/* ============================================================
   Duo Agent PK 官网样式 —— 像素街机暗色主题
   设计要点：
    · 深色竞技场底色 + 像素网格 + 霓虹辉光，突出“格斗游戏”质感
    · 首屏中央超大登录按钮（渐变描边 + 悬浮辉光 + 呼吸动画）
    · 全站响应式：窄屏单列、按钮/标题等比缩放，不变形
   ============================================================ */
:root {
  --bg: #0a0d16;
  --bg2: #10162a;
  --panel: #151b30;
  --line: #2a3554;
  --cyan: #3ce0ff;
  --blue: #4f7dff;
  --pink: #ff5c8a;
  --gold: #ffcf5c;
  --text: #e8edff;
  --muted: #9aa6c8;
}

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

html { scroll-behavior: smooth; }

body {
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Segoe UI", system-ui, sans-serif;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ---------- 背景层：像素网格 + 顶部辉光 ---------- */
.bg-grid {
  position: fixed; inset: 0; z-index: -2;
  background:
    radial-gradient(1200px 500px at 50% -10%, rgba(79, 125, 255, 0.28), transparent 60%),
    radial-gradient(900px 420px at 85% 110%, rgba(255, 92, 138, 0.12), transparent 60%),
    linear-gradient(180deg, #0d1224 0%, var(--bg) 45%, #070a12 100%);
}
.bg-grid::after {
  content: "";
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(60, 224, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(60, 224, 255, 0.05) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: linear-gradient(180deg, rgba(0,0,0,.9), rgba(0,0,0,.25) 70%, transparent);
  -webkit-mask-image: linear-gradient(180deg, rgba(0,0,0,.9), rgba(0,0,0,.25) 70%, transparent);
}
.bg-glow {
  position: fixed; z-index: -1; top: -260px; left: 50%; transform: translateX(-50%);
  width: 900px; height: 420px; border-radius: 50%;
  background: radial-gradient(closest-side, rgba(60, 224, 255, 0.16), transparent);
  filter: blur(20px);
  animation: floatGlow 7s ease-in-out infinite;
}
@keyframes floatGlow {
  0%, 100% { transform: translateX(-50%) translateY(0); opacity: .8; }
  50% { transform: translateX(-50%) translateY(26px); opacity: 1; }
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px clamp(16px, 4vw, 48px);
  background: rgba(10, 13, 22, 0.72);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(42, 53, 84, 0.6);
}
.logo {
  display: flex; align-items: center; gap: 10px;
  text-decoration: none; color: var(--text);
  font-family: "Courier New", monospace; font-weight: 700; letter-spacing: 1px;
}
.logo-sword { font-size: 26px; filter: drop-shadow(0 0 8px rgba(255, 207, 92, 0.8)); }
.logo-text b { color: var(--cyan); text-shadow: 0 0 12px rgba(60, 224, 255, 0.8); }
.site-nav { display: flex; align-items: center; gap: clamp(10px, 2vw, 26px); }
.site-nav a {
  color: var(--muted); text-decoration: none; font-size: 15px; font-weight: 600;
  transition: color .2s;
}
.site-nav a:hover { color: var(--cyan); }
.site-nav .nav-login {
  padding: 9px 18px; border-radius: 10px; color: #0b1020; font-weight: 800;
  background: linear-gradient(135deg, var(--gold), #ffb347);
  box-shadow: 0 0 18px rgba(255, 207, 92, 0.35);
}
.site-nav .nav-login:hover { color: #0b1020; filter: brightness(1.08); }

/* ---------- 首屏 ---------- */
.hero {
  position: relative;
  min-height: calc(100vh - 70px);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  text-align: center; gap: 20px;
  padding: 48px 18px 60px;
}
.hero-badge {
  font-size: 15px; font-weight: 700; letter-spacing: 2px; color: var(--cyan);
  border: 1px solid rgba(60, 224, 255, 0.45); border-radius: 999px;
  padding: 8px 20px; background: rgba(60, 224, 255, 0.07);
}
.hero-title {
  display: flex; flex-wrap: wrap; justify-content: center; gap: clamp(8px, 2vw, 20px);
  font-family: "Courier New", monospace;
  font-size: clamp(44px, 9vw, 108px); line-height: 1; font-weight: 900;
  letter-spacing: 2px;
  text-shadow: 0 4px 0 rgba(0, 0, 0, 0.45);
}
.hero-title .t1 { color: #fff; }
.hero-title .t2 {
  color: var(--cyan);
  text-shadow: 0 0 26px rgba(60, 224, 255, 0.85), 0 4px 0 rgba(0, 0, 0, 0.45);
}
.hero-title .t3 {
  color: var(--pink);
  text-shadow: 0 0 26px rgba(255, 92, 138, 0.85), 0 4px 0 rgba(0, 0, 0, 0.45);
}
.hero-sub {
  max-width: 760px; color: var(--muted); font-size: clamp(15px, 2vw, 18px); line-height: 1.9;
}
.hero-sub b { color: var(--gold); }

