/* Banner样式 */
.banner {
    position: relative;
    width: 100%;
    height: 600px;
    background: 
        linear-gradient(135deg, rgba(232, 237, 243, 0.3), rgba(240, 244, 249, 0.3)), 
        url("../images/IMUT_day.jpg") no-repeat center center;
    background-size: cover;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    overflow: hidden;
}

/* 隐藏原背景图片 */
.banner-img {
    display: none;
}

.banner-text {
    z-index: 2;
    position: relative; /* 确保层级高于背景图 */
}

.banner-text h1 {
    font-size: 42px;
    font-weight: 700;
    color: #1d2129;
    margin-bottom: 16px;
    text-shadow: 0 1px 3px rgba(0,0,0,0.1); /* 轻微阴影增强可读性 */
}

.banner-text p {
    font-size: 18px;
    color: #4e5969;
    margin-bottom: 32px;
}

/* 按钮组改为链接组样式 */
.banner-btn-group {
    display: flex;
    margin-left: 40px;
    gap: 20px;
}

/* 核心：链接样式 */
.banner-link {
    padding: 10px 24px;
    border-radius: 4px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    text-decoration: none; /* 去除链接下划线 */
    display: inline-block; /* 保证padding生效 */
    transition: all 0.3s ease;
}

.banner-link.primary {
    background-color: #165dff;
    color: #fff !important; /* 强制白色，避免继承链接颜色 */
    text-align: center;
}

.banner-link.primary:hover {
    background-color: #0d47a1;
    text-decoration: none; /* hover时也无下划线 */
}

.banner-link.secondary {
    background-color: #fff;
    color: #165dff !important;
    border: 1px solid #165dff;
}
body.night-mode .feature-section {
  background-color: #1d2129;
}

body.night-mode .feature-section .section-title h2 {
  color: #fff;
}

body.night-mode .feature-card {
  background-color: #2c3036;
  color: #e5e6eb;
}

body.night-mode .feature-card h3 {
  color: #4d88ff;
}

body.night-mode .feature-card p {
  color: #c0c4cc;
}

body.night-mode .feature-card:hover {
  box-shadow: 0 4px 12px rgba(77, 136, 255, 0.15);
}
.banner-link.secondary:hover {
    background-color: #f0f5ff;
    text-decoration: none;
}
/* 板块通用标题 - 提升层级，适配业务范围背景图 */
.section-title {
    text-align: center;
    margin-bottom: 0;
    padding-top: 20px;
    position: relative;
    z-index: 10; /* 关键：让标题层级高于背景图 */
}
.section-title h2 {
    font-size: 28px;
    color: black;
    margin-bottom: 8px;
    display: inline-block;
    border-bottom: 2px solid #165DFF;
    padding-bottom: 6px;
    /*background: rgba(255,255,255,0.8);  白天标题加浅背景，更醒目 */
    padding: 0 20px 6px;
    border-radius: 4px 4px 0 0;
}
/* 夜晚板块标题 */
body.night-mode .section-title h2 {
    font-size: 28px;
    color: #fff;
    margin-bottom: 8px;
    display: inline-block;
    border-bottom: 2px solid #fff;
    padding-bottom: 6px;
    /*background: rgba(29,33,41,0.8);  夜间标题加深色背景，更醒目 */
}
/* 板块1：产研学用融合模式 */
.feature-section {
    padding: 60px 0;
    background-color: #fff;
}

.feature-section .section-title {
    text-align: center;
    margin-bottom: 40px;
}

.feature-section .section-title h2 {
    font-size: 28px;
    font-weight: 700;
    color: #1d2129;
}

.feature-container {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px; /* 原24px → 缩小间距，减少空白 */
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.feature-card {
    background-color: #f7f8fa;
    padding: 28px 20px; /* 原24px → 适度放大但减少冗余内边距 */
    border-radius: 8px;
    /* 移除scale缩放（避免额外空白），保留hover阴影 */
    transition: box-shadow 0.3s ease;
}

/* 隐藏原卡片图片 */
.feature-card .feature-img {
    display: none;
}

.feature-card h3 {
    font-size: 22px; /* 原20px → 放大标题 */
    font-weight: 600;
    color: #165dff;
    margin-bottom: 10px; /* 原12px → 缩小间距，减少空白 */
    line-height: 1.2; /* 紧凑行高 */
}

.feature-card p {
    font-size: 15px; /* 原14px → 放大正文 */
    color: #4e5969;
    line-height: 1.6;
    margin: 0; /* 移除默认margin，减少空白 */
}

