/* ============================================================
   3D印迹 — fdm3d 主题样式
   色系：碳黑 × 熔融橙 × 钛金黄 × 冷钢灰
   工艺感：工业精密 + 层叠可视化 + 走丝运动粒子
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;600&display=swap');

:root {
  /* 背景层次 - 炉渣碳黑暖调 */
  --bg-primary:    #0c0a08;
  --bg-secondary:  #141210;
  --bg-card:       #1c1814;
  --bg-card-hover: #241e18;

  /* 文字 */
  --text-primary:   #edeae6;
  --text-secondary: #a89f94;
  --text-muted:     #6b6058;

  /* 主强调色 - 熔融橙（喷嘴热端灼热感） */
  --accent:       #ff6b35;
  --accent-glow:  rgba(255, 107, 53, 0.35);
  --accent-light: #ff8c5a;

  /* 次强调色 - 钛金黄（加热床金属光泽） */
  --accent2:      #e8b84b;
  --accent2-glow: rgba(232, 184, 75, 0.28);

  /* 第三强调色 - 冷钢灰（冷却后丝材质感） */
  --accent3:      #b0bcc8;

  /* 边框 */
  --border:        #2a2420;
  --border-light:  #3a3028;
  --border-warm:   rgba(255, 107, 53, 0.2);

  /* 圆角 */
  --radius-sm: 8px;
  --radius:    14px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  /* 阴影 */
  --shadow-sm:   0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow:      0 8px 32px rgba(0, 0, 0, 0.5);
  --shadow-lg:   0 16px 48px rgba(0, 0, 0, 0.6);
  --shadow-glow: 0 0 60px var(--accent-glow);

  /* 过渡 */
  --transition:      0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);

  /* 字体 */
  --font-mono: 'JetBrains Mono', 'SF Mono', 'Cascadia Code', 'Consolas', monospace;

  /* 表面 / 滚动条（随主题切换） */
  --surface-overlay: rgba(12, 10, 8, 0.88);
  --surface-overlay-strong: rgba(12, 10, 8, 0.96);
  --shadow-nav: 0 4px 24px rgba(0, 0, 0, 0.6);
  --shadow-drawer: -8px 0 40px rgba(0, 0, 0, 0.7);
  --scrollbar-thumb: #3a3028;
  --scrollbar-track: #0c0a08;
  --nav-link-hover-bg: rgba(255, 255, 255, 0.05);
  --placeholder-gradient: linear-gradient(135deg, #1e1810 0%, #100e0a 100%);
  --placeholder-icon: rgba(255, 255, 255, 0.1);
  --particles-opacity: 1;
  --on-accent: #fff;

  /* 3D 预览（model-viewer） */
  --mv-bg: #0c0a08;
  --mv-exposure: 1;
  --mv-shadow: 1;
  --mv-overlay: rgba(12, 10, 8, 0.75);
}

[data-theme="light"] {
  --bg-primary:    #f7f4f0;
  --bg-secondary:  #efeae4;
  --bg-card:       #ffffff;
  --bg-card-hover: #f5f0ea;

  --text-primary:   #1a1612;
  --text-secondary: #5c544c;
  --text-muted:     #8a8078;

  --accent-glow:  rgba(255, 107, 53, 0.22);
  --accent-light: #e85a28;

  --accent2-glow: rgba(232, 184, 75, 0.35);

  --border:        #e0d8d0;
  --border-light:  #d0c8c0;
  --border-warm:   rgba(255, 107, 53, 0.28);

  --shadow-sm:   0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow:      0 8px 32px rgba(0, 0, 0, 0.08);
  --shadow-lg:   0 16px 48px rgba(0, 0, 0, 0.1);
  --shadow-glow: 0 0 48px var(--accent-glow);

  --surface-overlay: rgba(247, 244, 240, 0.92);
  --surface-overlay-strong: rgba(247, 244, 240, 0.98);
  --shadow-nav: 0 4px 24px rgba(0, 0, 0, 0.08);
  --shadow-drawer: -8px 0 40px rgba(0, 0, 0, 0.1);
  --scrollbar-thumb: #d0c8c0;
  --scrollbar-track: #f7f4f0;
  --nav-link-hover-bg: rgba(0, 0, 0, 0.04);
  --placeholder-gradient: linear-gradient(135deg, #ebe6e0 0%, #f5f2ee 100%);
  --placeholder-icon: rgba(0, 0, 0, 0.06);
  --particles-opacity: 0.42;

