/* =========================
   TOP / HERO SECTION
   ========================= */

.top {
    position: relative;
    width: 100%;
    min-height: 100vh;
    background-color: #000;
    overflow: hidden;

    /* 核心：用 Flex 而不是 translateY */
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;

    text-align: center;
    box-sizing: border-box;
}

/* 背景图 */
.top-back-img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.5;
    z-index: 0;
    filter: blur(10px);
    animation: backImg 10s linear infinite,
    topBackImgOpacity 13s linear infinite;
}

/* 文本容器 */
.top-text-box {
    position: relative;
    z-index: 100;
    color: #fff;
    width: 100%;
    padding: 30px 20px;
    box-sizing: border-box;
}

/* LOGO + 标题 */
.top-logo-title {
    font-weight: bold;
    letter-spacing: 2px;
    font-size: 70px;
    color: #ffffff;
    text-shadow: 0px 5px 10px rgba(118,118,118,.5);
}

.top-logo {
    display: inline-block;
    width: 30px;
    height: 20px;
    margin-bottom: -20px;
    opacity: 0;
    /*filter: grayscale(100%);*/
    /*animation: topLogoAnimation 5s linear infinite;*/
}

/* 标语 */
.top-text-in {
    margin-top: 16px;
    font-size: 30px;
    letter-spacing: 6px;
    font-weight: bold;
    color:#F9BB00;
    text-shadow: 0 0 10px rgba(118,118,118,.5);
}

.top-text-in div {
    font-size: inherit;
}

/* 底部说明文字 */
.top-bottom-f {
    position: absolute;
    bottom: 20px;
    left: 0;
    width: 100%;
    z-index: 100;
    padding: 0 20px;
    box-sizing: border-box;
    font-size: 16px;
    letter-spacing: 2px;
    color: #ffffff;
    text-shadow: 0 0 10px rgba(0,0,0,.5);
}

.top-bottom-f-z {
    margin: 0 10px;
    font-weight: bold;
    font-size: 17px;
}

/* 向上图标 */
.top-up-icon {
    width: 20px;
    height: 20px;
    margin-top: 10px;
    animation: topUpIconAnimation 1s linear infinite;
}

/* =========================
   动画
   ========================= */

/*@keyframes topLogoAnimation {*/
/*    0% { filter: grayscale(100%); }*/
/*    50% { filter: grayscale(0%); }*/
/*    100% { filter: grayscale(100%); }*/
/*}*/

@keyframes backImg {
    0%   { filter: blur(0px); }
    70%  { filter: blur(5px); }
    100% { filter: blur(0px); }
}

@keyframes topBackImgOpacity {
    0%   { opacity: .5; }
    50%  { opacity: 1; }
    100% { opacity: .5; }
}

@keyframes topUpIconAnimation {
    0%   { transform: translateY(0); opacity: 1; }
    50%  { transform: translateY(-10px); opacity: .8; }
    100% { transform: translateY(0); opacity: 1; }
}

@media (min-width: 769px) {
    .top-text-box{
        transform: translateY(-190px);
    }
}

/* =========================
   Mobile (<= 768px)
   ========================= */

@media (max-width: 768px) {

    .top {
        justify-content: flex-start; /* 手机上视觉稍偏上更稳 */
        padding-top: 120px;
        min-height: 100svh; /* 新 viewport 单位，防地址栏抖动 */
        /*border-radius: 0 0 30px 30px;*/
        box-shadow: 0 0 10px rgba(0,0,0,.5);
    }

    .top-logo-title {
        font-size: 30px;
        letter-spacing: 1px;
    }

    .top-logo {
        width: 30px;
        height: 15px;
        margin-bottom: -10px;
    }

    .top-text-in {
        font-size: 18px;
        letter-spacing: 2px;
    }

    .top-text-in div {
        font-size: 14px;
    }

    .top-bottom-f {
        font-size: 12px;
        opacity: .8;
    }

    .top-bottom-f-z {
        font-size: 14px;
    }
}