/* ============================================================
   跃烽智能 · YUEFENG AI — Portfolio Stylesheet (v14)
   设计系统:极夜黑 #0A0A0A + 烽火赤 #E84530 + 跃升金橙 #F5A623 + 苍松青 #2D8A4E
   视觉关键词:篝火熔炉 · 木火通明 · 黑夜燃烧
   字体:Noto Sans SC(中) + Inter(英) + JetBrains Mono(代码)
   ============================================================ */

:root {
  /* === 五行修正后色彩系统(黑火青) === */
  --bg-primary:    #0A0A0A;  /* 极夜黑 · 主背景,水之黑压制 */
  --bg-content:    #140F0C;  /* 暖夜黑 · 内容区,比主背景略暖 */
  --bg-secondary:  #1C1410;  /* 暖炭色 · 次背景/卡片底 */
  --bg-elevated:   #2A1E18;  /* 亮炭色 · 卡片 hover */
  --bg-ember:      #1A0A0A;  /* 暗赤黑 · 代码块/特殊容器 */

  --accent-red:    #E84530;  /* 正烽火赤 · 火,核心能量 */
  --accent-red-2:  #C8341F;  /* 烽火赤 hover */
  --accent-orange: #F5A623;  /* 跃升金橙 · 火,温暖活力 */
  --accent-green:  #2D8A4E;  /* 苍松青 · 木,旺运根基 */
  --accent-green-2:#3FAA64;  /* 苍松青亮 */

  --text-primary:  #F5F0EB;  /* 暖白 · 火之余温 */
  --text-secondary:#C4B5A5;  /* 暖灰 · 土金过渡 */
  --text-muted:    #7A6A5C;  /* 弱暖灰 */
  --text-meta:     #5A4D42;  /* meta 暖灰 */

  --border:        rgba(245, 240, 235, 0.08);
  --border-strong: rgba(245, 240, 235, 0.18);
  --border-ember:  rgba(232, 69, 48, 0.25);

  /* 暖光晕阴影(取代冷阴影) */
  --glow-ember:    0 18px 56px rgba(232, 69, 48, 0.20), 0 0 0 1px rgba(232, 69, 48, 0.18);
  --glow-gold:     0 18px 56px rgba(245, 166, 35, 0.18), 0 0 0 1px rgba(245, 166, 35, 0.16);
  --shadow-card:   0 16px 48px rgba(0, 0, 0, 0.55);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --container: 1240px;
  --space-section: 120px;
  --transition: 0.3s cubic-bezier(0.22, 1, 0.36, 1);
}

* { box-sizing: border-box; }
*::selection { background: var(--accent-red); color: var(--text-primary); }

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  margin: 0;
  font-family: "Inter", "Noto Sans SC", -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 15px;
  line-height: 1.65;
  color: var(--text-primary);
  background: var(--bg-primary);
  overflow-x: hidden;
}

/* 暖色径向氛围(取代冷蓝水气) */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background:
    radial-gradient(70% 60% at 82% -10%, rgba(232, 69, 48, 0.12), transparent 65%),
    radial-gradient(55% 45% at 6% 110%, rgba(45, 138, 78, 0.06), transparent 65%);
  pointer-events: none;
  z-index: 0;
}

main, .topbar, .footer { position: relative; z-index: 1; }

h1, h2, h3, h4 {
  font-family: "Inter", "Noto Sans SC", sans-serif;
  letter-spacing: -0.012em;
  line-height: 1.2;
  margin: 0;
}

a { color: inherit; text-decoration: none; transition: color var(--transition); }
ul { margin: 0; padding: 0; list-style: none; }
p { margin: 0; }
strong { color: var(--text-primary); font-weight: 700; }
em { font-style: normal; color: var(--accent-red); }

.fade-init {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1), transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
  will-change: opacity, transform;
}
.fade-in { opacity: 1; transform: none; }

/* ============ Top Navigation ============ */

.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  max-width: var(--container);
  margin: 0 auto;
  padding: 22px 32px;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: rgba(10, 10, 10, 0.78);
  border-bottom: 1px solid var(--border);
}

