/* ============================================
   Fig 编程语言官网 — 样式表
   科技极简 · 暗色/亮色 · 响应式
   ============================================ */

/* --- 变量定义 --- */
:root {
  --bg-primary: #07070d;
  --bg-secondary: #0b0b14;
  --bg-card: #0f0f1e;
  --bg-card-hover: #14142a;
  --bg-nav: rgba(7, 7, 13, 0.9);
  --text-primary: #f5f5ff;
  --text-secondary: #e8e8f0;
  --text-muted: #c8c8d8;
  --accent: #F28C28;
  --accent-glow: rgba(242, 140, 40, 0.15);
  --accent-dim: rgba(242, 140, 40, 0.07);
  --border-color: rgba(255, 255, 255, 0.06);
  --border-light: rgba(255, 255, 255, 0.12);
  --border-accent: rgba(242, 140, 40, 0.25);
  --shadow: 0 2px 40px rgba(0, 0, 0, 0.5);
  --code-bg: #090910;
  --logo-filter: none;
}

[data-theme="light"] {
  --bg-primary: #f5f5f8;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f0f0f5;
  --bg-nav: rgba(245, 245, 248, 0.92);
  --text-primary: #15152e;
  --text-secondary: #555570;
  --text-muted: #8888a0;
  --accent: #d07020;
  --accent-glow: rgba(208, 112, 32, 0.12);
  --accent-dim: rgba(208, 112, 32, 0.05);
  --border-color: rgba(0, 0, 0, 0.04);
  --border-light: rgba(0, 0, 0, 0.08);
  --border-accent: rgba(208, 112, 32, 0.2);
  --shadow: 0 2px 30px rgba(0, 0, 0, 0.06);
  --code-bg: #eeeef2;
  --logo-filter: brightness(0.85);
}

/* --- 重置 & 基础 --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 17px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  transition: background-color 0.4s ease, color 0.4s ease;
}

::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: var(--text-muted); }
::-webkit-scrollbar-thumb:hover { background: var(--text-secondary); }
::selection { background: var(--accent); color: #fff; }

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.3s ease;
}
a:hover { color: var(--text-primary); }

/* --- 导航栏 --- */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  padding: 0 2rem;
  height: 64px;
  display: flex;
  align-items: stretch;
  justify-content: space-between;
  background: var(--bg-nav);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
  transition: background 0.4s ease, transform 0.3s ease;
}

.navbar.hidden { transform: translateY(-100%); }

.navbar .logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: 1px;
  color: var(--text-primary);
  text-transform: uppercase;
}

.navbar .logo img { height: 24px; filter: var(--logo-filter); }

.navbar .nav-links {
  display: flex;
  align-items: stretch;
  gap: 2px;
  list-style: none;
  height: 100%;
}

.navbar .nav-links li {
  display: flex;
  align-items: stretch;
}

.navbar .nav-links a {
  display: flex;
  align-items: center;
  color: var(--text-secondary);
  font-size: 0.92rem;
  font-weight: 500;
  padding: 0 16px;
  transition: all 0.3s ease;
  letter-spacing: 0.5px;
  border-bottom: 2px solid transparent;
}

.navbar .nav-links a:hover {
  color: var(--text-primary);
  background: var(--accent-dim);
  border-bottom-color: var(--accent);
}

.nav-controls {
  display: flex;
  align-items: stretch;
  gap: 2px;
  height: 100%;
}

/* --- 语言切换（下拉菜单） --- */
.lang-dropdown {
  position: relative;
  display: flex;
  align-items: stretch;
  height: 100%;
}

.lang-dropdown-trigger {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 0 10px;
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 0.82rem;
  font-weight: 500;
  transition: all 0.2s ease;
}

.lang-dropdown-trigger:hover {
  background: var(--accent-dim);
  border-bottom-color: var(--accent);
  color: var(--text-primary);
}

.lang-dropdown-trigger .arrow {
  font-size: 0.5rem;
  transition: transform 0.2s ease;
}

.lang-dropdown-trigger .arrow.open {
  transform: rotate(180deg);
}

.lang-dropdown-panel {
  position: absolute;
  top: 100%;
  right: 0;
  min-width: 140px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-top: 2px solid var(--accent);
  box-shadow: var(--shadow);
  z-index: 1001;
  overflow: hidden;
  max-height: 0;
  opacity: 0;
  transition: max-height 0.25s ease, opacity 0.2s ease;
}

