/* ===========================================================
   上海与宁网络科技有限公司 · 知识产权官网
   极简 · 深蓝 / 白 · 科技专业风
   =========================================================== */

:root {
  --brand: #14366b;          /* 主品牌深蓝 */
  --brand-deep: #0d2747;     /* 更深蓝（页脚/深色区） */
  --brand-soft: #1e4a86;     /* 中蓝 */
  --accent: #3b82f6;         /* 亮蓝强调 */
  --accent-soft: #e8f0fe;    /* 浅蓝底 */

  --ink: #15233b;            /* 主文字 */
  --ink-soft: #5a6678;       /* 次要文字 */
  --ink-faint: #8a94a6;      /* 弱文字 */

  --bg: #ffffff;
  --bg-soft: #f6f8fb;        /* 浅灰区块底 */
  --bg-line: #e7ebf1;        /* 细线 */

  --radius: 14px;
  --radius-sm: 10px;
  --shadow-sm: 0 1px 2px rgba(16, 38, 73, .06);
  --shadow: 0 10px 30px rgba(16, 38, 73, .08);
  --shadow-lg: 0 24px 60px rgba(16, 38, 73, .14);

  --maxw: 1180px;
  --gap: clamp(64px, 8vw, 120px);

  --font: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB",
          "Helvetica Neue", Helvetica, Arial, system-ui, sans-serif;
}

/* ---------- reset ---------- */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }

/* ---------- layout ---------- */
.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }
.section { padding: var(--gap) 0; }
.section--soft { background: var(--bg-soft); }
.section--dark { background: var(--brand-deep); color: #fff; }

/* ---------- typography ---------- */
h1, h2, h3, h4 { line-height: 1.2; font-weight: 700; letter-spacing: -.01em; }
.eyebrow {
  display: inline-block;
  font-size: 13px; font-weight: 600; letter-spacing: .12em;
  text-transform: uppercase; color: var(--accent);
  margin-bottom: 14px;
}
.section-title { font-size: clamp(26px, 3.4vw, 40px); color: var(--ink); }
.section-title--light { color: #fff; }
.section-lead {
  margin-top: 16px; max-width: 640px;
  color: var(--ink-soft); font-size: 17px;
}
.center { text-align: center; }
.center .section-lead { margin-left: auto; margin-right: auto; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 26px; border-radius: 999px; font-weight: 600; font-size: 15px;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease, color .2s ease;
  white-space: nowrap;
}
.btn--primary { background: var(--brand); color: #fff; box-shadow: var(--shadow-sm); }
.btn--primary:hover { background: var(--brand-soft); transform: translateY(-2px); box-shadow: var(--shadow); }
.btn--accent { background: var(--accent); color: #fff; }
.btn--accent:hover { background: #2f6fd8; transform: translateY(-2px); }
.btn--ghost { border: 1px solid var(--bg-line); color: var(--ink); }
.btn--ghost:hover { border-color: var(--brand); color: var(--brand); }
.btn--light { background: #fff; color: var(--brand); }
.btn--light:hover { background: var(--accent-soft); }
.btn--lg { padding: 16px 34px; font-size: 16px; }

/* ---------- header ---------- */
.header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.86);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--bg-line);
}
.header__inner { display: flex; align-items: center; justify-content: space-between; height: 70px; }
.brand { display: flex; align-items: center; gap: 11px; font-weight: 700; }
.brand__mark {
  width: 34px; height: 34px; border-radius: 9px;
  background: linear-gradient(135deg, var(--brand), var(--accent));
  display: grid; place-items: center; color: #fff; font-size: 18px; font-weight: 800;
}
.brand__name { font-size: 18px; color: var(--ink); letter-spacing: .02em; }
.brand__name small { display: block; font-size: 11px; font-weight: 500; color: var(--ink-faint); letter-spacing: .18em; }

.nav { display: flex; align-items: center; gap: 4px; }
.nav a {
  padding: 9px 16px; border-radius: 8px; font-size: 15px; color: var(--ink-soft); font-weight: 500;
  transition: color .15s, background .15s;
}
.nav a:hover { color: var(--brand); background: var(--bg-soft); }
.nav a.active { color: var(--brand); background: var(--accent-soft); }
.header__phone { display: flex; align-items: center; gap: 8px; font-weight: 700; color: var(--brand); font-size: 15px; }
.header__phone svg { width: 17px; height: 17px; }
.nav-toggle { display: none; width: 42px; height: 42px; border-radius: 10px; border: 1px solid var(--bg-line); }
.nav-toggle span { display: block; width: 18px; height: 2px; background: var(--ink); margin: 3px auto; transition: .2s; }

