@import url('https://fonts.googleapis.com/css2?family=Lato:ital,wght@0,100;0,300;0,400;0,700;0,900;1,100;1,300;1,400;1,700;1,900&display=swap');

:root {
    --mainColor: crimson;
    --black: #000000;
    --white: #FFFFFF;
    --whiteSmoke: #C4C3CA;
    --shadow: 0px 4px 8px 0 rgba(21, 21, 21, .2);
}

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

::before, ::after { box-sizing: border-box; }

body {
    font-family: 'Lato', sans-serif;
    font-size: 16px;
    letter-spacing: 1px;
    font-weight: normal;
    background-image: url('/static/index/img/login-bg.jpg');
    background-size: cover; /* 确保覆盖整个页面 */
    background-position: center;
    background-repeat: no-repeat;
    min-height: 100vh; /* 最小高度为视口高度，内容超出时自动扩展 */
    margin: 0;
    padding: 0;
}

a { text-decoration: none; }
ul { list-style: none; }
.container { max-width: 1080px; margin: auto; }
.row { display: flex; flex-wrap: wrap; }
.justify-content-between { justify-content: space-between; }
.align-items-center { align-items: center; }
.full-screen { 
    min-height: 100vh; 
    padding: 0; /* 移除顶部 80px 的 padding */
}
.text-center { text-align: center; }

/*NAV*/

nav {
    width: 100%;
    background-color: transparent; /* 保持导航栏透明 */
    padding: 15px;
}

nav .logo { color: var(--white); font-size: 32px; font-weight: 600; text-transform: capitalize; }
    nav .logo span { color: var(--mainColor); }
nav .container { padding: 0 25px; }
nav .menu-btn i { color: var(--white); font-size: 28px; cursor: pointer; display: none; }
nav ul { display: flex; flex-wrap: wrap; }
    nav ul li { margin: 0 5px; }
        nav ul li a { 
            color: var(--white); 
            font-size: 16px; 
            font-weight: 600; 
            padding: 8px 15px;
            border-radius: 5px;
            transition: all .3s ease; 
        }
            nav ul li a.active, nav ul li a:hover { color: var(--mainColor); background: var(--white); }

/*MAIN*/

.left, .right { flex: 0 0 50%; max-width: 50%; padding: 20px; }
    .left .line { width: 15%; height: 2px; background-color: var(--mainColor); display: inline-block; }
    .left h2 { margin-top: 25px; font-size: 50px; color: var(--white); line-height: 55px; }
        .left h2 span { color: var(--mainColor); font-size: 52px; }
    .left p { color: var(--whiteSmoke); font-size: 16px; margin-top: 20px; margin-bottom: 10px; }

.btn {
    height: 44px;
    padding: 0px 30px;
    background-color: var(--mainColor);
    border-radius: 4px;
    font-size: 13px;
    font-weight: 600;
    text-transform: uppercase;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    color: var(--white);
    letter-spacing: 1px;
    border: none;
    margin-top: 15px;
    box-shadow: 0px 8px 24px 0 rgba(228, 10, 57, .2);
    transition: all .2s linear;
}

.btn:hover { background-color: var(--white); color: var(--mainColor); box-shadow: 0 8px 24px 0 rgba(138, 140, 146, .2); }

.social-media { margin-top: 60px; }
.social-media a {
    color: var(--white);
    margin-right: 22px;
    font-size: 22px;
    text-decoration: none;
    transition: all .2s linear;
}

.social-media a:hover { color: var(--mainColor); }

.form { width: 100%; display: flex; justify-content: center; }
.right h4 { font-weight: 600; color: var(--white); }
.right h6 { color: var(--white); margin-bottom: 20px; } 
.right h6 span { padding: 0 20px; text-transform: uppercase; font-weight: 700; font-size: 16px; }

input[type="checkbox"] { display: none; }
.checkbox:checked + label, .checkbox:not(:checked) + label { 
    position: relative;
    display: block;
    text-align: center;
    width: 60px;
    height: 16px;
    border-radius: 8px;
    background-color: var(--mainColor);
    padding: 0;
    margin: 10px auto;
    cursor: pointer;
}

.checkbox:checked + label::before, .checkbox:not(:checked) + label::before {
    position: absolute;
    display: block;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    color: var(--mainColor);
    background-color: var(--white);
    font-family: 'Material Icons';
    content: '\f1e2';
    z-index: 20;
    top: -10px;
    left: -10px;
    line-height: 36px;
    text-align: center;
    font-size: 24px;
    transition: all .5s ease;
}

.checkbox:checked + label::before { transform: translateX(44px) rotate(-270deg); }

.link { color: var(--whiteSmoke); margin-top: 20px; display: block; }
.link:hover { color: var(--mainColor); }

