/* ── Design Tokens ── */
:root {
  --bg: #f8fafc;
  --bg-2: #f1f5f9;
  --surface: #ffffff;
  --ink: #0f172a;
  --muted: #64748b;
  --primary: #2563eb;
  --primary-light: #3b82f6;
  --primary-dark: #1d4ed8;
  --accent: #f59e0b;
  --success: #10b981;
  --danger: #ef4444;
  --line: #e2e8f0;
  --radius: 14px;
  --shadow: 0 10px 25px rgba(37, 99, 235, 0.08);
  --shadow-lg: 0 20px 50px rgba(37, 99, 235, 0.12);
  --glass: rgba(255, 255, 255, 0.7);
  --glass-border: rgba(255, 255, 255, 0.5);
  --transition: cubic-bezier(0.4, 0, 0.2, 1);
  --gl-1: rgba(224, 231, 255, 0.7);
  --gl-2: rgba(207, 250, 254, 0.5);
  --gl-3: rgba(219, 234, 254, 0.3);
  --gl-bg-bot: #ffffff;
}

[data-theme="dark"] {
  --bg: #0f172a;
  --bg-2: #1e293b;
  --surface: #1e293b;
  --ink: #f8fafc;
  --muted: #94a3b8;
  --primary: #3b82f6;
  --primary-light: #60a5fa;
  --primary-dark: #2563eb;
  --line: #334155;
  --shadow: 0 10px 25px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 20px 50px rgba(0, 0, 0, 0.5);
  --glass: rgba(30, 41, 59, 0.75);
  --glass-border: rgba(255, 255, 255, 0.08);
  --gl-1: rgba(30, 58, 138, 0.3);
  --gl-2: rgba(8, 145, 178, 0.15);
  --gl-3: rgba(15, 23, 42, 0);
  --gl-bg-bot: #0f172a;
}

/* ── Reset ── */
* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  color: var(--ink);
  font-family: 'Noto Serif TC', 'Source Han Serif TC', serif;
  background:
    radial-gradient(circle at 8% 10%, var(--gl-1) 0, transparent 38%),
    radial-gradient(circle at 90% 0%, var(--gl-2) 0, transparent 22%),
    radial-gradient(circle at 50% 100%, var(--gl-3) 0, transparent 40%),
    linear-gradient(165deg, var(--bg), var(--gl-bg-bot));
  min-height: 100vh;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background 0.4s ease, color 0.4s ease;
}

/* ── Links ── */
a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.2s var(--transition);
}

a:hover {
  text-decoration: underline;
}

/* ── Layout ── */
.container {
  width: min(1120px, calc(100% - 2rem));
  margin: 0 auto;
}

/* ── Header ── */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: var(--glass);
  border-bottom: 1px solid var(--line);
  transition: box-shadow 0.3s var(--transition), background-color 0.4s, border-color 0.4s;
}

.site-header:hover {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.8rem 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--ink);
  transition: opacity 0.2s;
}

.brand:hover {
  text-decoration: none;
  opacity: 0.85;
}

.brand-mark {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: #fff;
  display: grid;
  place-items: center;
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 700;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
  transition: transform 0.3s var(--transition);
}

.brand:hover .brand-mark {
  transform: scale(1.05);
}

.brand-text {
  font-size: 1.05rem;
  font-weight: 600;
}

.menu-toggle {
  display: none;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
  padding: 0.45rem 0.55rem;
  cursor: pointer;
  transition: background 0.2s;
}

.menu-toggle:hover {
  background: var(--bg-2);
}

.site-nav {
  display: flex;
  gap: 0.3rem;
}

.nav-link {
  font-family: 'Space Grotesk', sans-serif;
  padding: 0.45rem 0.85rem;
  border-radius: 999px;
  color: var(--muted);
  font-weight: 500;
  transition: all 0.25s var(--transition);
  position: relative;
}