.brand { display: inline-flex; align-items: center; gap: 12px; }
.brand-mark {
  width: 36px; height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--accent-red), var(--accent-orange));
  color: var(--text-primary);
  display: grid; place-items: center;
  font-family: "Noto Sans SC", sans-serif;
  font-weight: 800; font-size: 18px;
  box-shadow: 0 6px 22px rgba(232, 69, 48, 0.42);
}
.brand-text { display: inline-flex; flex-direction: column; line-height: 1.1; }
.brand-zh { font-family: "Noto Sans SC", sans-serif; font-weight: 700; font-size: 15px; color: var(--text-primary); letter-spacing: 0.04em; }
.brand-en { font-family: "Inter", sans-serif; font-weight: 600; font-size: 11px; color: var(--text-secondary); letter-spacing: 0.18em; margin-top: 2px; }

.nav-links { display: flex; gap: 28px; }
.nav-links a {
  font-size: 14px; font-weight: 500;
  color: var(--text-secondary);
  letter-spacing: 0.02em;
  position: relative;
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -6px;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-red), var(--accent-orange));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}
.nav-links a:hover { color: var(--text-primary); }
.nav-links a:hover::after { transform: scaleX(1); }

.nav-cta {
  font-size: 13px; font-weight: 600;
  padding: 10px 18px;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  color: var(--text-primary);
  transition: all var(--transition);
}
.nav-cta:hover {
  background: var(--accent-red);
  border-color: var(--accent-red);
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(232, 69, 48, 0.42);
}

@media (max-width: 1023px) {
  .nav-links { display: none; }
  .topbar { padding: 16px 22px; }
}

/* ============ Hero (篝火熔炉) ============ */

.hero {
  position: relative;
  max-width: var(--container);
  margin: 0 auto;
  padding: 80px 32px 60px;
  min-height: 78vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  overflow: hidden;
  background: var(--bg-primary);
}

/* 火焰呼吸光晕 — 取代冷蓝脉冲 */
.hero-pulse {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}
.hero-pulse span {
  position: absolute;
  left: 50%;
  top: 60%;
  transform: translate(-50%, -50%);
  border-radius: 50%;
  animation: breathe 5s ease-in-out infinite;
  will-change: transform, opacity;
}
/* 核心赤红 */
.hero-pulse span:nth-child(1) {
  width: 360px; height: 360px;
  background: radial-gradient(circle, rgba(232, 69, 48, 0.85), rgba(232, 69, 48, 0) 65%);
  filter: blur(60px);
  animation-delay: 0s;
}
/* 中层金橙 */
.hero-pulse span:nth-child(2) {
  width: 520px; height: 520px;
  background: radial-gradient(circle, rgba(245, 166, 35, 0.55), rgba(245, 166, 35, 0) 60%);
  filter: blur(100px);
  animation-delay: 1.2s;
}
/* 外层苍松青(木生火之根) */
.hero-pulse span:nth-child(3) {
  width: 760px; height: 760px;
  background: radial-gradient(circle, rgba(45, 138, 78, 0.18), rgba(45, 138, 78, 0) 60%);
  filter: blur(140px);
  animation-delay: 2.4s;
}
/* 极小核心亮点 */
.hero-pulse span:nth-child(4) {
  width: 140px; height: 140px;
  background: radial-gradient(circle, rgba(255, 220, 180, 0.55), rgba(255, 200, 100, 0) 70%);
  filter: blur(30px);
  animation-delay: 0.6s;
}

@keyframes breathe {
  0%, 100% { opacity: 0.55; transform: translate(-50%, -50%) scale(0.85); }
  50%      { opacity: 1;    transform: translate(-50%, -50%) scale(1.12); }
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 880px;
}

.hero-eyebrow {
  display: inline-block;
  font-family: "Inter", sans-serif;
  font-size: 12px;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--accent-orange);
  padding: 6px 14px;
  border: 1px solid var(--border-ember);
  background: rgba(232, 69, 48, 0.06);
  border-radius: 999px;
  margin-bottom: 28px;
}