.lang-dropdown-panel.open {
  max-height: 300px;
  opacity: 1;
}

.lang-dropdown-item {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 10px 14px;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 0.85rem;
  letter-spacing: 0.5px;
  transition: all 0.15s ease;
  text-align: left;
}

.lang-dropdown-item:hover {
  background: var(--accent-dim);
  color: var(--text-primary);
}

.lang-dropdown-item.active {
  color: var(--accent);
  background: var(--accent-dim);
}

/* --- 主题切换 --- */
.theme-toggle {
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-muted);
  width: 34px;
  cursor: pointer;
  font-size: 0.85rem;
  transition: color 0.2s ease, background 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  color: var(--accent);
  background: var(--accent-dim);
}

/* --- GitHub --- */
.github-link {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  margin-left: 4px;
  border: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.72rem;
  transition: all 0.25s ease;
}

.github-link:hover {
  border-color: var(--border-accent);
  color: var(--text-primary);
}

.github-link svg { width: 12px; height: 12px; }

/* ============== HERO ============== */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 80px 2rem;
  position: relative;
  overflow: hidden;
}

#grid-canvas {
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 100%;
  z-index: 0;
  pointer-events: none;
}

.hero::before {
  content: '';
  position: absolute;
  top: 50%; left: 50%;
  width: 700px; height: 700px;
  transform: translate(-50%, -50%);
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 60%);
  z-index: 0;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
  margin: 0 auto;
}

.hero-title {
  font-size: 5.5rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 1.2rem;
  letter-spacing: 2px;
  opacity: 0;
  transform: scale(0.92);
  animation: heroZoom 1.2s ease forwards 0.2s;
}

.hero-title .hl-accent {
  color: var(--accent);
  text-shadow: 0 0 60px rgba(242, 140, 40, 0.15);
}

.hero-title .hl-light {
  color: var(--text-primary);
  font-weight: 300;
}

.hero-sub {
  font-size: 1rem;
  color: var(--text-muted);
  letter-spacing: 6px;
  font-weight: 300;
  margin-bottom: 3rem;
  opacity: 0;
  animation: heroFadeIn 1s ease forwards 0.6s;
}

.hero-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  opacity: 0;
  animation: heroFadeIn 1s ease forwards 0.9s;
}

.btn {
  padding: 12px 28px;
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.25s ease;
  border: 1px solid var(--border-color);
  background: transparent;
  color: var(--text-secondary);
  letter-spacing: 1px;
  text-transform: uppercase;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.btn-primary:hover {
  background: transparent;
  color: var(--accent);
}

.btn-secondary {
  color: var(--text-muted);
}

.btn-secondary:hover {
  border-color: var(--accent);
  color: var(--text-primary);
  background: var(--accent-dim);
}

.btn-outline {
  color: var(--text-muted);
  border-color: var(--border-light);
}

.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* ============== SECTION DIVIDER ============== */
.section {
  padding: 60px 2rem 80px;
  max-width: 960px;
  margin: 0 auto;
  position: relative;
}

.section + .section {
  border-top: 1px solid var(--border-color);
}

/* ============== SECTION HEADER ============== */
.section-header {
  margin-bottom: 3rem;
  opacity: 0;
  transform: translateY(12px);
  transition: all 0.5s ease;
}

.section-header.visible { opacity: 1; transform: translateY(0); }

.section-header h2 {
  font-size: 1.4rem;
  font-weight: 400;
  letter-spacing: 2px;
  color: var(--text-secondary);
  text-transform: uppercase;
}

.section-header h2 .hl {
  color: var(--accent);
  font-weight: 500;
}

.section-header p {
  color: var(--text-muted);
  font-size: 1.05rem;
  max-width: 640px;
  margin-top: 0.6rem;
  line-height: 1.7;
}

/* ============== FEATURES ============== */
.features-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--border-color);
  border: 1px solid var(--border-color);
}

.feature-card {
  padding: 2rem 2rem;
  background: var(--bg-primary);
  opacity: 0;
  transform: translateY(12px);
  transition: all 0.4s ease;
}

.feature-card.visible { opacity: 1; transform: translateY(0); }

.feature-card:hover { background: var(--bg-card-hover); }

.feature-card h3 {
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 1rem;
  line-height: 1.7;
}

