* {
    margin:0;
    padding:0;
    box-sizing:border-box;
}

body {
    font-family:-apple-system,BlinkMacSystemFont,"SF Pro Text","PingFang SC","Helvetica Neue",sans-serif;
    height:100vh;
    overflow:hidden;
}

/* ===== 背景（苹果柔和渐变） ===== */
.bg {
    position:fixed;
    width:100%;
    height:100%;

    background: url("../images/bg.jpg") no-repeat center center;
    background-size: cover;
    z-index:-1;
}

/* ===== 居中 ===== */
.wrapper {
    display:flex;
    justify-content:center;
    align-items:center;
    height:100%;
}

/* ===== 苹果卡片（重点） ===== */
.card {
    width:300px;
    padding:80px;

    background: rgba(255,255,255,0.6);
    backdrop-filter: blur(20px);

    border-radius:22px;

    text-align:center;

    box-shadow: 
        0 20px 50px rgba(0,0,0,0.08),
        inset 0 1px rgba(255,255,255,0.6);

    animation: fadeIn 0.5s ease;
}

/* LOGO */
.logo {
    width:150px;
    margin-bottom:18px;
}

/* ===== 加载圈（iOS风） ===== */
.loader {
    width:40px;
    height:40px;
    border:3px solid rgba(0,0,0,0.08);
    border-top:3px solid #007aff;
    border-radius:50%;

    margin:0 auto 18px;

    animation: spin 1s linear infinite;
}

@keyframes spin {
    100% { transform: rotate(360deg); }
}

/* 标题 */
h2 {
    font-size:18px;
    font-weight:600;
    color:#1d1d1f;
    margin-bottom:6px;
}

/* 描述 */
p {
    font-size:13px;
    color:#6e6e73;
}

/* ===== 按钮（iOS蓝） ===== */
.btn {
    display:inline-block;
    margin-top:22px;

    padding:10px 22px;

    background:#f87171;
    color:#fff;

    border-radius:20px;

    font-size:14px;
    font-weight:500;

    text-decoration:none;

    transition:0.2s;
}

.btn:hover {
    background:#0066d6;
}

/* 隐藏 */
.hidden {
    display:none;
}

/* 动画 */
@keyframes fadeIn {
    from {
        opacity:0;
        transform:translateY(15px);
    }
    to {
        opacity:1;
        transform:translateY(0);
    }
}