/**
 * 文章導航 - 完整樣式表(修正版)
 * Version: 5.2.6
 * 修正: 文章導航標籤樣式 parity 與資產版本統一
 */

* {
    box-sizing: border-box;
}

/* ========================================
   CSS 變數定義
======================================== */
:root {
/* 圖片尺寸(由 PHP 動態設定) */
--post-nav-side-img-width: 200px;
--post-nav-side-img-height: 150px;
--post-nav-top-img-ratio: 16 / 9;
--post-nav-img-fit: cover;
--post-nav-title-lines: 3;
--nav-border-radius: 12px;
--nav-shadow: 0 4px 12px rgba(0,0,0,0.1);
--nav-hover-effect: zoom;

/* 顏色系統 - 亮色模式(預設) */
--nav-primary: #2563eb;
--nav-primary-hover: #1d4ed8;
--nav-text: #111827;
--nav-text-secondary: #4b5563;
--nav-text-light: #6b7280;
--nav-bg: #ffffff;
--nav-bg-hover: #f9fafb;
--nav-border: #e5e7eb;
--nav-overlay: rgba(0, 0, 0, 0.75);

/* 間距 */
--nav-spacing-xs: 4px;
--nav-spacing-sm: 8px;
--nav-spacing-md: 16px;
--nav-spacing-lg: 24px;
--nav-spacing-xl: 32px;

/* 動畫 */
--nav-transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
--nav-transition-fast: all 0.2s ease;
}

/* 深色模式變數 */
body.dark-mode {
--nav-text: #f9fafb;
--nav-text-secondary: #d1d5db;
--nav-text-light: #9ca3af;
--nav-bg: #1f2937;
--nav-bg-hover: #111827;
--nav-border: #374151;
--nav-overlay: rgba(0, 0, 0, 0.85);

/* --- ▼▼▼ 以下為新增的通用深色模式樣式 ▼▼▼ --- */

/* 設定頁面背景和文字顏色 */
background-color: #181a1b; /* 深色背景 */
color: #e8e6e3; /* 淺色文字 */

/* 確保您的文章內容區域也應用這些顏色 */
/* 注意：您可能需要根據您的佈景主題修改下面的選擇器，例如 .entry-content 或 #main */
.site-content, 
.entry-content,
.post-content {
 background-color: transparent; /* 繼承 body 的背景色 */
 color: inherit; /* 繼承 body 的文字顏色 */
}

/* 通用連結顏色 */
a {
color: #8ab4f8;
}

a:hover {
color: #a3c5fb;
}

/* 標題顏色 */
h1, h2, h3, h4, h5, h6 {
color: #f1f1f1;
}

/* --- ▲▲▲ 以上為新增的通用深色模式樣式 ▲▲▲ --- */
}
/* ========================================
   深色模式切換按鈕
======================================== */
.dark-mode-toggle {
position: fixed;
bottom: calc(24px + var(--hd-bottom-fixed-safe-offset, 0px));
right: 24px;
width: 56px;
height: 56px;
background: var(--nav-primary);
border: none;
border-radius: 50%;
cursor: pointer;
box-shadow: 0 4px 12px rgba(0,0,0,0.15);
z-index: 1000;
display: flex;
align-items: center;
justify-content: center;
transition: var(--nav-transition);
}

.dark-mode-toggle:hover {
transform: scale(1.1);
box-shadow: 0 6px 20px rgba(0,0,0,0.25);
}

.dark-mode-toggle:active {
transform: scale(0.95);
}

.dark-mode-toggle svg {
width: 24px;
height: 24px;
color: white;
transition: var(--nav-transition);
}

.dark-mode-toggle .icon-sun {
display: none;
}

.dark-mode-toggle .icon-moon {
display: block;
}

body.dark-mode .dark-mode-toggle .icon-sun {
display: block;
}

body.dark-mode .dark-mode-toggle .icon-moon {
display: none;
}

@media (max-width: 768px) {
.dark-mode-toggle {
width: 48px;
height: 48px;
bottom: calc(16px + var(--hd-bottom-fixed-safe-offset, 0px));
right: 16px;
}

.dark-mode-toggle svg {
width: 20px;
height: 20px;
}
}

/* ========================================
   基礎佈局
======================================== */
/**
 * 修正：無論單篇或雙篇，都使用 Flexbox 佈局以確保對齊正確
 */
.post-navigation {
display: flex;
justify-content: space-between; /* 保持 space-between，這對單個元素對齊很關鍵 */
flex-wrap: wrap; /* 增加 wrap 以處理手機端堆疊的情況 */
gap: var(--nav-spacing-lg); /* 將 gap 移到這裡統一管理 */
}

/* 上下篇導覽分隔線：預設隱藏，由後台條件與 RWD 狀態啟用 */
.post-nav-divider {
display: none;
flex: 0 0 100%;
height: 1px;
margin: 0 0 var(--post-nav-divider-spacing, 18px);
background: var(--nav-border);
opacity: .72;
}

.post-navigation.divider-style-solid .post-nav-divider {
opacity: 1;
}

.post-navigation.divider-style-dashed .post-nav-divider {
height: 0;
border-top: 1px dashed var(--nav-border);
background: transparent;
opacity: .9;
}

.post-navigation.divider-style-accent .post-nav-divider {
height: 2px;
max-width: 180px;
margin-right: auto;
margin-left: auto;
background: var(--nav-primary);
border-radius: 999px;
opacity: 1;
}

.post-navigation.divider-position-before-next.has-both-posts .post-nav-divider {
display: block;
}

.post-navigation.divider-position-before-next.has-both-posts .nav-next,
.post-navigation.divider-position-before-next.has-both-posts .nav-simple-next,
.post-navigation.divider-position-before-next.has-both-posts .nav-arrow-next {
order: 4;
}

