/* ===== 超市软件官网 · 前台样式 ===== */
:root {
  --brand: #16a34a;
  --brand-dark: #15803d;
  --brand-deep: #14532d;
  --teal: #0f766e;
  --ink: #1f2937;
  --ink-soft: #4b5563;
  --bg: #ffffff;
  --bg-alt: #f0fdf4;
  --line: #e5e7eb;
  --radius: 14px;
  --shadow: 0 8px 30px rgba(16, 60, 40, .10);
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
}
img { max-width: 100%; display: block; }
a { color: var(--brand-dark); text-decoration: none; }
.container { max-width: 1120px; margin: 0 auto; padding: 0 24px; }

/* 按钮 */
.btn {
  display: inline-block; padding: 10px 22px; border-radius: 10px;
  border: 1px solid transparent; cursor: pointer; font-size: 15px;
  transition: all .2s ease; text-align: center;
}
.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:hover { background: var(--brand-dark); transform: translateY(-1px); box-shadow: 0 6px 18px rgba(22,163,74,.35); }
.btn-ghost { background: transparent; color: #fff; border-color: rgba(255,255,255,.55); }
.btn-ghost:hover { background: rgba(255,255,255,.12); }
.btn-lg { padding: 14px 34px; font-size: 17px; }
.btn-sm { padding: 6px 14px; font-size: 13px; }
.btn[disabled] { opacity: .55; cursor: not-allowed; transform: none !important; box-shadow: none !important; }

/* 导航 */
.nav { position: sticky; top: 0; z-index: 50; background: rgba(255,255,255,.92); backdrop-filter: blur(8px); border-bottom: 1px solid var(--line); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; color: var(--ink); font-size: 18px; }
.brand-logo { width: 34px; height: 34px; }
.nav-links { display: flex; align-items: center; gap: 26px; }
.nav-links a:not(.btn) { color: var(--ink-soft); font-size: 15px; }
.nav-links a:not(.btn):hover { color: var(--brand-dark); }
.nav-toggle { display: none; background: none; border: none; font-size: 24px; cursor: pointer; color: var(--ink); }

/* 首页横幅 */
.hero { background: linear-gradient(135deg, var(--brand-deep) 0%, var(--brand) 60%, var(--teal) 100%); color: #fff; overflow: hidden; }
.hero-inner { display: grid; grid-template-columns: 1.1fr .9fr; gap: 40px; align-items: center; padding: 76px 24px 84px; }
.hero-text h1 { font-size: 44px; line-height: 1.25; margin-bottom: 18px; letter-spacing: .5px; }
.hero-sub { font-size: 18px; color: rgba(255,255,255,.88); white-space: pre-line; margin-bottom: 30px; }
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-visual img { border-radius: 16px; box-shadow: 0 20px 60px rgba(0,0,0,.25); }

/* 区块 */
.section { padding: 72px 0; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; margin-bottom: 44px; }
.section-head h2 { font-size: 30px; margin-bottom: 8px; }
.section-head p { color: var(--ink-soft); font-size: 16px; }

.grid { display: grid; gap: 22px; }
.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: 26px; box-shadow: var(--shadow); }
.feature-card { transition: transform .2s ease, box-shadow .2s ease; }
.feature-card:hover { transform: translateY(-4px); box-shadow: 0 16px 40px rgba(16,60,40,.16); }
.feature-icon { font-size: 34px; margin-bottom: 12px; }
.feature-card h3 { font-size: 18px; margin-bottom: 8px; }
.feature-card p { color: var(--ink-soft); font-size: 14.5px; }

/* 产品展示 */
.showcase-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.browser-frame { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.browser-frame::before {
  content: "● ● ●"; display: block; background: #f3f4f6; color: #9ca3af;
  font-size: 11px; letter-spacing: 3px; padding: 10px 16px; border-bottom: 1px solid var(--line);
}
.browser-frame img { aspect-ratio: 4/3; object-fit: cover; }
.browser-frame figcaption { padding: 12px 16px; font-size: 14px; color: var(--ink-soft); }

