/* =========================================================
   深海源海参 · 品牌官网样式表
   主色：深海蓝 / 纯净白，点缀雅金
   ========================================================= */

/* ---------- 设计变量 ---------- */
:root {
  --ink: #0a2342;          /* 深海墨蓝 */
  --ink-2: #13315c;        /* 次深蓝 */
  --brand: #1a6ed8;        /* 主蓝 */
  --brand-600: #1559b0;
  --brand-100: #e8f1fd;
  --sky: #f4f9ff;          /* 极浅蓝底 */
  --white: #ffffff;
  --line: #e3ecf7;
  --text: #33445c;
  --muted: #7b8ca4;
  --gold: #c8a45c;         /* 点缀金 */

  --radius: 18px;
  --radius-sm: 12px;
  --shadow: 0 12px 34px rgba(10, 35, 66, .08);
  --shadow-lg: 0 22px 60px rgba(10, 35, 66, .14);
  --ease: cubic-bezier(.22, .61, .36, 1);
  --nav-h: 74px;
  --max: 1200px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--white);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  font-size: 16px;
}

/* 标题使用衬线字体，提升气质 */
h1, h2, h3, h4, .serif {
  font-family: "Songti SC", "Source Han Serif SC", "Noto Serif SC", "STSong", "SimSun", serif;
  color: var(--ink);
  font-weight: 600;
  line-height: 1.35;
}

a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
button, input, textarea, select { font-family: inherit; font-size: inherit; outline: none; }
ul { list-style: none; }

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

/* ---------- 通用组件 ---------- */
.section { padding: 104px 0; position: relative; }
.section--tint { background: var(--sky); }

.sec-head { text-align: center; max-width: 720px; margin: 0 auto 58px; }
.sec-tag {
  display: inline-block;
  font-size: 13px;
  letter-spacing: .22em;
  color: var(--brand);
  background: var(--brand-100);
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 18px;
  text-transform: uppercase;
}
.sec-title { font-size: clamp(28px, 3.6vw, 42px); letter-spacing: .04em; }
.sec-title .accent { color: var(--brand); }
.sec-desc { margin-top: 16px; color: var(--muted); font-size: 16px; }
.sec-head .wave-line { margin: 20px auto 0; display: block; }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 30px;
  border-radius: 100px;
  font-size: 15px;
  font-weight: 500;
  letter-spacing: .05em;
  border: 1px solid transparent;
  cursor: pointer;
  transition: all .35s var(--ease);
  white-space: nowrap;
}
.btn--primary {
  background: linear-gradient(120deg, var(--brand) 0%, var(--brand-600) 100%);
  color: #fff;
  box-shadow: 0 10px 24px rgba(26, 110, 216, .28);
}
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 16px 32px rgba(26, 110, 216, .36); }
.btn--ghost { border-color: rgba(255, 255, 255, .55); color: #fff; }
.btn--ghost:hover { background: rgba(255, 255, 255, .14); transform: translateY(-2px); }
.btn--outline { border-color: var(--brand); color: var(--brand); }
.btn--outline:hover { background: var(--brand); color: #fff; transform: translateY(-2px); }
.btn--block { width: 100%; }

/* 滚动入场动画 */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .8s var(--ease), transform .8s var(--ease); }
.reveal.in { opacity: 1; transform: none; }

/* =========================================================
   顶部导航
   ========================================================= */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  z-index: 100;
  transition: background .4s var(--ease), box-shadow .4s var(--ease), height .35s var(--ease);
}
.nav--transparent { background: linear-gradient(180deg, rgba(6, 24, 48, .55), rgba(6, 24, 48, 0)); }
.nav--solid {
  background: rgba(255, 255, 255, .92);
  backdrop-filter: saturate(180%) blur(14px);
  box-shadow: 0 6px 24px rgba(10, 35, 66, .07);
  height: 66px;
}
.nav__inner { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 24px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }

.logo { display: flex; align-items: center; gap: 11px; }
.logo__mark { width: 38px; height: 38px; flex: none; }
.logo__text { display: flex; flex-direction: column; line-height: 1.15; }
.logo__cn { font-family: "Songti SC", "Source Han Serif SC", serif; font-size: 19px; font-weight: 700; letter-spacing: .1em; }
.logo__en { font-size: 10px; letter-spacing: .28em; opacity: .62; text-transform: uppercase; }
.nav:not(.nav--solid) .logo__cn { color: #fff; }
.nav:not(.nav--solid) .logo__en { color: rgba(255, 255, 255, .72); }
.nav--solid .logo__cn { color: var(--ink); }
.nav--solid .logo__en { color: var(--muted); }