.post-navigation.divider-position-before-next.has-both-posts .post-nav-divider {
order: 3;
}

/* ========== 新增箭頭導航模式 ========== */
.nav-mode-arrow {
display: flex;
align-items: center;
justify-content: center;
gap: var(--nav-spacing-lg);
padding: var(--nav-spacing-lg) 0;
}

.nav-arrow {
display: flex;
align-items: center;
gap: var(--nav-spacing-sm);
padding: 12px 24px;
background: var(--nav-bg);
border: 2px solid var(--nav-border);
border-radius: 50px;
color: var(--nav-text);
text-decoration: none;
font-weight: 600;
font-size: 14px;
transition: var(--nav-transition);
cursor: pointer;
}

.nav-arrow:hover {
background: var(--nav-primary);
border-color: var(--nav-primary);
color: white;
transform: translateY(-2px);
box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.nav-arrow svg {
width: 20px;
height: 20px;
transition: var(--nav-transition);
}

.nav-arrow:hover svg {
color: white;
}

.nav-arrow-prev:hover svg {
transform: translateX(-3px);
}

.nav-arrow-next:hover svg {
transform: translateX(3px);
}

.nav-arrow-disabled {
width: 48px;
height: 48px;
opacity: 0;
pointer-events: none;
}

/* 中間導航按鈕 */
.nav-center-button {
display: flex;
align-items: center;
justify-content: center;
gap: var(--nav-spacing-sm);
padding: 12px 24px;
background: var(--nav-primary);
border: 2px solid var(--nav-primary);
border-radius: 50px;
color: white;
text-decoration: none;
font-weight: 600;
font-size: 14px;
transition: var(--nav-transition);
cursor: pointer;
}

/* 中間導航按鈕 - 只顯示圖示模式 */
.nav-center-button.icon-only {
padding: 12px;
border-radius: 50%;
width: 48px;
height: 48px;
}

.nav-center-button.icon-only svg {
margin: 0;
}

/* 箭頭模式 - 只顯示圖示 */
.nav-mode-arrow .nav-center-button.icon-only {
width: 48px;
height: 48px;
}

/* 完整模式 - 只顯示圖示 */
.nav-center-full.icon-only {
padding: 12px;
width: 48px;
height: 48px;
border-radius: 50%;
}

.nav-center-full.icon-only svg {
margin: 0;
}

/* 手機版調整 */
@media (max-width: 768px) {
/* 有文字模式在手機版隱藏文字 - 已移除，改為顯示 */
/* .nav-center-button.has-text .nav-center-text,
.nav-center-full.has-text span {
display: none;
} */

/* 有文字模式在手機版變成圓形 */
.nav-center-button.has-text {
padding: 10px;
width: 44px;
height: 44px;
border-radius: 50%;
}

.nav-center-full.has-text {
padding: 10px;
width: 44px;
height: 44px;
border-radius: 50%;
}

/* 只顯示圖示模式 */
.nav-center-button.icon-only {
width: 44px;
height: 44px;
padding: 10px;
}

.nav-center-full.icon-only {
width: 44px;
height: 44px;
padding: 10px;
}
}

@media (max-width: 480px) {
.nav-center-button.icon-only,
.nav-center-full.icon-only,
.nav-center-button.has-text,
.nav-center-full.has-text {
width: 40px;
height: 40px;
padding: 8px;
}
}

.nav-center-button:hover {
background: var(--nav-primary-hover);
border-color: var(--nav-primary-hover);
transform: translateY(-2px) scale(1.05);
box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
}

.nav-center-button svg {
width: 20px;
height: 20px;
color: white;
}

.nav-center-text {
color: white;
}


/* 中間導航按鈕 - 完整模式專用 */
.nav-mode-default.has-center-button {
position: relative;
padding-bottom: 60px; /* 增加底部間距以容納按鈕 */
}

.nav-center-full {
position: absolute;
bottom: 0;
left: 50%;
transform: translateX(-50%);
display: flex;
align-items: center;
gap: var(--nav-spacing-sm);
padding: 10px 20px;
background: var(--nav-primary);
border: 3px solid var(--nav-bg);
border-radius: 50px;
color: white;
text-decoration: none;
font-weight: 600;
font-size: 13px;
box-shadow: 0 4px 12px rgba(0,0,0,0.15);
transition: var(--nav-transition);
z-index: 10;
}

.nav-center-full:hover {
background: var(--nav-primary-hover);
transform: translateX(-50%) translateY(-4px) scale(1.05);
box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
}

.nav-center-full svg {
width: 18px;
height: 18px;
color: white;
}

.nav-center-full span {
color: white;
}

/* 手機版 */
@media (max-width: 768px) {
.nav-center-full {
padding: 8px 16px;
font-size: 12px;
/* 確保在手機版也能正確定位 */
bottom: 10px; 
width: auto;
white-space: nowrap;
}

.nav-center-full svg {
width: 16px;
height: 16px;
}

.nav-center-full span {
display: inline-block; /* 手機版顯示文字 */
margin-left: 4px;
}

/* Mobile Stack Mode Center Button Alignment */
.post-navigation.mobile-stack .nav-center-full {
position: static;
transform: none;
margin: 10px auto !important; /* Force centering */
align-self: center;
order: 2;
display: inline-flex;
width: fit-content; /* Ensure width fits content */
left: auto;
right: auto;
}

.post-navigation.mobile-stack.has-center-button {
padding-bottom: 0;
display: flex;
flex-direction: column;
}