  --mv-bg: #e8e2da;
  --mv-exposure: 1.12;
  --mv-shadow: 0.75;
  --mv-overlay: rgba(247, 244, 240, 0.82);
}

/* ============ 重置 ============ */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scrollbar-width: thin;
  scrollbar-color: var(--scrollbar-thumb) var(--scrollbar-track);
  color-scheme: dark;
}

html[data-theme="light"] {
  color-scheme: light;
}

body {
  font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC',
               -apple-system, BlinkMacSystemFont, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ============ 走丝粒子背景 ============ */
#particles-bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
  opacity: var(--particles-opacity);
  transition: opacity var(--transition-slow);
}

/* 横向走丝线段粒子 */
.filament-particle {
  position: absolute;
  height: 2px;
  border-radius: 2px;
  animation: filamentMove linear infinite;
  opacity: 0;
  pointer-events: none;
}

@keyframes filamentMove {
  0% {
    transform: translateX(-120px);
    opacity: 0;
  }
  8% {
    opacity: 0.7;
  }
  85% {
    opacity: 0.3;
  }
  100% {
    transform: translateX(calc(100vw + 120px));
    opacity: 0;
  }
}

/* 浮动的细小丝料颗粒 */
.melt-dot {
  position: absolute;
  border-radius: 50%;
  animation: meltFloat ease-in-out infinite;
  opacity: 0;
}

@keyframes meltFloat {
  0%, 100% {
    transform: translateY(0px) scale(1);
    opacity: 0;
  }
  10% { opacity: 0.6; }
  50% {
    transform: translateY(-30px) scale(1.2);
    opacity: 0.4;
  }
  90% { opacity: 0.1; }
}

/* ============ 导航栏 ============ */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: var(--transition-slow);
}

.navbar.scrolled {
  background: var(--surface-overlay);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border-bottom: 1px solid var(--border);
  padding: 10px 0;
  box-shadow: var(--shadow-nav);
}

.navbar-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 11px;
  text-decoration: none;
  color: var(--text-primary);
  font-weight: 700;
  font-size: 1.22rem;
  letter-spacing: -0.3px;
  transition: var(--transition);
}

.nav-logo .logo-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, var(--accent), #c94a1a);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.15rem;
  color: #fff;
  box-shadow: 0 4px 18px var(--accent-glow);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.nav-logo .logo-icon::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--accent2);
  animation: heatBedPulse 2s ease-in-out infinite;
}

@keyframes heatBedPulse {
  0%, 100% { opacity: 0.3; }
  50% { opacity: 1; }
}

.nav-logo:hover .logo-icon {
  box-shadow: 0 6px 28px var(--accent-glow);
  transform: scale(1.06);
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 6px;
  align-items: center;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  padding: 8px 17px;
  border-radius: 30px;
  font-size: 0.92rem;
  font-weight: 500;
  transition: var(--transition);
  letter-spacing: 0.2px;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--text-primary);
  background: var(--nav-link-hover-bg);
}

.nav-links .btn-nav-cta {
  background: var(--accent);
  color: var(--on-accent);
  font-weight: 600;
  padding: 8px 20px;
  border-radius: 30px;
  box-shadow: 0 4px 16px var(--accent-glow);
  transition: var(--transition);
}

.nav-links .btn-nav-cta:hover {
  background: var(--accent-light);
  box-shadow: 0 6px 24px var(--accent-glow);
  transform: translateY(-1px);
  color: var(--on-accent);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.theme-toggle {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  transition: var(--transition);
  flex-shrink: 0;
}

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

.theme-toggle .theme-icon-dark { display: none; }
.theme-toggle.is-light .theme-icon-light { display: none; }
.theme-toggle.is-light .theme-icon-dark { display: inline; }

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  z-index: 1001;
  padding: 6px;
  background: none;
  border: none;
}

.hamburger span {
  width: 26px;
  height: 2.5px;
  background: var(--text-primary);
  border-radius: 4px;
  transition: var(--transition);
}