/* ---------- hero ---------- */
.hero { position: relative; overflow: hidden; padding: clamp(70px, 11vw, 130px) 0 clamp(70px, 10vw, 120px); }
.hero::before {
  content: ""; position: absolute; inset: 0; z-index: 0;
  background:
    radial-gradient(900px 500px at 85% -10%, var(--accent-soft), transparent 60%),
    radial-gradient(700px 500px at -5% 110%, #eef3fb, transparent 55%);
}
.hero__grid { position: relative; z-index: 1; display: grid; grid-template-columns: 1.15fr .85fr; gap: 48px; align-items: center; }
.hero h1 { font-size: clamp(34px, 5vw, 58px); line-height: 1.1; }
.hero h1 .hl { color: var(--brand); }
.hero__sub { margin-top: 22px; font-size: 18px; color: var(--ink-soft); max-width: 520px; }
.hero__cta { margin-top: 34px; display: flex; gap: 14px; flex-wrap: wrap; }
.hero__tags { margin-top: 30px; display: flex; flex-wrap: wrap; gap: 10px; }
.hero__tags span {
  font-size: 13px; color: var(--ink-soft); background: #fff; border: 1px solid var(--bg-line);
  padding: 6px 13px; border-radius: 999px;
}

/* hero 视觉卡 */
.hero__visual { position: relative; }
.hero__card {
  background: #fff; border: 1px solid var(--bg-line); border-radius: 20px;
  padding: 30px; box-shadow: var(--shadow-lg); position: relative; z-index: 2;
}
.hero__card .row { display: flex; align-items: center; justify-content: space-between; padding: 16px 0; border-bottom: 1px dashed var(--bg-line); }
.hero__card .row:last-child { border-bottom: none; }
.hero__card .row .k { color: var(--ink-soft); font-size: 14px; }
.hero__card .row .v { font-weight: 700; color: var(--brand); }
.hero__badge {
  position: absolute; z-index: 3; top: -46px; right: 20px;
  background: var(--brand); color: #fff; border-radius: 14px; padding: 14px 18px;
  box-shadow: var(--shadow); text-align: center;
}
.hero__badge b { display: block; font-size: 24px; }
.hero__badge span { font-size: 12px; opacity: .85; }

/* ---------- stats ---------- */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.stat { text-align: center; padding: 8px; }
.stat__num { font-size: clamp(30px, 4vw, 46px); font-weight: 800; color: var(--brand); letter-spacing: -.02em; }
.stat__label { margin-top: 6px; color: var(--ink-soft); font-size: 15px; }
.section--dark .stat__num { color: #fff; }
.section--dark .stat__label { color: #c4d2e8; }

/* ---------- service grid ---------- */
.grid-cards { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; margin-top: 48px; }
.card {
  background: #fff; border: 1px solid var(--bg-line); border-radius: var(--radius);
  padding: 28px 24px; transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}
.card:hover { transform: translateY(-5px); box-shadow: var(--shadow); border-color: transparent; }
.card__icon {
  width: 46px; height: 46px; border-radius: 12px; background: var(--accent-soft);
  color: var(--brand); display: grid; place-items: center; margin-bottom: 16px;
}
.card__icon svg { width: 24px; height: 24px; }
.card h3 { font-size: 18px; }
.card p { margin-top: 8px; color: var(--ink-soft); font-size: 14.5px; }
.card__more { margin-top: 14px; display: inline-flex; align-items: center; gap: 6px; color: var(--brand); font-weight: 600; font-size: 14px; }
.card__more svg { width: 15px; height: 15px; transition: transform .2s; }
.card:hover .card__more svg { transform: translateX(4px); }

/* ---------- process ---------- */
.steps { display: grid; grid-template-columns: repeat(5, 1fr); gap: 18px; margin-top: 48px; counter-reset: step; }
.step { position: relative; padding: 26px 20px; border: 1px solid var(--bg-line); border-radius: var(--radius); background: #fff; }
.step::before {
  counter-increment: step; content: "0" counter(step);
  font-size: 30px; font-weight: 800; color: var(--accent-soft);
  display: block; margin-bottom: 12px;
}
.step h4 { font-size: 16px; }
.step p { margin-top: 6px; color: var(--ink-soft); font-size: 14px; }
.step:not(:last-child)::after {
  content: ""; position: absolute; top: 46px; right: -11px; width: 22px; height: 2px;
  background: var(--bg-line);
}

/* ---------- about / why ---------- */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.split__media {
  border-radius: 20px; min-height: 360px; padding: 40px;
  background: linear-gradient(150deg, var(--brand), var(--brand-deep));
  color: #fff; display: flex; flex-direction: column; justify-content: space-between;
}
.split__media h3 { font-size: 24px; }
.split__media ul { margin-top: 18px; display: grid; gap: 12px; }
.split__media li { display: flex; gap: 10px; align-items: flex-start; color: #d7e2f2; font-size: 15px; }
.split__media li b { color: #fff; }

