/* ===== 主题变量 ===== */
:root {
  --green: #00b46e;
  --green-dark: #0a3d2c;
  --green-soft: #e7f7f0;
  --ink: #15241e;
  --muted: #5d6f68;
  --line: #e3ece8;
  --bg: #ffffff;
  --bg-alt: #f5faf7;
  --radius: 16px;
  --shadow: 0 10px 30px rgba(10, 61, 44, 0.08);
  --shadow-lg: 0 20px 50px rgba(10, 61, 44, 0.14);
  --maxw: 1180px;
  --nav-h: 68px;
  --font: "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
}

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

html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* ===== 通用 ===== */
.section { max-width: var(--maxw); margin: 0 auto; padding: 96px 24px; }
.section__head { text-align: center; max-width: 720px; margin: 0 auto 56px; }
.section__kicker {
  display: inline-block; font-size: 14px; font-weight: 700; letter-spacing: .12em;
  color: var(--green); text-transform: uppercase; margin-bottom: 12px;
}
.section__title { font-size: clamp(26px, 4vw, 40px); font-weight: 800; line-height: 1.25; }

.btn {
  display: inline-block; padding: 13px 28px; border-radius: 999px; font-weight: 700;
  font-size: 15px; cursor: pointer; border: 2px solid transparent; transition: .25s;
}
.btn--primary { background: var(--green); color: #fff; }
.btn--primary:hover { background: #009a5e; transform: translateY(-2px); box-shadow: var(--shadow); }
.btn--ghost { border-color: rgba(255,255,255,.6); color: #fff; }
.btn--ghost:hover { background: rgba(255,255,255,.12); border-color: #fff; }
.btn--block { width: 100%; }

/* ===== 导航 ===== */
.nav {
  position: fixed; top: 0; left: 0; right: 0; height: var(--nav-h); z-index: 100;
  background: rgba(255,255,255,.82); backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent; transition: .3s;
}
.nav.scrolled { border-color: var(--line); box-shadow: 0 4px 20px rgba(10,61,44,.06); }
.nav__inner {
  max-width: var(--maxw); margin: 0 auto; height: 100%; padding: 0 24px;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--green-dark); font-weight: 800; }
.brand__logo { color: var(--green); }
.brand__name { font-size: 19px; letter-spacing: .02em; }
.nav__menu { display: flex; gap: 30px; }
.nav__link { font-weight: 600; font-size: 15px; color: var(--ink); position: relative; padding: 6px 0; }
.nav__link::after {
  content: ""; position: absolute; left: 0; bottom: 0; height: 2px; width: 0; background: var(--green); transition: .25s;
}
.nav__link:hover, .nav__link.active { color: var(--green); }
.nav__link.active::after, .nav__link:hover::after { width: 100%; }

.nav__actions { display: flex; align-items: center; gap: 12px; }
.lang-toggle {
  border: 1.5px solid var(--line); background: #fff; color: var(--ink); border-radius: 999px;
  padding: 7px 14px; font-weight: 700; font-size: 13px; cursor: pointer; transition: .2s;
}
.lang-toggle:hover { border-color: var(--green); color: var(--green); }
.lang-toggle__cur { color: var(--green); }