.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

/* ============ 主容器 ============ */
.main-container {
  position: relative;
  z-index: 1;
}

section {
  position: relative;
  z-index: 1;
}

/* ============ HERO ============ */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 28px 80px;
  position: relative;
  overflow: hidden;
}

/* 热端橙色 Glow */
.hero-bg-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(160px);
  pointer-events: none;
  z-index: 0;
}

.hero-bg-glow.g1 {
  width: 700px;
  height: 500px;
  top: -10%;
  right: -8%;
  background: radial-gradient(ellipse, rgba(255, 107, 53, 0.3) 0%, transparent 70%);
  animation: heroGlowPulse 7s ease-in-out infinite;
}

.hero-bg-glow.g2 {
  width: 600px;
  height: 600px;
  bottom: -20%;
  left: -15%;
  background: radial-gradient(ellipse, rgba(232, 184, 75, 0.2) 0%, transparent 70%);
  animation: heroGlowPulse 9s ease-in-out infinite 2s;
}

@keyframes heroGlowPulse {
  0%, 100% { transform: scale(1); opacity: 0.8; }
  50% { transform: scale(1.2); opacity: 1; }
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 820px;
}

/* Hero Badge */
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: rgba(255, 107, 53, 0.08);
  border: 1px solid rgba(255, 107, 53, 0.3);
  border-radius: 40px;
  padding: 8px 20px;
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 500;
  letter-spacing: 0.8px;
  margin-bottom: 28px;
  animation: fadeInUp 0.7s ease-out;
  font-family: var(--font-mono);
}

.hero-badge .temp-indicator {
  display: flex;
  align-items: center;
  gap: 5px;
}

.hero-badge .temp-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  animation: tempPulse 1.4s ease-in-out infinite;
}

@keyframes tempPulse {
  0%, 100% {
    box-shadow: 0 0 0 0 var(--accent-glow);
    background: var(--accent);
  }
  50% {
    box-shadow: 0 0 0 8px transparent;
    background: var(--accent-light);
  }
}

/* Hero 标题 */
.hero h1 {
  font-size: clamp(2.6rem, 5.5vw, 4.6rem);
  font-weight: 800;
  letter-spacing: -1.5px;
  line-height: 1.12;
  margin-bottom: 20px;
  animation: fadeInUp 0.7s ease-out 0.1s both;
}

.gradient-text {
  background: linear-gradient(90deg, var(--accent) 0%, var(--accent2) 50%, var(--accent-light) 100%);
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: gradientShift 5s linear infinite;
}

@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.hero-subtitle {
  font-size: 1.12rem;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto 36px;
  animation: fadeInUp 0.7s ease-out 0.2s both;
  letter-spacing: 0.1px;
}

/* Hero 按钮 */
.hero-btns {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
  animation: fadeInUp 0.7s ease-out 0.3s both;
}

/* ============ 按钮系统 ============ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: 40px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  cursor: pointer;
  border: none;
  transition: var(--transition);
  letter-spacing: 0.2px;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), #c94a1a);
  color: #fff;
  box-shadow: 0 6px 28px var(--accent-glow);
  position: relative;
  overflow: hidden;
}

.btn-primary::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(120deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: all 0.6s;
}

.btn-primary:hover::before { left: 100%; }

.btn-primary:hover {
  background: linear-gradient(135deg, var(--accent-light), var(--accent));
  box-shadow: 0 8px 36px var(--accent-glow);
  transform: translateY(-2px);
  color: #fff;
}

.btn-outline {
  background: transparent;
  border: 1.5px solid var(--border-light);
  color: var(--text-primary);
}

.btn-outline:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(255, 107, 53, 0.06);
  transform: translateY(-2px);
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(28px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ============ Hero 层叠可视化 ============ */
.hero-layer-vis {
  margin-top: 52px;
  animation: fadeInUp 0.8s ease-out 0.4s both;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
  position: relative;
}

.layer-stack {
  display: flex;
  flex-direction: column-reverse;
  gap: 3px;
  align-items: center;
}

.layer-bar {
  height: 6px;
  border-radius: 3px;
  background: linear-gradient(90deg, transparent, var(--accent), var(--accent2), var(--accent), transparent);
  opacity: 0;
  transform: scaleX(0);
  animation: layerReveal 0.4s ease-out forwards;
  position: relative;
}