.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin-top: 44px; }
.feature { padding: 26px; border-radius: var(--radius); background: #fff; border: 1px solid var(--bg-line); }
.feature__dot { width: 38px; height: 38px; border-radius: 10px; background: var(--accent-soft); display: grid; place-items: center; margin-bottom: 14px; color: var(--brand); font-weight: 800; }
.feature h4 { font-size: 17px; }
.feature p { margin-top: 8px; color: var(--ink-soft); font-size: 14.5px; }

/* ---------- industries ---------- */
.tags-cloud { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 36px; justify-content: center; }
.tags-cloud span {
  border: 1px solid var(--bg-line); background: #fff; padding: 10px 20px; border-radius: 999px;
  color: var(--ink-soft); font-size: 15px; transition: .2s;
}
.tags-cloud span:hover { border-color: var(--brand); color: var(--brand); }

/* ---------- CTA strip ---------- */
.cta-strip {
  background: linear-gradient(120deg, var(--brand), var(--brand-soft));
  border-radius: 22px; padding: clamp(36px, 5vw, 60px); color: #fff;
  display: flex; align-items: center; justify-content: space-between; gap: 30px; flex-wrap: wrap;
}
.cta-strip h2 { font-size: clamp(24px, 3vw, 34px); }
.cta-strip p { margin-top: 8px; color: #d2def0; }
.cta-strip__actions { display: flex; gap: 14px; flex-wrap: wrap; }

/* ---------- footer ---------- */
.footer { background: var(--brand-deep); color: #c4d2e8; padding: 64px 0 28px; }
.footer__grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1.2fr; gap: 40px; }
.footer a { color: #c4d2e8; transition: color .15s; }
.footer a:hover { color: #fff; }
.footer h4 { color: #fff; font-size: 15px; margin-bottom: 16px; letter-spacing: .04em; }
.footer__brand .brand__name { color: #fff; }
.footer__brand p { margin-top: 14px; font-size: 14px; line-height: 1.8; }
.footer__links li { margin-bottom: 10px; font-size: 14.5px; }
.footer__contact li { display: flex; gap: 10px; margin-bottom: 12px; font-size: 14.5px; align-items: flex-start; }
.footer__contact svg { width: 16px; height: 16px; flex: none; margin-top: 3px; color: var(--accent); }
.footer__bottom {
  margin-top: 48px; padding-top: 22px; border-top: 1px solid rgba(255,255,255,.12);
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; font-size: 13px; color: #93a6c4;
}

/* ---------- page hero (inner pages) ---------- */
.page-hero { background: linear-gradient(150deg, var(--brand-deep), var(--brand)); color: #fff; padding: clamp(56px, 8vw, 96px) 0; }
.page-hero h1 { font-size: clamp(30px, 4.4vw, 48px); }
.page-hero p { margin-top: 16px; color: #cdddf2; max-width: 620px; font-size: 17px; }
.breadcrumb { font-size: 13px; color: #9fb3d4; margin-bottom: 16px; }
.breadcrumb a:hover { color: #fff; }

/* ---------- service detail ---------- */
.svc-list { display: grid; gap: 22px; margin-top: 40px; }
.svc {
  display: grid; grid-template-columns: 64px 1fr; gap: 26px; align-items: start;
  padding: 32px; border: 1px solid var(--bg-line); border-radius: var(--radius); background: #fff;
  scroll-margin-top: 90px; transition: box-shadow .25s, border-color .25s;
}
.svc:hover { box-shadow: var(--shadow); border-color: transparent; }
.svc__no {
  width: 64px; height: 64px; border-radius: 16px; background: var(--accent-soft); color: var(--brand);
  display: grid; place-items: center; font-size: 26px; font-weight: 800;
}
.svc h3 { font-size: 21px; }
.svc__desc { margin-top: 8px; color: var(--ink-soft); }
.svc__items { margin-top: 16px; display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px 24px; }
.svc__items li { display: flex; gap: 10px; align-items: flex-start; font-size: 15px; }
.svc__items li svg { width: 17px; height: 17px; color: var(--accent); flex: none; margin-top: 4px; }

