:root { --dark-blue: #1E3650; --light-blue: #2980B9; }
body { font-family: "Microsoft YaHei", sans-serif; }

/* 导航栏 */
.navbar { background: var(--dark-blue); }
.navbar-brand, .nav-link { color: #fff !important; }
.nav-link:hover, .nav-link.active { color: #7FC4E8 !important; }

/* 首屏 Banner */
.hero { background: linear-gradient(135deg, #1E3650, #2980B9); color: #fff; padding: 100px 0 80px; text-align: center; }
.hero h1 { font-size: 2.8rem; font-weight: bold; }
.hero p { font-size: 1.2rem; opacity: 0.9; margin-top: 20px; }
.hero .btn-download { background: #fff; color: var(--dark-blue); font-weight: bold; padding: 12px 40px; border-radius: 30px; margin-top: 30px; text-decoration: none; display: inline-block; }
.hero .btn-download:hover { background: #EAF4FB; }

/* 页面标题横幅 */
.page-header { background: linear-gradient(135deg, #1E3650, #2980B9); color: #fff; padding: 60px 0; text-align: center; }
.page-header h1 { font-weight: bold; }
.page-header p { opacity: 0.9; margin-bottom: 0; }

/* 通用标题 */
.section-title { text-align: center; font-weight: bold; color: var(--dark-blue); margin-bottom: 50px; }
.text-dark-blue { color: var(--dark-blue) !important; }

/* 首页功能卡片 */
.feature-card { border: none; box-shadow: 0 4px 16px rgba(0,0,0,0.06); border-radius: 12px; padding: 30px 20px; transition: transform 0.2s; height: 100%; }
.feature-card:hover { transform: translateY(-5px); }
.feature-icon { font-size: 2.5rem; color: var(--light-blue); margin-bottom: 15px; }
.feature-card h5 { font-weight: bold; color: var(--dark-blue); margin-bottom: 12px; }
.feature-card p { color: #666; font-size: 0.95rem; }

/* 功能介绍页 */
.feature-block { background: #fff; border-radius: 12px; box-shadow: 0 4px 16px rgba(0,0,0,0.06); padding: 30px; height: 100%; }
.feature-block .icon-box { width: 60px; height: 60px; border-radius: 12px; background: #EAF4FB; color: var(--light-blue); display: flex; align-items: center; justify-content: center; font-size: 1.8rem; margin-bottom: 15px; }
.feature-block h4 { color: var(--dark-blue); font-weight: bold; font-size: 1.15rem; margin-bottom: 10px; }
.feature-block p { color: #64748B; font-size: 0.95rem; margin: 0; }

/* 截图区块 */
.screenshot-section { background: #F8FAFC; padding: 80px 0; }
.screenshot-box { border-radius: 12px; box-shadow: 0 8px 24px rgba(0,0,0,0.1); overflow: hidden; background: #fff; padding: 10px; }
.screenshot-box img { width: 100%; border-radius: 8px; }

/* 技术特点 */
.tech-section { padding: 80px 0; }
.tech-item { display: flex; align-items: flex-start; margin-bottom: 25px; }
.tech-item i { font-size: 1.5rem; color: var(--light-blue); margin-right: 15px; margin-top: 3px; }
.tech-item h6 { font-weight: bold; color: var(--dark-blue); margin-bottom: 5px; }
.tech-item p { color: #666; font-size: 0.9rem; margin: 0; }

/* 更新日志 */
.log-item { border-left: 4px solid var(--light-blue); padding-left: 20px; margin-bottom: 30px; }
.log-item h5 { color: var(--dark-blue); font-weight: bold; margin-bottom: 5px; }
.log-item .date { color: #94A3B8; font-size: 0.85rem; margin-bottom: 10px; }
.log-item ul { color: #475569; padding-left: 20px; }
.log-item ul li { margin-bottom: 4px; }

/* 使用教程 */
.tutorial-item { margin-bottom: 40px; }
.tutorial-item h4 { color: var(--dark-blue); font-weight: bold; margin-bottom: 12px; }
.tutorial-item p { color: #475569; line-height: 1.8; white-space: pre-wrap; }

/* 徽章 */
.badge-dev { background: #E2E8F0; color: #64748B; font-size: 0.7rem; padding: 3px 8px; border-radius: 10px; vertical-align: middle; }

/* 页脚 */
footer { background: var(--dark-blue); color: #fff; padding: 40px 0; text-align: center; }
footer a { color: #7FC4E8; text-decoration: none; }
/* ===== 教程页 PDF 显示 ===== */
.pdf-wrapper {
    width: 100%;
    height: 1200px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 16px rgba(0,0,0,0.08);
    background: #fff;
}
.pdf-wrapper iframe {
    width: 100%;
    height: 100%;
    border: none;
}
@media (max-width: 768px) {
    .pdf-wrapper { height: 600px; }
}
/* ===== 教程页版本 Tab 按钮 ===== */
.nav-pills .nav-link {
    color: #475569 !important;
    background: #F1F5F9;
    border: 1px solid #E2E8F0;
    margin: 0 4px;
    padding: 8px 20px;
    border-radius: 30px;
    font-weight: 500;
    transition: all 0.2s;
}

.nav-pills .nav-link:hover {
    color: #1E3650 !important;
    background: #E2E8F0;
    border-color: #CBD5E1;
}

.nav-pills .nav-link.active {
    color: #fff !important;
    background: #2980B9 !important;
    border-color: #2980B9;
    box-shadow: 0 4px 12px rgba(41,128,185,0.3);
}

.nav-pills .nav-link i {
    margin-right: 4px;
}