/* 基础重置 */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Inter', sans-serif;
    color: #404242;
    line-height: 2;
    overflow-x: hidden;
    background-color: #50ADBA;
}

/* 原站的复杂渐变与图案背景 */
.background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    /* 使用 CSS 渐变模拟原版的 SVG 几何背景效果 */
    background: linear-gradient(45deg, #50ADBA 0%, #55A7C2 100%);
    /* 原版带有一层网格图案，此处用纯净渐变替代，更加现代化 */
}

/* 主容器 */
.wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 6rem 1.5rem;
    max-width: 32rem;
    margin: 0 auto;
    z-index: 1;
}

/* 卡片通用样式 */
.card {
    width: 100%;
    text-align: center;
    margin-bottom: 2.5rem;
}

.card.solid {
    background-color: #FFFFFF;
    border-radius: 0.875rem;
    padding: 3rem;
    box-shadow: 0 4px 15px rgba(0,0,0,0.05);
}

.card.transparent {
    background: transparent;
    padding: 0;
}

/* 图片处理 */
.logo-frame {
    width: 9rem;
    height: 9rem;
    margin: 0 auto 1.5rem;
    border-radius: 50%;
    border: 8px solid #FFFFFF;
    overflow: hidden;
}

.logo-frame img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* 修改顶部大图，使其等比自动缩放，绝不截断 */
.hero-image {
    display: block;
    width: calc(100% + 6rem);  /* 抵消卡片的 padding，使图片撑满顶部宽度 */
    margin-left: -3rem;
    margin-top: -3rem;
    margin-bottom: 1.5rem;
    height: auto;              /* 取消固定高度，改为自动缩放 */
    object-fit: contain;       /* 确保图片内容100%完整包含在内 */
    border-top-left-radius: 0.875rem;
    border-top-right-radius: 0.875rem;
}

/* 手机端适配也需要同步修改 */
@media (max-width: 480px) {
    .card.solid { 
        padding: 2rem; 
    }
    .hero-image {
        width: calc(100% + 4rem); /* 抵消手机端的 padding */
        margin-left: -2rem;
        margin-top: -2rem;
        height: auto;             /* 同样取消手机端的固定高度 */
    }
}

/* 排版与字体 */
.site-title {
    color: #FFFFFF;
    font-family: 'Lexend Deca', sans-serif;
    font-size: 3.75em;
    font-weight: 400;
    line-height: 1.125;
    margin-bottom: 1rem;
}

.site-subtitle {
    color: rgba(255, 255, 255, 0.678);
    font-size: 1em;
}

.section-title {
    color: #404242;
    font-family: 'Lexend Deca', sans-serif;
    font-size: 2em;
    font-weight: 400;
    line-height: 1.25;
    margin-bottom: 1rem;
}

.section-text {
    color: rgba(64, 66, 66, 0.702);
    font-size: 1em;
    margin-bottom: 1.5rem;
}

.footer-title {
    color: #FFFFFF;
    font-family: 'Lexend Deca', sans-serif;
    font-size: 2em;
    font-weight: 400;
    margin-bottom: 1.5rem;
}

/* 分隔线 */
.divider {
    border: none;
    border-top: 2px dashed rgba(64, 66, 66, 0.122);
    margin: 2rem 0;
}

.spacer {
    border: none;
    width: 3px;
    height: 9rem;
    background-color: #FFFFFF;
    margin: 0 auto 2.5rem;
}

/* 按钮样式 */
.button-group {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    text-decoration: none;
    font-size: 1em;
    border-radius: 0.5rem;
    background-color: #7AC4B7;
    background-image: linear-gradient(45deg, #7AB7C4 0%, rgba(122,196,183,0.008) 100%);
    color: #FFFFFF;
    transition: transform 0.25s ease;
}

.btn:hover {
    transform: scale(1.0425);
}

.btn .icon {
    margin-right: 8px;
    font-size: 1.2em;
}

/* 社交图标 */
.social-icons {
    display: flex;
    justify-content: center;
    gap: 1.25rem;
    flex-wrap: wrap;
}

.icon-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 4rem;
    height: 4rem;
    border-radius: 50%;
    border: 3px solid #FFFFFF;
    color: #FFFFFF;
    font-size: 1.5rem;
    text-decoration: none;
    transition: transform 0.25s ease;
}

.icon-link:hover {
    transform: scale(1.1125);
}

/* 底部版权 */
.credits {
    margin-top: 3rem;
    font-size: 12px;
    color: rgba(255, 255, 255, 0.5);
}

/* === 动画属性 === */
.fade-up {
    opacity: 0;
    transform: translateY(2rem);
    transition: opacity 1s ease, transform 1s ease;
}

.fade-in {
    opacity: 0;
    transition: opacity 1s ease;
}

.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* 修改并补充 .icon-link 内 SVG 的样式，使其和原版一模一样 */
.icon-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 4rem;
    height: 4rem;
    border-radius: 50%;
    border: 3px solid #FFFFFF;
    transition: transform 0.25s ease;
    /* 去除 font-size，因为现在使用的是 SVG 而非文字 */
}

.icon-link svg {
    width: 60%;
    height: 60%;
    fill: #FFFFFF; /* 图标颜色设为纯白 */
    pointer-events: none;
}