/* ==========================================================================
   nature-ui.css — 「听见生灵 · 看见守护」海报同风格浅色山水主题
   · 浅色通透底 + 山水/动植物实景 + 青绿点缀（#2fa98c 系）
   · 覆盖范围：典型案例 / 开启合作 / 公司简介 / 秀美课堂·知识问答
   · 本文件必须在 coop-section.css、company-intro.css、style.css 之后加载
   ========================================================================== */

:root {
  --nat-ink: #12332b;            /* 深松绿（标题） */
  --nat-body: #3d524b;           /* 正文 */
  --nat-accent: #2fa98c;         /* 青绿主强调 */
  --nat-accent-deep: #1f7f68;    /* 深一档强调 */
  --nat-mist: #f4fbf8;           /* 薄雾浅底 */
}

/* --------------------------------------------------------------------------
   1) 典型案例：暖色日落黑遮罩 → 浅色青绿山水湖景
   -------------------------------------------------------------------------- */
.destination-section.bg-overlay-dark-8::before {
  background:
    linear-gradient(180deg,
      rgba(247, 253, 250, 0.94) 0%,
      rgba(240, 250, 246, 0.82) 42%,
      rgba(236, 249, 244, 0.86) 100%);
}

.destination-section .section-title .title.text-white {
  color: var(--nat-ink) !important;
}

.destination-section .section-title .description p.text-white {
  color: var(--nat-body) !important;
}

/* --------------------------------------------------------------------------
   2) 开启合作：深蓝夜色 → 晨雾鹿林浅色主题
   -------------------------------------------------------------------------- */
.coop-section {
  background: var(--nat-mist);
  color: var(--nat-body);
}

.coop-bg {
  background-color: var(--nat-mist);
  background-image: url(../images/bg/nature-deer.jpg);
}

/* 白色薄雾蒙版：左重（文字区）右轻（鹿景透出），上下渐变保可读 */
.coop-bg::after {
  background:
    linear-gradient(94deg,
      rgba(244, 251, 248, 0.97) 0%,
      rgba(244, 251, 248, 0.9) 40%,
      rgba(244, 251, 248, 0.58) 72%,
      rgba(244, 251, 248, 0.4) 100%),
    linear-gradient(180deg,
      rgba(244, 251, 248, 0.55) 0%,
      rgba(244, 251, 248, 0.2) 34%,
      rgba(244, 251, 248, 0.72) 100%);
}

.coop-eyebrow {
  color: rgba(18, 51, 43, 0.5);
}

.coop-title {
  color: var(--nat-ink);
}

.coop-nav__item {
  color: rgba(18, 51, 43, 0.85);
}

.coop-nav__item::before {
  background: linear-gradient(180deg, #3cbb99, var(--nat-accent-deep));
}

.coop-contact {
  border-top: 1px solid rgba(18, 51, 43, 0.14);
}

.coop-contact li {
  color: rgba(18, 51, 43, 0.62);
}

.coop-contact i {
  color: var(--nat-accent);
}

/* --------------------------------------------------------------------------
   3) 公司简介：蓝色微光 → 青绿微光（与海报同色系）
   -------------------------------------------------------------------------- */
.company-intro {
  background:
    radial-gradient(1200px 620px at 82% 42%, rgba(47, 169, 140, 0.07), rgba(47, 169, 140, 0) 68%),
    linear-gradient(180deg, #ffffff 0%, #f2faf7 100%);
}

.company-intro .ci-tags span {
  color: var(--nat-accent-deep);
  background: rgba(47, 169, 140, 0.08);
  border: 1px solid rgba(47, 169, 140, 0.2);
}

/* --------------------------------------------------------------------------
   4) 秀美课堂 · 知识问答：白底 + 晨雾飞鸟极淡底纹
   -------------------------------------------------------------------------- */
#classroom-knowledge {
  position: relative;
  overflow: hidden;
  background: linear-gradient(180deg, var(--nat-mist) 0%, #ffffff 100%);
}

#classroom-knowledge::before {
  content: "";
  position: absolute;
  inset: 0;
  background: url(../images/bg/nature-birds.jpg) right center / cover no-repeat;
  opacity: 0.14;
  pointer-events: none;
}

#classroom-knowledge > .container {
  position: relative;
  z-index: 1;
}