.card-3d-wrap {
    position: relative;
    width: 400px;
    max-width: 100%;
    height: 400px;
    margin-top: 60px;
    transform-style: preserve-3d;
    perspective: 800px;
}

.card-3d-wrapper {
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    transform-style: preserve-3d;
    transition: all .6s ease-out;
}

.checkbox:checked ~ .card-3d-wrap .card-3d-wrapper { transform: rotateY(180deg); }

.card-front, .card-back { 
    width: 100%; 
    height: 100%;
    background-color: rgba(27, 27, 27, 0.9); /* 半透明黑色，透明度为 0.6（60% 不透明） */
    background-image: url('/assets/css/background.png');
    background-position: bottom center;
    background-repeat: no-repeat;
    background-size: 300%;
    position: absolute;
    border-radius: 6px;
    left: 0;
    top: 0;
    transform-style: preserve-3d;
}
.card-back { transform: rotateY(180deg); }

.center-wrap {
    position: absolute;
    width: 100%;
    padding: 0 35px;
    top: 50%;
    left: 0;
    transform: translate3d(0, -50%, 35px) perspective(100px);
    display: block;
    z-index: 20;
}

.heading { margin-bottom: 20px; font-size: 24px; text-transform: uppercase; }
.form-group { position: relative; display: block; margin-bottom: 10px; }
.form-group input::placeholder { color: var(--whiteSmoke); opacity: .7; transition: all .2s linear; }
.form-group input:focus::placeholder { opacity: 0; transition: all .2s linear; }

.form-style {
    padding: 13px 20px;
    padding-left: 55px;
    height: 48px;
    width: 100%;
    font-weight: 500;
    border-radius: 4px;
    font-size: 14px;
    line-height: 22px;
    letter-spacing: 0.5px;
    outline: none;
    color: var(--whiteSmoke);
    background-color: #242323;
    border: none;
    box-shadow: var(--shadow);
}

.form-style:focus, .form-style:active { border: none; outline: none; box-shadow: var(--shadow); }

.input-icon {
    position: absolute;
    top: 12px;
    left: 18px;
    height: 48px;
    font-size: 24px;
    text-align: left;
    color: var(--mainColor);
    transition: all .2s linear;
}

/* 弹出层及语言选择样式 */
.van-overlay {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 1;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7); /* 遮罩层 */
    display: none;
}
.van-popup {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: #fff;
    z-index: 2030;
    display: none;
}
.languages {
    display: flex;
    justify-content: space-around;
    align-items: center;
    height: 100%;
}
.languages .item {
    width: 20%;
    text-align: center;
    position: relative;
}
.languages .item img {
    width: 2.1rem;
    height: 2.1rem;
    margin-bottom: 0.9rem;
}
.languages .item p {
    font-size: 12px;
}
.languages .active:after {
    position: absolute;
    width: 0.6rem;
    height: 0.08rem;
    background-color: #5cacf6;
    content: "";
    left: 50%;
    transform: translateX(-50%);
    bottom: -0.2rem;
    border-radius: 0.04rem;
}

/* 导航栏中语言图标区域 */
.nav-left {
    display: flex;
    align-items: center;
}
.i18n img {
    width: 2.1rem;
    height: 2.1rem;
    cursor: pointer;
}

/* 去除底部的黑色背景 */
footer {
    background-color: transparent; /* 使底部背景透明 */
}

/*MEDIA QUERIES*/

@media (max-width: 992px) {
    nav .menu-btn i { display: block; }
    nav .container { padding: 0; }
    nav ul { 
        position: fixed;
        top: 85px;
        left: -100%;
        background-color: #1B1B1B;
        height: 320px;
        width: 100%;
        display: block;
        text-align: center;
        transition: all .3s ease;
    }

    #click:checked ~ ul { left: 0; }
    nav ul li { margin: 20px 0; }
    nav ul li a { display: block; font-size: 20px; }
    nav ul li a.active, nav ul li a:hover { background: none; color: var(--mainColor); }

    .left h2 { font-size: 40px; }
    .left h2 span { font-size: 42px; }
    .left p { font-size: 14px; }
    .card-3d-wrap { width: 350px; }
}

@media (max-width: 768px) {
    .left, .right { flex: 0 0 100%; max-width: 100%; }
    .left { display: grid; place-items: center; order: 2; }
    .right { order: 1; }
    .left h2 { text-align: center; }
    .languages .item { width: 25%; }
    .van-popup { height: auto; padding: 1rem; }
}

@media (max-width: 400px) {
    .left h2 { font-size: 28px; }
    .left h2 span { font-size: 30px; }
    .card-3d-wrap { width: 300px; }
}