.post-navigation.mobile-stack .nav-previous {
order: 1;
}

.post-navigation.mobile-stack .nav-next {
order: 3;
}
}

/* ========================================
   簡單導航模式 (Simple Mode)
======================================== */
.nav-mode-simple {
display: flex;
align-items: center;
justify-content: space-between;
gap: var(--nav-spacing-md);
padding: var(--nav-spacing-lg) 0;
border-top: 1px solid var(--nav-border);
border-bottom: 1px solid var(--nav-border);
}

.nav-mode-simple .nav-simple-prev,
.nav-mode-simple .nav-simple-next {
flex: 1;
display: flex;
}

.nav-mode-simple .nav-simple-prev {
justify-content: flex-start;
}

.nav-mode-simple .nav-simple-next {
justify-content: flex-end;
}

.nav-mode-simple .nav-simple-link {
display: flex;
align-items: center;
gap: var(--nav-spacing-sm);
padding: 10px 20px;
background: var(--nav-bg);
border: 1px solid var(--nav-border);
border-radius: 50px;
color: var(--nav-text);
text-decoration: none;
font-weight: 500;
font-size: 14px;
transition: var(--nav-transition);
white-space: nowrap;
}

.nav-mode-simple .nav-simple-link:hover {
background: var(--nav-primary);
border-color: var(--nav-primary);
color: white;
transform: translateY(-2px);
box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.nav-mode-simple .nav-simple-link svg {
width: 18px;
height: 18px;
flex-shrink: 0;
transition: var(--nav-transition);
}

.nav-mode-simple .nav-simple-link:hover svg {
color: white;
}

.nav-mode-simple .nav-simple-prev .nav-simple-link:hover svg {
transform: translateX(-3px);
}

.nav-mode-simple .nav-simple-next .nav-simple-link:hover svg {
transform: translateX(3px);
}

.nav-mode-simple .nav-simple-text {
color: inherit;
}

.nav-mode-simple .nav-simple-placeholder {
width: 48px;
height: 48px;
opacity: 0;
}

/* 中間按鈕 - 簡單模式 */
.nav-mode-simple .nav-simple-center {
display: flex;
align-items: center;
justify-content: center;
padding: 12px;
background: var(--nav-primary);
border: 2px solid var(--nav-primary);
border-radius: 50%;
color: white;
text-decoration: none;
transition: var(--nav-transition);
flex-shrink: 0;
margin: 0px auto;
}

.nav-mode-simple .nav-simple-center:hover {
background: var(--nav-primary-hover);
border-color: var(--nav-primary-hover);
transform: translateY(-2px) scale(1.1);
box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
}

.nav-mode-simple .nav-simple-center svg {
width: 20px;
height: 20px;
color: white;
}

/* 形狀變體 */
.nav-mode-simple .nav-simple-center.shape-circle {
border-radius: 50%;
width: 48px;
height: 48px;
padding: 0;
}

.nav-mode-simple .nav-simple-center.shape-oval {
border-radius: 50px;
width: auto;
height: auto;
padding: 10px 24px;
aspect-ratio: auto;
}

.nav-mode-simple .nav-simple-center.shape-square {
border-radius: 4px;
width: 48px;
height: 48px;
padding: 0;
}

.nav-mode-simple .nav-simple-center.shape-rounded {
border-radius: 12px;
width: 48px;
height: 48px;
padding: 0;
}

/* 風格變體 */
.nav-mode-simple .nav-simple-center.style-solid {
background: var(--nav-primary);
border-color: var(--nav-primary);
color: white;
}

.nav-mode-simple .nav-simple-center.style-outline {
background: transparent;
border-color: var(--nav-border);
color: var(--nav-text);
}

.nav-mode-simple .nav-simple-center.style-outline:hover {
border-color: var(--nav-primary);
color: var(--nav-primary);
background: transparent;
}

.nav-mode-simple .nav-simple-center.style-outline svg {
color: inherit;
}

.nav-mode-simple .nav-simple-center.style-flat {
background: transparent;
border-color: transparent;
color: var(--nav-text);
box-shadow: none;
}

.nav-mode-simple .nav-simple-center.style-flat:hover {
background: var(--nav-bg-hover);
color: var(--nav-primary);
transform: translateY(-2px);
box-shadow: none;
}

.nav-mode-simple .nav-simple-center.style-flat svg {
color: inherit;
}

/* 簡單模式 - 極簡風格 (Minimal) */
.simple-style-minimal .nav-simple-link {
background: transparent;
border-color: transparent;
padding: 10px 0; /* 減少左右 padding */
}

.simple-style-minimal .nav-simple-link:hover {
background: transparent;
border-color: transparent;
color: var(--nav-primary);
transform: none; /* 移除位移 */
box-shadow: none;
}

.simple-style-minimal .nav-simple-link:hover svg {
color: var(--nav-primary);
}

/* 簡單模式 - 響應式 */
@media (max-width: 768px) {
.nav-mode-simple {
gap: var(--nav-spacing-sm);
padding: var(--nav-spacing-md) 0;
/* 確保手機版堆疊模式生效 */
flex-wrap: wrap; 
}

/* 手機版堆疊模式 - 簡單模式 */
.post-navigation.mobile-stack.nav-mode-simple {
flex-direction: column;
align-items: stretch;
}

.post-navigation.mobile-stack.nav-mode-simple .nav-simple-prev,
.post-navigation.mobile-stack.nav-mode-simple .nav-simple-next {
justify-content: center; /* 堆疊時置中 */
width: 100%;
}

.post-navigation.mobile-stack.nav-mode-simple .nav-simple-link {
width: 100%;
justify-content: center;
}

/* 手機版並排模式 (雙欄) - 簡單模式 */
.post-navigation.mobile-columns.nav-mode-simple {
flex-direction: row;
flex-wrap: nowrap;
align-items: center;
}

.post-navigation.mobile-columns.nav-mode-simple .nav-simple-prev,
.post-navigation.mobile-columns.nav-mode-simple .nav-simple-next {
flex: 1;
width: auto;
min-width: 0; /* 防止內容撐開 */
}

