/* ============ 设计变量 ============ */
:root {
  --bg: #0b1020;
  --bg-alt: #0f1530;
  --surface: #141b38;
  --surface-2: #1a2244;
  --border: rgba(255, 255, 255, 0.08);
  --text: #e8ecf6;
  --muted: #9aa4c2;
  --brand: #6c8bff;
  --brand-2: #a855f7;
  --accent: #35d0ba;
  --grad: linear-gradient(120deg, #6c8bff 0%, #a855f7 55%, #35d0ba 100%);
  --radius: 16px;
  --radius-sm: 10px;
  --shadow: 0 20px 50px -20px rgba(0, 0, 0, 0.6);
  --max: 1140px;
  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);
}

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

html { scroll-behavior: smooth; scroll-padding-top: 84px; }

body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
h1, h2, h3, h4 { line-height: 1.2; letter-spacing: -0.01em; }

.container { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 24px; }

.eyebrow {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--brand);
  margin-bottom: 14px;
}

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

/* ============ 按钮 ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.98rem;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease),
    background 0.2s var(--ease), border-color 0.2s var(--ease);
  white-space: nowrap;
}
.btn-primary {
  background: var(--grad);
  color: #0b1020;
  box-shadow: 0 12px 30px -12px rgba(108, 139, 255, 0.7);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 18px 40px -12px rgba(108, 139, 255, 0.85); }
.btn-ghost { background: transparent; color: var(--text); border-color: var(--border); }
.btn-ghost:hover { border-color: var(--brand); color: #fff; transform: translateY(-2px); }
.btn-block { width: 100%; }

/* ============ 顶部导航 ============ */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  transition: background 0.3s var(--ease), border-color 0.3s var(--ease), backdrop-filter 0.3s;
  border-bottom: 1px solid transparent;
}
.site-header.scrolled {
  background: rgba(11, 16, 32, 0.8);
  backdrop-filter: blur(14px);
  border-bottom-color: var(--border);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 72px; }

.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; }
.brand-mark {
  display: grid; place-items: center;
  width: 34px; height: 34px;
  border-radius: 10px;
  background: var(--grad);
  color: #0b1020;
  font-size: 1.1rem;
}
.brand-name { font-size: 1.1rem; letter-spacing: -0.02em; }
.brand-name em { font-style: normal; font-weight: 500; color: var(--muted); font-size: 0.78rem; margin-left: 6px; }

.nav-links { display: flex; align-items: center; gap: 8px; }
.nav-links a {
  padding: 9px 16px;
  border-radius: 999px;
  color: var(--muted);
  font-weight: 500;
  transition: color 0.2s, background 0.2s;
}
.nav-links a:hover { color: #fff; background: rgba(255, 255, 255, 0.05); }
.nav-links .nav-cta {
  background: rgba(108, 139, 255, 0.14);
  color: #cdd7ff;
  border: 1px solid rgba(108, 139, 255, 0.3);
}
.nav-links .nav-cta:hover { background: rgba(108, 139, 255, 0.24); color: #fff; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: 0;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 24px; height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.3s var(--ease), opacity 0.2s;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============ Hero ============ */
.hero { position: relative; padding: 170px 0 90px; overflow: hidden; }
.hero-glow {
  position: absolute;
  top: -20%; left: 50%;
  transform: translateX(-50%);
  width: 900px; height: 900px;
  max-width: 130vw;
  background: radial-gradient(circle at center, rgba(108, 139, 255, 0.28), rgba(168, 85, 247, 0.14) 40%, transparent 68%);
  filter: blur(20px);
  z-index: 0;
  pointer-events: none;
}
.hero-inner { position: relative; z-index: 1; text-align: center; max-width: 780px; margin: 0 auto; }
.hero-title { font-size: clamp(2.4rem, 6vw, 4.2rem); font-weight: 800; margin-bottom: 22px; }
.hero-sub { font-size: clamp(1rem, 2.2vw, 1.2rem); color: var(--muted); max-width: 620px; margin: 0 auto 34px; }
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 66px;
  padding: 28px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.stat { text-align: center; }
.stat strong { display: block; font-size: clamp(1.7rem, 4vw, 2.4rem); font-weight: 800; }
.stat span { color: var(--muted); font-size: 0.9rem; }