/* 喷嘴光标指示 */
.layer-bar::after {
  content: '';
  position: absolute;
  right: 50%;
  top: -3px;
  width: 4px;
  height: 12px;
  background: var(--accent);
  border-radius: 2px;
  opacity: 0;
  animation: nozzleBlink 0.4s ease-out forwards;
  box-shadow: 0 0 8px var(--accent);
}

@keyframes layerReveal {
  0%   { opacity: 0; transform: scaleX(0); }
  60%  { opacity: 1; transform: scaleX(1.02); }
  100% { opacity: 0.85; transform: scaleX(1); }
}

@keyframes nozzleBlink {
  0%, 60% { opacity: 1; }
  100%    { opacity: 0; }
}

/* 各层动画延迟与宽度（层数越低越宽） */
.layer-bar:nth-child(1)  { width: 200px; animation-delay: 0.5s; }
.layer-bar:nth-child(2)  { width: 196px; animation-delay: 0.7s; }
.layer-bar:nth-child(3)  { width: 190px; animation-delay: 0.9s; }
.layer-bar:nth-child(4)  { width: 184px; animation-delay: 1.1s; }
.layer-bar:nth-child(5)  { width: 178px; animation-delay: 1.3s; }
.layer-bar:nth-child(6)  { width: 170px; animation-delay: 1.5s; }
.layer-bar:nth-child(7)  { width: 160px; animation-delay: 1.7s; }
.layer-bar:nth-child(8)  { width: 148px; animation-delay: 1.9s; }
.layer-bar:nth-child(9)  { width: 134px; animation-delay: 2.1s; }
.layer-bar:nth-child(10) { width: 116px; animation-delay: 2.3s; }
.layer-bar:nth-child(11) { width: 96px;  animation-delay: 2.5s; }
.layer-bar:nth-child(12) { width: 72px;  animation-delay: 2.7s; }

/* 层叠标注 */
.layer-label {
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  letter-spacing: 1.5px;
  animation: fadeInUp 0.6s ease-out 3s both;
}

.layer-label span {
  color: var(--accent);
}

/* ============ 通用区块 ============ */
.section-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 28px;
}

.section-header {
  text-align: center;
  margin-bottom: 56px;
}

.section-tag {
  display: inline-block;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 3px;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 10px;
  font-family: var(--font-mono);
}

.section-title {
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.section-desc {
  color: var(--text-secondary);
  max-width: 520px;
  margin: 0 auto;
  font-size: 1rem;
}

/* ============ 展览作品区 ============ */
.exhibition {
  padding: 80px 0 100px;
}

.works-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 22px;
}

.work-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition-slow);
  cursor: pointer;
  position: relative;
}

.work-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-light);
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg), 0 0 40px rgba(255, 107, 53, 0.08);
}

/* 打印进度条 */
.work-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  transition: width 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  border-radius: 0 0 0 var(--radius-lg);
}

.work-card:hover::after { width: 100%; }

/* 博客卡片同样的底部线 */
.blog-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent2), var(--accent));
  transition: width 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.blog-card:hover::after { width: 100%; }

.work-card-img {
  width: 100%;
  height: 240px;
  object-fit: cover;
  display: block;
  transition: var(--transition-slow);
  background: var(--bg-secondary);
}

.work-card:hover .work-card-img { transform: scale(1.04); }

.work-card-img-placeholder {
  width: 100%;
  height: 240px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3.5rem;
  color: var(--placeholder-icon);
  background: var(--placeholder-gradient);
  position: relative;
  overflow: hidden;
}

.work-card-img-placeholder img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.work-card-img-placeholder::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at center, rgba(255, 107, 53, 0.06) 0%, transparent 70%);
}

.work-card-body {
  padding: 20px 22px 24px;
}

.work-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}

.work-card-tag {
  display: inline-block;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--accent);
  font-weight: 600;
  font-family: var(--font-mono);
  padding: 3px 10px;
  border: 1px solid rgba(255, 107, 53, 0.25);
  border-radius: 20px;
  background: rgba(255, 107, 53, 0.06);
}

.work-card-time {
  font-size: 0.74rem;
  color: var(--accent2);
  font-family: var(--font-mono);
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 4px;
}

.work-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 6px;
  letter-spacing: -0.2px;
  line-height: 1.35;
}

.work-card p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.55;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.work-card-specs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 12px;
}