/* ============== CODE ============== */
.code-showcase {
  border: 1px solid var(--border-color);
  overflow: hidden;
}

.code-tabs {
  display: flex;
  border-bottom: 1px solid var(--border-color);
  overflow-x: auto;
}

.code-tab {
  padding: 10px 18px;
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 0.75rem;
  font-weight: 500;
  transition: all 0.25s ease;
  letter-spacing: 1px;
  text-transform: uppercase;
}

.code-tab:hover { color: var(--text-secondary); background: var(--accent-dim); }
.code-tab.active { color: var(--accent); background: var(--accent-dim); }

.code-pane {
  display: none;
  padding: 1.5rem;
  background: var(--code-bg);
  font-family: 'Fira Code', 'Cascadia Code', 'JetBrains Mono', 'Consolas', monospace;
  font-size: 0.85rem;
  line-height: 2;
  overflow-x: auto;
  min-height: 200px;
  max-height: 420px;
  overflow-y: auto;
}

.code-pane.active { display: block; }

.code-pane .code-line {
  opacity: 0;
  transform: translateX(-6px);
  transition: all 0.3s ease;
  white-space: pre-wrap;
  word-break: break-word;
}

.code-pane .code-line.visible { opacity: 1; transform: translateX(0); }

/* 代码着色 — One Dark Mono 固定配色（不随主题变化） */
.code-pane { background: #1a1b26 !important; }
.code-pane .comment { color: #565f89; font-style: italic; }
.code-pane .keyword { color: #bb9af7; }
.code-pane .string { color: #9ece6a; }
.code-pane .number { color: #ff9e64; }
.code-pane .function { color: #7dcfff; }
.code-pane .type { color: #e0af68; }
.code-pane .builtin { color: #73daca; }

/* ============== PIPELINE ============== */
.pipeline-row {
  display: flex;
  justify-content: center;
  align-items: stretch;
  gap: 0;
  flex-wrap: wrap;
}

.pipeline-step {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 1.2rem 1.5rem;
  min-width: 100px;
  flex: 1;
  text-align: center;
  border: 1px solid var(--border-color);
  margin: -1px 0 0 -1px;
  opacity: 0;
  transform: translateY(20px) scale(0.95);
  transition: opacity 0.5s ease, transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.pipeline-step.visible { opacity: 1; transform: translateY(0) scale(1); }

.pipeline-step:hover {
  border-color: var(--border-accent);
  background: var(--accent-dim);
  transform: scale(1.02);
  z-index: 1;
}

.pipeline-step .step-status {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  color: var(--accent);
}

.pipeline-step .step-name {
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 1px;
  color: var(--text-primary);
  text-transform: uppercase;
}

.pipeline-step .step-desc {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.5;
  max-width: 140px;
}

.pipeline-arrow {
  display: flex;
  align-items: center;
  color: var(--text-muted);
  font-size: 0.9rem;
  padding: 0 4px;
  opacity: 0.4;
}

.pipeline-note {
  text-align: center;
  margin-top: 2rem;
  font-size: 0.9rem;
  color: var(--text-muted);
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.7;
}

/* ============== PERFORMANCE ============== */
.perf-env {
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  letter-spacing: 0.5px;
}

.perf-env span {
  padding: 2px 10px;
  border: 1px solid var(--border-color);
}

.perf-group-label {
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-muted);
  letter-spacing: 2px;
  text-transform: uppercase;
  margin: 2rem 0 1rem;
  opacity: 0.6;
}

.perf-group-label:first-of-type {
  margin-top: 0;
}

.perf-row {
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
}

.perf-item {
  text-align: center;
  padding: 1.2rem 1.5rem;
  border: 1px solid var(--border-color);
  min-width: 120px;
  position: relative;
  overflow: hidden;
}

.perf-item .value {
  font-size: 2.2rem;
  font-weight: 200;
  color: var(--accent);
  letter-spacing: 1px;
}

.perf-item .label {
  font-size: 0.72rem;
  color: var(--text-muted);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-top: 4px;
}

/* 性能条形图 */
.perf-item .bar {
  position: absolute;
  bottom: 0;
  left: 0;
  height: 3px;
  background: var(--accent);
  opacity: 0.4;
  transition: width 0.6s ease;
}