/* hover效果（仅阴影，无缩放，避免空白） */
.feature-card:hover {
    box-shadow: 0 4px 12px rgba(22, 93, 255, 0.1);
}
/* 板块2：业务范围*/
.business-section {
    margin-bottom: 80px;
    /* background-color: #abb3c7; */
    color: #fff;
    border-radius: 8px;
    padding: 0;
    min-height: 300px;
    position: relative;
    overflow: hidden;
    display: flex;
    justify-content: center;
}

/* 业务范围背景图 */
.business-section .bg-img {
    width: 100%;
    max-width: 1200px;
    height: 100%;
    object-fit: cover;
    object-position: center;
    position: absolute;
    border-radius: 8px;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
    opacity: 0.25; /* 深色图保持稍高透明度，保留科技感 */
    transition: opacity 0.5s ease-in-out;
}

/* 夜间模式背景图透明度 */
body.night-mode .business-section .bg-img {
    opacity: 0.6;
}

.business-section .container {
    width: 100%;
    max-width: 1200px;
    min-height: 500px;
    position: relative;
    z-index: 5;
    padding: 20px; 
}

.business-content-title {
    font-size: 24px;
    margin-bottom: 20px;
    color: #000000; /* 纯黑，保证最高对比度 */
    text-shadow: 0 2px 6px rgba(255, 255, 255, 0.9); /* 白色柔光，让文字从背景里跳出来 */
    font-weight: 700;
}

.business-content-desc {
    font-size: 18px;
    max-width: 800px;
    line-height: 1.8;
    color: #1d2129; /* 深灰，比纯黑柔和一点 */
    text-shadow: 0 1px 4px rgba(255, 255, 255, 0.8);
}



.business-card-group {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 20px 20px 0 20px;
    z-index: 6;
}

.business-card {
    background-color: #e8edf3;
    color: #1d2129;
    height: 100px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    position: relative;
    clip-path: polygon(
        10% 0,
        90% 0,
        100% 15%,
        100% 85%,
        90% 100%,
        10% 100%,
        0 85%, 
        0 15%
    );
    border-radius: 12px;
    transition: all 0.3s ease;
    padding: 10px 10px 0 10px;
    overflow: hidden;
}

/* 白天 hover 颜色（更浅、更干净） */
.business-card:hover {
    background-color: #f0f4fa;
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0,0,0,0.08);
}

/* 夜间模式卡片 */
body.night-mode .business-card {
    background-color: #2c3036;
    color: #e5e6eb;
}

/* 夜间模式 hover */
body.night-mode .business-card:hover {
    background-color: #3b3f46;
    box-shadow: 0 8px 16px rgba(0,0,0,0.25);
}

.business-card h3 {
    font-size: 18px;
    margin-bottom: 8px;
    font-weight: 600;
    /* 确保文字居中不被切角遮挡 */
    position: relative;
    z-index: 1;
}

.business-card a {
    font-size: 14px;
    color: #165DFF;
}

.business-card a:hover {
    text-decoration: underline;
}
/* 板块3：团体活动（照片墙） */
.activity-section {
    margin-bottom: 80px;
}
.photo-wall {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 24px;
}
.photo-item {
    border-radius: 8px;
    overflow: hidden;
    height: 200px;
    position: relative;
}
.photo-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s;
}
.photo-item:hover img {
    transform: scale(1.05);
}
.photo-desc {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    background: linear-gradient(transparent, rgba(0,0,0,0.6));
    color: #fff; /* 照片描述固定白色 */
    padding: 12px;
    font-size: 14px;
    text-align: center;
}
/* 板块4：三大列表+在线咨询 */
.list-section {
    margin-bottom: 80px;
}
.list-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    position: relative;
}
/* 板块4：三大列表+在线咨询 */
.list-section {
    margin-bottom: 80px;
}
.list-container {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    position: relative;
}
.list-card {
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 2px 12px rgba(22,93,255,0.08);
    padding: 24px;
    transition: background-color 0.3s, box-shadow 0.3s;
}
/* 行业观察列表*/
.list-card--weak {
    background: #FAFBFC;
    box-shadow: 0 1px 4px rgba(0,0,0,0.05);
    border: 1px solid #F2F3F5;
}

.list-card--weak h3 {
    color: #333; 
}
.list-card--weak .list-item a {
    color: #6E7681;
}