.wc-spec {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.72rem;
  padding: 4px 10px;
  border-radius: 6px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  font-family: var(--font-mono);
  white-space: nowrap;
}

.wc-spec i {
  font-size: 0.65rem;
  opacity: 0.7;
}

.wc-spec-filament {
  max-width: 220px;
  overflow: hidden;
  text-overflow: ellipsis;
}

.work-card-meta {
  display: flex;
  gap: 16px;
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
  font-size: 0.76rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.work-card-meta span {
  display: flex;
  align-items: center;
  gap: 5px;
}

/* ============ 博客文章区 ============ */
.blog {
  padding: 80px 0 100px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.blog-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 22px;
}

.blog-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 26px 24px;
  transition: var(--transition-slow);
  cursor: pointer;
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 10px;
  overflow: hidden;
}

.blog-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-light);
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.blog-card-date {
  font-size: 0.78rem;
  color: var(--accent2);
  font-weight: 500;
  letter-spacing: 0.5px;
  font-family: var(--font-mono);
}

.blog-card h3 {
  font-size: 1.12rem;
  font-weight: 600;
  letter-spacing: -0.2px;
  line-height: 1.4;
}

.blog-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  flex-grow: 1;
}

.blog-card-readmore {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--accent);
  font-weight: 600;
  font-size: 0.88rem;
  text-decoration: none;
  transition: var(--transition);
  margin-top: 4px;
}

.blog-card-readmore:hover {
  gap: 10px;
  color: var(--accent-light);
}

.blog-card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.blog-card-cat {
  display: inline-block;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 1.2px;
  color: var(--accent);
  font-weight: 600;
  font-family: var(--font-mono);
  padding: 3px 10px;
  border: 1px solid rgba(255, 107, 53, 0.25);
  border-radius: 20px;
  background: rgba(255, 107, 53, 0.06);
}

.blog-card-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 8px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
}

.blog-card-views {
  font-size: 0.76rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  display: flex;
  align-items: center;
  gap: 5px;
}

.blog-card-views i {
  font-size: 0.7rem;
}

/* ============ FDM 技术亮点区 ============ */
.features {
  padding: 80px 0 100px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 22px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  transition: var(--transition-slow);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  opacity: 0;
  transition: var(--transition);
}

.feature-card:hover::before { opacity: 1; }

.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-warm);
  transform: translateY(-4px);
  box-shadow: var(--shadow), 0 0 30px rgba(255, 107, 53, 0.06);
}

.feature-icon {
  width: 62px;
  height: 62px;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 18px;
  font-size: 1.6rem;
  background: rgba(255, 107, 53, 0.1);
  color: var(--accent);
  transition: var(--transition);
  border: 1px solid rgba(255, 107, 53, 0.15);
}

.feature-card:hover .feature-icon {
  background: rgba(255, 107, 53, 0.18);
  box-shadow: 0 0 28px var(--accent-glow);
  border-color: rgba(255, 107, 53, 0.4);
}

.feature-card h4 {
  font-weight: 700;
  margin-bottom: 8px;
  font-size: 1.05rem;
  color: var(--text-primary);
}

.feature-card p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 特征卡片次色标 */
.feature-card.accent2 .feature-icon {
  background: rgba(232, 184, 75, 0.1);
  color: var(--accent2);
  border-color: rgba(232, 184, 75, 0.15);
}

.feature-card.accent2:hover .feature-icon {
  background: rgba(232, 184, 75, 0.18);
  box-shadow: 0 0 28px var(--accent2-glow);
  border-color: rgba(232, 184, 75, 0.4);
}

.feature-card.accent3 .feature-icon {
  background: rgba(176, 188, 200, 0.1);
  color: var(--accent3);
  border-color: rgba(176, 188, 200, 0.15);
}

/* ============ 订阅区 ============ */
.subscribe {
  padding: 80px 0 90px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.subscribe::before {
  content: '';
  position: absolute;
  width: 500px;
  height: 400px;
  border-radius: 50%;
  filter: blur(160px);
  background: radial-gradient(ellipse, rgba(255, 107, 53, 0.18) 0%, transparent 70%);
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
  z-index: 0;
}

