html, body {
    margin: 0;
    padding: 0;
    height: 100%;
    background: #f5f5f5;
    font-family: "MiSans", "PingFang SC", "Microsoft YaHei", sans-serif;
}
#composeApp { height: 100%; }
.loading {
    position: fixed; inset: 0; display: flex; align-items: center; justify-content: center;
    background: #f5f5f5; z-index: 9999; transition: opacity .3s;
}
.loading.hidden { opacity: 0; pointer-events: none; }
.loading-card {
    background: #fff; border-radius: 16px; padding: 24px 40px;
    box-shadow: 0 8px 24px rgba(0,0,0,.08); color: #666;
}