.hero-title {
  font-family: "Noto Sans SC", "Inter", sans-serif;
  font-size: clamp(48px, 7.5vw, 96px);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.08;
  color: var(--text-primary);
  text-shadow: 0 2px 30px rgba(0, 0, 0, 0.6);
}
.hero-title .line-1, .hero-title .line-2 { display: block; }
.hero-title em {
  background: linear-gradient(135deg, var(--accent-red), var(--accent-orange));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  margin-top: 26px;
  font-size: 19px;
  line-height: 1.65;
  color: var(--text-secondary);
  max-width: 640px;
  text-shadow: 0 1px 20px rgba(0, 0, 0, 0.5);
}

.hero-cta {
  margin-top: 40px;
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.btn-primary, .btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: "Inter", "Noto Sans SC", sans-serif;
  font-size: 14px; font-weight: 600;
  padding: 14px 26px;
  border-radius: 999px;
  transition: all var(--transition);
  cursor: pointer;
  border: 1px solid transparent;
  letter-spacing: 0.02em;
}
.btn-primary {
  background: var(--accent-red);
  color: var(--text-primary);
  box-shadow: 0 12px 32px rgba(232, 69, 48, 0.36);
}
.btn-primary:hover {
  background: linear-gradient(135deg, var(--accent-red), var(--accent-orange));
  transform: translateY(-2px);
  box-shadow: 0 20px 48px rgba(232, 69, 48, 0.50), 0 0 28px rgba(245, 166, 35, 0.30);
}
.btn-primary .arrow { transition: transform var(--transition); }
.btn-primary:hover .arrow { transform: translateX(4px); }
.btn-primary.big { font-size: 15px; padding: 17px 32px; }

.btn-ghost {
  border-color: var(--border-strong);
  color: var(--text-primary);
}
.btn-ghost:hover {
  border-color: var(--accent-orange);
  background: rgba(245, 166, 35, 0.06);
  transform: translateY(-2px);
}

.hero-stats {
  margin-top: 64px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  padding: 28px 0 0;
  border-top: 1px solid var(--border-ember);
  position: relative;
  z-index: 1;
  background: rgba(28, 20, 16, 0.45);
  border-radius: 0;
}
.stat { display: flex; flex-direction: column; gap: 6px; padding: 0 8px; }
.stat-num {
  font-family: "Inter", sans-serif;
  font-size: 42px; font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--accent-red);
  line-height: 1;
}
.stat-num em { font-size: 22px; color: var(--accent-orange); margin-left: 4px; }
.stat-label { font-size: 13px; color: var(--text-secondary); letter-spacing: 0.04em; }

@media (max-width: 1023px) {
  .hero { padding: 60px 22px 40px; min-height: auto; }
  .hero-stats { grid-template-columns: repeat(2, 1fr); margin-top: 48px; }
  .stat-num { font-size: 32px; }
  .hero-pulse span:nth-child(1) { width: 240px; height: 240px; }
  .hero-pulse span:nth-child(2) { width: 360px; height: 360px; }
  .hero-pulse span:nth-child(3) { width: 540px; height: 540px; }
}

/* ============ Section Common (暖炭背景) ============ */

section.why, section.solutions, section.proof,
section.about, section.stack, section.insights, section.contact {
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-section) 32px;
  background: var(--bg-content);
}
section.solutions, section.about, section.insights { background: var(--bg-primary); }

.section-head { max-width: 780px; margin: 0 0 56px; }
.eyebrow {
  display: inline-block;
  font-family: "Inter", sans-serif;
  font-size: 11px;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--accent-orange);
  margin-bottom: 14px;
}
.section-head h2 {
  font-family: "Noto Sans SC", "Inter", sans-serif;
  font-size: clamp(32px, 4.4vw, 54px);
  font-weight: 800;
  letter-spacing: -0.018em;
  color: var(--text-primary);
}
.section-head h2 em {
  background: linear-gradient(135deg, var(--accent-red), var(--accent-orange));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.section-sub { margin-top: 18px; font-size: 17px; color: var(--text-secondary); line-height: 1.7; }

