/* =========================================================================
   陕西智领远见科技 · Vivanpark — futuristic dark portal
   Brand tokens live in :root. Reuse var(--*) rather than hardcoding values.
   ========================================================================= */

:root {
  /* palette */
  --bg:        #05070d;
  --bg-2:      #080b14;
  --panel:     rgba(255, 255, 255, 0.035);
  --panel-2:   rgba(255, 255, 255, 0.06);
  --line:      rgba(255, 255, 255, 0.10);
  --line-soft: rgba(255, 255, 255, 0.06);

  --ink:       #eaf0ff;
  --ink-soft:  #aab4d4;
  --ink-faint: #6c7798;

  --accent:    #36e7ff;   /* cyan */
  --accent-2:  #8b5cff;   /* violet */
  --accent-3:  #2bd6a7;   /* mint, sparing use */
  --grad:      linear-gradient(110deg, var(--accent) 0%, var(--accent-2) 100%);
  --glow:      0 0 0 1px rgba(54,231,255,.10), 0 18px 50px -18px rgba(54,231,255,.35);

  /* type */
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", -apple-system,
          BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

  /* layout */
  --maxw: 1160px;
  --pad:  clamp(20px, 5vw, 48px);
  --radius:    18px;
  --radius-lg: 26px;
  --ease: cubic-bezier(.22, 1, .36, 1);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.7;
  letter-spacing: .01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3 { line-height: 1.18; letter-spacing: -.01em; margin: 0; font-weight: 700; }
p { margin: 0; }
a { color: inherit; text-decoration: none; }
ul, ol { margin: 0; padding: 0; list-style: none; }
img, svg { display: block; }

.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--pad); }

.grad {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.skip-link {
  position: fixed; top: -100px; left: 16px; z-index: 200;
  background: var(--accent); color: #04121a; padding: 10px 16px;
  border-radius: 10px; font-weight: 600; transition: top .2s var(--ease);
}
.skip-link:focus { top: 16px; }

/* ---------------------------------------------------------------- background */
.bg-field { position: fixed; inset: 0; z-index: -1; overflow: hidden; background: radial-gradient(120% 120% at 50% -10%, var(--bg-2), var(--bg) 60%); }

.bg-grid {
  position: absolute; inset: -2px;
  background-image:
    linear-gradient(to right, rgba(255,255,255,.045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255,255,255,.045) 1px, transparent 1px);
  background-size: 64px 64px;
  -webkit-mask-image: radial-gradient(120% 80% at 50% 0%, #000 30%, transparent 75%);
          mask-image: radial-gradient(120% 80% at 50% 0%, #000 30%, transparent 75%);
}

.bg-aurora { position: absolute; border-radius: 50%; filter: blur(80px); opacity: .5; will-change: transform; }
.aurora-1 { width: 52vw; height: 52vw; left: -12vw; top: -14vw; background: radial-gradient(circle, rgba(54,231,255,.55), transparent 65%); animation: drift1 22s var(--ease) infinite alternate; }
.aurora-2 { width: 46vw; height: 46vw; right: -10vw; top: 6vw;  background: radial-gradient(circle, rgba(139,92,255,.50), transparent 65%); animation: drift2 26s var(--ease) infinite alternate; }
.aurora-3 { width: 38vw; height: 38vw; left: 30vw; top: 60vh; background: radial-gradient(circle, rgba(43,214,167,.30), transparent 65%); animation: drift3 30s var(--ease) infinite alternate; }

.bg-noise { position: absolute; inset: 0; opacity: .035; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E"); }

@keyframes drift1 { to { transform: translate3d(6vw, 4vw, 0) scale(1.12); } }
@keyframes drift2 { to { transform: translate3d(-5vw, 5vw, 0) scale(1.08); } }
@keyframes drift3 { to { transform: translate3d(4vw, -6vw, 0) scale(1.15); } }