.nav-link.active,
.nav-link:hover {
  background: rgba(37, 99, 235, 0.08);
  color: var(--primary);
  text-decoration: none;
}

.nav-link.active {
  font-weight: 600;
}

/* ── Theme Toggle ── */
.theme-toggle {
  background: var(--bg-2);
  border: 1px solid var(--line);
  color: var(--ink);
  cursor: pointer;
  padding: 0.35rem 0.65rem;
  border-radius: 999px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.05rem;
  transition: all 0.3s var(--transition);
  margin-left: 0.5rem;
  outline: none;
}

.theme-toggle:hover {
  background: rgba(37, 99, 235, 0.08);
  border-color: var(--primary);
  transform: translateY(-1px);
}

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

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

[data-theme="light"] .theme-toggle .icon-sun,
:root:not([data-theme="dark"]) .theme-toggle .icon-sun {
  display: none;
}

[data-theme="light"] .theme-toggle .icon-moon,
:root:not([data-theme="dark"]) .theme-toggle .icon-moon {
  display: inline-block;
}

/* ── Hero ── */
.hero {
  padding: 3.7rem 0 2.2rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 2rem;
  align-items: center;
}

.hero h1 {
  font-size: clamp(1.9rem, 3.4vw, 3rem);
  line-height: 1.2;
  margin: 0;
  letter-spacing: -0.01em;
}

.hero p {
  color: var(--muted);
  margin: 1rem 0;
  font-size: 1.05rem;
}

.highlight {
  background: linear-gradient(120deg, var(--primary), var(--primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-card {
  background: var(--glass);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 1rem;
  box-shadow: var(--shadow-lg);
  animation: fadeUp 550ms ease both;
}

.fade-up-3d {
  transform: perspective(1000px) rotateY(-5deg) rotateX(5deg);
  transition: transform 0.5s var(--transition);
}

.fade-up-3d:hover {
  transform: perspective(1000px) rotateY(0deg) rotateX(0deg);
}

.hero-card h3 {
  margin-top: 0;
}

.hero-card ul {
  margin: 0;
  padding-left: 1.2rem;
}

/* ── Buttons ── */
.btn-row {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
  margin-top: 1.2rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 1.2rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s var(--transition);
  cursor: pointer;
  letter-spacing: 0.01em;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(37, 99, 235, 0.2);
  text-decoration: none;
}

.btn:active {
  transform: translateY(0);
}

.btn.primary {
  color: #fff;
  background: linear-gradient(120deg, var(--primary), var(--primary-dark));
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.2);
}

.btn.primary:hover {
  box-shadow: 0 8px 24px rgba(37, 99, 235, 0.35);
  background: linear-gradient(120deg, var(--primary-light), var(--primary));
}

.btn.secondary {
  color: var(--ink);
  border-color: var(--line);
  background: var(--glass);
  backdrop-filter: blur(8px);
}

.btn.secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(37, 99, 235, 0.04);
}

.btn.small {
  padding: 0.45rem 0.85rem;
  font-size: 0.9rem;
}

/* ── Sections ── */
.section {
  padding: 1.5rem 0 2.2rem;
}

.section h2 {
  margin-top: 0;
  font-size: 1.6rem;
}

.section-intro {
  color: var(--muted);
  margin-top: -0.3rem;
}

/* ── Grids ── */
.pillar-grid,
.card-grid {
  display: grid;
  gap: 1rem;
}

.pillar-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.card-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

/* ── Cards ── */
.card {
  background: var(--glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow);
  transition: transform 0.35s var(--transition), box-shadow 0.35s var(--transition), border-color 0.35s ease, background-color 0.4s ease;
  animation: fadeUp 560ms ease both;
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  height: 100%;
}

.card>p {
  flex-grow: 1;
}

.card .btn {
  margin-top: auto;
  align-self: flex-start;
}

.card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(37, 99, 235, 0.02), transparent);
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(37, 99, 235, 0.25);
}