.subscribe::after {
  content: '';
  position: absolute;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  filter: blur(120px);
  background: radial-gradient(ellipse, rgba(232, 184, 75, 0.12) 0%, transparent 70%);
  top: 30%;
  right: 15%;
  pointer-events: none;
  z-index: 0;
}

.subscribe-inner {
  position: relative;
  z-index: 1;
  max-width: 520px;
  margin: 0 auto;
}

.subscribe-form {
  display: flex;
  gap: 10px;
  margin-top: 28px;
  flex-wrap: wrap;
  justify-content: center;
}

.subscribe-form input {
  flex: 1;
  min-width: 220px;
  padding: 14px 20px;
  border-radius: 40px;
  border: 1.5px solid var(--border-light);
  background: var(--bg-card);
  color: var(--text-primary);
  font-size: 0.95rem;
  outline: none;
  transition: var(--transition);
  font-family: inherit;
}

.subscribe-form input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(255, 107, 53, 0.1);
}

.subscribe-form input::placeholder { color: var(--text-muted); }

.subscribe-form button {
  padding: 14px 28px;
  border-radius: 40px;
  border: none;
  background: linear-gradient(135deg, var(--accent), #c94a1a);
  color: #fff;
  font-weight: 600;
  cursor: pointer;
  font-size: 0.95rem;
  transition: var(--transition);
  box-shadow: 0 6px 24px var(--accent-glow);
  font-family: inherit;
  white-space: nowrap;
}

.subscribe-form button:hover {
  background: linear-gradient(135deg, var(--accent-light), var(--accent));
  box-shadow: 0 8px 32px var(--accent-glow);
  transform: translateY(-2px);
}

/* ============ 页脚 ============ */
.footer {
  padding: 40px 28px;
  border-top: 1px solid var(--border);
  background: var(--bg-secondary);
  color: var(--text-muted);
  font-size: 0.85rem;
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}

.footer-socials { display: flex; gap: 14px; }

.footer-socials a {
  color: var(--text-muted);
  font-size: 1.2rem;
  transition: var(--transition);
  text-decoration: none;
}

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

/* ============ 打印参数面板 ============ */
.print-params-panel {
  background: linear-gradient(135deg, var(--bg-card) 0%, rgba(28, 20, 16, 0.98) 100%);
  border: 1px solid var(--border-warm);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5), inset 0 0 16px rgba(255, 107, 53, 0.04);
  border-radius: var(--radius);
  padding: 26px;
  position: sticky;
  top: 100px;
  backdrop-filter: blur(10px);
}

.print-params-panel h3 {
  color: var(--accent);
  margin-bottom: 20px;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  text-shadow: 0 0 12px var(--accent-glow);
}

.print-param-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 11px 0;
  border-bottom: 1px dashed var(--border);
  font-size: 0.9rem;
  transition: var(--transition);
}

.print-param-row:last-child { border-bottom: none; }

.print-param-row:hover {
  padding-left: 6px;
  padding-right: 6px;
  background: rgba(255, 107, 53, 0.03);
  border-radius: 6px;
}

.print-param-row span:first-child { color: var(--text-muted); }

.print-param-row span:last-child {
  color: var(--accent);
  font-weight: 600;
  font-family: var(--font-mono);
  font-size: 0.88rem;
}

/* 温度参数特殊色标 */
.print-param-row.temp-hot span:last-child {
  color: var(--accent);
  text-shadow: 0 0 6px var(--accent-glow);
}

.print-param-row.temp-warm span:last-child {
  color: var(--accent2);
}

/* ============ 文章详情布局 ============ */
.post-detail-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 32px;
  max-width: 1280px;
  margin: 0 auto;
  padding: 120px 28px 80px;
}

.post-detail-main {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px;
}

.post-detail-main h1 {
  font-size: 2rem;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.post-detail-meta {
  color: var(--text-muted);
  font-size: 0.88rem;
  margin-bottom: 28px;
  font-family: var(--font-mono);
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

.post-detail-content {
  line-height: 1.85;
}

.post-detail-content h2 {
  font-size: 1.5rem;
  margin: 28px 0 14px;
  color: var(--text-primary);
  border-left: 3px solid var(--accent);
  padding-left: 14px;
}

.post-detail-content h3 {
  font-size: 1.2rem;
  margin: 22px 0 10px;
  color: var(--text-secondary);
}

