/* CSS Variables for White-Gold (白金冷調與柔金點綴) Theme */
:root {
  /* Fonts */
  --font-sans: 'Outfit', 'Noto Sans TC', system-ui, -apple-system, sans-serif;
  --font-serif: 'Playfair Display', 'Noto Serif TC', Georgia, serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Theme Colors - Light Mode */
  --color-bg: #f8f9fb;         /* 極淺帶藍白 (platinum-50) */
  --color-bg-alt: #f1f3f6;     /* 淺銀白 (platinum-100) */
  --color-surface: #ffffff;    /* 純白卡片 */
  --color-surface-hover: #ffffff;
  --color-border: #e2e6ec;     /* 銀灰 (platinum-200) */
  --color-text: #1f2937;       /* 深邃冷調 (platinum-800) */
  --color-text-muted: #6b7789; /* 中性冷灰 (platinum-500) */
  --color-text-light: #9ba5b5; /* 冷灰藍 (platinum-400) */
  
  --color-gold-light: #fdfcf9; /* 極淺金白 */
  --color-gold-champagne: #f0e9d8; /* 淡金 */
  --color-accent: #b8a172;     /* 古銅金 (gold-500) */
  --color-accent-hover: #9a7f4e; /* 深金 (gold-600) */
  --color-accent-light: rgba(184, 161, 114, 0.15);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 20px -2px rgba(184, 161, 114, 0.08), 0 2px 8px -1px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 10px 30px -5px rgba(184, 161, 114, 0.12), 0 4px 12px -2px rgba(0, 0, 0, 0.03);

  --bg-grid-color: rgba(148, 163, 184, 0.08);
  --bg-dot-color: rgba(148, 163, 184, 0.15);
}

[data-theme="dark"] {
  /* Theme Colors - Dark Mode */
  --color-bg: #0a0f18;         /* 極深冷黑 (platinum-950) */
  --color-bg-alt: #111827;     /* 接近黑的冷調 (platinum-900) */
  --color-surface: #121a28;    /* 深灰藍卡片 */
  --color-surface-hover: #162032;
  --color-border: #1f2937;     /* 深邃冷調 (platinum-800) */
  --color-text: #f1f3f6;       /* 淺銀白 (platinum-100) */
  --color-text-muted: #9ba5b5; /* 冷灰藍 (platinum-400) */
  --color-text-light: #6b7789; /* 中性冷灰 (platinum-500) */
  
  --color-gold-light: #1f1b13;
  --color-gold-champagne: #3d3120;
  --color-accent: #d4c49a;     /* 柔金 (gold-400) */
  --color-accent-hover: #e5d9bc; /* 香檳金 (gold-300) */
  --color-accent-light: rgba(212, 196, 154, 0.12);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 20px -2px rgba(0, 0, 0, 0.3), 0 2px 8px -1px rgba(212, 196, 154, 0.03);
  --shadow-lg: 0 10px 30px -5px rgba(0, 0, 0, 0.4), 0 4px 12px -2px rgba(212, 196, 154, 0.05);

  --bg-grid-color: rgba(234, 179, 8, 0.03);
  --bg-dot-color: rgba(234, 179, 8, 0.06);
}

/* Global Reset */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.625;
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
}

/* 網格背景與小圓點 (Copied and adapted from globals.css) */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background-image: 
    linear-gradient(to right, var(--bg-grid-color) 1px, transparent 1px),
    linear-gradient(to bottom, var(--bg-grid-color) 1px, transparent 1px);
  background-size: 40px 40px;
  mask-image: radial-gradient(ellipse at center, black, transparent 90%);
  pointer-events: none;
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image: radial-gradient(var(--bg-dot-color) 1px, transparent 1px);
  background-size: 20px 20px;
  mask-image: radial-gradient(ellipse at center, black, transparent 80%);
  pointer-events: none;
  opacity: 0.7;
}

a {
  color: var(--color-text);
  text-decoration: none;
  transition: color 0.2s ease, border-color 0.2s ease;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-light);
}

/* Typography elements */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  font-weight: 300;
  letter-spacing: 0.03em;
  line-height: 1.25;
  color: var(--color-text);
}