.card:hover::after {
  opacity: 1;
}

.card h3 {
  margin-top: 0.2rem;
  margin-bottom: 0.5rem;
}

.card-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.6rem;
}

/* ── Badges ── */
.badge {
  background: rgba(37, 99, 235, 0.1);
  color: var(--primary);
  font-size: 0.8rem;
  padding: 0.2rem 0.65rem;
  border-radius: 999px;
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 600;
}

.badge-ok {
  background: rgba(16, 185, 129, 0.12);
  color: #059669;
}

.badge-warn {
  background: rgba(245, 158, 11, 0.12);
  color: #b45309;
}

.category {
  font-size: 0.84rem;
  color: var(--muted);
}

/* ── Tags ── */
.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0.75rem 0;
}

.tag {
  font-size: 0.76rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.16rem 0.55rem;
  background: var(--bg-2);
  font-family: 'Space Grotesk', sans-serif;
  transition: all 0.2s;
}

.tag:hover {
  border-color: var(--primary);
  color: var(--primary);
}

/* ── Utilities ── */
.link-list {
  margin: 0;
  padding-left: 1.05rem;
}

.link-list li {
  margin: 0.25rem 0;
}

.meta-row {
  color: var(--muted);
  margin-bottom: 0.75rem;
  font-size: 0.88rem;
}

.toolbox {
  display: flex;
  gap: 0.7rem;
  flex-wrap: wrap;
  margin: 1rem 0 1.2rem;
}

.search-input {
  flex: 1;
  min-width: 200px;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(8px);
  border: 2px solid var(--line);
  border-radius: 999px;
  padding: 0.6rem 1rem;
  font-family: inherit;
  transition: border-color 0.3s, box-shadow 0.3s;
}

.search-input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.08);
}

.filter-row {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.filter-btn {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.45rem 0.8rem;
  background: rgba(255, 255, 255, 0.8);
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.25s var(--transition);
}

.filter-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.filter-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.2);
}

.track-card ol {
  margin-top: 0.7rem;
  padding-left: 1.2rem;
}

.timeline {
  display: grid;
  gap: 0.8rem;
}

.timeline article {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0.9rem 1rem;
}

/* ── Footer ── */
.site-footer {
  border-top: 1px solid var(--line);
  margin-top: 2rem;
  padding: 1.2rem 0 1.5rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.site-footer .container {
  display: flex;
  justify-content: space-between;
  gap: 0.7rem;
  flex-wrap: wrap;
}

.empty {
  color: var(--muted);
  background: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(8px);
  border: 1px dashed rgba(37, 99, 235, 0.2);
  border-radius: var(--radius);
  padding: 1.2rem;
}

/* ── Animations ── */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(16px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-12px);
  }

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

/* ── Responsive ── */
@media (max-width: 960px) {

  .hero-grid,
  .pillar-grid,
  .card-grid {
    grid-template-columns: 1fr;
  }

  .menu-toggle {
    display: block;
  }

  .site-nav {
    display: none;
    position: absolute;
    right: 1rem;
    top: 62px;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--line);
    border-radius: 12px;
    padding: 0.5rem;
    box-shadow: var(--shadow-lg);
    flex-direction: column;
    min-width: 170px;
  }

  .site-nav.open {
    display: flex;
    animation: fadeUp 0.2s ease;
  }
}

/* ── Markdown Viewer ── */
.card.markdown {
  padding: 1.15rem 1.2rem;
}

.markdown-body h1,
.markdown-body h2,
.markdown-body h3,
.markdown-body h4,
.markdown-body h5,
.markdown-body h6 {
  font-family: 'Noto Serif TC', 'Source Han Serif TC', serif;
  line-height: 1.25;
}