/* ============ Why YUEFENG ============ */

.why-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.why-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 36px 30px;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}
/* 暖光晕 hover(取代冷阴影) */
.why-card:hover {
  transform: translateY(-8px);
  background: var(--bg-elevated);
  border-color: var(--accent-red);
  box-shadow: var(--glow-ember);
}
.why-card.highlight {
  background: linear-gradient(160deg, var(--bg-secondary), var(--bg-ember));
  border-color: var(--border-ember);
}
.why-icon {
  width: 52px; height: 52px;
  border-radius: 14px;
  background: rgba(232, 69, 48, 0.14);
  display: grid; place-items: center;
  color: var(--accent-red);
  margin-bottom: 22px;
  transition: all var(--transition);
}
.why-card:hover .why-icon {
  background: rgba(245, 166, 35, 0.20);
  color: var(--accent-orange);
}
.why-icon svg { width: 28px; height: 28px; }
.why-card h3 {
  font-family: "Noto Sans SC", sans-serif;
  font-size: 26px; font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 14px;
}
.why-line { font-size: 15px; color: var(--text-secondary); margin-bottom: 14px; line-height: 1.65; }
.why-line strong { color: var(--accent-orange); font-weight: 700; }
.why-body { font-size: 14px; color: var(--text-muted); line-height: 1.7; }

@media (max-width: 1023px) {
  .why-grid { grid-template-columns: 1fr; }
}

/* ============ Solutions ============ */

.sol-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.sol-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 40px 36px;
  transition: all var(--transition);
}
.sol-card:hover {
  transform: translateY(-8px);
  background: var(--bg-elevated);
  border-color: var(--accent-orange);
  box-shadow: var(--glow-gold);
}
.sol-num {
  font-family: "JetBrains Mono", monospace;
  font-size: 13px;
  letter-spacing: 0.18em;
  color: var(--accent-orange);
  margin-bottom: 18px;
  display: inline-block;
}
.sol-card h3 {
  font-family: "Noto Sans SC", sans-serif;
  font-size: 28px; font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}
.sol-lead { font-size: 16px; color: var(--text-secondary); line-height: 1.65; margin-bottom: 24px; }
.sol-list { display: flex; flex-direction: column; gap: 10px; margin-bottom: 28px; }
.sol-list li {
  font-size: 14px; color: var(--text-secondary);
  padding-left: 18px; position: relative;
}
.sol-list li::before {
  content: "";
  position: absolute;
  left: 0; top: 9px;
  width: 6px; height: 6px;
  background: var(--accent-red);
  border-radius: 50%;
  box-shadow: 0 0 8px rgba(232, 69, 48, 0.6);
}
.sol-link {
  font-size: 14px; font-weight: 600;
  color: var(--accent-orange);
  display: inline-flex; align-items: center; gap: 8px;
  transition: gap var(--transition), color var(--transition);
}
.sol-link:hover { color: var(--accent-red); gap: 12px; }

@media (max-width: 1023px) { .sol-grid { grid-template-columns: 1fr; } }

/* ============ Social Proof ============ */

.proof-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 72px;
}
.proof-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent-red);
  border-radius: var(--radius-md);
  padding: 36px 30px;
  margin: 0;
  transition: all var(--transition);
}
.proof-card:hover {
  transform: translateY(-6px);
  background: var(--bg-elevated);
  box-shadow: var(--glow-ember);
}
.proof-card.highlight {
  background: linear-gradient(160deg, var(--bg-secondary), var(--bg-ember));
  border-left-color: var(--accent-orange);
}
.quote-mark {
  font-family: "Inter", sans-serif;
  font-size: 64px;
  line-height: 0.6;
  color: var(--accent-red);
  margin-bottom: 12px;
  opacity: 0.7;
  text-shadow: 0 0 24px rgba(232, 69, 48, 0.5);
}
.proof-body {
  font-family: "Noto Sans SC", sans-serif;
  font-size: 17px;
  line-height: 1.7;
  color: var(--text-primary);
  margin-bottom: 22px;
}
.proof-body strong { color: var(--accent-orange); font-weight: 700; }
.proof-meta {
  display: flex; flex-direction: column; gap: 2px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}
.proof-author { font-size: 14px; font-weight: 600; color: var(--text-primary); }
.proof-role { font-size: 12px; color: var(--text-muted); letter-spacing: 0.04em; }

.logo-wall {
  background: var(--bg-ember);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
}
.logo-wall-label {
  font-family: "Inter", sans-serif;
  font-size: 11px;
  letter-spacing: 0.28em;
  color: var(--text-muted);
  margin-bottom: 22px;
  text-align: center;
}
.logo-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 1px;
  background: var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
}
.logo-slot {
  background: var(--bg-secondary);
  padding: 26px 16px;
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 0.04em;
  transition: all var(--transition);
}
.logo-slot:hover { background: var(--bg-elevated); color: var(--accent-orange); }

