/* --- 基础变量 (与主页保持统一色调) --- */
:root {
    --primary-color: #0056A3; 
    --bg-light: #f8f9fa;
    --text-dark: #333333;
    --white: #ffffff;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Helvetica Neue", sans-serif;
    background-color: var(--bg-light);
    color: var(--text-dark);
}

/* --- 顶部导航 --- */
.gallery-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 50px;
    background-color: var(--white);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 15px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    z-index: 100;
}

.back-btn {
    text-decoration: none;
    color: var(--primary-color);
    font-size: 1rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    width: 60px;
}

.back-btn i {
    margin-right: 5px;
}

.gallery-title {
    font-size: 1.1rem;
    font-weight: bold;
    color: var(--text-dark);
}

.header-placeholder {
    width: 60px; /* 与返回按钮等宽，确保标题绝对居中 */
}

/* --- 相册网格区 --- */
.gallery-container {
    padding: 70px 10px 40px; /* 顶部留出导航栏空间 */
}

.gallery-tips {
    text-align: center;
    font-size: 0.8rem;
    color: #888;
    margin-bottom: 15px;
}

.photo-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr); /* 手机端两列显示 */
    gap: 8px; /* 图片间距 */
}

.photo-item {
    width: 100%;
    aspect-ratio: 4 / 3; /* 之前修改的4:3比例 */
    border-radius: 6px;
    overflow: hidden;
    background-color: #eaeaea;
    box-shadow: 0 2px 6px rgba(0,0,0,0.08);
    
    /* 【新增】：让图片初始状态隐藏、稍微缩小且偏下 */
    opacity: 0;
    transform: translateY(30px) scale(0.95);
    /* 加入平滑过渡属性 */
    transition: opacity 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94), 
                transform 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

/* 【新增】：当 JavaScript 侦测到图片进入屏幕时，加上这个类让图片浮现 */
.photo-item.show {
    opacity: 1;
    transform: translateY(0) scale(1);
}

.photo-item:active {
    opacity: 0.8; /* 点击反馈 */
}

.photo-item img {
    width: 100%;
    height: 100%;
    /* 【核心修复】将原来的 cover 改为 contain。
       contain 会保证无论原图是横屏还是竖屏，都能按原比例 100% 完整显示在框内，绝不放大裁剪 */
    object-fit: contain; 
    
    /* 【视觉优化】因为图片完整显示后，上下或左右必定会留出空白。
       这里加一个深色底色，让它看起来像一个高级的暗色相框。
       (如果你喜欢浅色边框，可以把 #1a1a1a 改成 #f4f4f4 或 #ffffff) */
    background-color: #1a1a1a; 
    
    display: block;
}

/* --- 大图预览层 (Lightbox) --- */
.lightbox {
    display: none; /* 默认隐藏 */
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.95);
    z-index: 2000;
    justify-content: center;
    align-items: center;
}

.lightbox-wrapper {
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

#lightbox-img {
    max-width: 100%;
    max-height: 90vh; /* 限制最高高度 */
    object-fit: contain; /* 完整显示原比例大图 */
    border-radius: 4px;
}

.lightbox-close {
    position: absolute;
    top: 20px;
    right: 20px;
    color: var(--white);
    font-size: 2rem;
    z-index: 2001;
    cursor: pointer;
    padding: 10px;
}
/* =========================================
   相册华丽入场动画特效 (Curtain Reveal)
   ========================================= */

/* 1. 深蓝色拉幕遮罩层 */
.page-transition-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: linear-gradient(135deg, var(--primary-color) 0%, #002b52 100%);
    z-index: 9999; /* 确保层级最高，遮住一切 */
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    color: var(--gold-color);
    /* 遮罩停留 0.6 秒后，开始向上滑动隐藏 */
    animation: slideUpCurtain 0.8s cubic-bezier(0.77, 0, 0.175, 1) 0.6s forwards;
}

/* 2. 中间跳动的相机 Logo */
.transition-logo {
    text-align: center;
    /* Logo 弹出的动画 */
    animation: pulseLogo 0.6s cubic-bezier(0.175, 0.885, 0.32, 1.275) forwards;
}

.transition-logo i {
    font-size: 3.5rem;
    margin-bottom: 15px;
}

.transition-logo p {
    font-size: 1.1rem;
    letter-spacing: 2px;
    color: var(--white);
}

/* 3. 配合幕布拉开，整个相册网页有一个“从下往上浮现”的视差跟进效果 */
body {
    animation: contentParallaxFade 1s cubic-bezier(0.77, 0, 0.175, 1) 0.4s both;
}

/* --- 动画关键帧定义 --- */
@keyframes slideUpCurtain {
    0% { transform: translateY(0); }
    100% { transform: translateY(-100%); visibility: hidden; }
}

@keyframes pulseLogo {
    0% { transform: scale(0.5); opacity: 0; }
    100% { transform: scale(1); opacity: 1; }
}

@keyframes contentParallaxFade {
    0% { transform: translateY(60px); opacity: 0; }
    100% { transform: translateY(0); opacity: 1; }
}