/* MistStar 官网样式 —— 冷暖双主题 */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --window-bg: #0e0809;
  --panel-bg: #140e10;
  --card-bg: #1c1314;
  --card-bg-hover: #241819;
  --border: #2c2019;
  --text-main: #f7f0ea;
  --text-second: #b3a296;
  --text-muted: #8a786c;
  --accent-a: #fcd34d;
  --accent-b: #f59e0b;
  --accent-c: #ea580c;
  --accent-text: #261204;
  --selection: rgba(251, 191, 36, 0.25);
  --glow: rgba(251, 191, 36, 0.20);
}

body.theme-cold {
  --window-bg: #060b15;
  --panel-bg: #0a1222;
  --card-bg: #111b30;
  --card-bg-hover: #16233c;
  --border: #1e2d4d;
  --text-main: #e9eeff;
  --text-second: #9fb0d0;
  --text-muted: #6b7fa0;
  --accent-a: #c7d2fe;
  --accent-b: #818cf8;
  --accent-c: #6366f1;
  --accent-text: #111833;
  --selection: rgba(99, 102, 241, 0.35);
  --glow: rgba(99, 102, 241, 0.25);
}

html { scroll-behavior: smooth; }

body {
  font-family: "Microsoft YaHei UI", "PingFang SC", "Segoe UI", system-ui, sans-serif;
  background: var(--window-bg);
  color: var(--text-main);
  line-height: 1.7;
  transition: background 0.35s ease, color 0.35s ease;
}

a { color: var(--accent-b); text-decoration: none; transition: color 0.2s ease; }
a:hover { color: var(--accent-a); }

/* ---------- 导航栏 ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(10, 8, 9, 0.82);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
body.theme-cold .nav { background: rgba(6, 11, 21, 0.82); }

.nav-inner {
  max-width: 1080px; margin: 0 auto;
  display: flex; align-items: center; gap: 24px;
  padding: 12px 24px;
}

.brand { display: flex; align-items: center; gap: 10px; }
.brand-logo { width: 28px; height: 28px; }
.brand-name { font-size: 18px; font-weight: 700; letter-spacing: 0.5px; }

.nav-links { display: flex; gap: 22px; flex: 1; }
.nav-links a { color: var(--text-second); font-size: 14px; }
.nav-links a:hover { color: var(--text-main); }

/* ---------- 冷暖切换开关 ---------- */
.theme-toggle {
  display: flex; align-items: center; gap: 8px;
  cursor: pointer; background: none; border: none;
  font-size: 13px; color: var(--text-second);
}
.toggle-track {
  position: relative; width: 44px; height: 20px;
  border-radius: 10px; display: block;
  background: var(--glow);
  transition: background 0.3s ease;
}
.toggle-thumb {
  position: absolute; top: 3px; left: 3px;
  width: 14px; height: 14px; border-radius: 50%;
  background: var(--accent-b);
  transition: left 0.28s cubic-bezier(.4, 0, .2, 1), background 0.3s ease;
  box-shadow: 0 0 10px var(--glow);
}
body.theme-cold .toggle-thumb { left: 27px; }

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden; text-align: center;
  padding: 96px 24px 72px;
}
.hero-glow {
  position: absolute; left: 50%; top: -140px; transform: translateX(-50%);
  width: 720px; height: 420px; pointer-events: none;
  background: radial-gradient(closest-side, var(--glow), transparent 70%);
}
.hero-content { position: relative; }
.hero-logo { width: 112px; height: 112px; margin-bottom: 20px; }
.hero-title {
  font-size: 56px; font-weight: 800; letter-spacing: 2px;
  background: linear-gradient(90deg, var(--accent-a), var(--accent-b), var(--accent-c));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero-slogan {
  margin-top: 8px; font-size: 16px; letter-spacing: 6px; color: var(--text-muted);
}
.hero-desc {
  max-width: 560px; margin: 22px auto 0;
  font-size: 15px; color: var(--text-second);
}
.hero-actions { margin-top: 32px; display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.hero-stats { margin-top: 28px; font-size: 13px; color: var(--text-muted); }
.hero-stats strong { color: var(--accent-b); font-size: 16px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 12px 30px; border-radius: 10px; font-size: 15px; font-weight: 600;
  cursor: pointer; border: none; transition: transform 0.15s ease, box-shadow 0.25s ease, background 0.25s ease;
}
.btn:active { transform: scale(0.97); }
.btn-primary {
  color: var(--accent-text);
  background: linear-gradient(90deg, var(--accent-a), var(--accent-b), var(--accent-c));
  box-shadow: 0 8px 24px var(--glow);
}
.btn-primary:hover { filter: brightness(1.06); box-shadow: 0 10px 30px var(--glow); color: var(--accent-text); }
.btn-ghost {
  color: var(--text-second);
  background: transparent;
  border: 1px solid var(--border);
}
.btn-ghost:hover { color: var(--text-main); border-color: var(--accent-b); }
.btn-lg { padding: 16px 44px; font-size: 16px; }