@media (max-width: 1023px) {
  .proof-grid { grid-template-columns: 1fr; }
  .logo-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ============ About ============ */

.about-grid {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 60px;
  align-items: start;
}
.about-left h2 {
  font-family: "Noto Sans SC", sans-serif;
  font-size: clamp(28px, 3.4vw, 42px);
  font-weight: 700;
  line-height: 1.35;
  color: var(--text-primary);
  margin-bottom: 24px;
}
.about-left h2 em {
  background: linear-gradient(135deg, var(--accent-red), var(--accent-orange));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.about-body {
  font-size: 16px;
  line-height: 1.85;
  color: var(--text-secondary);
  margin-bottom: 18px;
}

.value-list { display: flex; flex-direction: column; gap: 18px; }
.value-list li {
  display: flex;
  align-items: center;
  gap: 22px;
  padding: 22px 24px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: all var(--transition);
}
.value-list li:hover {
  border-color: var(--accent-red);
  background: var(--bg-elevated);
  transform: translateX(4px);
  box-shadow: var(--glow-ember);
}
.value-char {
  width: 52px; height: 52px;
  border-radius: 14px;
  background: linear-gradient(135deg, var(--accent-red), var(--accent-orange));
  display: grid; place-items: center;
  font-family: "Noto Sans SC", serif;
  font-weight: 800;
  font-size: 26px;
  color: var(--text-primary);
  flex-shrink: 0;
  box-shadow: 0 6px 22px rgba(232, 69, 48, 0.35);
}
/* "智"用青绿点缀(木性) */
.value-list li:nth-child(3) .value-char {
  background: linear-gradient(135deg, var(--accent-green), var(--accent-orange));
  box-shadow: 0 6px 22px rgba(45, 138, 78, 0.35);
}
.value-text { font-size: 14px; color: var(--text-secondary); line-height: 1.5; }
.value-text strong { color: var(--text-primary); display: block; margin-bottom: 4px; font-size: 15px; }

@media (max-width: 1023px) {
  .about-grid { grid-template-columns: 1fr; gap: 36px; }
}

/* ============ Tech Stack (暗赤黑底,代码风) ============ */

.stack-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.stack-col {
  background: var(--bg-ember);
  padding: 28px 26px;
  transition: background var(--transition);
}
.stack-col:hover { background: var(--bg-elevated); }
.stack-label {
  font-family: "Inter", sans-serif;
  font-size: 11px;
  letter-spacing: 0.28em;
  color: var(--accent-orange);
  text-transform: uppercase;
  margin-bottom: 10px;
}
.stack-items {
  font-family: "JetBrains Mono", monospace;
  font-size: 14px;
  color: var(--accent-green-2);
  line-height: 1.6;
}

@media (max-width: 1023px) { .stack-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 640px) { .stack-grid { grid-template-columns: 1fr; } }

/* ============ Insights ============ */

.insights-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 36px;
  align-items: stretch;
}
.insight-feature {
  background: linear-gradient(160deg, var(--bg-secondary), var(--bg-ember));
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 40px 36px;
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
  gap: 18px;
  min-height: 240px;
}
.insight-feature:hover {
  border-color: var(--accent-red);
  transform: translateY(-6px);
  box-shadow: var(--glow-ember);
}
.insight-tag {
  display: inline-block;
  align-self: flex-start;
  background: linear-gradient(135deg, var(--accent-red), var(--accent-orange));
  color: var(--text-primary);
  font-size: 11px; font-weight: 700;
  letter-spacing: 0.12em;
  padding: 5px 12px;
  border-radius: 4px;
  text-transform: uppercase;
}
.insight-feature h3 {
  font-family: "Noto Sans SC", sans-serif;
  font-size: 24px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--text-primary);
}
.insight-meta { font-size: 13px; color: var(--text-muted); margin-top: auto; letter-spacing: 0.04em; }