.nav__menu { display: flex; align-items: center; gap: 6px; }
.nav__link {
  position: relative;
  padding: 8px 14px;
  font-size: 15px;
  border-radius: 8px;
  transition: color .3s var(--ease), background .3s var(--ease);
}
.nav:not(.nav--solid) .nav__link { color: rgba(255, 255, 255, .88); }
.nav:not(.nav--solid) .nav__link:hover { color: #fff; background: rgba(255, 255, 255, .12); }
.nav--solid .nav__link { color: var(--text); }
.nav--solid .nav__link:hover { color: var(--brand); background: var(--brand-100); }

.nav__actions { display: flex; align-items: center; gap: 12px; }
.nav__tel { font-size: 15px; font-weight: 600; letter-spacing: .04em; }
.nav:not(.nav--solid) .nav__tel { color: #fff; }
.nav--solid .nav__tel { color: var(--brand); }

.nav__toggle { display: none; width: 42px; height: 42px; border: 0; background: transparent; cursor: pointer; padding: 10px; }
.nav__toggle span { display: block; height: 2px; border-radius: 2px; background: #fff; transition: all .3s var(--ease); }
.nav__toggle span + span { margin-top: 6px; }
.nav--solid .nav__toggle span { background: var(--ink); }

/* =========================================================
   首屏 Hero
   ========================================================= */
.hero { position: relative; min-height: 100vh; display: flex; align-items: center; overflow: hidden; }
.hero__bg { position: absolute; inset: 0; }
.hero__bg img { width: 100%; height: 100%; object-fit: cover; }
.hero__mask {
  position: absolute; inset: 0;
  background: linear-gradient(100deg, rgba(6, 26, 54, .90) 0%, rgba(9, 38, 76, .72) 42%, rgba(10, 45, 90, .30) 72%, rgba(255, 255, 255, .12) 100%);
}
.hero__inner { position: relative; z-index: 2; width: 100%; max-width: var(--max); margin: 0 auto; padding: calc(var(--nav-h) + 40px) 24px 90px; }
.hero__content { max-width: 620px; color: #fff; }

.hero__badge {
  display: inline-flex; align-items: center; gap: 9px;
  padding: 7px 18px 7px 12px;
  border: 1px solid rgba(255, 255, 255, .3);
  border-radius: 100px;
  background: rgba(255, 255, 255, .1);
  backdrop-filter: blur(6px);
  font-size: 13px; letter-spacing: .12em;
  margin-bottom: 26px;
}
.hero__badge i { width: 6px; height: 6px; border-radius: 50%; background: #6ee7d0; display: inline-block; box-shadow: 0 0 0 4px rgba(110, 231, 208, .22); }

.hero__title {
  color: #fff;
  font-size: clamp(38px, 6.2vw, 68px);
  letter-spacing: .06em;
  text-shadow: 0 6px 30px rgba(0, 0, 0, .28);
}
.hero__title em { font-style: normal; color: #9fd4ff; }
.hero__sub {
  margin-top: 22px;
  font-size: clamp(15px, 1.6vw, 18px);
  color: rgba(255, 255, 255, .82);
  letter-spacing: .06em;
  max-width: 480px;
}
.hero__btns { margin-top: 38px; display: flex; flex-wrap: wrap; gap: 14px; }

.hero__scroll {
  position: absolute; left: 50%; bottom: 34px; transform: translateX(-50%);
  z-index: 3; display: flex; flex-direction: column; align-items: center; gap: 8px;
  color: rgba(255, 255, 255, .78); font-size: 12px; letter-spacing: .2em;
}
.hero__scroll .mouse {
  width: 22px; height: 34px; border: 1.5px solid rgba(255, 255, 255, .6); border-radius: 12px; position: relative;
}
.hero__scroll .mouse::after {
  content: ""; position: absolute; left: 50%; top: 7px; width: 3px; height: 7px; border-radius: 2px;
  background: rgba(255, 255, 255, .85); transform: translateX(-50%); animation: wheel 1.6s infinite;
}
@keyframes wheel { 0% { opacity: 0; transform: translate(-50%, 0); } 40% { opacity: 1; } 100% { opacity: 0; transform: translate(-50%, 11px); } }

