/* ============================================
   摄状元®AI创影 - Base Layer v1.0
   Reset / Typography / Container / Utilities
   ============================================ */

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: var(--szy-fs-base, 16px); scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--szy-font, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif);
  font-size: var(--szy-fs-base, 16px);
  line-height: 1.6;
  color: var(--szy-text, #1A1A2E);
  background: var(--szy-bg, #FFFFFF);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--szy-red, #C41E3A); text-decoration: none; transition: color 0.3s ease; }
a:hover { color: var(--szy-red-dark, #9B1830); }
ul, ol { list-style: none; }
button, input, select, textarea { font-family: inherit; font-size: inherit; line-height: inherit; }
button { cursor: pointer; border: none; background: none; }
h1,h2,h3,h4,h5,h6 { font-weight: 700; line-height: 1.3; color: var(--szy-text, #1A1A2E); }
p { margin-bottom: 0; }
table { border-collapse: collapse; width: 100%; }

/* ── Container ── */
.container {
  width: 100%;
  max-width: var(--szy-max-w, 1200px);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--szy-pad, 24px);
  padding-right: var(--szy-pad, 24px);
}

/* ── Typography ── */
.text-center { text-align: center; }
.text-red { color: var(--szy-red, #C41E3A); }
.text-gold { color: var(--szy-gold, #D4A017); }
.text-muted { color: var(--szy-text-3, #8A8A9A); }
.text-white { color: var(--szy-text-inv, #FFFFFF); }

/* ── Section ── */
.section {
  padding: 80px 0;
}
.section-alt {
  padding: 80px 0;
  background: var(--szy-bg-alt, #F8F9FC);
}
.section-dark {
  padding: 80px 0;
  background: var(--szy-bg-alt, #F8F9FC);
}
.section-header {
  text-align: center;
  margin-bottom: 48px;
}
.section-header h2 {
  font-size: 32px;
  font-weight: 700;
  color: var(--szy-text, #1A1A2E);
  margin-bottom: 12px;
}
.section-header .subtitle {
  font-size: 16px;
  color: var(--szy-text-2, #4A4A5A);
  max-width: 680px;
  margin: 0 auto 16px;
  line-height: 1.6;
}
.section-header .divider {
  width: 48px;
  height: 3px;
  background: var(--szy-gradient-cta, linear-gradient(135deg, #C41E3A, #D4A017));
  border-radius: 2px;
  margin: 0 auto;
}

/* ── Grid Base ── */
.features-grid {
  display: grid;
  gap: 24px;
}

/* ── Scroll Animation ── */
.fade-in-up {
  opacity: 1;
  transform: translateY(0);
}
.fade-in-up.visible {
  opacity: 1;
  transform: translateY(0);
}
.animate-in {
  opacity: 1;
  transform: translateY(0);
}
.animate-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── Utility ── */
.overflow-hidden { overflow: hidden; }
.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}

/* ══════════════════════════════════════════
   MOBILE (max-width: 767px)
   ══════════════════════════════════════════ */
@media (max-width: 767px) {
  .section, .section-alt, .section-dark { padding: 48px 0; }
  .section-header { margin-bottom: 32px; }
  .section-header h2 { font-size: 22px; }
  .section-header .subtitle { font-size: 14px; }
  .features-grid { gap: 16px; grid-template-columns: 1fr; }
}

/* ══════════════════════════════════════════
   TABLET (768px - 1023px)
   ══════════════════════════════════════════ */
@media (min-width: 768px) and (max-width: 1023px) {
  .section, .section-alt, .section-dark { padding: 56px 0; }
  .section-header { margin-bottom: 40px; }
  .section-header h2 { font-size: 28px; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ══════════════════════════════════════════
   DESKTOP (min-width: 1024px)
   ══════════════════════════════════════════ */
@media (min-width: 1024px) {
  .section { padding: 80px 0; }
  .section-alt, .section-dark { padding: 80px 0; }
  .section-header { margin-bottom: 48px; }
  .section-header h2 { font-size: 36px; }
  .section-header .subtitle { font-size: 18px; }
  .features-grid { grid-template-columns: repeat(3, 1fr); }
}