.insight-list { display: flex; flex-direction: column; gap: 14px; }
.insight-list li {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 22px 24px;
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.insight-list li:hover {
  border-color: var(--accent-orange);
  background: var(--bg-elevated);
  transform: translateX(4px);
}
.insight-tag-mini {
  font-family: "Inter", sans-serif;
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent-orange);
}
.insight-list li p {
  font-size: 15px;
  color: var(--text-primary);
  line-height: 1.55;
}

.insights-cta {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-top: 44px;
  font-size: 15px;
  font-weight: 600;
  color: var(--accent-orange);
  padding: 14px 24px;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  transition: all var(--transition);
}
.insights-cta:hover {
  background: linear-gradient(135deg, var(--accent-red), var(--accent-orange));
  border-color: transparent;
  color: var(--text-primary);
  transform: translateY(-2px);
  box-shadow: 0 14px 36px rgba(232, 69, 48, 0.40);
}
.insights-cta .arrow { transition: transform var(--transition); }
.insights-cta:hover .arrow { transform: translateX(4px); }

@media (max-width: 1023px) {
  .insights-grid { grid-template-columns: 1fr; }
}

/* ============ Contact (Hero 火焰光晕呼应) ============ */

.contact { background: var(--bg-primary) !important; }
.contact-card {
  background: linear-gradient(135deg, var(--bg-secondary), var(--bg-ember) 60%, rgba(232, 69, 48, 0.22));
  border: 1px solid var(--border-ember);
  border-radius: var(--radius-lg);
  padding: 64px 56px;
  position: relative;
  overflow: hidden;
}
.contact-card::before {
  content: "";
  position: absolute;
  right: -150px;
  bottom: -150px;
  width: 480px;
  height: 480px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(232, 69, 48, 0.30), rgba(245, 166, 35, 0.10) 50%, transparent 75%);
  filter: blur(60px);
  pointer-events: none;
}
.contact-card h2 {
  font-family: "Noto Sans SC", sans-serif;
  font-size: clamp(34px, 4vw, 52px);
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 14px;
}
.contact-sub {
  font-size: 17px;
  color: var(--text-secondary);
  line-height: 1.7;
  max-width: 640px;
  margin-bottom: 48px;
}
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 56px;
  position: relative;
  z-index: 1;
}
.contact-channels {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 22px;
}
.channel {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 18px 0;
  border-top: 1px solid var(--border);
}
.channel-label {
  font-family: "Inter", sans-serif;
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--text-muted);
  text-transform: uppercase;
}
.channel-value, .channel a {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
}
.channel a:hover { color: var(--accent-orange); }

.contact-cta {
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.contact-tip {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
}
.contact-tip.muted { color: var(--text-muted); font-size: 13px; }

@media (max-width: 1023px) {
  .contact-card { padding: 40px 28px; }
  .contact-grid { grid-template-columns: 1fr; gap: 36px; }
  .contact-channels { grid-template-columns: 1fr; gap: 14px; }
}

/* ============ Footer ============ */

.footer {
  max-width: var(--container);
  margin: 0 auto;
  padding: 80px 32px 36px;
  border-top: 1px solid var(--border);
  background: var(--bg-primary);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 48px;
  margin-bottom: 56px;
}
.footer-brand { display: flex; flex-direction: column; gap: 16px; }
.footer-tagline {
  font-family: "Noto Sans SC", sans-serif;
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
  margin-top: 8px;
}
.footer-mission {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
}
.footer-label {
  font-family: "Inter", sans-serif;
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--accent-orange);
  margin-bottom: 18px;
}
.footer-col ul { display: flex; flex-direction: column; gap: 12px; }
.footer-col ul li { font-size: 14px; color: var(--text-secondary); }
.footer-col ul a:hover { color: var(--accent-red); }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
  font-family: "JetBrains Mono", monospace;
  font-size: 12px;
  color: var(--text-muted);
  letter-spacing: 0.04em;
}

@media (max-width: 1023px) {
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 36px; }
}
@media (max-width: 640px) {
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .footer-bottom { flex-direction: column; gap: 8px; }
}

@media (max-width: 1023px) {
  section.why, section.solutions, section.proof,
  section.about, section.stack, section.insights, section.contact {
    padding: 80px 22px;
  }
  :root { --space-section: 80px; }
}