/* 中央大登录按钮 + 英雄榜入口 */
.hero-actions { display: flex; flex-direction: column; align-items: center; gap: 16px; margin: 8px 0; }
.btn-board {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 28px; border-radius: 12px;
  text-decoration: none; color: var(--gold); font-weight: 800; font-size: 15px;
  border: 1px solid rgba(255, 207, 92, 0.5);
  background: rgba(255, 207, 92, 0.08);
  transition: all .15s ease;
}
.btn-board:hover { box-shadow: 0 0 20px rgba(255, 207, 92, 0.4); transform: translateY(-2px); color: #ffd98a; }
.btn-login {
  display: inline-flex; align-items: center; gap: 16px;
  padding: 18px clamp(40px, 8vw, 72px);
  border-radius: 18px;
  text-decoration: none; color: #fff;
  background: linear-gradient(160deg, #2b4dff 0%, #7a3cff 55%, #ff4d8f 100%);
  border: 2px solid rgba(255, 255, 255, 0.28);
  box-shadow:
    0 0 0 4px rgba(60, 224, 255, 0.18),
    0 14px 46px rgba(74, 60, 255, 0.55),
    inset 0 1px 0 rgba(255, 255, 255, 0.35);
  animation: breathe 2.4s ease-in-out infinite;
  transition: transform .15s ease;
}
.btn-login:hover { transform: translateY(-3px) scale(1.03); filter: brightness(1.1); }
.btn-login:active { transform: translateY(0) scale(0.99); }
@keyframes breathe {
  0%, 100% { box-shadow: 0 0 0 4px rgba(60,224,255,.18), 0 14px 46px rgba(74,60,255,.55), inset 0 1px 0 rgba(255,255,255,.35); }
  50% { box-shadow: 0 0 0 10px rgba(60,224,255,.06), 0 18px 64px rgba(255,77,143,.6), inset 0 1px 0 rgba(255,255,255,.35); }
}
.btn-icon { font-size: clamp(26px, 4vw, 40px); filter: drop-shadow(0 0 10px rgba(255, 255, 255, 0.7)); }
.btn-text { display: flex; flex-direction: column; align-items: flex-start; line-height: 1.25; }
.btn-text b { font-size: clamp(24px, 4vw, 38px); letter-spacing: 8px; }
.btn-text small { font-size: 13px; opacity: .85; letter-spacing: 1px; }

.hero-note { color: var(--muted); font-size: 13px; }
.hero-stats { display: flex; gap: clamp(14px, 4vw, 46px); margin-top: 12px; }
.stat { display: flex; flex-direction: column; align-items: center; gap: 2px; }
.stat b {
  font-family: "Courier New", monospace; font-size: clamp(24px, 3.4vw, 36px); color: var(--gold);
  text-shadow: 0 0 14px rgba(255, 207, 92, 0.6);
}
.stat span { font-size: 12px; color: var(--muted); }
.scroll-hint { color: var(--muted); font-size: 13px; letter-spacing: 2px; animation: drop 1.6s ease-in-out infinite; }
@keyframes drop { 0%, 100% { transform: translateY(0); opacity: .7; } 50% { transform: translateY(6px); opacity: 1; } }

/* ---------- 通用区块 ---------- */
.section { padding: 84px clamp(16px, 5vw, 60px); text-align: center; }
.section-dark { background: rgba(16, 22, 42, 0.55); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-title { font-size: clamp(24px, 4vw, 38px); font-weight: 900; letter-spacing: 1px; }
.section-title span {
  background: linear-gradient(90deg, var(--cyan), var(--pink));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.section-sub { max-width: 780px; margin: 16px auto 0; color: var(--muted); font-size: 16px; line-height: 1.9; }

