@charset "utf-8";
@import url('https://fonts.googleapis.com/css?family=Lato:300,400,700,900');

/* ===================== 基础 ===================== */
* { box-sizing: border-box; }

body {
    font-family: "Lato", sans-serif;
    line-height: 1.6;
    font-size: 15px;
    margin: 0 auto;
    color: #191919;
    /* 桌面背景图 —— 1920x1080 */
    background: #0a0a12 url("../images/desktop-bg.png") no-repeat center top;
    background-size: cover;
    min-height: 100vh;
}

a {
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s;
}
a:hover, a:focus { text-decoration: none; }

img { max-width: 100%; }

.container { width: 100%; }
.h-100 { min-height: 100vh; }

/* ===================== 国家按钮组（桌面端） ===================== */
.countryCustom {
    position: fixed;
    bottom: 5%;
    left: 65%;          /* 往右调：数字越大越靠右 */
    right: auto;
    margin: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.country {
    display: flex;
    justify-content: center;
    gap: 50px;
}

.country a {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 0;
}

.country a .flag-icon {
    display: block;
    width: 90px;
    height: 90px;
}

.country a img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    transition: filter 0.3s ease;
    filter: drop-shadow(2px 4px 6px rgba(0,0,0,.35));
}

.country a p {
    font-size: 15px;
    color: #dfdfdf;
    font-weight: bold;
    margin: 6px 0 0;
    text-shadow: 0 1px 3px rgba(0,0,0,.6);
    transition: color 0.3s, text-shadow 0.3s, transform 0.3s;
}

/* ===================== 桌面端 icon 特效 ===================== */
@media (min-width: 901px) {
    .country a {
        position: relative;
    }

    .country a .flag-icon {
        position: relative;
        border-radius: 50%;
        transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
    }

    .country a .flag-icon::before {
        content: '';
        position: absolute;
        inset: -6px;
        border-radius: 50%;
        border: 2px solid transparent;
        transition: border-color 0.3s, box-shadow 0.3s;
        pointer-events: none;
    }

    .country a .flag-icon::after {
        content: '';
        position: absolute;
        inset: 0;
        border-radius: 50%;
        background: linear-gradient(135deg, rgba(255,255,255,0.45) 0%, transparent 55%);
        opacity: 0;
        transition: opacity 0.3s;
        pointer-events: none;
    }

    .country a img {
        transition: filter 0.35s ease, transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
    }

    /* Hover */
    .country a:hover .flag-icon {
        transform: translateY(-10px) scale(1.12);
    }

    .country a:hover .flag-icon::before {
        border-color: rgba(0, 210, 255, 0.75);
        box-shadow:
            0 0 18px rgba(0, 190, 255, 0.65),
            0 0 36px rgba(0, 130, 255, 0.35);
    }

    .country a:hover .flag-icon::after {
        opacity: 1;
    }

    .country a:hover img {
        filter:
            drop-shadow(0 0 10px rgba(0, 200, 255, 0.85))
            drop-shadow(2px 4px 6px rgba(0,0,0,.35))
            brightness(1.12);
    }

    .country a:hover p {
        color: #7dd3ff;
        text-shadow: 0 0 12px rgba(0, 180, 255, 0.9);
        transform: translateY(-2px);
    }

    /* Click */
    .country a.is-clicked {
        pointer-events: none;
    }

    .country a.is-clicked .flag-icon {
        animation: flagClickPop 0.48s ease forwards;
    }

    .country a.is-clicked .flag-icon::before {
        animation: flagClickRing 0.55s ease-out forwards;
    }

    .country a.is-clicked p {
        color: #fff;
        text-shadow: 0 0 16px rgba(0, 220, 255, 1);
    }
}

@keyframes flagClickPop {
    0%   { transform: translateY(-10px) scale(1.12); }
    35%  { transform: translateY(2px) scale(0.88); }
    65%  { transform: translateY(-4px) scale(1.06); }
    100% { transform: translateY(0) scale(1); }
}

@keyframes flagClickRing {
    0% {
        transform: scale(1);
        opacity: 1;
        border-color: rgba(0, 220, 255, 0.9);
        box-shadow: 0 0 0 0 rgba(0, 200, 255, 0.6);
    }
    100% {
        transform: scale(1.55);
        opacity: 0;
        border-color: rgba(0, 200, 255, 0);
        box-shadow: 0 0 0 18px rgba(0, 200, 255, 0);
    }
}

/* 标语图（桌面显示，手机隐藏） */
.slogan {
    max-width: 500px;
    margin-bottom: 24px;
}

/* ===================== 可选元素 ===================== */
.btn-logo { display: none; }
.btn-logo img {
    height: 30px;
    margin: 0 auto;
    display: block;
}

.btn-content {
    position: fixed;
    bottom: 5%;
    left: 5%;
    display: none;
}
.btn-content img { width: 70%; }

/* ===================== 入场动画延迟 ===================== */
.fadeInLeft.first  { animation-delay: 0.5s; animation-iteration-count: 1; }
.fadeInLeft.second { animation-delay: 1s;   animation-iteration-count: 1; }
.fadeInLeft.third  { animation-delay: 1.5s; animation-iteration-count: 1; }
.fadeInLeft.four   { animation-delay: 2s;   animation-iteration-count: 1; }
.fadeInLeft.five   { animation-delay: 2.5s; animation-iteration-count: 1; }

/* 浮动效果 */
.floating {
    animation-name: floating;
    animation-duration: 3s;
    animation-iteration-count: infinite;
    animation-timing-function: ease-in-out;
}
@keyframes floating {
    from { transform: translate(0, 0); }
    50%  { transform: translate(0, 15px); }
    to   { transform: translate(0, 0); }
}

/* ===================== 手机端 ===================== */
@media (max-width: 900px) {
    body {
        /* 手机背景图 —— 1080x1920。注意扩展名要和你的文件一致！ */
        background: #0a0a12 url("../images/mobile-bg.png") no-repeat center top;
        background-size: cover;
    }

    /* 强制拉回居中，覆盖桌面端的 left:38% */
    .countryCustom {
        left: 0;
        right: 0;
        margin: 0 auto;
        max-width: 100%;
        bottom: 5%;
    }

    .country {
        flex-wrap: wrap;
        gap: 24px;
    }

    .country a .flag-icon {
        width: 60px;
        height: 60px;
    }

    .country a img {
        width: 100%;
        height: 100%;
    }

    .country a p {
        font-size: 14px;
        margin: 4px 0 0;
    }

    .slogan { display: none; }
}

/* ===================== 背景音乐开关 ===================== */
#bgm-toggle {
    position: fixed;
    top: 16px;
    right: 16px;
    z-index: 9999;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: rgba(0,0,0,.45);
    color: #fff;
    font-size: 22px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    user-select: none;
    -webkit-backdrop-filter: blur(4px);
    backdrop-filter: blur(4px);
}