/* 首屏右侧浮动信息卡 */
.hero__card {
  position: absolute; right: 5%; top: 50%; transform: translateY(-50%);
  z-index: 3; width: 268px;
  background: rgba(255, 255, 255, .93);
  backdrop-filter: blur(16px);
  border-radius: 20px;
  padding: 26px 24px;
  box-shadow: var(--shadow-lg);
  border: 1px solid rgba(255, 255, 255, .6);
}
.hero__card h4 { font-size: 17px; margin-bottom: 4px; }
.hero__card p { font-size: 13px; color: var(--muted); margin-bottom: 18px; }
.hero__card li { display: flex; align-items: center; gap: 10px; font-size: 14px; padding: 9px 0; border-top: 1px dashed var(--line); color: var(--text); }
.hero__card li:first-child { border-top: 0; }
.hero__card li b { margin-left: auto; color: var(--brand); font-weight: 600; }

/* ---------- 数据条 ---------- */
.stats { background: var(--ink); color: #fff; padding: 46px 0; }
.stats__grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.stat { text-align: center; padding: 8px 12px; position: relative; }
.stat + .stat::before {
  content: ""; position: absolute; left: 0; top: 50%; transform: translateY(-50%);
  width: 1px; height: 40px; background: rgba(255, 255, 255, .16);
}
.stat__num { font-family: "Songti SC", serif; font-size: 40px; color: #fff; letter-spacing: .02em; }
.stat__num span { font-size: 18px; margin-left: 3px; color: #9fd4ff; }
.stat__label { font-size: 13px; color: rgba(255, 255, 255, .62); letter-spacing: .14em; margin-top: 4px; }

/* =========================================================
   关于我们
   ========================================================= */
.about__grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 68px; align-items: center; }
.about__media { position: relative; }
.about__img { border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); }
.about__img img { width: 100%; height: 460px; object-fit: cover; transition: transform 1.2s var(--ease); }
.about__media:hover .about__img img { transform: scale(1.05); }
.about__exp {
  position: absolute; right: -26px; bottom: -26px;
  background: linear-gradient(130deg, var(--brand), var(--brand-600));
  color: #fff; border-radius: var(--radius);
  padding: 22px 26px; box-shadow: var(--shadow-lg); text-align: center;
}
.about__exp strong { display: block; font-family: "Songti SC", serif; font-size: 34px; line-height: 1.1; }
.about__exp span { font-size: 12px; letter-spacing: .18em; opacity: .82; }

.about__text p { color: var(--text); margin-bottom: 16px; }
.about__text .lead { font-size: 17px; color: var(--ink); }
.about__list { margin: 26px 0 32px; display: grid; gap: 14px; }
.about__list li { display: flex; gap: 13px; align-items: flex-start; }
.about__list .dot {
  flex: none; width: 22px; height: 22px; border-radius: 50%;
  background: var(--brand-100); color: var(--brand);
  display: grid; place-items: center; font-size: 12px; margin-top: 4px;
}
.about__list b { color: var(--ink); font-weight: 600; }
.about__list span { color: var(--muted); font-size: 14px; display: block; }

/* =========================================================
   原产地
   ========================================================= */
.origin { position: relative; padding: 110px 0 0; background: var(--ink); overflow: hidden; }
.origin__bg { position: absolute; inset: 0; }
.origin__bg img { width: 100%; height: 100%; object-fit: cover; opacity: .34; }
.origin__bg::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(8, 28, 56, .92) 0%, rgba(10, 40, 78, .80) 50%, rgba(244, 249, 255, .96) 100%);
}
.origin .container { position: relative; z-index: 2; }
.origin .sec-title { color: #fff; }
.origin .sec-desc { color: rgba(255, 255, 255, .7); }

.origin__grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; margin-bottom: -80px; }
.oc {
  background: rgba(255, 255, 255, .08);
  border: 1px solid rgba(255, 255, 255, .16);
  backdrop-filter: blur(10px);
  border-radius: var(--radius);
  padding: 30px 28px;
  color: rgba(255, 255, 255, .84);
  transition: transform .4s var(--ease), background .4s var(--ease);
}
.oc:hover { transform: translateY(-8px); background: rgba(255, 255, 255, .14); }
.oc__icon { width: 46px; height: 46px; margin-bottom: 18px; }
.oc h3 { color: #fff; font-size: 19px; margin-bottom: 10px; }
.oc p { font-size: 14.5px; }
.oc__meta { margin-top: 16px; padding-top: 14px; border-top: 1px solid rgba(255, 255, 255, .16); font-size: 13px; color: #9fd4ff; letter-spacing: .06em; }