/* 確保連結內容在小螢幕不換行或適當縮放 */
.post-navigation.mobile-columns.nav-mode-simple .nav-simple-link {
width: 100%;
justify-content: center;
padding: 8px 4px; /* 減少內距以容納更多內容 */
}

/* 調整文字大小以適應並排 */
.post-navigation.mobile-columns.nav-mode-simple .nav-simple-text {
font-size: 12px;
white-space: nowrap;
overflow: hidden;
text-overflow: ellipsis;
max-width: 80px; /* 限制文字寬度 */
display: inline-block;
}

.nav-mode-simple .nav-simple-link {
padding: 8px 16px;
font-size: 13px;
}

.nav-mode-simple .nav-simple-link svg {
width: 16px;
height: 16px;
}

.nav-mode-simple .nav-simple-center {
padding: 10px;
}

.nav-mode-simple .nav-simple-center svg {
width: 18px;
height: 18px;
}

/* Mobile Columns Text Visibility */
.post-navigation.mobile-columns.mobile-columns-text-hidden .nav-label-text,
.post-navigation.mobile-columns.mobile-columns-text-hidden .nav-title,
.post-navigation.mobile-columns.mobile-columns-text-hidden .nav-simple-text,
.post-navigation.mobile-columns.mobile-columns-text-hidden .nav-compact-label,
.post-navigation.mobile-columns.mobile-columns-text-hidden .nav-compact-title {
display: none !important;
}

/* Adjust spacing when text is hidden */
.post-navigation.mobile-columns.mobile-columns-text-hidden .nav-simple-link {
justify-content: center;
padding: 12px;
}
}

/* Desktop Text Visibility */
@media (min-width: 1025px) {
.post-navigation.desktop-text-hidden .nav-label-text,
.post-navigation.desktop-text-hidden .nav-title,
.post-navigation.desktop-text-hidden .nav-simple-text,
.post-navigation.desktop-text-hidden .nav-compact-label,
.post-navigation.desktop-text-hidden .nav-compact-title {
display: none !important;
}

/* Adjust spacing/layout when text is hidden */
.post-navigation.desktop-text-hidden .nav-simple-link {
justify-content: center;
}
}

/* Tablet Text Visibility */
@media (min-width: 769px) and (max-width: 1024px) {
.post-navigation.tablet-text-hidden .nav-label-text,
.post-navigation.tablet-text-hidden .nav-title,
.post-navigation.tablet-text-hidden .nav-simple-text,
.post-navigation.tablet-text-hidden .nav-compact-label,
.post-navigation.tablet-text-hidden .nav-compact-title {
display: none !important;
}

/* Adjust spacing/layout when text is hidden */
.post-navigation.tablet-text-hidden .nav-simple-link {
justify-content: center;
}
}

@media (max-width: 480px) {
.nav-mode-simple {
gap: var(--nav-spacing-xs);
}

.nav-mode-simple .nav-simple-link {
padding: 6px 12px;
font-size: 12px;
}

/* .nav-mode-simple .nav-simple-text {
display: none; 
} */

.nav-mode-simple .nav-simple-link svg {
width: 20px;
height: 20px;
}

.nav-mode-simple .nav-simple-center {
padding: 8px;
}

.nav-mode-simple .nav-simple-center svg {
width: 16px;
height: 16px;
}
}

/* ===================================== */


.post-navigation.loaded {
opacity: 1;
transform: translateY(0);
}


/* ========================================
   精簡導航模式 (Compact Mode)
======================================== */
.nav-mode-compact {
display: flex;
align-items: center;
justify-content: space-between;
gap: var(--nav-spacing-md);
position: relative;
}

.nav-compact {
flex: 1;
max-width: calc(50% - var(--nav-spacing-md));
}

.nav-compact a {
display: block;
padding: var(--nav-spacing-md);
background: var(--nav-bg);
border: 1px solid var(--nav-border);
border-radius: var(--nav-border-radius);
text-decoration: none;
transition: var(--nav-transition);
}

.nav-compact a:hover {
background: var(--nav-bg-hover);
border-color: var(--nav-primary);
transform: translateY(-2px);
box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.nav-compact-label {
display: flex;
align-items: center;
gap: var(--nav-spacing-xs);
font-size: 12px;
color: var(--nav-primary);
font-weight: 600;
text-transform: uppercase;
margin-bottom: var(--nav-spacing-xs);
}

.nav-compact-label svg {
width: 14px;
height: 14px;
}

.nav-compact-title {
font-size: 16px;
font-weight: 600;
color: var(--nav-text);
margin: 0;
line-height: 1.4;
display: -webkit-box;
-webkit-line-clamp: 2;
-webkit-box-orient: vertical;
overflow: hidden;
}

.nav-compact a:hover .nav-compact-title {
color: var(--nav-primary);
}

/* 精簡模式 - 中間按鈕 */
.nav-center-compact {
position: absolute;
left: 50%;
transform: translateX(-50%);
padding: 12px;
border-radius: 50%;
background: var(--nav-primary);
border: 3px solid var(--nav-bg);
box-shadow: 0 4px 12px rgba(0,0,0,0.15);
z-index: 10;
display: flex;
align-items: center;
justify-content: center;
gap: var(--nav-spacing-sm);
text-decoration: none;
transition: var(--nav-transition);
}

.nav-center-compact:hover {
transform: translateX(-50%) scale(1.1);
box-shadow: 0 6px 20px rgba(37, 99, 235, 0.4);
}

.nav-center-compact svg {
width: 20px;
height: 20px;
color: white;
display: block;
}