/* ============ 通用区块 ============ */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }
.section-head { text-align: center; max-width: 640px; margin: 0 auto 56px; }
.section-head h2 { font-size: clamp(1.8rem, 4vw, 2.6rem); margin-bottom: 14px; }
.section-desc { color: var(--muted); }

.grid { display: grid; gap: 22px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* ============ 服务卡片 ============ */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 26px;
  transition: transform 0.28s var(--ease), border-color 0.28s var(--ease), box-shadow 0.28s var(--ease);
}
.card:hover { transform: translateY(-6px); border-color: rgba(108, 139, 255, 0.4); box-shadow: var(--shadow); }
.card-icon {
  width: 54px; height: 54px;
  display: grid; place-items: center;
  font-size: 1.6rem;
  border-radius: 14px;
  background: var(--surface-2);
  margin-bottom: 18px;
}
.card h3 { font-size: 1.2rem; margin-bottom: 10px; }
.card p { color: var(--muted); font-size: 0.96rem; }

/* ============ 优势 ============ */
.why-inner { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 56px; align-items: center; }
.why-text h2 { font-size: clamp(1.8rem, 4vw, 2.6rem); margin-bottom: 14px; }
.check-list { list-style: none; margin: 26px 0 32px; display: grid; gap: 14px; }
.check-list li { position: relative; padding-left: 34px; color: var(--text); }
.check-list li::before {
  content: "✓";
  position: absolute; left: 0; top: 1px;
  width: 22px; height: 22px;
  display: grid; place-items: center;
  border-radius: 50%;
  background: rgba(53, 208, 186, 0.16);
  color: var(--accent);
  font-size: 0.8rem; font-weight: 700;
}
.why-cards { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.mini-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 22px 20px;
  transition: transform 0.25s var(--ease), border-color 0.25s;
}
.mini-card:hover { transform: translateY(-4px); border-color: rgba(168, 85, 247, 0.4); }
.mini-card strong { display: block; font-size: 1.05rem; margin-bottom: 6px; }
.mini-card span { color: var(--muted); font-size: 0.9rem; }

/* ============ 流程 ============ */
.steps .step {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 24px;
  position: relative;
  overflow: hidden;
}
.step-no {
  font-size: 2.6rem;
  font-weight: 800;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  opacity: 0.9;
}
.step h3 { font-size: 1.15rem; margin: 8px 0 8px; }
.step p { color: var(--muted); font-size: 0.94rem; }

/* ============ 案例 ============ */
.work {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform 0.28s var(--ease), box-shadow 0.28s var(--ease);
}
.work:hover { transform: translateY(-6px); box-shadow: var(--shadow); }
.work-cover { height: 176px; position: relative; }
.cover-1 { background: linear-gradient(135deg, #6c8bff, #3b4fce); }
.cover-2 { background: linear-gradient(135deg, #a855f7, #6d28d9); }
.cover-3 { background: linear-gradient(135deg, #35d0ba, #2b8fb3); }
.work-cover::after {
  content: "";
  position: absolute; inset: 0;
  background: radial-gradient(circle at 30% 20%, rgba(255,255,255,0.35), transparent 55%);
  mix-blend-mode: overlay;
}
.work-body { padding: 24px 24px 28px; }
.tag {
  display: inline-block;
  font-size: 0.76rem;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 999px;
  background: rgba(108, 139, 255, 0.14);
  color: #b9c6ff;
  margin-bottom: 12px;
}
.work-body h3 { font-size: 1.18rem; margin-bottom: 8px; }
.work-body p { color: var(--muted); font-size: 0.94rem; }