/* 产地数据（浅色区，承接负边距） */
.origin__facts { background: var(--sky); padding: 130px 0 0; }
.facts { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.fact {
  background: #fff; border-radius: var(--radius-sm); padding: 26px 22px;
  box-shadow: var(--shadow); text-align: center;
}
.fact__k { font-size: 13px; color: var(--muted); letter-spacing: .1em; }
.fact__v { font-family: "Songti SC", serif; font-size: 26px; color: var(--brand); margin-top: 8px; }

/* =========================================================
   产品中心
   ========================================================= */
.tabs { display: flex; justify-content: center; gap: 10px; flex-wrap: wrap; margin-bottom: 44px; }
.tab {
  padding: 9px 22px; border-radius: 100px; border: 1px solid var(--line);
  background: #fff; color: var(--text); cursor: pointer; font-size: 14.5px;
  transition: all .3s var(--ease);
}
.tab:hover { border-color: var(--brand); color: var(--brand); }
.tab.active { background: var(--brand); border-color: var(--brand); color: #fff; box-shadow: 0 8px 20px rgba(26, 110, 216, .25); }

.products { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.pcard {
  background: #fff; border-radius: var(--radius); overflow: hidden;
  box-shadow: var(--shadow); border: 1px solid rgba(227, 236, 247, .8);
  display: flex; flex-direction: column;
  transition: transform .45s var(--ease), box-shadow .45s var(--ease);
}
.pcard:hover { transform: translateY(-10px); box-shadow: var(--shadow-lg); }
.pcard.hide { display: none; }

.pcard__media { position: relative; height: 218px; overflow: hidden; background: var(--brand-100); }
.pcard__media img { width: 100%; height: 100%; object-fit: cover; transition: transform 1s var(--ease); }
.pcard:hover .pcard__media img { transform: scale(1.07); }
.pcard__tag {
  position: absolute; left: 14px; top: 14px;
  background: rgba(10, 35, 66, .78); color: #fff;
  font-size: 12px; letter-spacing: .08em; padding: 5px 12px; border-radius: 100px;
  backdrop-filter: blur(4px);
}
.pcard__tag--gold { background: linear-gradient(120deg, #d8b46a, #b8913f); }
/* 定制卡：无实拍图时使用渐变 + 线描图形 */
.pcard__media--art {
  background: linear-gradient(140deg, #12457f 0%, #1a6ed8 60%, #4d9cf0 100%);
  display: grid; place-items: center;
}
.pcard__media--art svg { width: 62%; opacity: .9; }
.pcard__media--art .art-text {
  position: absolute; bottom: 18px; left: 0; right: 0; text-align: center;
  color: rgba(255, 255, 255, .9); font-size: 13px; letter-spacing: .2em;
}

.pcard__body { padding: 22px 22px 24px; display: flex; flex-direction: column; flex: 1; }
.pcard__name { font-size: 19px; margin-bottom: 8px; }
.pcard__desc { font-size: 14px; color: var(--muted); min-height: 48px; }
.pcard__spec { margin: 14px 0 16px; display: flex; flex-wrap: wrap; gap: 6px; }
.pcard__spec span { font-size: 12px; color: var(--brand-600); background: var(--brand-100); padding: 4px 10px; border-radius: 6px; }
.pcard__foot { margin-top: auto; display: flex; align-items: flex-end; justify-content: space-between; gap: 10px; }
.price { color: #d4302f; font-family: "Songti SC", serif; }
.price small { font-size: 15px; margin-right: 2px; }
.price b { font-size: 26px; font-weight: 700; }
.price del { display: block; font-size: 12px; color: var(--muted); font-family: inherit; }
.price .price__unit { display: block; font-size: 12px; color: var(--muted); font-family: inherit; }
.pcard__btn {
  border: 1px solid var(--brand); color: var(--brand); background: transparent;
  padding: 9px 18px; border-radius: 100px; cursor: pointer; font-size: 14px;
  transition: all .3s var(--ease);
}
.pcard__btn:hover { background: var(--brand); color: #fff; }