.post-detail-content code {
  background: rgba(255, 107, 53, 0.08);
  border: 1px solid rgba(255, 107, 53, 0.15);
  border-radius: 5px;
  padding: 2px 7px;
  font-family: var(--font-mono);
  font-size: 0.88em;
  color: var(--accent-light);
}

/* ============ 小型 Hero（内页用）============ */
.page-hero-small {
  padding: 120px 28px 40px;
  text-align: center;
  position: relative;
}

.page-hero-small::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 200px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  opacity: 0.4;
}

/* ============ 导航页 ============ */
.nav-section {
  padding: 0 0 60px;
}

.nav-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
}

a.nav-card {
  position: relative;
  display: block;
  text-decoration: none;
  color: inherit;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  transition: var(--transition-slow);
}

a.nav-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-warm);
  transform: translateY(-4px);
  box-shadow: var(--shadow), 0 0 20px rgba(255, 107, 53, 0.08);
}

.nav-card-icon {
  width: 50px;
  height: 50px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  font-size: 1.35rem;
  background: rgba(255, 107, 53, 0.1);
  color: var(--accent);
  transition: var(--transition);
  border: 1px solid rgba(255, 107, 53, 0.15);
}

a.nav-card:hover .nav-card-icon {
  background: rgba(255, 107, 53, 0.18);
  box-shadow: 0 0 18px var(--accent-glow);
  border-color: rgba(255, 107, 53, 0.4);
}

.nav-card h4 {
  font-weight: 600;
  margin-bottom: 8px;
  font-size: 1.02rem;
}

.nav-card p {
  font-size: 0.87rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 14px;
}

.nav-card-ext-icon {
  position: absolute;
  top: 16px;
  right: 16px;
  font-size: 0.82rem;
  color: var(--text-muted);
  opacity: 0.5;
  transition: var(--transition);
}

a.nav-card-external:hover .nav-card-ext-icon {
  color: var(--accent);
  opacity: 1;
}

.nav-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.nav-tag {
  font-size: 0.72rem;
  padding: 3px 10px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.nav-social-strip {
  display: flex;
  gap: 16px;
  margin-top: 28px;
  justify-content: center;
  flex-wrap: wrap;
}

.nav-social-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: 30px;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  transition: var(--transition);
}

.nav-social-link:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(255, 107, 53, 0.06);
}

.category-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.category-chip {
  padding: 10px 22px;
  border-radius: 30px;
  border: 1px solid var(--border);
  background: var(--bg-card);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  transition: var(--transition);
  font-family: var(--font-mono);
}

.category-chip:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(255, 107, 53, 0.08);
}

/* ============ 通用卡片链接 ============ */
a.work-card, a.blog-card {
  text-decoration: none;
  color: inherit;
  display: block;
}

/* ============ 滚动动画 ============ */
.reveal {
  opacity: 0;
  transform: translateY(36px);
  transition: opacity 0.7s ease-out, transform 0.7s cubic-bezier(0.22, 0.61, 0.36, 1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ============ 响应式 ============ */
@media (max-width: 900px) {
  .post-detail-layout {
    grid-template-columns: 1fr;
  }
  .print-params-panel {
    position: static;
  }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--surface-overlay-strong);
    backdrop-filter: blur(30px);
    -webkit-backdrop-filter: blur(30px);
    flex-direction: column;
    padding: 100px 30px 40px;
    gap: 6px;
    transition: var(--transition-slow);
    border-left: 1px solid var(--border);
    box-shadow: var(--shadow-drawer);
  }

  .nav-links.open { right: 0; }

  .nav-links a {
    display: block;
    padding: 14px 18px;
    font-size: 1rem;
    border-radius: var(--radius-sm);
  }

  .hamburger { display: flex; }

  .hero { padding: 100px 20px 60px; }

  .layer-bar:nth-child(1)  { width: 160px; }
  .layer-bar:nth-child(2)  { width: 156px; }
  .layer-bar:nth-child(3)  { width: 150px; }
  .layer-bar:nth-child(4)  { width: 144px; }
  .layer-bar:nth-child(5)  { width: 138px; }
  .layer-bar:nth-child(6)  { width: 130px; }
  .layer-bar:nth-child(7)  { width: 120px; }
  .layer-bar:nth-child(8)  { width: 108px; }
  .layer-bar:nth-child(9)  { width: 94px;  }
  .layer-bar:nth-child(10) { width: 78px;  }
  .layer-bar:nth-child(11) { width: 60px;  }
  .layer-bar:nth-child(12) { width: 40px;  }

