--bg-alt); }
.section-eyebrow {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 2px;
  color: var(--blue);
  text-align: center;
  margin-bottom: 12px;
}
.section-title {
  font-size: clamp(30px, 5vw, 48px);
  font-weight: 700;
  letter-spacing: -0.02em;
  text-align: center;
  line-height: 1.1;
}
.section-lead {
  max-width: 640px;
  margin: 22px auto 0;
  text-align: center;
  font-size: 19px;
  color: var(--ink-soft);
}

/* ---------- 数据 ---------- */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 64px;
}
.stat { text-align: center; }
.stat-num {
  display: block;
  font-size: clamp(34px, 5vw, 52px);
  font-weight: 700;
  letter-spacing: -0.02em;
  background: linear-gradient(120deg, #1d1d1f, #0071e3);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.stat-label { font-size: 14px; color: var(--ink-soft); }

/* ---------- 网格 / 卡片 ---------- */
.grid { display: grid; gap: 22px; margin-top: 56px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 32px 26px;
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease);
}
.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 18px 40px rgba(0, 0, 0, 0.1);
}
.card-icon {
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  font-size: 22px;
  border-radius: 12px;
  background: var(--bg-alt);
  color: var(--blue);
  margin-bottom: 18px;
}
.card h3 { font-size: 19px; margin-bottom: 8px; }
.card p { font-size: 15px; color: var(--ink-soft); }

/* ---------- 作品 ---------- */
.works { display: grid; gap: 28px; margin-top: 56px; }
.work {
  border-radius: var(--radius);
  overflow: hidden;
  background: #fff;
  border: 1px solid var(--line);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease);
}
.work:hover {
  transform: translateY(-6px);
  box-shadow: 0 18px 40px rgba(0, 0, 0, 0.1);
}
.work-media { height: 280px; }
.work-a { background: linear-gradient(135deg, #667eea, #764ba2); }
.work-b { background: linear-gradient(135deg, #ff9a9e, #fecfef); }
.work-c { background: linear-gradient(135deg, #43e97b, #38f9d7); }
.work-text { padding: 24px 26px; }
.work-text h3 { font-size: 20px; margin-bottom: 6px; }
.work-text p { font-size: 15px; color: var(--ink-soft); }
.work-link { display: inline-block; margin-top: 14px; color: var(--blue); font-size: 15px; }
.work-link:hover { text-decoration: underline; }

/* ---------- 中英双语切换 ---------- */
.lang-zh .en { display: none; }
.lang-en .zh { display: none; }

/* ---------- 团队 ---------- */
.member { text-align: center; }
.avatar {
  width: 92px;
  height: 92px;
  border-radius: 50%;
  margin: 0 auto 16px;
  background: linear-gradient(135deg, var(--c1), var(--c2));
}
.member h3 { font-size: 17px; }
.member p { font-size: 13px; color: var(--ink-soft); margin-top: 4px; }

/* ---------- CTA ---------- */
.cta {
  padding: 120px 22px;
  text-align: center;
  background: radial-gradient(circle at 50% 0%, #eef4ff, #fff 60%);
}
.cta-title {
  font-size: clamp(32px, 6vw, 56px);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.08;
}
.cta-sub { margin: 18px auto 34px; font-size: 19px; color: var(--ink-soft); max-width: 480px; }
.cta-mail { margin-top: 18px; font-size: 14px; color: var(--ink-soft); }

/* ---------- 页脚 ---------- */
.footer { background: var(--bg-alt); border-top: 1px solid var(--line); padding: 28px 0; }
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 13px;
  color: var(--ink-soft);
}
.footer-logo { font-weight: 600; color: var(--ink); }
.footer-links { display: flex; gap: 20px; }
.footer-links a:hover { color: var(--ink); }

/* ---------- 滚动渐显 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}
.reveal.in { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 860px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .stats { grid-template-columns: repeat(2, 1fr); gap: 32px; }
}
@media (max-width: 640px) {
  .nav-links {
    position: fixed;
    top: var(--nav-h);
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: rgba(255, 255, 255, 0.96);
    -webkit-backdrop-filter: blur(20px);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--line);
    padding: 8px 22px 16px;
    transform: translateY(-120%);
    transition: transform 0.35s var(--ease);
  }
  .nav-links.open { transform: translateY(0); }
  .nav-links a { padding: 12px 0; border-bottom: 1px solid var(--line); font-size: 15px; }
  .nav-toggle { display: flex; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}