/* =========================================================
   工艺流程
   ========================================================= */
.process { background: var(--sky); }
.steps { display: grid; grid-template-columns: repeat(5, 1fr); gap: 18px; position: relative; }
.step { text-align: center; position: relative; padding: 0 8px; }
.step__no {
  width: 62px; height: 62px; margin: 0 auto 18px;
  border-radius: 50%; background: #fff; box-shadow: var(--shadow);
  display: grid; place-items: center;
  font-family: "Songti SC", serif; font-size: 22px; color: var(--brand);
  position: relative; z-index: 2;
}
.step + .step::before {
  content: ""; position: absolute; left: -9%; top: 31px; width: 118%; height: 1px;
  background: repeating-linear-gradient(90deg, #c3d8f2 0 6px, transparent 6px 12px);
  z-index: 1;
}
.step h4 { font-size: 17px; margin-bottom: 8px; }
.step p { font-size: 13.5px; color: var(--muted); }

/* =========================================================
   服务保障
   ========================================================= */
.promise { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.pitem {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 32px 26px; transition: all .4s var(--ease);
}
.pitem:hover { border-color: transparent; box-shadow: var(--shadow); transform: translateY(-6px); }
.pitem svg { width: 42px; height: 42px; margin-bottom: 16px; }
.pitem h4 { font-size: 17px; margin-bottom: 8px; }
.pitem p { font-size: 14px; color: var(--muted); }

/* =========================================================
   联系方式
   ========================================================= */
.contact { background: linear-gradient(160deg, #f4f9ff 0%, #ffffff 60%); }
.contact__grid { display: grid; grid-template-columns: .9fr 1.1fr; gap: 48px; align-items: start; }

.info-card {
  background: linear-gradient(150deg, var(--ink) 0%, var(--ink-2) 100%);
  color: #fff; border-radius: var(--radius); padding: 40px 36px; box-shadow: var(--shadow-lg);
}
.info-card h3 { color: #fff; font-size: 24px; margin-bottom: 6px; }
.info-card .tip { color: rgba(255, 255, 255, .6); font-size: 14px; margin-bottom: 28px; }
.info-list li { display: flex; gap: 16px; padding: 16px 0; border-top: 1px solid rgba(255, 255, 255, .12); }
.info-list li:first-child { border-top: 0; }
.info-list .ic {
  flex: none; width: 38px; height: 38px; border-radius: 10px;
  background: rgba(255, 255, 255, .1); display: grid; place-items: center;
}
.info-list .ic svg { width: 19px; height: 19px; }
.info-list .k { font-size: 12px; color: rgba(255, 255, 255, .55); letter-spacing: .14em; }
.info-list .v { font-size: 16px; color: #fff; }
.qr-row { display: flex; gap: 14px; margin-top: 26px; }
.qr {
  flex: 1; background: rgba(255, 255, 255, .07); border: 1px solid rgba(255, 255, 255, .14);
  border-radius: var(--radius-sm); padding: 14px; text-align: center;
}
.qr__box {
  width: 100%; aspect-ratio: 1; background: #fff; border-radius: 8px; margin-bottom: 8px;
  display: grid; place-items: center; color: var(--ink); font-size: 11px;
  background-image: linear-gradient(45deg, #eef4fb 25%, transparent 25%, transparent 75%, #eef4fb 75%),
                    linear-gradient(45deg, #eef4fb 25%, transparent 25%, transparent 75%, #eef4fb 75%);
  background-size: 12px 12px; background-position: 0 0, 6px 6px;
}
.qr__label { font-size: 12px; color: rgba(255, 255, 255, .7); }

.form-card { background: #fff; border-radius: var(--radius); padding: 40px; box-shadow: var(--shadow); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.field { margin-bottom: 18px; }
.field label { display: block; font-size: 14px; color: var(--ink); margin-bottom: 8px; }
.field label i { color: #d4302f; font-style: normal; margin-right: 3px; }
.field input, .field select, .field textarea {
  width: 100%; padding: 13px 16px; border: 1px solid var(--line); border-radius: var(--radius-sm);
  background: var(--sky); transition: all .3s var(--ease); color: var(--text);
}
.field input:focus, .field select:focus, .field textarea:focus {
  border-color: var(--brand); background: #fff; box-shadow: 0 0 0 4px rgba(26, 110, 216, .1);
}
.field textarea { min-height: 118px; resize: vertical; }
.form-note { font-size: 12.5px; color: var(--muted); margin-top: 12px; }
.form-ok {
  display: none; margin-top: 16px; padding: 12px 16px; border-radius: var(--radius-sm);
  background: #eaf7ef; color: #1f7a45; font-size: 14px; border: 1px solid #c7e9d4;
}
.form-ok.show { display: block; }
.form-err {
  display: none; margin-top: 16px; padding: 12px 16px; border-radius: var(--radius-sm);
  background: #fdecec; color: #c0392b; font-size: 14px; border: 1px solid #f3c6c6;
}
.form-err.show { display: block; }