.nav-center-compact.has-text {
border-radius: 50px;
padding: 10px 20px;
}

.nav-center-compact .nav-center-text {
color: white;
font-weight: 600;
font-size: 13px;
}

/* 精簡模式 - 響應式 */
@media (max-width: 768px) {
.nav-mode-compact {
flex-direction: column;
gap: var(--nav-spacing-lg);
}

.nav-compact {
max-width: 100%;
width: 100%;
}

.nav-center-compact {
position: static;
transform: none;
margin: calc(var(--nav-spacing-md) * -1) auto;
}

.nav-center-compact:hover {
transform: scale(1.1);
}

/* 手機版隱藏文字 - 已移除 */
/* .nav-center-compact.has-text .nav-center-text {
display: none;
} */

.nav-center-compact.has-text {
border-radius: 50%;
padding: 10px;
width: 44px;
height: 44px;
}

.nav-center-compact.icon-only {
width: 44px;
height: 44px;
padding: 10px;
}
}

/**
 * 強制修正文章導航雙欄寬度不均的問題
 */
.post-navigation.has-both-posts {
/* 移除 grid 佈局，改用更穩定的 flexbox 來處理 */
display: flex;
justify-content: space-between;
grid-template-columns: none; /* 關閉 grid 的欄位設定 */
gap: var(--nav-spacing-lg); /* 恢復間距 */
margin: 40px auto;
}

.post-navigation .nav-item {
/* 
 * 使用 flex 屬性進行彈性佈局
 * flex-grow: 1 -> 允許項目擴展
 * flex-shrink: 1 -> 允許項目收縮
 * flex-basis: calc(...) -> 理想的基礎寬度
 */
flex: 1 1 calc( (100% - var(--nav-spacing-lg)) / 2 );

/* 【關鍵備用】確保單個項目不會無限擴展 */
max-width: calc( (100% - var(--nav-spacing-lg)) / 2 );
}

/* 針對只有一個項目的特殊情況 */
.post-navigation .nav-item:only-child {
/* 當只有一個子元素時，取消其 flex-grow 屬性，防止它填滿整個寬度 */
flex-grow: 0;

/* 並且為了讓它能正確靠左或靠右，我們需要重置 justify-content */
}

/* 讓只有單個的「下一篇」按鈕能自動靠右 */
.post-navigation .nav-next:only-child {
margin-left: auto;
}



/* ========================================
   卡片基本樣式
======================================== */
.nav-item {
position: relative;
background: var(--nav-bg);
border-radius: var(--nav-border-radius);
overflow: hidden;
transition: var(--nav-transition);
box-shadow: var(--nav-shadow);
display: flex;
flex-direction: column;
}

.nav-item a {
display: flex;
flex-direction: column;
text-decoration: none;
color: var(--nav-text);
flex: 1;
position: relative;
}

/* ========================================
   風格變化
======================================== */
.post-navigation-default .nav-item {
border: 1px solid var(--nav-border);
}

.post-navigation-default .nav-item:hover {
transform: translateY(-4px);
box-shadow: 0 8px 20px rgba(0,0,0,0.12);
}

body.dark-mode .post-navigation-default .nav-item:hover {
box-shadow: 0 8px 20px rgba(0,0,0,0.4);
}

.post-navigation-card .nav-item {
box-shadow: 0 6px 16px rgba(0,0,0,0.08);
border: none;
}

.post-navigation-card .nav-item:hover {
box-shadow: 0 12px 28px rgba(0,0,0,0.15);
transform: translateY(-6px) scale(1.02);
}

body.dark-mode .post-navigation-card .nav-item:hover {
box-shadow: 0 12px 28px rgba(0,0,0,0.5);
}

.post-navigation-minimal .nav-item {
box-shadow: none;
border: 1px solid var(--nav-border);
background: transparent;
}

.post-navigation-minimal .nav-item:hover {
background: var(--nav-bg-hover);
border-color: var(--nav-primary);
}

.post-navigation-minimal .nav-title {
font-weight: 500;
}

.post-navigation-modern .nav-item {
border: 2px solid transparent;
background: linear-gradient(135deg, #f9fafb 0%, #ffffff 100%);
}

body.dark-mode .post-navigation-modern .nav-item {
background: linear-gradient(135deg, #1f2937 0%, #111827 100%);
}

.post-navigation-modern .nav-item:hover {
border-color: var(--nav-primary);
background: var(--nav-bg);
transform: translateY(-4px);
}

.post-navigation-modern .nav-title {
background: linear-gradient(135deg, var(--nav-primary) 0%, #7c3aed 100%);
-webkit-background-clip: text;
-webkit-text-fill-color: transparent;
background-clip: text;
}

.post-navigation-glass .nav-item {
background: rgba(255, 255, 255, 0.7);
backdrop-filter: blur(10px);
border: 1px solid rgba(255, 255, 255, 0.3);
box-shadow: 0 8px 32px rgba(0,0,0,0.1);
}

body.dark-mode .post-navigation-glass .nav-item {
background: rgba(31, 41, 55, 0.7);
border: 1px solid rgba(255, 255, 255, 0.1);
}

.post-navigation-glass .nav-item:hover {
background: rgba(255, 255, 255, 0.85);
transform: translateY(-4px);
}

body.dark-mode .post-navigation-glass .nav-item:hover {
background: rgba(31, 41, 55, 0.85);
}

.post-navigation-gradient .nav-item {
position: relative;
background: var(--nav-bg);
}

.post-navigation-gradient .nav-item::before {
content: '';
position: absolute;
inset: -2px;
background: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
border-radius: calc(var(--nav-border-radius) + 2px);
opacity: 0;
transition: opacity 0.3s ease;
z-index: -1;
}