/* ---------------------------------------------------------------- header/nav */
.site-header { position: sticky; top: 0; z-index: 100; backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px); background: rgba(5,7,13,.55); border-bottom: 1px solid var(--line-soft); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 70px; }

.brand { display: inline-flex; align-items: center; gap: 12px; }
.brand-mark { display: grid; place-items: center; width: 40px; height: 40px; border-radius: 12px; background: var(--panel); border: 1px solid var(--line); box-shadow: var(--glow); }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-text strong { font-size: 1.05rem; letter-spacing: .04em; }
.brand-text em { font-style: normal; font-size: .62rem; letter-spacing: .42em; color: var(--ink-faint); }

.site-nav { display: flex; align-items: center; }
.nav-list { display: flex; align-items: center; gap: 6px; }
.nav-list a { display: inline-block; padding: 9px 14px; font-size: .92rem; color: var(--ink-soft); border-radius: 10px; transition: color .2s var(--ease), background .2s var(--ease); }
.nav-list a:hover { color: var(--ink); background: var(--panel); }
.nav-cta { color: var(--ink) !important; border: 1px solid var(--line); background: var(--panel); }
.nav-cta:hover { box-shadow: var(--glow); border-color: rgba(54,231,255,.4); }

.nav-toggle { display: none; flex-direction: column; gap: 5px; width: 44px; height: 44px; padding: 11px; background: var(--panel); border: 1px solid var(--line); border-radius: 12px; cursor: pointer; }
.nav-toggle span { height: 2px; width: 100%; background: var(--ink); border-radius: 2px; transition: transform .25s var(--ease), opacity .25s var(--ease); }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------------------------------------------------------------- buttons */
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 13px 24px; border-radius: 999px; font-weight: 600; font-size: .95rem; cursor: pointer; border: 1px solid transparent; transition: transform .25s var(--ease), box-shadow .25s var(--ease), background .25s var(--ease); }
.btn span { transition: transform .25s var(--ease); }
.btn:hover span { transform: translateX(4px); }
.btn-primary { background: var(--grad); color: #04121a; box-shadow: 0 14px 34px -12px rgba(54,231,255,.6); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 20px 44px -12px rgba(139,92,255,.65); }
.btn-ghost { background: var(--panel); border-color: var(--line); color: var(--ink); }
.btn-ghost:hover { border-color: rgba(54,231,255,.4); background: var(--panel-2); }
.btn-block { width: 100%; justify-content: center; }

/* ---------------------------------------------------------------- hero */
.hero { position: relative; padding: clamp(70px, 12vw, 130px) 0 clamp(40px, 6vw, 70px); }
.hero-inner { max-width: 880px; }
.eyebrow { font-size: .8rem; letter-spacing: .28em; text-transform: uppercase; color: var(--accent); margin-bottom: 22px; }
.hero-title { font-size: clamp(2.6rem, 7vw, 5rem); font-weight: 800; letter-spacing: -.02em; }
.hero-sub { margin-top: 26px; font-size: clamp(1rem, 1.6vw, 1.18rem); color: var(--ink-soft); max-width: 640px; }
.hero-sub-en { margin-top: 12px; font-size: .92rem; color: var(--ink-faint); letter-spacing: .02em; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 38px; }

.hero-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: clamp(48px, 7vw, 80px); padding: 28px; border: 1px solid var(--line); border-radius: var(--radius-lg); background: var(--panel); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); }
.hero-stats li { text-align: left; }
.hero-stats strong { display: block; font-size: clamp(1.8rem, 3.4vw, 2.6rem); font-weight: 800; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; font-variant-numeric: tabular-nums; }
.hero-stats span { font-size: .85rem; color: var(--ink-soft); }
.hero-stats em { display: block; font-style: normal; font-size: .68rem; letter-spacing: .12em; color: var(--ink-faint); text-transform: uppercase; }