/* ============ 联系 ============ */
.contact-card {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 48px;
  align-items: center;
  background: linear-gradient(160deg, var(--surface) 0%, var(--surface-2) 100%);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 52px;
  position: relative;
  overflow: hidden;
}
.contact-card::before {
  content: "";
  position: absolute; top: -50%; right: -10%;
  width: 400px; height: 400px;
  background: radial-gradient(circle, rgba(168, 85, 247, 0.25), transparent 70%);
  pointer-events: none;
}
.contact-text h2 { font-size: clamp(1.7rem, 4vw, 2.4rem); margin-bottom: 12px; position: relative; }
.contact-text p { color: var(--muted); position: relative; }
.contact-info {
  list-style: none;
  margin-top: 22px;
  display: grid;
  gap: 12px;
  position: relative;
}
.contact-info li { display: flex; align-items: center; gap: 12px; font-size: 0.98rem; }
.contact-info .ci-label {
  flex: none;
  min-width: 52px;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--brand);
  padding: 3px 10px;
  border-radius: 999px;
  background: rgba(108, 139, 255, 0.14);
  text-align: center;
}
.contact-info a { color: var(--text); transition: color 0.2s; }
.contact-info a:hover { color: var(--brand); }
.contact-form { display: grid; gap: 14px; position: relative; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.contact-form input, .contact-form textarea {
  width: 100%;
  background: rgba(11, 16, 32, 0.6);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 13px 16px;
  color: var(--text);
  font-size: 0.96rem;
  font-family: inherit;
  transition: border-color 0.2s, box-shadow 0.2s;
  resize: vertical;
}
.contact-form input::placeholder, .contact-form textarea::placeholder { color: #6b7699; }
.contact-form input:focus, .contact-form textarea:focus {
  outline: none;
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(108, 139, 255, 0.18);
}
.form-hint { font-size: 0.88rem; color: var(--accent); min-height: 1.2em; }

/* ============ 页脚 ============ */
.site-footer { border-top: 1px solid var(--border); background: var(--bg-alt); padding-top: 56px; }
.footer-inner { display: grid; grid-template-columns: 1.4fr 2fr; gap: 40px; padding-bottom: 40px; }
.footer-brand .brand-name { font-size: 1.1rem; font-weight: 800; }
.footer-brand p { color: var(--muted); margin-top: 14px; font-size: 0.94rem; }
.footer-cols { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.footer-cols h4 { font-size: 0.95rem; margin-bottom: 14px; }
.footer-cols a { display: block; color: var(--muted); font-size: 0.92rem; padding: 5px 0; transition: color 0.2s; }
.footer-cols a:hover { color: #fff; }
.footer-bottom {
  display: flex; justify-content: space-between; align-items: center;
  padding: 22px 24px; border-top: 1px solid var(--border);
  color: var(--muted); font-size: 0.86rem; flex-wrap: wrap; gap: 8px;
}

/* ============ 滚动显现动画 ============ */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.6s var(--ease), transform 0.6s var(--ease); }
.reveal.in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* ============ 响应式 ============ */
@media (max-width: 940px) {
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .why-inner { grid-template-columns: 1fr; gap: 36px; }
  .contact-card { grid-template-columns: 1fr; padding: 40px 32px; }
  .footer-inner { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 720px) {
  .nav-links {
    position: fixed;
    top: 72px; left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
    padding: 16px 24px 24px;
    background: rgba(11, 16, 32, 0.97);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--border);
    transform: translateY(-120%);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.32s var(--ease), opacity 0.25s, visibility 0.25s;
  }
  .nav-links.open { transform: translateY(0); opacity: 1; visibility: visible; }
  .nav-links a { padding: 12px 16px; }
  .nav-toggle { display: flex; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); gap: 24px 12px; }
  .section { padding: 70px 0; }
  .hero { padding: 140px 0 70px; }
}

@media (max-width: 480px) {
  .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .why-cards { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .footer-cols { grid-template-columns: 1fr 1fr; }
  .contact-card { padding: 32px 22px; }
}