/* Header / Navbar */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background-color: rgba(248, 249, 251, 0.75);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: background-color 0.3s, border-color 0.3s;
}

[data-theme="dark"] .navbar {
  background-color: rgba(10, 15, 24, 0.75);
}

.nav-container {
  max-w: 1100px;
  margin: 0 auto;
  padding: 1.25rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 400;
  letter-spacing: 0.05em;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo-accent {
  color: var(--color-accent);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.75rem;
  list-style: none;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 400;
  color: var(--color-text-muted);
  letter-spacing: 0.02em;
  position: relative;
  padding: 0.25rem 0;
}

.nav-link:hover, .nav-link.active {
  color: var(--color-accent);
}

.nav-link::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 1px;
  background-color: var(--color-accent);
  transition: width 0.25s ease;
}

.nav-link:hover::after, .nav-link.active::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.theme-toggle-btn {
  background: none;
  border: 1px solid var(--color-border);
  color: var(--color-text);
  width: 38px;
  height: 38px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.2s, border-color 0.2s, color 0.2s;
}

.theme-toggle-btn:hover {
  background-color: var(--color-bg-alt);
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.theme-toggle-btn svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.theme-toggle-btn .moon-icon {
  display: block;
}

.theme-toggle-btn .sun-icon {
  display: none;
}

[data-theme="dark"] .theme-toggle-btn .moon-icon {
  display: none;
}

[data-theme="dark"] .theme-toggle-btn .sun-icon {
  display: block;
}

/* Hero Section */
.hero {
  padding: 8.5rem 1.5rem 4rem 1.5rem;
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.hero-subtitle {
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--color-accent);
  margin-bottom: 0.75rem;
  font-weight: 500;
  animation: slideUp 0.6s ease-out forwards;
}

.hero-title {
  font-size: 2.75rem;
  font-weight: 300;
  margin-bottom: 1.5rem;
  letter-spacing: 0.02em;
  color: var(--color-text);
  font-family: var(--font-serif);
  animation: slideUp 0.6s ease-out 0.1s forwards;
}

.hero-desc {
  font-size: 1.125rem;
  color: var(--color-text-muted);
  max-width: 600px;
  margin: 0 auto;
  font-weight: 300;
  line-height: 1.75;
  animation: slideUp 0.6s ease-out 0.2s forwards;
}

/* Gold Gradient line Divider */
.gold-divider {
  height: 1px;
  background: linear-gradient(to right, transparent, var(--color-accent), transparent);
  margin: 2.5rem auto;
  width: 60%;
  opacity: 0.5;
}

/* Blog list & controls container */
.container {
  max-width: 950px;
  margin: 0 auto;
  padding: 0 1.5rem 5rem 1.5rem;
}

/* Toolbar: Search and Filter Tags */
.toolbar {
  margin-bottom: 3rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.search-wrapper {
  position: relative;
  width: 100%;
  max-width: 450px;
  margin: 0 auto;
}

.search-input {
  width: 100%;
  padding: 0.8rem 1.2rem 0.8rem 2.8rem;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 99px;
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 0.95rem;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s, background-color 0.2s;
  box-shadow: var(--shadow-sm);
}

.search-input:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-light);
  background-color: var(--color-surface-hover);
}

.search-icon {
  position: absolute;
  left: 1rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-muted);
  width: 16px;
  height: 16px;
  pointer-events: none;
}

.tags-wrapper {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.6rem;
}

.tag-btn {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  padding: 0.4rem 1.1rem;
  border-radius: 99px;
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.2s ease;
  font-weight: 400;
  box-shadow: var(--shadow-sm);
}

.tag-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  transform: translateY(-1px);
}

.tag-btn.active {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-bg);
}

/* Post list grid */
.posts-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.25rem;
}

@media(min-width: 768px) {
  .posts-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* Card */
.post-card {
  background-color: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--color-border);
  border-radius: 16px;
  padding: 2.25rem;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  display: flex;
  flex-direction: column;
  min-height: 280px;
  position: relative;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: var(--shadow-sm);
  cursor: pointer;
}