/* ---------------------------------------------------------------- sections */
.section { padding: clamp(64px, 10vw, 120px) 0; }
.section-tag { font-size: .78rem; letter-spacing: .26em; text-transform: uppercase; color: var(--accent); margin-bottom: 16px; }
.section-title { font-size: clamp(1.7rem, 4vw, 2.9rem); font-weight: 800; }
.section-lead { margin-top: 20px; font-size: clamp(1rem, 1.5vw, 1.12rem); color: var(--ink-soft); max-width: 600px; }
.section-lead.center { margin-inline: auto; }
.section-body { margin-top: 18px; color: var(--ink-faint); max-width: 600px; }
.section-head { max-width: 720px; margin-bottom: clamp(40px, 6vw, 64px); }
.section-head.center, .section-head .center { text-align: center; }

.grid-2 { display: grid; grid-template-columns: 1.05fr .95fr; gap: clamp(32px, 6vw, 72px); align-items: center; }
.grid-2.reverse { grid-template-columns: .95fr 1.05fr; }

/* value cards (about) */
.value-cards { display: grid; gap: 14px; }
.value-cards li { padding: 22px 24px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); transition: transform .3s var(--ease), border-color .3s var(--ease); }
.value-cards li:hover { transform: translateX(6px); border-color: rgba(54,231,255,.35); }
.value-cards h3 { font-size: 1.02rem; margin-bottom: 6px; }
.value-cards p { color: var(--ink-soft); font-size: .94rem; }

/* services */
.service-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.service-card { position: relative; padding: 34px 32px; border: 1px solid var(--line); border-radius: var(--radius-lg); background: linear-gradient(180deg, var(--panel-2), var(--panel)); overflow: hidden; transition: transform .35s var(--ease), border-color .35s var(--ease), box-shadow .35s var(--ease); }
.service-card::before { content: ""; position: absolute; inset: 0; background: radial-gradient(80% 60% at 100% 0%, rgba(139,92,255,.16), transparent 60%); opacity: 0; transition: opacity .35s var(--ease); }
.service-card:hover { transform: translateY(-6px); border-color: rgba(54,231,255,.4); box-shadow: var(--glow); }
.service-card:hover::before { opacity: 1; }
.service-num { font-size: .85rem; letter-spacing: .2em; color: var(--accent); font-weight: 700; }
.service-card h3 { margin-top: 14px; font-size: 1.3rem; display: flex; flex-direction: column; gap: 4px; }
.service-card h3 em { font-style: normal; font-size: .76rem; letter-spacing: .1em; color: var(--ink-faint); font-weight: 500; }
.service-card p { margin-top: 14px; color: var(--ink-soft); font-size: .95rem; }
.chip-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.chip-row li { font-size: .76rem; padding: 5px 12px; border-radius: 999px; border: 1px solid var(--line); color: var(--ink-soft); background: var(--panel); }

/* steps / approach */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; counter-reset: step; }
.steps li { padding: 28px 24px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); position: relative; transition: transform .3s var(--ease), border-color .3s var(--ease); }
.steps li:hover { transform: translateY(-5px); border-color: rgba(139,92,255,.4); }
.step-index { font-size: 1.6rem; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; font-weight: 800; }
.steps h3 { margin-top: 12px; font-size: 1.08rem; }
.steps p { margin-top: 8px; font-size: .9rem; color: var(--ink-soft); }

/* strength */
.strength-list { display: grid; gap: 16px; }
.strength-list li { padding-left: 28px; position: relative; }
.strength-list li::before { content: ""; position: absolute; left: 0; top: 9px; width: 12px; height: 12px; border-radius: 3px; background: var(--grad); box-shadow: 0 0 14px rgba(54,231,255,.6); }
.strength-list h3 { font-size: 1.08rem; }
.strength-list p { margin-top: 4px; color: var(--ink-soft); font-size: .95rem; }