/* 下载区块 */
.section-download { background: linear-gradient(135deg, #f0fdf4, #ecfeff); }
.download-card { max-width: 760px; margin: 0 auto; background: #fff; border-radius: 18px; padding: 46px; text-align: center; box-shadow: var(--shadow); border: 1px solid var(--line); }
.download-info { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin-bottom: 22px; }
.version-tag { background: #ecfdf5; color: var(--brand-dark); border: 1px solid #a7f3d0; padding: 4px 14px; border-radius: 20px; font-size: 14px; }
.version-tag.dim { background: #f8fafc; color: var(--ink-soft); border-color: var(--line); }
.version-tag.warn { background: #fef2f2; color: #b91c1c; border-color: #fecaca; }
.btn-download { font-size: 19px; padding: 16px 44px; }
.download-note { color: var(--ink-soft); font-size: 14px; margin-top: 18px; }
.download-help { text-align: left; margin-top: 30px; padding-top: 24px; border-top: 1px dashed var(--line); }
.download-help h3 { font-size: 16px; margin-bottom: 10px; }
.download-help li { margin: 6px 0 6px 20px; color: var(--ink-soft); font-size: 14.5px; }

/* 联系我们 */
.contact-card { text-align: center; }
.contact-icon { font-size: 30px; margin-bottom: 10px; }
.contact-card h3 { font-size: 16px; margin-bottom: 6px; }
.contact-card p { color: var(--ink-soft); font-size: 14.5px; }

/* 在线留言表单 */
.contact-form-wrap { margin-top: 26px; display: flex; justify-content: center; }
.contact-form-card { max-width: 620px; width: 100%; padding: 30px 34px; }
.contact-form-card h3 { font-size: 20px; margin-bottom: 6px; text-align: center; }
.contact-form-tip { color: var(--ink-soft); font-size: 13.5px; text-align: center; margin-bottom: 20px; }
.contact-form .field { margin-bottom: 14px; }
.contact-form .field label { display: block; font-size: 14px; font-weight: 600; color: var(--ink-soft); margin-bottom: 6px; }
.contact-form .field input[type=text],
.contact-form .field input[type=tel],
.contact-form .field textarea {
  width: 100%; padding: 10px 13px; border: 1px solid var(--line); border-radius: 10px;
  font-size: 14.5px; font-family: inherit; color: var(--ink); background: #fff;
  transition: border-color .18s, box-shadow .18s;
}
.contact-form .field textarea { resize: vertical; }
.contact-form .field input:focus, .contact-form .field textarea:focus {
  outline: none; border-color: var(--brand); box-shadow: 0 0 0 3px rgba(22,163,74,.14);
}
.contact-form .field input::placeholder, .contact-form .field textarea::placeholder { color: #9ca3af; }
.btn-block { width: 100%; }
.honeypot { position: absolute; left: -9999px; height: 0; width: 0; opacity: 0; }

/* 提交结果提示（flash） */
.flash-wrap { max-width: 1120px; margin: 18px auto 0; padding: 0 24px; }
.flash { padding: 12px 16px; border-radius: 10px; font-size: 14.5px; margin-bottom: 10px; }
.flash-success { background: #ecfdf5; color: #15803d; border: 1px solid #bbf7d0; }
.flash-error { background: #fef2f2; color: #b91c1c; border: 1px solid #fecaca; }
.flash-warn { background: #fffbeb; color: #b45309; border: 1px solid #fde68a; }
.flash-info { background: #eff6ff; color: #1d4ed8; border: 1px solid #bfdbfe; }

/* 页脚 */
.footer { background: var(--brand-deep); color: rgba(255,255,255,.82); padding: 26px 0; font-size: 14px; }
.footer-inner { display: flex; justify-content: space-between; align-items: center; gap: 16px; flex-wrap: wrap; }
.footer-links a { color: rgba(255,255,255,.82); margin-left: 18px; }
.footer-links a:hover { color: #fff; }

/* 错误页 */
.error-page { min-height: 100vh; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 14px; background: var(--bg-alt); }
.error-page h1 { font-size: 72px; color: var(--brand); }
.error-page p { color: var(--ink-soft); }

@media (max-width: 900px) {
  .grid-3, .grid-4, .showcase-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-inner { grid-template-columns: 1fr; padding: 56px 24px 64px; }
  .hero-text h1 { font-size: 34px; }
}
@media (max-width: 620px) {
  .grid-3, .grid-4, .showcase-grid { grid-template-columns: 1fr; }
  .nav-links { display: none; position: absolute; top: 64px; left: 0; right: 0; background: #fff; flex-direction: column; padding: 18px 24px; border-bottom: 1px solid var(--line); gap: 16px; align-items: flex-start; }
  .nav-links.open { display: flex; }
  .nav-toggle { display: block; }
}