/* =========================================================
   页脚
   ========================================================= */
.footer { background: var(--ink); color: rgba(255, 255, 255, .66); padding: 66px 0 0; }
.footer__grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1.2fr; gap: 40px; padding-bottom: 46px; }
.footer h4 { color: #fff; font-size: 17px; margin-bottom: 18px; }
.footer .f-logo { margin-bottom: 18px; }
.footer .f-logo .logo__cn { color: #fff; }
.footer .f-logo .logo__en { color: rgba(255, 255, 255, .5); }
.footer p { font-size: 14px; }
.footer ul li { padding: 7px 0; font-size: 14px; }
.footer ul li a:hover { color: #9fd4ff; }
.footer .contact-line { display: flex; align-items: center; gap: 10px; padding: 7px 0; font-size: 14px; }
.footer__bar {
  border-top: 1px solid rgba(255, 255, 255, .1); padding: 20px 0;
  display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; font-size: 13px;
  color: rgba(255, 255, 255, .45);
}

/* ---------- 浮动工具 ---------- */
.fab {
  position: fixed; right: 22px; z-index: 90;
  width: 50px; height: 50px; border-radius: 50%; border: 0; cursor: pointer;
  display: grid; place-items: center; box-shadow: var(--shadow-lg);
  transition: transform .3s var(--ease), opacity .3s var(--ease);
}
.fab:hover { transform: translateY(-4px); }
.fab--top { bottom: 96px; background: #fff; color: var(--ink); opacity: 0; pointer-events: none; }
.fab--top.show { opacity: 1; pointer-events: auto; }
.fab--tel { bottom: 32px; background: linear-gradient(130deg, var(--brand), var(--brand-600)); color: #fff; }
.fab svg { width: 21px; height: 21px; }

/* =========================================================
   响应式
   ========================================================= */
@media (max-width: 1080px) {
  .products { grid-template-columns: repeat(2, 1fr); }
  .origin__grid { grid-template-columns: 1fr; }
  .facts, .promise { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(3, 1fr); gap: 30px 18px; }
  .step + .step::before { display: none; }
  .footer__grid { grid-template-columns: 1fr 1fr; }
  .hero__card { display: none; }
}

@media (max-width: 860px) {
  .section { padding: 76px 0; }
  .nav__menu {
    position: fixed; inset: var(--nav-h) 0 auto 0; flex-direction: column; align-items: stretch;
    background: #fff; padding: 14px 24px 22px; gap: 2px;
    box-shadow: 0 18px 40px rgba(10, 35, 66, .14);
    transform: translateY(-14px); opacity: 0; pointer-events: none; transition: all .3s var(--ease);
  }
  .nav__menu.open { transform: none; opacity: 1; pointer-events: auto; }
  .nav__menu .nav__link { color: var(--text) !important; padding: 13px 10px; border-bottom: 1px solid var(--line); border-radius: 0; }
  .nav__menu .nav__link:hover { background: var(--sky); }
  .nav__toggle { display: block; }
  .nav__actions .btn { display: none; }
  .about__grid, .contact__grid { grid-template-columns: 1fr; gap: 40px; }
  .about__exp { right: 16px; bottom: -20px; }
  .origin__facts { padding-top: 150px; }
  .form-card, .info-card { padding: 30px 24px; }
  .stats__grid { grid-template-columns: repeat(2, 1fr); gap: 26px 0; }
  .stat:nth-child(3)::before, .stat:nth-child(odd)::before { display: none; }
}

@media (max-width: 620px) {
  .section { padding: 62px 0; }
  .container { padding: 0 18px; }
  .products { grid-template-columns: 1fr; }
  .facts, .promise { grid-template-columns: 1fr; }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .form-row { grid-template-columns: 1fr; }
  .footer__grid { grid-template-columns: 1fr; gap: 28px; }
  .footer__bar { justify-content: center; text-align: center; }
  .hero__sub { font-size: 15px; }
  .stat__num { font-size: 32px; }
}