/* contact */
.contact-card { display: grid; grid-template-columns: 1.1fr .9fr; gap: clamp(32px, 5vw, 60px); padding: clamp(34px, 5vw, 56px); border: 1px solid var(--line); border-radius: var(--radius-lg); background: linear-gradient(160deg, var(--panel-2), var(--panel)); box-shadow: var(--glow); }
.contact-mail { display: inline-flex; flex-direction: column; gap: 4px; margin-top: 30px; padding: 18px 24px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--panel); transition: border-color .3s var(--ease), transform .3s var(--ease); width: fit-content; }
.contact-mail:hover { border-color: rgba(54,231,255,.45); transform: translateY(-2px); }
.contact-mail-label { font-size: .72rem; letter-spacing: .18em; text-transform: uppercase; color: var(--ink-faint); }
.contact-mail-value { font-size: 1.2rem; font-weight: 700; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }

.contact-form { display: grid; gap: 14px; align-content: start; }
.field { display: grid; gap: 7px; }
.field label { font-size: .82rem; color: var(--ink-soft); letter-spacing: .04em; }
.field input, .field textarea { width: 100%; padding: 13px 16px; border-radius: 12px; border: 1px solid var(--line); background: rgba(0,0,0,.25); color: var(--ink); font: inherit; font-size: .95rem; transition: border-color .2s var(--ease), box-shadow .2s var(--ease); }
.field input::placeholder, .field textarea::placeholder { color: var(--ink-faint); }
.field input:focus, .field textarea:focus { outline: none; border-color: rgba(54,231,255,.5); box-shadow: 0 0 0 3px rgba(54,231,255,.14); }
.field textarea { resize: vertical; min-height: 96px; }
.form-note { font-size: .86rem; min-height: 1.2em; }
.form-note.ok { color: var(--accent-3); }
.form-note.err { color: #ff8593; }

/* ---------------------------------------------------------------- footer */
.site-footer { border-top: 1px solid var(--line-soft); margin-top: 40px; padding: 56px 0 36px; background: rgba(5,7,13,.6); }
.footer-inner { display: flex; flex-wrap: wrap; gap: 28px 40px; justify-content: space-between; align-items: flex-start; }
.footer-brand { display: grid; gap: 4px; }
.footer-brand strong { font-size: 1.02rem; }
.footer-brand span { font-size: .82rem; color: var(--ink-faint); }
.footer-nav { display: flex; flex-wrap: wrap; gap: 8px 22px; }
.footer-nav a { font-size: .9rem; color: var(--ink-soft); transition: color .2s var(--ease); }
.footer-nav a:hover { color: var(--ink); }
.footer-meta { display: grid; gap: 4px; text-align: right; font-size: .88rem; color: var(--ink-soft); }
.footer-meta a:hover { color: var(--accent); }
.footer-bottom { display: flex; flex-wrap: wrap; gap: 8px 24px; justify-content: space-between; margin-top: 40px; padding-top: 24px; border-top: 1px solid var(--line-soft); font-size: .82rem; color: var(--ink-faint); }
.footer-tagline { color: var(--ink-soft); }

/* ---------------------------------------------------------------- reveal */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.reveal.in { opacity: 1; transform: none; }

/* ---------------------------------------------------------------- responsive */
@media (max-width: 920px) {
  .grid-2, .grid-2.reverse { grid-template-columns: 1fr; }
  .grid-2.reverse > *:first-child { order: 2; }
  .service-grid { grid-template-columns: 1fr; }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .contact-card { grid-template-columns: 1fr; }
  .footer-meta { text-align: left; }
}

@media (max-width: 720px) {
  .nav-toggle { display: flex; }
  .nav-list {
    position: absolute; top: 70px; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 4px;
    padding: 14px var(--pad) 22px;
    background: rgba(5,7,13,.96); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--line);
    transform: translateY(-12px); opacity: 0; pointer-events: none;
    transition: transform .28s var(--ease), opacity .28s var(--ease);
  }
  .nav-list.open { transform: none; opacity: 1; pointer-events: auto; }
  .nav-list a { padding: 13px 14px; font-size: 1rem; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); gap: 22px; }
}

@media (max-width: 420px) {
  .steps { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .btn:hover span { transform: none; }
}