[data-theme="dark"] .post-card {
  background-color: rgba(18, 26, 40, 0.75);
}

.post-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-accent);
  box-shadow: var(--shadow-lg);
}

.post-meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.825rem;
  color: var(--color-text-light);
  margin-bottom: 1.25rem;
}

.post-meta-item {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.post-meta-item svg {
  width: 14px;
  height: 14px;
}

.post-card-title {
  font-size: 1.45rem;
  font-weight: 300;
  margin-bottom: 0.85rem;
  line-height: 1.35;
  color: var(--color-text);
}

.post-card:hover .post-card-title {
  color: var(--color-accent-hover);
}

.post-card-desc {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  line-height: 1.6;
  margin-bottom: 1.5rem;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
  flex-grow: 1;
}

.post-card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 1.25rem;
  border-t: 1px solid var(--color-border);
}

.post-card-tags {
  display: flex;
  gap: 0.5rem;
}

.post-card-tag {
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  background-color: var(--color-bg-alt);
  color: var(--color-text-muted);
  border-radius: 99px;
  border: 1px solid transparent;
}

.post-card:hover .post-card-tag {
  border-color: var(--color-accent-light);
}

.read-more {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-accent);
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.read-more svg {
  width: 16px;
  height: 16px;
  transition: transform 0.2s ease;
}

.post-card:hover .read-more svg {
  transform: translateX(3px);
}

/* Post Detail styling */
.post-detail-wrapper {
  padding: 8.5rem 1.5rem 4rem 1.5rem;
  max-width: 800px;
  margin: 0 auto;
}

.post-back-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin-bottom: 2.5rem;
  transition: color 0.2s, transform 0.2s;
}

.post-back-btn:hover {
  color: var(--color-accent);
  transform: translateX(-3px);
}

.post-back-btn svg {
  width: 16px;
  height: 16px;
}

.post-header {
  margin-bottom: 3rem;
}

.post-header-title {
  font-size: 2.75rem;
  font-family: var(--font-serif);
  font-weight: 300;
  line-height: 1.25;
  margin-top: 1rem;
  margin-bottom: 1.5rem;
  color: var(--color-text);
}

/* Content Markup Style */
.prose {
  font-size: 1.05rem;
  color: var(--color-text);
  line-height: 1.8;
  letter-spacing: 0.01em;
}

.prose p {
  margin-bottom: 1.75rem;
}

.prose h2 {
  font-family: var(--font-sans);
  font-weight: 400;
  font-size: 1.75rem;
  margin-top: 3rem;
  margin-bottom: 1.25rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text);
}

.prose h3 {
  font-family: var(--font-sans);
  font-weight: 400;
  font-size: 1.4rem;
  margin-top: 2.25rem;
  margin-bottom: 1rem;
}

.prose ul, .prose ol {
  margin-bottom: 1.75rem;
  padding-left: 1.75rem;
}

.prose li {
  margin-bottom: 0.5rem;
}

.prose code {
  font-family: var(--font-mono);
  background-color: var(--color-bg-alt);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-size: 0.9em;
  color: var(--color-accent-hover);
}

.prose pre {
  background-color: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 1.5rem;
  overflow-x: auto;
  margin: 1.75rem 0;
}

.prose pre code {
  background-color: transparent;
  padding: 0;
  border-radius: 0;
  color: var(--color-text);
  font-size: 0.9rem;
}

.prose blockquote {
  border-left: 3px solid var(--color-accent);
  padding-left: 1.5rem;
  color: var(--color-text-muted);
  font-style: italic;
  margin: 2rem 0;
  background-color: var(--color-gold-light);
  padding-top: 0.8rem;
  padding-bottom: 0.8rem;
  border-radius: 0 8px 8px 0;
}

[data-theme="dark"] .prose blockquote {
  background-color: var(--color-gold-champagne);
  opacity: 0.85;
}

.prose strong {
  font-weight: 600;
}

/* Post footer & sharing */
.post-footer {
  margin-top: 4rem;
  padding-top: 2rem;
  border-top: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

@media(min-width: 600px) {
  .post-footer {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
}

.author-info {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.author-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background-color: var(--color-accent-light);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  font-weight: 500;
  border: 1px solid var(--color-accent);
}