  .works-grid { grid-template-columns: 1fr; }
  .blog-grid  { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr 1fr; }

  .subscribe-form { flex-direction: column; align-items: center; }
  .subscribe-form input { width: 100%; }
}

/* Online tools hub */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: 28px;
}
.tools-loading,
.tools-empty {
  text-align: center;
  padding: 48px 24px;
  color: var(--text-secondary);
}
.tools-empty i {
  font-size: 2.5rem;
  color: var(--text-muted);
  margin-bottom: 16px;
  display: block;
}
a.tool-card {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 32px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-card);
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
a.tool-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent), var(--accent2), var(--accent-light));
  opacity: 1;
}
a.tool-card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent2), var(--accent-light), var(--accent));
  opacity: 0;
  transition: var(--transition);
}
a.tool-card:hover {
  border-color: var(--accent);
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
}
a.tool-card:hover::before {
  opacity: 0;
}
a.tool-card:hover::after {
  opacity: 1;
}
.tool-card-header {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}
.tool-card-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, rgba(255, 107, 53, 0.15), rgba(232, 184, 75, 0.1));
  color: var(--accent);
  font-size: 1.5rem;
  flex-shrink: 0;
  position: relative;
  overflow: hidden;
}
.tool-card-icon::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--accent2);
  animation: heatBedPulse 2s ease-in-out infinite;
}
.tool-card-meta {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.tool-card-meta h4 {
  margin: 0;
  font-size: 1.2rem;
  color: var(--text-primary);
  letter-spacing: -0.2px;
}
.tool-card-desc {
  margin: 0;
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.6;
}
.tool-card-features {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 8px;
}
.tool-feature-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 12px;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  font-size: 0.8rem;
  color: var(--text-secondary);
  transition: var(--transition);
  white-space: nowrap;
}
.tool-feature-item i {
  color: var(--accent);
  font-size: 0.78rem;
}
a.tool-card:hover .tool-feature-item {
  border-color: rgba(255, 107, 53, 0.18);
}
.tool-card-cta {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--accent);
  margin-top: auto;
  padding-top: 4px;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: var(--transition);
}
a.tool-card:hover .tool-card-cta {
  gap: 10px;
}

/* Tool shell (iframe embed) */
body.tool-shell-page .main-container {
  display: none;
}
.tool-shell {
  padding: 100px 24px 24px;
  max-width: 1400px;
  margin: 0 auto;
  min-height: calc(100vh - 80px);
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.tool-shell-header {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 24px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--bg-card);
}
.tool-back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  margin-bottom: 12px;
}
.tool-back-link:hover {
  color: var(--accent);
}
.tool-shell-title {
  margin: 0 0 8px;
  font-size: 1.5rem;
  display: flex;
  align-items: center;
  gap: 12px;
}
.tool-shell-desc {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.95rem;
  max-width: 640px;
}
.btn-tool-open {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 18px;
  border-radius: 8px;
  border: 1px solid var(--border);
  color: var(--text-primary);
  text-decoration: none;
  font-size: 0.9rem;
  transition: var(--transition);
}
.btn-tool-open:hover {
  border-color: var(--accent);
  color: var(--accent);
}
.tool-iframe-wrap {
  flex: 1;
  min-height: calc(100vh - 180px);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  overflow: hidden;
  background: var(--bg-primary);
  position: relative;
}
.tool-iframe {
  width: 100%;
  height: calc(100vh - 180px);
  min-height: 500px;
  border: none;
  display: block;
}
.tool-iframe-fallback {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 32px;
  text-align: center;
  color: var(--text-secondary);
}
.tool-iframe-fallback i {
  font-size: 2rem;
  color: var(--accent2);
}

/* iframe loading spinner */
.tool-iframe-loading {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  color: var(--text-secondary);
  z-index: 2;
  background: var(--bg-primary);
}
.spinner {
  width: 36px;
  height: 36px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

@media (max-width: 480px) {
  .features-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 2.2rem; }
  .post-detail-layout { padding: 100px 16px 60px; }
  .post-detail-main { padding: 24px 18px; }
}