/* 基礎樣式重設 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

body {
    background-color: #000000;
    color: #ffffff;
    line-height: 1.5;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color 0.2s ease;
}

/* 頂部主導覽列 */
.navbar {
    display: flex;
    align-items: center; /* 改為置中對齊，手機上畫面更平衡 */
    padding: 20px;       /* 減少手機端兩側間距 */
    background-color: #000000;
    max-width: 800px;
    margin: 0 auto;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    font-weight: bold;
    font-size: 20px;
    letter-spacing: -0.5px;
    animation: breath 3s infinite;
}

/* 讓 Logo 圖片在手機上等比例縮小不爆開 */
.logo img {
    max-height: 40px;
    width: auto;
}

.nav-auth {
    display: flex;
    align-items: center;
    gap: 12px; /* 稍微縮小間距適應手機 */
    font-size: 14px;
}

.btn-signup {
    background-color: #ffffff;
    color: #000000;
    padding: 6px 14px; /* 稍微縮小襯距 */
    border-radius: 20px;
    font-weight: 500;
    transition: opacity 0.2s ease;
}

.btn-signup:hover {
    opacity: 0.9;
}

.btn-login {
    color: #ffffff;
}

/* 主視覺區域 (Hero Section) */
.main {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
    padding: 20px 20px 40px 20px; /* 調整手機內縮 padding */
}

.main h1 {
    font-size: 36px; /* 手機端字體調小，避免單字斷行太難看 */
    font-weight: 700;
    letter-spacing: -1px;
    line-height: 1.2;
    margin-bottom: 16px;
}

.main p {
    font-size: 24px; /* 手機端字體調小 */
    color: #999999;
    margin-bottom: 24px;
    font-weight: 400;
}

/* 分類區塊 (Categories) */
.categories-section {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px 40px 20px; /* 大幅縮減手機版左右超大的 80px 邊距 */
    display: block; /* 移除 grid，讓內容正常開展 */
}

/* 卡片網格：核心 RWD 改善 */
.grid-container {
    display: grid;
    grid-template-columns: repeat(4, 1fr); /* 電腦版維持 4 欄 */
    gap: 20px;
}

/* 每一組商品的包裹外殼 */
.card-item {
    display: flex;
    flex-direction: column;
    gap: 12px;
    cursor: pointer;
}

.card-item:hover .card {
    border-color: #333333;
    transform: translateY(-2px);
}

/* 純黑底的卡片格子本身 */
.card {
    background-color: #161616;
    border-radius: 12px;
    border: 1px solid #222222;
    aspect-ratio: 16 / 12; /* 🚀 關鍵：改用比例控制，移除絕對寬高(326x244) */
    transition: transform 0.2s, border-color 0.2s;
    overflow: hidden; 
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%; /* 🚀 關鍵：寬度撐滿網格欄位 */
}

.card img {
    width: 100%;
    height: 100%;
    object-fit: cover; 
    transition: transform 0.3s ease;
}

.card-item:hover .card img {
    transform: scale(1.03);
}

/* 下半部資訊的彈性外殼 */
.card-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;            
    padding: 0 4px;                 
}

.card-item .price {
    font-size: 15px; /* 稍微縮小字體更精緻 */
    font-weight: 500;
    line-height: 1.4;
    color: #ffffff;
    text-align: left;
    white-space: nowrap;      /* 防止商品名稱跟價格擠壓 */
    overflow: hidden;
    text-overflow: ellipsis;  /* 商品名過長時自動變 ... */
    max-width: 60%;          /* 留空間給右邊按鈕 */
}

.card-item .currency {
    font-size: 13px;
    color: #cccccc; 
}

/* 右側「購買」按鈕的樣式 */
.btn-buy {
    background-color: #ffffff;      
    color: #000000;                 
    padding: 6px 16px; /* 縮小按鈕，防止在小手機上與左邊文字打架 */
    border-radius: 20px;            
    font-size: 13px;
    font-weight: 600;
    text-align: center;
    text-decoration: none;
    transition: opacity 0.2s ease;
    flex-shrink: 0; /* 防止按鈕被壓扁 */
}

.btn-buy:hover {
    opacity: 0.9;
}

.btn-buy.btn-download {
    background-color: #00ffa3 !important;
    color: #000000 !important;
}

/* 🚀 響應式斷點 (RWD 覆寫設定) */
@media (max-width: 1200px) {
    .grid-container { grid-template-columns: repeat(3, 1fr); } /* 螢幕稍小變 3 欄 */
}

@media (max-width: 768px) {
    .navbar { padding: 15px 20px; }
    .grid-container { grid-template-columns: repeat(2, 1fr); } /* 平板與大手機變 2 欄 */
    
    /* 修正：不隱藏 nav-auth，而是隱藏 welcome 歡迎詞以留出空間給按鈕 */
    .nav-auth .user-welcome { display: none !important; } 
}

@media (max-width: 480px) {
    .grid-container { grid-template-columns: repeat(1, 1fr); } /* 窄版手機直接變直式 1 欄，最好閱讀 */
    .main h1 { font-size: 36px; }
    .card { aspect-ratio: 16 / 10; } /* 手機單欄時，縮減一點黃金比例高度 */
}

/* 動畫部分保持原樣 */
@-webkit-keyframes breath{30%{-webkit-transform: scale(1);transform: scale(1);opacity: 1;}70%{-webkit-transform: scale(1.05);transform: scale(1.05);opacity: .1;}}
@keyframes breath{30%{-webkit-transform: scale(1);transform: scale(1);opacity: 1;}70%{-webkit-transform: scale(1.05);transform: scale(1.05);opacity: .1;}}