.markdown-body h1 {
  margin: 0.2rem 0 0.6rem;
  font-size: 1.9rem;
}

.markdown-body h2 {
  margin: 1.2rem 0 0.55rem;
  font-size: 1.45rem;
}

.markdown-body h3 {
  margin: 1.05rem 0 0.45rem;
  font-size: 1.18rem;
}

.markdown-body p {
  margin: 0.65rem 0;
}

.markdown-body ul,
.markdown-body ol {
  margin: 0.65rem 0;
  padding-left: 1.25rem;
}

.markdown-body li {
  margin: 0.25rem 0;
}

.markdown-body code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
  font-size: 0.92em;
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.06rem 0.35rem;
}

.markdown-body pre {
  margin: 0.75rem 0;
  background: #0f172a;
  color: #f8fafc;
  border-radius: 14px;
  padding: 0.85rem 0.95rem;
  overflow-x: auto;
  border: 1px solid rgba(37, 99, 235, 0.28);
}

.markdown-body pre code {
  background: transparent;
  border: none;
  padding: 0;
  color: inherit;
  font-size: 0.9em;
}

.markdown-body hr {
  border: none;
  border-top: 1px solid var(--line);
  margin: 1.05rem 0;
}

.markdown-body blockquote {
  margin: 0.85rem 0;
  padding: 0.75rem 0.85rem;
  border-left: 4px solid var(--primary);
  background: rgba(37, 99, 235, 0.04);
  border-radius: 0 12px 12px 0;
  color: var(--muted);
}

.table-wrap {
  overflow-x: auto;
  margin: 0.8rem 0;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--surface);
}

.markdown-body table {
  width: 100%;
  border-collapse: collapse;
  min-width: 520px;
}

.markdown-body th,
.markdown-body td {
  border-bottom: 1px solid var(--line);
  padding: 0.55rem 0.7rem;
  text-align: left;
  vertical-align: top;
}

.markdown-body thead th {
  background: var(--bg-2);
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 600;
}

/* ── Roadmap ──  */
.pt-0 {
  padding-top: 0 !important;
}

.roadmap {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-top: 1rem;
  position: relative;
}

.roadmap::before {
  content: "";
  position: absolute;
  left: 24px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--primary), rgba(37, 99, 235, 0.08));
  border-radius: 2px;
}

.roadmap-step {
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
  position: relative;
  animation: fadeUp 0.6s ease both;
}

.roadmap-step:nth-child(2) {
  animation-delay: 100ms;
}

.roadmap-step:nth-child(3) {
  animation-delay: 200ms;
}

.roadmap-step:nth-child(4) {
  animation-delay: 300ms;
}

.step-number {
  flex-shrink: 0;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  font-family: 'Space Grotesk', sans-serif;
  font-weight: 700;
  box-shadow: 0 4px 15px rgba(37, 99, 235, 0.3);
  z-index: 1;
  position: relative;
  border: 3px solid #f8fafc;
  transition: transform 0.3s var(--transition);
}

.roadmap-step:hover .step-number {
  transform: scale(1.1);
}

.step-content {
  background: var(--glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--glass-border);
  padding: 1.25rem 1.5rem;
  border-radius: 12px;
  flex-grow: 1;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.04);
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.step-content:hover {
  transform: translateX(5px);
  border-color: var(--primary);
  box-shadow: 0 12px 28px rgba(37, 99, 235, 0.08);
}

.step-content h3 {
  margin: 0 0 0.5rem 0;
  color: var(--primary);
  font-size: 1.2rem;
}

.step-content p {
  margin: 0;
  color: var(--muted);
}

@media (max-width: 600px) {
  .roadmap::before {
    left: 20px;
  }

  .step-number {
    width: 40px;
    height: 40px;
    font-size: 1.2rem;
    left: -2px;
  }

  .step-content {
    padding: 1rem;
  }
}

/* ── Selection ── */
::selection {
  background: rgba(37, 99, 235, 0.15);
  color: var(--ink);
}

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

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

::-webkit-scrollbar-thumb {
  background: rgba(100, 116, 139, 0.3);
  border-radius: 999px;
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(100, 116, 139, 0.5);
}