.post-navigation-gradient .nav-item:hover::before {
opacity: 1;
}

/* ========================================
   導航標籤樣式
======================================== */
.label-style-header .nav-label {
display: flex;
align-items: center;
gap: var(--nav-spacing-sm);
padding: var(--nav-spacing-md);
padding-bottom: var(--nav-spacing-sm);
font-size: 14px;
font-weight: 600;
color: var(--nav-primary);
text-transform: uppercase;
letter-spacing: 0.05em;
}

.label-style-header .nav-previous .nav-label {
justify-content: flex-start;
}

.label-style-header .nav-next .nav-label {
justify-content: flex-end;
}

.label-style-header .nav-label-icon {
width: 16px;
height: 16px;
flex-shrink: 0;
color: var(--nav-primary);
}

.label-style-header .nav-label-text {
color: var(--nav-primary);
}

.label-style-overlay .nav-label {
position: absolute;
z-index: 10;
background: rgba(0, 0, 0, 0.8);
color: white;
padding: var(--nav-spacing-sm) var(--nav-spacing-md);
border-radius: 6px;
font-size: 13px;
font-weight: 600;
backdrop-filter: blur(8px);
display: flex;
align-items: center;
gap: var(--nav-spacing-xs);
}

.label-style-overlay .nav-label * {
color: white;
}

.label-style-overlay .nav-previous .nav-label {
top: var(--nav-spacing-md);
left: var(--nav-spacing-md);
}

.label-style-overlay .nav-next .nav-label {
top: var(--nav-spacing-md);
right: var(--nav-spacing-md);
}

.label-style-arrow .nav-label {
display: none;
}

.label-style-arrow .nav-arrow-indicator {
display: flex !important;
align-items: center;
justify-content: center;
position: absolute;
top: 50%;
transform: translateY(-50%);
width: 48px;
height: 48px;
background: var(--nav-primary);
color: white;
border-radius: 50%;
opacity: 0;
transition: var(--nav-transition);
z-index: 10;
pointer-events: none;
}

.label-style-arrow .nav-arrow-indicator svg {
color: white;
stroke: white;
}

.label-style-arrow .nav-previous .nav-arrow-indicator {
left: var(--nav-spacing-md);
}

.label-style-arrow .nav-next .nav-arrow-indicator {
right: var(--nav-spacing-md);
}

.label-style-arrow .nav-item:hover .nav-arrow-indicator {
opacity: 1;
}

.nav-arrow-indicator {
display: none;
}

/* ========================================
   響應式佈局系統 - 關鍵修正
======================================== */

/* 主容器 */
.nav-main {
display: flex;
flex: 1;
width: 100%; 
}

/* 桌機版 - 圖片在上方(滿版) */
.layout-desktop-top .nav-main {
flex-direction: column;
}

.layout-desktop-top .nav-thumb {
width: 100%;
position: relative;
flex-shrink: 0;
}

/* 使用 padding-bottom 維持長寬比 */
.layout-desktop-top .nav-thumb::after {
content: '';
display: block;
padding-bottom: calc(100% / (var(--post-nav-top-img-ratio)));
}

.layout-desktop-top .nav-thumb img {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
object-fit: cover;
}

/* 桌機版 - 圖片在側邊 */
.layout-desktop-side .nav-main {
flex-direction: row;
gap: var(--nav-spacing-md);
}

.layout-desktop-side .nav-thumb {
flex-shrink: 0;
width: var(--post-nav-side-img-width);
height: var(--post-nav-side-img-height);
position: relative;
}

.layout-desktop-side .nav-thumb img {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}

.layout-desktop-side .desktop-image-left .nav-main {
flex-direction: row;
}

.layout-desktop-side .desktop-image-right .nav-main {
flex-direction: row-reverse;
}

/* 垂直對齊 */
.valign-center.layout-desktop-side .nav-main {
align-items: center;
}

.valign-top.layout-desktop-side .nav-main {
align-items: flex-start;
}

/* ========================================
   圖片樣式
======================================== */
.nav-thumb {
overflow: hidden;
background: #f3f4f6;
}

body.dark-mode .nav-thumb {
background: #374151;
}

.nav-thumb img {
width: 100%;
height: 100%;
object-fit: var(--post-nav-img-fit);
transition: var(--nav-transition);
display: block;
}

/* Hover 效果 */
.nav-item:hover .nav-thumb img {
transform: scale(1.1);
}

[style*="--nav-hover-effect: none"] .nav-item:hover .nav-thumb img {
transform: none;
}

[style*="--nav-hover-effect: brightness"] .nav-item:hover .nav-thumb img {
transform: none;
filter: brightness(1.1);
}

/* 圖片載入骨架 */
.nav-thumb::before {
content: '';
position: absolute;
inset: 0;
background: linear-gradient(90deg, #f3f4f6 25%, #e5e7eb 50%, #f3f4f6 75%);
background-size: 200% 100%;
animation: skeleton-loading 1.5s infinite;
z-index: 1;
pointer-events: none;
opacity: 1;
transition: opacity 0.3s ease;
}

body.dark-mode .nav-thumb::before {
background: linear-gradient(90deg, #374151 25%, #4b5563 50%, #374151 75%);
}

/* 圖片載入完成後立即停止動畫並隱藏骨架 */
.nav-thumb.image-loaded::before {
animation: none !important;
opacity: 0;
display: none;
}

/* 圖片本身也在 z-index 之上 */
.nav-thumb img {
position: relative;
z-index: 2;
}

@keyframes skeleton-loading {
0% { background-position: 200% 0; }
100% { background-position: -200% 0; }
}