/* ---------- contact ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1.1fr; gap: 48px; align-items: start; }
.info-card { background: #fff; border: 1px solid var(--bg-line); border-radius: var(--radius); padding: 32px; box-shadow: var(--shadow-sm); }
.info-card h3 { font-size: 19px; margin-bottom: 6px; }
.info-card .muted { color: var(--ink-soft); font-size: 14px; margin-bottom: 20px; }
.info-list li { display: flex; gap: 14px; padding: 16px 0; border-bottom: 1px dashed var(--bg-line); align-items: flex-start; }
.info-list li:last-child { border-bottom: none; }
.info-list .ic { width: 40px; height: 40px; border-radius: 11px; background: var(--accent-soft); color: var(--brand); display: grid; place-items: center; flex: none; }
.info-list .ic svg { width: 20px; height: 20px; }
.info-list .k { font-size: 13px; color: var(--ink-faint); }
.info-list .v { font-size: 16px; font-weight: 600; color: var(--ink); }
.info-list a.v:hover { color: var(--brand); }

.form { background: #fff; border: 1px solid var(--bg-line); border-radius: var(--radius); padding: 32px; box-shadow: var(--shadow-sm); }
.form .field { margin-bottom: 18px; }
.form label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 8px; color: var(--ink); }
.form label .req { color: #e0483b; }
.form input, .form select, .form textarea {
  width: 100%; padding: 12px 14px; border: 1px solid var(--bg-line); border-radius: var(--radius-sm);
  font-family: inherit; font-size: 15px; color: var(--ink); background: #fff; transition: border .15s, box-shadow .15s;
}
.form input:focus, .form select:focus, .form textarea:focus {
  outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft);
}
.form textarea { resize: vertical; min-height: 110px; }
.form .row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form__note { font-size: 13px; color: var(--ink-faint); margin-top: 6px; }
.form__ok { display: none; margin-top: 16px; padding: 14px 16px; border-radius: var(--radius-sm); background: #eafaf1; color: #1f8a4d; font-size: 14.5px; border: 1px solid #c8efd6; }
.form__ok.show { display: block; }

.map-box {
  margin-top: 22px; border-radius: var(--radius); overflow: hidden; border: 1px solid var(--bg-line);
  height: 220px; background:
    linear-gradient(0deg, rgba(20,54,107,.04), rgba(20,54,107,.04)),
    repeating-linear-gradient(45deg, #eef2f8 0 12px, #f6f8fb 12px 24px);
  display: grid; place-items: center; text-align: center; color: var(--ink-soft);
}
.map-box a { color: var(--brand); font-weight: 600; }

/* ---------- polish: 焦点 / 选区 / 细节 ---------- */
::selection { background: var(--accent); color: #fff; }
a:focus-visible, button:focus-visible,
input:focus-visible, select:focus-visible, textarea:focus-visible {
  outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 6px;
}
.header.scrolled { box-shadow: 0 6px 24px rgba(16, 38, 73, .08); }
.card__icon { transition: transform .25s ease, background .25s ease, color .25s ease; }
.card:hover .card__icon { transform: translateY(-3px); background: var(--brand); color: #fff; }
.nav a { position: relative; }
.nav a::after {
  content: ""; position: absolute; left: 16px; right: 16px; bottom: 5px; height: 2px;
  background: var(--accent); transform: scaleX(0); transform-origin: left; transition: transform .2s ease;
}
.nav a:hover::after, .nav a.active::after { transform: scaleX(1); }
.section-title { position: relative; }
.section-title::before {
  content: ""; display: block; width: 44px; height: 3px; border-radius: 3px;
  background: var(--accent); margin-bottom: 16px;
}
.center .section-title::before { margin-left: auto; margin-right: auto; }

/* ---------- reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- responsive ---------- */
@media (max-width: 980px) {
  .hero__grid { grid-template-columns: 1fr; }
  .hero__visual { order: -1; max-width: 460px; }
  .stats { grid-template-columns: repeat(2, 1fr); gap: 32px 16px; }
  .grid-cards { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .step:not(:last-child)::after { display: none; }
  .split, .contact-grid { grid-template-columns: 1fr; gap: 32px; }
  .features { grid-template-columns: 1fr; }
  .footer__grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .svc__items { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  .nav, .header__phone { display: none; }
  .nav-toggle { display: block; }
  .header.open .nav {
    display: flex; flex-direction: column; align-items: stretch; gap: 2px;
    position: absolute; top: 70px; left: 0; right: 0; background: #fff;
    border-bottom: 1px solid var(--bg-line); padding: 12px 24px; box-shadow: var(--shadow);
  }
  .header.open .nav a { padding: 13px 14px; }
  .header.open .nav a.active { background: var(--accent-soft); }
  .grid-cards, .stats, .steps, .features, .footer__grid { grid-template-columns: 1fr; }
  .form .row2 { grid-template-columns: 1fr; }
  .cta-strip { flex-direction: column; align-items: flex-start; }
}