/* ========================================
   C 端内页公共顶部栏（深蓝渐变）
   所有内页共用：飞行手册 / 视频平台 / 赛事 / 钉钉课堂 / 百科 / 智能教练
   以后改顶部样式只改这一个文件
   ======================================== */

.header {
    background: linear-gradient(135deg, #1e3c72 0%, #2a5298 100%);
    color: #fff;
    padding: 16px 20px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header h1 {
    font-size: 20px;
    font-weight: 600;
    margin: 0;
}

.header-plane {
    color: #5dade2;
    margin-right: 6px;
    font-size: 22px;
    transform: rotate(-15deg);
    display: inline-block;
    animation: planeBob 3s ease-in-out infinite;
}

@keyframes planeBob {
    0%, 100% { transform: rotate(-15deg) translateY(0); }
    50% { transform: rotate(-10deg) translateY(-3px); }
}

.btn-back {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 4px 8px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 6px;
    color: rgba(255, 255, 255, 0.9);
    text-decoration: none;
    font-size: 11px;
    font-weight: 500;
    transition: all 0.3s;
    white-space: nowrap;
}

.btn-back:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateX(-2px);
}

.btn-back i {
    font-size: 10px;
}

.header-title {
    text-align: center;
    flex: 1;
    margin: 0 10px;
}

.header-right {
    min-width: 60px;
    text-align: right;
}

.header-subtitle {
    font-size: 12px;
    opacity: 0.85;
    font-weight: 400;
    color: rgba(255, 255, 255, 0.9);
}

@media (max-width: 768px) {
    .header { padding: 12px 14px; }
    .header h1 { font-size: 16px; }
    .header-plane { font-size: 18px; margin-right: 4px; }
    .btn-back { font-size: 10px; padding: 3px 6px; gap: 2px; }
    .btn-back i { font-size: 9px; }
    .header-subtitle { font-size: 11px; }
    .header-title { margin: 0 6px; }
}