.nav__burger { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 6px; }
.nav__burger span { width: 24px; height: 2px; background: var(--ink); border-radius: 2px; transition: .3s; }
.nav__burger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav__burger.open span:nth-child(2) { opacity: 0; }
.nav__burger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ===== Hero ===== */
.hero { position: relative; min-height: 100vh; display: flex; align-items: center; overflow: hidden; }
.hero__bg {
  position: absolute; inset: 0; z-index: 0;
  background:
    radial-gradient(900px 500px at 80% 10%, rgba(0,180,110,.22), transparent 60%),
    radial-gradient(700px 500px at 10% 90%, rgba(10,61,44,.18), transparent 60%),
    linear-gradient(135deg, #06281d 0%, #0a3d2c 45%, #06583b 100%);
}
.hero__bg::after {
  content: ""; position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.05) 1px, transparent 1px);
  background-size: 46px 46px; mask-image: radial-gradient(ellipse at 70% 40%, #000 30%, transparent 75%);
}
.hero__inner { position: relative; z-index: 1; max-width: var(--maxw); margin: 0 auto; padding: calc(var(--nav-h) + 40px) 24px 60px; color: #fff; width: 100%; }
.hero__eyebrow {
  display: inline-block; font-weight: 700; letter-spacing: .08em; font-size: 14px;
  color: #9affd0; background: rgba(0,180,110,.18); padding: 8px 16px; border-radius: 999px; margin-bottom: 22px;
}
.hero__title { font-size: clamp(34px, 6vw, 64px); font-weight: 900; line-height: 1.1; max-width: 760px; }
.hero__subtitle { font-size: clamp(15px, 2vw, 19px); color: rgba(255,255,255,.82); max-width: 620px; margin-top: 22px; }
.hero__tags { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 28px; }
.hero__tag {
  background: rgba(255,255,255,.1); border: 1px solid rgba(255,255,255,.22); color: #eafff5;
  padding: 8px 18px; border-radius: 999px; font-weight: 600; font-size: 14px; backdrop-filter: blur(4px);
}
.hero__cta { display: flex; gap: 16px; margin-top: 38px; flex-wrap: wrap; }

/* ===== 卡片网格 ===== */
.cards { display: grid; gap: 24px; }
.cards--4 { grid-template-columns: repeat(4, 1fr); }
.cards--3 { grid-template-columns: repeat(3, 1fr); }

.card {
  background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px; box-shadow: var(--shadow); transition: .3s;
}
.card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: rgba(0,180,110,.4); }
.card__icon {
  width: 56px; height: 56px; border-radius: 14px; display: grid; place-items: center;
  background: var(--green-soft); color: var(--green); margin-bottom: 18px;
}
.card__title { font-size: 19px; font-weight: 800; margin-bottom: 10px; }
.card__desc { color: var(--muted); font-size: 15px; }
.card__list { list-style: none; margin-top: 16px; display: grid; gap: 8px; }
.card__list li { position: relative; padding-left: 22px; font-size: 14px; color: var(--ink); }
.card__list li::before {
  content: ""; position: absolute; left: 0; top: 8px; width: 8px; height: 8px;
  border-radius: 50%; background: var(--green);
}

/* ===== 关于 ===== */
.about__intro { max-width: 820px; margin: -16px auto 48px; text-align: center; color: var(--muted); font-size: 17px; }

/* ===== 业务板块 ===== */
.biz-block { margin-top: 56px; }
.biz-block__head { display: flex; align-items: center; gap: 18px; margin-bottom: 28px; }
.biz-block__icon {
  width: 64px; height: 64px; border-radius: 18px; display: grid; place-items: center; color: #fff; flex: 0 0 auto;
}
.biz-block__icon--pv { background: linear-gradient(135deg, #00b46e, #0a8f5a); }
.biz-block__icon--es { background: linear-gradient(135deg, #1aa3ff, #0a6db0); }
.biz-block__icon--ev { background: linear-gradient(135deg, #ffb020, #f08a00); }
.biz-block__title { font-size: 24px; font-weight: 800; }
.biz-block__sub { color: var(--muted); font-size: 14px; margin-top: 2px; }

/* ===== 案例 ===== */
.card--proj { padding: 0; overflow: hidden; }
.card__media { height: 150px; }
.card__media--1 { background: linear-gradient(135deg, #0a8f5a, #00d286); }
.card__media--2 { background: linear-gradient(135deg, #0a6db0, #2bb6ff); }
.card__media--3 { background: linear-gradient(135deg, #f08a00, #ffc24d); }
.card__media--4 { background: linear-gradient(135deg, #0a3d2c, #00b46e); }
.card__body { padding: 22px 24px 26px; }
.card__tag {
  display: inline-block; font-size: 12px; font-weight: 700; color: var(--green);
  background: var(--green-soft); padding: 4px 12px; border-radius: 999px; margin-bottom: 12px;
}
.card__meta { color: var(--green); font-size: 13px; font-weight: 600; margin: 6px 0; }

/* ===== 数据 ===== */
.stats { background: linear-gradient(135deg, #06281d, #0a3d2c); color: #fff; }
.stats__inner { max-width: var(--maxw); margin: 0 auto; padding: 72px 24px; display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; text-align: center; }
.stat__num { font-size: clamp(36px, 5vw, 56px); font-weight: 900; color: #5dffb0; line-height: 1; }
.stat__label { margin-top: 12px; font-size: 15px; color: rgba(255,255,255,.8); }