.list-card--weak:hover {
    box-shadow: 0 2px 8px rgba(22,93,255,0.06);
    background: #fff;
}
/* 夜间模式  */
body.night-mode .list-card--weak {
    background: #24272B; 
    box-shadow: 0 1px 4px rgba(0,0,0,0.2);
    border-color: #373B41;
}
body.night-mode .list-card--weak h3 {
    color: #C0C4CC; 
}
body.night-mode .list-card--weak .list-item a {
    color: #86909C;
}
body.night-mode .list-card--weak:hover {
    background: #2C3036;
    box-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

body.night-mode .list-card {
    background-color: #2C3036;
    box-shadow: 0 2px 12px rgba(0,0,0,0.3);
}
.list-card h3 {
    font-size: 18px;
    color: #000; 
    margin-bottom: 16px;
    display: flex;
    align-items: center;
}
body.night-mode .list-card h3 {
    color: #fff; 
}
.list-item {
    margin-bottom: 12px;
    padding-bottom: 12px;
    border-bottom: 1px solid #F2F3F5;
}
body.night-mode .list-item {
    border-bottom-color: #373B41;
}
.list-item:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}
.list-item a {
    font-size: 14px;
    color: #4E5969; /* 白天列表链接：深灰 */
    transition: color 0.3s;
}
body.night-mode .list-item a {
    color: #E5E6EB; /* 夜间列表链接：浅白 */
}
.list-item a:hover {
    color: #165DFF; /* 悬停品牌蓝不变 */
}
/* 固定在线咨询入口 */
.consult-fixed {
    position: fixed;
    right: 30px;
    bottom: 30px;
    background-color: #165DFF;
    color: #fff;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 16px rgba(22,93,255,0.2);
    cursor: pointer;
    z-index: 998;
    transition: all 0.3s;
}
.consult-fixed:hover {
    transform: scale(1.1);
    box-shadow: 0 6px 20px rgba(22,93,255,0.3);
}
.consult-fixed span {
    font-size: 24px;
}

@media (max-width: 767px) {
  /* ========== 移动端 Banner 优化 ========== */
  .banner {
    height: clamp(500px, 90vh, 650px);
    padding: 0 20px;
    background-position: center top;
    background-size: cover;
  }

  .banner-text h1 {
    font-size: clamp(26px, 7vw, 36px);
    line-height: 1.3;
    margin-bottom: 16px;
  }

  .banner-text p {
    font-size: clamp(15px, 4vw, 20px);
    line-height: 1.5;
    margin-bottom: 30px;
  }

  .banner-btn-group {
    flex-direction: column;
    gap: 14px;
    width: 100%;
    max-width: 320px;
    margin: 0 auto;
  }

  .banner-link {
    width: 100%;
    padding: 14px 0;
    font-size: 16px;
  }

  .feature-container {
    grid-template-columns: 1fr;
    gap: 16px;
    padding: 0 16px;
  }

  .feature-card {
    padding: 22px 18px;
  }

  .feature-card h3 {
    font-size: 20px;
  }

  .feature-card p {
    font-size: 15px;
  }

.business-section {
    margin-bottom: 40px;
  }

  .business-section .container {
    min-height: auto;
    padding: 15px;
    position: relative;
    padding-bottom: 180px !important; /* 给底部卡片留出足够空间 */
  }

  .business-content {
    padding: 20px 10px;
    min-height: auto;
    display: block;
  }

  .business-content-title {
    font-size: 20px;
    line-height: 1.4;
    margin-bottom: 12px;
    word-break: break-all;
  }

  .business-content-desc {
    font-size: 15px;
    line-height: 1.6;
    word-break: break-all;
  }

  /* 👇 核心：卡片固定在板块底部，不飘、不遮挡 */
  .business-card-group {
    position: absolute;
    left: 0;
    bottom: 15px;
    width: 100%;
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
    padding: 0 12px;
    z-index: 6;
  }

  .business-card {
    height: 85px;
    padding: 8px;
    clip-path: polygon(8% 0, 92% 0, 100% 12%, 100% 88%, 92% 100%, 8% 100%, 0 88%, 0 12%);
  }

  .business-card h3 {
    font-size: 14px;
    line-height: 1.3;
    text-align: center;
    padding: 0 4px;
  }

  .activity-section {
    margin-bottom: 50px;
  }

  .photo-wall {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
    padding: 0 16px;
  }

  .photo-item {
    height: 160px;
  }

  .photo-desc {
    font-size: 13px;
    padding: 10px 6px;
  }

  .list-section {
    margin-bottom: 60px;
  }

  .list-container {
    grid-template-columns: 1fr;
    gap: 16px;
    padding: 0 16px;
  }

  .list-card {
    padding: 20px;
  }

  .list-card h3 {
    font-size: 17px;
  }

  .list-item a {
    font-size: 15px;
  }

  .consult-fixed {
    width: 55px;
    height: 55px;
    right: 20px;
    bottom: 20px;
  }

  .section-title h2 {
    font-size: 24px;
  }

  .container {
    padding: 0 10px;
  }
}