/* ========================================
   內容區樣式
======================================== */
.nav-content {
flex: 1;
display: flex;
flex-direction: column;
gap: var(--nav-spacing-sm);
padding: var(--nav-spacing-md);
min-width: 0;
justify-content: space-between; /* <-- 新增這一行 */
}
/* ========================================
   標題樣式
======================================== */
.nav-title {
font-size: 18px;
font-weight: 700;
line-height: 1.4; /* 關鍵：行高為 1.4 */
color: var(--nav-text);
margin: 0;
display: -webkit-box;
-webkit-line-clamp: var(--post-nav-title-lines);
-webkit-box-orient: vertical;
overflow: hidden;
text-overflow: ellipsis;
transition: color 0.2s ease;
min-height: calc(1.4em * var(--post-nav-title-lines));
}

.nav-item:hover .nav-title {
color: var(--nav-primary);
}

.post-navigation-modern .nav-title {
position: relative;
padding-bottom: 4px;
}

.post-navigation-modern .nav-title::after {
content: '';
position: absolute;
bottom: 0;
left: 0;
width: 0;
height: 2px;
background: var(--nav-primary);
transition: width 0.3s ease;
}

.post-navigation-modern .nav-item:hover .nav-title::after {
width: 100%;
}

.post-navigation-card .nav-item:hover .nav-title {
font-weight: 800;
}

/* ========================================
   Meta 資訊樣式
======================================== */
.nav-meta {
display: flex;
flex-wrap: wrap;
gap: var(--nav-spacing-md);
font-size: 13px;
color: var(--nav-text-secondary);
margin-top: var(--nav-spacing-xs);
}

.nav-meta > * {
display: flex;
align-items: center;
gap: 6px;
color: var(--nav-text-secondary);
}

.nav-meta svg {
width: 14px;
height: 14px;
flex-shrink: 0;
opacity: 0.7;
}

.nav-category {
background: #dbeafe;
color: #1e40af;
padding: 4px 10px;
border-radius: 4px;
font-weight: 500;
}

body.dark-mode .nav-category {
background: rgba(37, 99, 235, 0.2);
color: #93c5fd;
}

.nav-date,
.nav-read-time,
.nav-author {
opacity: 0.8;
}

.nav-item:hover .nav-meta > * {
opacity: 1;
}

/* ========================================
   摘要樣式
======================================== */
.nav-excerpt {
font-size: 14px;
line-height: 1.6;
color: var(--nav-text-secondary);
display: -webkit-box;
-webkit-line-clamp: 2;
-webkit-box-orient: vertical;
overflow: hidden;
text-overflow: ellipsis;
margin-top: auto;
}

.nav-item:hover .nav-excerpt {
color: var(--nav-text);
}

/* ========================================
   載入動畫
======================================== */
.animation-none {
opacity: 1;
transform: none;
}

.animation-fade-up.loaded {
animation: fadeUp 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

@keyframes fadeUp {
from {
opacity: 0;
transform: translateY(30px);
}
to {
opacity: 1;
transform: translateY(0);
}
}

.animation-fade-in.loaded {
animation: fadeIn 0.6s ease forwards;
}

@keyframes fadeIn {
from { opacity: 0; }
to { opacity: 1; }
}

.animation-slide-in .nav-previous {
transform: translateX(-30px);
}

.animation-slide-in .nav-next {
transform: translateX(30px);
}

.animation-slide-in.loaded .nav-item {
animation: slideIn 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

@keyframes slideIn {
to {
opacity: 1;
transform: translateX(0);
}
}

/* ========================================
   響應式斷點 - 平板
======================================== */
@media (max-width: 1024px) and (min-width: 769px) {
.layout-tablet-top .nav-main {
flex-direction: column !important;
}

.layout-tablet-top .nav-thumb {
width: 100% !important;
height: auto !important;
}

.layout-tablet-side .tablet-image-left .nav-main {
flex-direction: row !important;
}

.layout-tablet-side .tablet-image-right .nav-main {
flex-direction: row-reverse !important;
}
}

/* ========================================
   響應式斷點 - 手機(根據後台設定)
======================================== */
@media (max-width: 768px) {
.nav-title {
font-size: 16px;
}

.nav-content {
padding: var(--nav-spacing-md);
}

.nav-meta {
font-size: 12px;
gap: var(--nav-spacing-sm);
}

.nav-excerpt {
font-size: 13px;
}

/* 手機版堆疊模式(由後台設定控制) - 修正 */
.post-navigation.mobile-stack.has-both-posts {
flex-direction: column; /* 1. 將主軸方向改為垂直 */
gap: var(--nav-spacing-md); /* 2. 設定堆疊間距 */
}

.post-navigation.mobile-stack.divider-enabled.has-both-posts.divider-position-auto .post-nav-divider {
display: block;
order: 3;
}

.post-navigation.mobile-stack.divider-enabled.has-both-posts .nav-previous,
.post-navigation.mobile-stack.divider-enabled.has-both-posts .nav-simple-prev,
.post-navigation.mobile-stack.divider-enabled.has-both-posts .nav-arrow-prev {
order: 1;
}

.post-navigation.mobile-stack.divider-enabled.has-both-posts .nav-center-full,
.post-navigation.mobile-stack.divider-enabled.has-both-posts .nav-simple-center,
.post-navigation.mobile-stack.divider-enabled.has-both-posts .nav-center-button {
order: 2;
}

.post-navigation.mobile-stack.divider-enabled.has-both-posts .nav-next,
.post-navigation.mobile-stack.divider-enabled.has-both-posts .nav-simple-next,
.post-navigation.mobile-stack.divider-enabled.has-both-posts .nav-arrow-next {
order: 4;
}

.post-navigation.mobile-stack.has-both-posts .nav-item {
width: 100%; /* 3. 將導航項目寬度重設為 100% */
}

/* 當只有單一導航項目時，也確保其為單欄 */
.post-navigation.mobile-stack:not(.has-both-posts) {
grid-template-columns: 1fr;
}