/* ---------- 特性网格 ---------- */
.feature-grid {
  margin-top: 44px;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px; max-width: 1160px; margin-left: auto; margin-right: auto;
  text-align: left;
}
.feature {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.04), rgba(255, 255, 255, 0.01));
  border: 1px solid var(--line); border-radius: 16px;
  padding: 26px 24px;
  transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}
.feature:hover {
  transform: translateY(-4px);
  border-color: rgba(60, 224, 255, 0.55);
  box-shadow: 0 12px 34px rgba(60, 224, 255, 0.12);
}
.feature-icon { font-size: 34px; margin-bottom: 12px; }
.feature h3 { font-size: 18px; margin-bottom: 10px; color: #fff; }
.feature p { color: var(--muted); font-size: 14px; line-height: 1.8; }

/* ---------- 地图特色 ---------- */
.map-features {
  margin-top: 40px;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 16px; max-width: 1080px; margin-left: auto; margin-right: auto;
}
.map-item {
  background: var(--panel); border: 1px solid var(--line); border-radius: 14px;
  padding: 22px 16px;
}
.map-item span { font-size: 36px; display: block; margin-bottom: 8px; }
.map-item b { font-size: 17px; color: var(--cyan); }
.map-item p { margin-top: 8px; color: var(--muted); font-size: 13px; line-height: 1.7; }

/* ---------- 截图 ---------- */
.screens {
  margin-top: 40px;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px; max-width: 1280px; margin-left: auto; margin-right: auto;
}
.screens figure {
  background: var(--panel); border: 1px solid var(--line); border-radius: 16px;
  padding: 10px; overflow: hidden;
}
.screens img {
  width: 100%; height: auto; display: block; border-radius: 10px;
  image-rendering: pixelated; aspect-ratio: 8 / 5; object-fit: cover;
  border: 1px solid rgba(255, 255, 255, 0.08);
}
.screens figcaption { padding: 12px 6px 6px; color: var(--muted); font-size: 13px; }

/* ---------- 三步开战 ---------- */
.steps {
  margin-top: 44px;
  display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px; max-width: 1060px; margin-left: auto; margin-right: auto;
  text-align: left;
}
.step {
  position: relative; background: var(--panel); border: 1px solid var(--line);
  border-radius: 16px; padding: 26px 22px;
}
.step b {
  display: inline-flex; align-items: center; justify-content: center;
  width: 42px; height: 42px; margin-bottom: 14px; border-radius: 12px;
  font-family: "Courier New", monospace; font-size: 20px; color: #0b1020; font-weight: 900;
  background: linear-gradient(135deg, var(--gold), #ffb347);
  box-shadow: 0 0 16px rgba(255, 207, 92, 0.4);
}
.step h3 { font-size: 18px; margin-bottom: 10px; }
.step p { color: var(--muted); font-size: 14px; line-height: 1.85; }
#start .hero-actions { margin-top: 44px; }

/* ---------- 页脚 ---------- */
.site-footer { border-top: 1px solid var(--line); padding: 44px 18px 54px; text-align: center; background: #070a12; }
.footer-inner { max-width: 860px; margin: 0 auto; }
.footer-brand {
  font-family: "Courier New", monospace; font-size: 22px; font-weight: 900; letter-spacing: 2px;
  color: var(--cyan); margin-bottom: 14px;
}
.site-footer p { color: var(--muted); font-size: 13px; line-height: 1.9; }
.copyright { margin-top: 14px; opacity: .7; }

/* ---------- 响应式 ---------- */
@media (max-width: 720px) {
  .site-header { flex-wrap: wrap; gap: 10px; justify-content: center; }
  .site-nav { flex-wrap: wrap; justify-content: center; }
  .hero { min-height: auto; padding-top: 70px; }
  .btn-text b { letter-spacing: 4px; }
}

/* ============ 右上角中英文切换按钮 ============ */
.lang-switch {
  position: fixed; top: 14px; right: 18px; z-index: 60;
  padding: 7px 16px; border-radius: 999px;
  font-size: 13px; font-weight: 700; letter-spacing: .5px;
  color: #ffb25e; text-decoration: none;
  background: rgba(13,18,34,.72); border: 1px solid rgba(60,141,255,.4);
  backdrop-filter: blur(6px);
  transition: all .15s;
}
.lang-switch:hover { border-color: #ffb25e; color: #ffd9a0; box-shadow: 0 0 14px rgba(255,178,94,.35); }
@media (max-width: 640px) {
  .lang-switch { top: 8px; right: 10px; padding: 5px 12px; }
  .site-header { padding-right: 64px; }
}