.author-meta-name {
  font-weight: 500;
  font-size: 0.95rem;
  color: var(--color-text);
}

.author-meta-title {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

.share-links {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.share-title {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.share-btn {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
  transition: all 0.2s ease;
}

.share-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background-color: var(--color-bg-alt);
}

.share-btn svg {
  width: 16px;
  height: 16px;
}

/* Comment Box Style (LocalStorage dynamic component) */
.comments-section {
  margin-top: 4rem;
  border-top: 1px solid var(--color-border);
  padding-top: 3rem;
}

.comments-title {
  font-size: 1.5rem;
  font-weight: 300;
  margin-bottom: 2rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.comments-title svg {
  width: 20px;
  height: 20px;
  color: var(--color-accent);
}

.comment-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 2.5rem;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  padding: 1.5rem;
  border-radius: 12px;
  box-shadow: var(--shadow-sm);
}

.comment-input-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

@media(min-width: 600px) {
  .comment-input-row {
    grid-template-columns: 1fr 1fr;
  }
}

.comment-field {
  padding: 0.75rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.2s, background-color 0.2s;
}

.comment-field:focus {
  border-color: var(--color-accent);
  background-color: var(--color-surface);
}

textarea.comment-field {
  resize: vertical;
  min-height: 100px;
}

.comment-submit-btn {
  align-self: flex-end;
  background-color: var(--color-accent);
  color: var(--color-bg);
  border: none;
  padding: 0.7rem 1.75rem;
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.2s, transform 0.1s;
}

.comment-submit-btn:hover {
  background-color: var(--color-accent-hover);
}

.comment-submit-btn:active {
  transform: scale(0.98);
}

.comments-list {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  list-style: none;
}

.comment-item {
  display: flex;
  gap: 1rem;
  padding: 1.25rem;
  background-color: rgba(255, 255, 255, 0.4);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  transition: background-color 0.3s;
}

[data-theme="dark"] .comment-item {
  background-color: rgba(18, 26, 40, 0.4);
}

.comment-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: var(--color-accent-light);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 500;
  border: 1px solid var(--color-accent);
  flex-shrink: 0;
}

.comment-content-wrapper {
  flex-grow: 1;
}

.comment-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
}

.comment-author-name {
  font-size: 0.95rem;
  font-weight: 500;
}

.comment-time {
  font-size: 0.75rem;
  color: var(--color-text-light);
}

.comment-text {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  white-space: pre-wrap;
  line-height: 1.5;
}

.comment-delete-btn {
  background: none;
  border: none;
  color: var(--color-text-light);
  cursor: pointer;
  font-size: 0.75rem;
  transition: color 0.2s;
}

.comment-delete-btn:hover {
  color: #ef4444;
}

.no-comments {
  text-align: center;
  padding: 2rem 0;
  color: var(--color-text-light);
  font-style: italic;
  font-size: 0.95rem;
}

/* Footer Section */
.footer {
  border-top: 1px solid var(--color-border);
  padding: 4rem 1.5rem;
  text-align: center;
  background-color: var(--color-bg-alt);
  transition: background-color 0.3s;
}

.footer-container {
  max-width: 950px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
}

.footer-logo {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 400;
  letter-spacing: 0.05em;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
}

.footer-link {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.footer-link:hover {
  color: var(--color-accent);
}

.footer-copy {
  font-size: 0.8rem;
  color: var(--color-text-light);
}

/* Back to Top button */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  box-shadow: var(--shadow-md);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: translateY(10px);
  pointer-events: none;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  z-index: 99;
}

.back-to-top.visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.back-to-top:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  transform: translateY(-2px);
}

.back-to-top svg {
  width: 18px;
  height: 18px;
}

/* Animations */
@keyframes slideUp {
  0% {
    opacity: 0;
    transform: translateY(16px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Reading Progress Bar (top of post pages) */
.reading-progress-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background-color: transparent;
  z-index: 101;
}

.reading-progress-bar {
  height: 100%;
  width: 0%;
  background-color: var(--color-accent);
  transition: width 0.1s ease-out;
}