/* =========================================
   1. 基礎設定與字體
   ========================================= */
body {
    font-family: 'Noto Sans TC', sans-serif;
    background: linear-gradient(135deg, #1a0b2e 0%, #2d1b4e 50%, #1a0b2e 100%);
    color: #f8fafc;
    overflow-x: hidden;
    min-height: 100vh;
}

/* =========================================
   2. 玻璃擬態效果 (Glassmorphism)
   ========================================= */
.glass {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.glass-pink {
    background: rgba(255, 183, 197, 0.1);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 183, 197, 0.2);
}

/* =========================================
   3. 文字與按鈕特效
   ========================================= */
.text-glow {
    text-shadow: 0 0 10px rgba(255, 183, 197, 0.5), 0 0 20px rgba(255, 183, 197, 0.3);
}

.btn-glow:hover {
    box-shadow: 0 0 15px rgba(255, 105, 180, 0.6), 0 0 30px rgba(255, 105, 180, 0.4);
}

/* =========================================
   4. 櫻花飄落動畫
   ========================================= */
.sakura-petal {
    position: fixed;
    top: -10vh;
    width: 15px;
    height: 15px;
    background: radial-gradient(circle, #ffb7c5 0%, #ff91a4 50%, rgba(255,183,197,0) 70%);
    border-radius: 150% 0 150% 0;
    pointer-events: none;
    z-index: 0;
    opacity: 0.8;
    animation: fall linear infinite;
}

@keyframes fall {
    0% { 
        transform: translateY(-10vh) rotate(0deg); 
        opacity: 1; 
    }
    100% { 
        transform: translateY(110vh) rotate(360deg); 
        opacity: 0; 
    }
}

/* =========================================
   5. 自定義滾動條
   ========================================= */
::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: #1a0b2e;
}
::-webkit-scrollbar-thumb {
    background: #ff69b4;
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: #ff1493;
}

/* =========================================
   6. 可展開卡片樣式 (核心修改：浮動展開)
   ========================================= */
.expandable-card {
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative; /* 作為絕對定位子元素的參考點 */
    overflow: visible;  /* 允許內容溢出卡片邊界 */
    z-index: 1;         /* 基礎層級 */
}

.expandable-card:hover {
    transform: translateY(-2px);
    border-color: rgba(255, 105, 180, 0.4);
}

/* 展開箭頭動畫 */
.expand-arrow {
    transition: transform 0.3s ease;
    color: #ffb7c5;
}

.expandable-card.expanded .expand-arrow {
    transform: rotate(180deg);
}

/* 展開內容：使用絕對定位，完全脫離文檔流，不擠佔空間 */
.expandable-card .expand-content {
    position: absolute;
    top: 100%; /* 緊貼卡片底部 */
    left: 50%; /* 水平居中 */
    transform: translateX(-50%); /* 修正居中偏移 */
    width: calc(100% + 2rem); /* 比卡片稍寬，視覺更平衡 */
    max-height: 0;
    overflow: hidden;
    opacity: 0;
    transition: max-height 0.4s ease, opacity 0.4s ease, padding 0.4s ease;
    padding: 0 1.5rem;
    
    /* 視覺樣式：深色背景 + 邊框 + 陰影 */
    background: linear-gradient(180deg, rgba(45, 27, 78, 0.98) 0%, rgba(26, 11, 46, 0.95) 100%);
    border: 1px solid rgba(255, 183, 197, 0.3);
    border-top: none;
    border-radius: 0 0 1.5rem 1.5rem;
    z-index: 50; /* 確保顯示在其他卡片上方 */
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.6), 0 0 40px rgba(255, 105, 180, 0.1);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

/* 展開狀態 */
.expandable-card.expanded .expand-content {
    max-height: 2000px; /* 足夠大的值以容納內容 */
    opacity: 1;
    padding: 1.5rem;
    margin-top: 0.5rem; /* 與卡片保持一點距離 */
}

/* 展開時提升卡片層級，防止被旁邊卡片遮擋 */
.expandable-card.expanded {
    z-index: 100;
}

/* 手機版適配 */
@media (max-width: 768px) {
    .expandable-card:hover {
        transform: none; /* 手機上取消 hover 位移 */
    }
    
    .expandable-card .expand-content {
        width: calc(100% + 1rem);
        padding: 0 1rem;
    }
    
    .expandable-card.expanded .expand-content {
        padding: 1rem;
    }
}

/* =========================================
   7. 內容區塊樣式 (代碼塊、提示框等)
   ========================================= */
.code-block {
    background: rgba(0, 0, 0, 0.4);
    border-left: 3px solid #ff69b4;
    padding: 0.75rem 1rem;
    border-radius: 0.5rem;
    font-family: 'Courier New', monospace;
    color: #ffb7c5;
    font-size: 0.9rem;
    overflow-x: auto;
    margin: 0.5rem 0;
}

.tip-box {
    background: rgba(255, 183, 197, 0.1);
    border: 1px solid rgba(255, 183, 197, 0.3);
    border-radius: 0.75rem;
    padding: 0.75rem 1rem;
    font-size: 0.875rem;
    margin-top: 0.5rem;
}

.warning-box {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    border-radius: 0.75rem;
    padding: 0.75rem 1rem;
    font-size: 0.875rem;
    color: #fca5a5;
    margin-top: 0.5rem;
}

/* =========================================
   8. 漢堡選單樣式
   ========================================= */
.mobile-menu {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.mobile-menu.open {
    max-height: 500px;
}

.hamburger-line {
    display: block;
    width: 24px;
    height: 2px;
    background: #ffb7c5;
    transition: all 0.3s ease;
    margin: 5px 0;
}

.hamburger.active .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active .hamburger-line:nth-child(2) {
    opacity: 0;
}

.hamburger.active .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}