/* ===== 联系 ===== */
.contact { background: var(--bg-alt); }
.contact__grid { display: grid; grid-template-columns: 1fr 1.2fr; gap: 48px; align-items: start; }
.contact__info { display: grid; gap: 24px; }
.contact__item { }
.contact__label { display: block; font-size: 13px; font-weight: 700; letter-spacing: .06em; color: var(--green); text-transform: uppercase; margin-bottom: 6px; }
.contact__item p { font-size: 16px; color: var(--ink); }

.contact__form { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; background: #fff; padding: 32px; border-radius: var(--radius); box-shadow: var(--shadow); }
.field { display: flex; flex-direction: column; gap: 7px; }
.field--full { grid-column: 1 / -1; }
.field label { font-size: 14px; font-weight: 600; }
.field input, .field select, .field textarea {
  font: inherit; padding: 12px 14px; border: 1.5px solid var(--line); border-radius: 10px;
  background: #fff; color: var(--ink); outline: none; transition: .2s; resize: vertical;
}
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--green); box-shadow: 0 0 0 3px rgba(0,180,110,.15); }
.field.invalid input, .field.invalid textarea { border-color: #e5484d; }
.field__err { font-size: 12px; color: #e5484d; display: none; }
.field.invalid .field__err { display: block; }

/* ===== 页脚 ===== */
.footer { background: #06281d; color: rgba(255,255,255,.78); padding: 56px 24px 24px; }
.footer__inner { max-width: var(--maxw); margin: 0 auto; display: flex; flex-wrap: wrap; gap: 32px; justify-content: space-between; align-items: flex-start; }
.footer__brand .brand__name { color: #fff; font-size: 20px; }
.footer__brand p { margin-top: 8px; color: rgba(255,255,255,.6); }
.footer__nav { display: flex; flex-direction: column; gap: 10px; }
.footer__nav a:hover { color: #5dffb0; }
.footer__social { display: flex; gap: 14px; }
.footer__social a { width: 38px; height: 38px; border-radius: 50%; display: grid; place-items: center; border: 1px solid rgba(255,255,255,.2); color: #fff; transition: .2s; }
.footer__social a:hover { background: var(--green); border-color: var(--green); }
.footer__bottom { max-width: var(--maxw); margin: 40px auto 0; padding-top: 20px; border-top: 1px solid rgba(255,255,255,.12); font-size: 13px; color: rgba(255,255,255,.5); }

/* ===== Toast ===== */
.toast {
  position: fixed; left: 50%; bottom: 32px; transform: translate(-50%, 20px);
  background: var(--green-dark); color: #fff; padding: 14px 26px; border-radius: 999px;
  font-weight: 600; box-shadow: var(--shadow-lg); opacity: 0; pointer-events: none; transition: .3s; z-index: 200;
}
.toast.show { opacity: 1; transform: translate(-50%, 0); }

/* ===== 滚动入场动画 ===== */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .7s ease, transform .7s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ===== 响应式 ===== */
@media (max-width: 980px) {
  .cards--4 { grid-template-columns: repeat(2, 1fr); }
  .stats__inner { grid-template-columns: repeat(2, 1fr); gap: 36px; }
  .contact__grid { grid-template-columns: 1fr; gap: 32px; }
}
@media (max-width: 760px) {
  .nav__menu {
    position: fixed; top: var(--nav-h); left: 0; right: 0; flex-direction: column; gap: 0;
    background: #fff; border-bottom: 1px solid var(--line); box-shadow: var(--shadow);
    max-height: 0; overflow: hidden; transition: max-height .35s ease;
  }
  .nav__menu.open { max-height: 320px; }
  .nav__menu .nav__link { padding: 16px 24px; border-bottom: 1px solid var(--line); }
  .nav__burger { display: flex; }
  .cards--3, .cards--4 { grid-template-columns: 1fr; }
  .section { padding: 64px 18px; }
  .contact__form { grid-template-columns: 1fr; padding: 24px; }
  .biz-block__head { flex-direction: row; }
}
@media (max-width: 460px) {
  .stats__inner { grid-template-columns: 1fr; }
}