/* 手機版並排模式(保持雙欄) */
.post-navigation.mobile-columns.has-both-posts {
grid-template-columns: repeat(2, 1fr) !important;
gap: var(--nav-spacing-sm);
}

/* 手機版並排時縮小字體 */
.post-navigation.mobile-columns .nav-title {
font-size: 14px;
-webkit-line-clamp: 2;
}

.post-navigation.mobile-columns .nav-content {
padding: var(--nav-spacing-sm);
}

.post-navigation.mobile-columns .nav-excerpt {
font-size: 12px;
-webkit-line-clamp: 1;
}

/* 手機版強制上方佈局 */
.layout-mobile-top .nav-main {
flex-direction: column !important;
}

.layout-mobile-top .nav-thumb {
width: 100% !important;
height: auto !important;
}

/* 手機版側邊佈局 */
.layout-mobile-side .mobile-image-left .nav-main {
flex-direction: row !important;
}

.layout-mobile-side .mobile-image-right .nav-main {
flex-direction: row-reverse !important;
}

.layout-mobile-side .nav-thumb {
width: 100px !important;
height: 100px !important;
}

.label-style-arrow .nav-arrow-indicator {
width: 36px;
height: 36px;
}

/* 手機版堆疊模式(由後台設定控制) - 修正 */
.post-navigation.mobile-stack { /* .has-both-posts 已被移除，更通用 */
flex-direction: column; /* 1. 將主軸方向改為垂直 */
gap: var(--nav-spacing-md); /* 2. 設定堆疊間距 */
}

.post-navigation.mobile-stack .nav-item,
.post-navigation.mobile-stack .nav-item:only-child {
width: 100%; /* 3. 將導航項目寬度重設為 100% */
max-width: 100%; /* 4. 同時也要重設 max-width */
margin-left: 0; /* 5. 重置 margin */
}


/* ========== 新增箭頭模式手機版 ========== */
.nav-mode-arrow {
gap: var(--nav-spacing-md);
}

.nav-arrow {
padding: 10px 16px;
font-size: 13px;
}

/* .nav-arrow-text {
display: none; 
} */

.nav-arrow svg {
width: 18px;
height: 18px;
}

.nav-center-button {
padding: 10px 16px;
}

/* .nav-center-text {
display: none; 
} */

.nav-center-button svg {
width: 18px;
height: 18px;
}


}
/* ========== 新增極小螢幕最佳化 ========== */
@media (max-width: 480px) {
.nav-mode-arrow {
gap: var(--nav-spacing-sm);
}

.nav-arrow {
padding: 8px 12px;
}

.nav-center-button {
padding: 8px 12px;
}
}
/* ===================================== */

/* ========================================
   無障礙增強
======================================== */
.nav-item a:focus-visible {
outline: 3px solid var(--nav-primary);
outline-offset: 4px;
}


/* ========================================
   列印樣式
======================================== */
@media print {
.post-navigation {
break-inside: avoid;
box-shadow: none !important;
}

.nav-item {
border: 1px solid #ddd !important;
page-break-inside: avoid;
}

.nav-arrow-indicator,
.keyboard-hint,
.dark-mode-toggle {
display: none !important;
}
}

/* ========================================
   效能最佳化
======================================== */
.post-navigation * {
will-change: auto;
}

.nav-item:hover {
will-change: transform, box-shadow;
}

.nav-thumb img {
content-visibility: auto;
}

/* ========================================
   針對小螢幕裝置的字體最佳化
======================================== */
@media (max-width: 480px) {
.post-navigation .nav-title {
/* 在螢幕寬度小於 480px 時，將標題字體縮小到 15px */
font-size: 15px; 
}

/* 如果您希望在小螢幕上並排顯示時，摘要也少顯示一點 */
.post-navigation.mobile-columns .nav-excerpt {
-webkit-line-clamp: 1; /* 摘要只顯示 1 行 */
}
}

/*
 * 現代化的 Clearfix 技巧
 * 應用於主內容與側邊欄的外層容器
 */
/* #postshow-all::after {
content: ""; 
display: table;  
clear: both; 
}*/

/* 
 * 同時，建議為您的主容器 .container 也加上，確保萬無一失
 */
/*.container::after {
content: "";
display: table;
clear: both;
}*/

/* ========================================
   Header Label Refinement
======================================== */
.post-navigation .nav-label,
.post-navigation .nav-label-text {
min-width: 0;
}

.post-navigation .nav-label-text {
overflow-wrap: anywhere;
word-break: break-word;
}

.label-style-header .nav-label {
display: flex;
align-items: center;
gap: var(--nav-spacing-sm);
width: 100%;
padding: var(--nav-spacing-md);
padding-bottom: var(--nav-spacing-sm);
font-size: 14px;
font-weight: 600;
color: var(--nav-primary);
letter-spacing: 0.05em;
line-height: 1.35;
text-transform: uppercase;
}

.label-style-header.label-text-full .nav-label {
font-size: 13px;
letter-spacing: 0.03em;
}

.label-style-header.label-text-full .nav-label-text {
white-space: normal;
}

.label-style-header.has-label-bottom-line .nav-label {
border-bottom: 1px solid var(--nav-border);
}

.label-style-header.no-label-bottom-line .nav-label {
border-bottom: 0;
padding-bottom: var(--nav-spacing-md);
}

.label-style-header .nav-main {
padding-top: 0;
}

.label-style-header .nav-label-icon {
flex: 0 0 auto;
}

@media (max-width: 768px) {
.label-style-header .nav-label {
padding-right: 12px;
padding-left: 12px;
font-size: 13px;
}
}

@media (max-width: 480px) {
.label-style-header .nav-label {
padding-top: 12px;
padding-bottom: 10px;
letter-spacing: 0.02em;
}
}