.perf-item.fig .bar { background: var(--accent); opacity: 0.7; }
.perf-item.aot .bar { background: #4fc3f7; opacity: 0.3; }

.perf-note {
  text-align: center;
  margin-top: 2rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.7;
}

/* ============== GET STARTED ============== */
.steps-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 0;
  border: 1px solid var(--border-color);
}

.step-card {
  display: flex;
  gap: 1rem;
  padding: 1.5rem;
  margin: -1px 0 0 -1px;
  border: 1px solid var(--border-color);
  opacity: 0;
  transform: translateY(10px);
  transition: all 0.4s ease;
}

.step-card.visible { opacity: 1; transform: translateY(0); }

.step-number {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 300;
  font-size: 0.9rem;
  color: var(--accent);
  border: 1px solid var(--border-accent);
}

.step-card-content h4 {
  font-weight: 500;
  margin-bottom: 0.3rem;
  font-size: 0.95rem;
  letter-spacing: 1px;
  text-transform: uppercase;
}

.step-card-content p {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.7;
}

.step-card-content code {
  background: var(--code-bg);
  padding: 1px 4px;
  font-family: 'Fira Code', monospace;
  font-size: 0.78rem;
  border: 1px solid var(--border-color);
}

/* ============== ROADMAP ============== */
.roadmap-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  justify-content: center;
}

.roadmap-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 18px;
  border: 1px solid var(--border-color);
  opacity: 0;
  transform: translateY(8px);
  transition: all 0.3s ease;
}

.roadmap-item.visible { opacity: 1; transform: translateY(0); }

.roadmap-item .status {
  font-size: 0.75rem;
}

.roadmap-item .status.done { color: #2ed573; }
.roadmap-item .status.wip { color: var(--accent); }
.roadmap-item .status.planned { color: var(--text-muted); }

.roadmap-item .label {
  font-size: 0.85rem;
  letter-spacing: 0.5px;
  color: var(--text-secondary);
}

/* ============== COMMUNITY ============== */
.community-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0;
  border: 1px solid var(--border-color);
}

.community-card {
  padding: 1.5rem 2rem;
  min-width: 140px;
  flex: 1;
  text-align: center;
  border: 1px solid var(--border-color);
  margin: -1px 0 0 -1px;
  transition: all 0.25s ease;
  opacity: 0;
  transform: translateY(8px);
}

.community-card.visible { opacity: 1; transform: translateY(0); }

.community-card:hover { border-color: var(--border-accent); z-index: 1; }

.community-card h4 {
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 0.3rem;
}

.community-card p {
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* ============== FOOTER ============== */
.footer {
  padding: 2.5rem 2rem;
  text-align: center;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
}

.footer p {
  color: var(--text-muted);
  font-size: 0.85rem;
  letter-spacing: 0.5px;
}

.footer a { color: var(--text-muted); }
.footer a:hover { color: var(--accent); }

/* ============== ANIMATIONS ============== */
@keyframes heroZoom {
  0% { opacity: 0; transform: scale(0.92); }
  50% { opacity: 0.4; }
  100% { opacity: 1; transform: scale(1); }
}

@keyframes heroFadeIn {
  0% { opacity: 0; transform: translateY(8px); }
  100% { opacity: 1; transform: translateY(0); }
}

/* ============== RESPONSIVE ============== */
@media (max-width: 768px) {
  html { font-size: 15px; }
  .navbar { padding: 0 1rem; }
  .navbar .nav-links { display: none; }
  .lang-dropdown-panel { right: auto; left: 0; }

  .hero-title { font-size: 3.2rem; letter-spacing: 1px; }
  .hero-sub { font-size: 0.8rem; letter-spacing: 4px; }
  .hero-actions { flex-direction: column; align-items: center; }
  .btn { width: 100%; max-width: 280px; justify-content: center; }

  .section { padding: 50px 1.5rem 60px; }
  .features-grid { grid-template-columns: 1fr; }
  .pipeline-row { flex-direction: column; align-items: center; }
  .pipeline-step { width: 100%; max-width: 300px; }
  .pipeline-arrow { transform: rotate(90deg); }
  .perf-row { gap: 1rem; }
  .perf-item { min-width: 100px; padding: 1rem; }
  .steps-grid { grid-template-columns: 1fr; }
  .community-links { flex-direction: column; }
  .code-pane { padding: 1rem; font-size: 0.8rem; min-height: 180px; }
}