/* ---------- 区块 ---------- */
.section { max-width: 1080px; margin: 0 auto; padding: 60px 24px; }
.section-title {
  text-align: center; font-size: 28px; font-weight: 700; margin-bottom: 36px;
}
.section-title::after {
  content: ""; display: block; width: 42px; height: 3px; margin: 12px auto 0;
  border-radius: 2px; background: linear-gradient(90deg, var(--accent-a), var(--accent-b));
}

.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
@media (max-width: 760px) { .feature-grid { grid-template-columns: 1fr; } }

.feature-card, .download-card, .about-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 16px; padding: 28px;
  transition: transform 0.2s ease, border-color 0.25s ease, background 0.3s ease;
}
.feature-card:hover { transform: translateY(-4px); border-color: var(--accent-b); background: var(--card-bg-hover); }
.feature-icon { font-size: 30px; margin-bottom: 12px; }
.feature-card h3 { font-size: 17px; margin-bottom: 8px; }
.feature-card p { font-size: 13px; color: var(--text-muted); }

/* ---------- 下载 ---------- */
.download-card {
  display: flex; align-items: center; justify-content: space-between; gap: 20px; flex-wrap: wrap;
  background: linear-gradient(120deg, var(--card-bg), var(--panel-bg));
}
.download-name { font-size: 20px; font-weight: 700; }
.download-version {
  font-size: 12px; color: var(--text-muted); font-weight: 400; margin-left: 8px;
  background: var(--selection); padding: 2px 10px; border-radius: 10px;
}
.download-desc { margin-top: 6px; font-size: 13px; color: var(--text-second); }
.download-hint { margin-top: 16px; text-align: center; font-size: 12px; color: var(--text-muted); }

/* ---------- 关于 ---------- */
.about-card p { font-size: 14px; color: var(--text-second); margin-bottom: 10px; }
.about-card strong { color: var(--text-main); }
.about-thanks { margin-top: 16px !important; color: var(--text-muted) !important; }

/* ---------- 页脚 ---------- */
.footer {
  text-align: center; padding: 32px 24px 40px;
  border-top: 1px solid var(--border);
  font-size: 12px; color: var(--text-muted);
  line-height: 2;
}

/* ---------- 入场动画 ---------- */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(22px); }
  to   { opacity: 1; transform: translateY(0); }
}
.hero-content {
  animation: fadeInUp 0.6s cubic-bezier(.4, 0, .2, 1) both;
}

/* ---------- 滚动渐入（IntersectionObserver 触发 .shown） ---------- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.55s cubic-bezier(.4, 0, .2, 1),
              transform 0.55s cubic-bezier(.4, 0, .2, 1);
  will-change: opacity, transform;
}
.reveal.shown {
  opacity: 1;
  transform: translateY(0);
}
.feature-card.reveal, .download-card.reveal, .about-card.reveal {
  animation: none;
}
.feature-card.reveal.shown { transition-delay: 0s; }
.feature-card.reveal:nth-child(2).shown { transition-delay: 0.08s; }
.feature-card.reveal:nth-child(3).shown { transition-delay: 0.16s; }

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  .hero-content { animation: none; }
  html { scroll-behavior: auto; }
}

/* ---------- Hero 滚动视差 ---------- */
.hero-content {
  transition: opacity 0.25s ease, transform 0.25s ease-out;
}

/* ---------- 回到顶部（回滚）按钮 ---------- */
.back-to-top {
  position: fixed; right: 22px; bottom: 26px; z-index: 60;
  width: 44px; height: 44px; border-radius: 12px; border: 1px solid var(--border);
  background: var(--card-bg); color: var(--text-main);
  font-size: 18px; cursor: pointer;
  opacity: 0; visibility: hidden; transform: translateY(14px);
  transition: opacity 0.3s ease, transform 0.3s cubic-bezier(.4, 0, .2, 1),
              visibility 0.3s, background 0.3s ease;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.35);
}
.back-to-top.visible { opacity: 1; visibility: visible; transform: translateY(0); }
.back-to-top:hover { background: var(--card-bg-hover); border-color: var(--accent-b); }

/* ---------- 滚动条 ---------- */
::-webkit-scrollbar { width: 10px; }
::-webkit-scrollbar-track { background: var(--window-bg); }
::-webkit-scrollbar-thumb {
  background: var(--border); border-radius: 5px;
}
::-webkit-scrollbar-thumb:hover { background: var(--accent-b); }

/* ---------- 导航滚动状态 ---------- */
.nav { transition: box-shadow 0.3s ease, background 0.3s ease; }
.nav.scrolled { box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35); }

/* ---------- 投稿页 ---------- */
.submit-section { max-width: 760px; margin: 0 auto; padding: 56px 24px 72px; }
.submit-hero { text-align: center; margin-bottom: 36px; }
.submit-intro { font-size: 14px; color: var(--text-second); line-height: 1.9; }

.form-row { margin-bottom: 18px; }
.form-row label {
  display: block; font-size: 13px; color: var(--text-second);
  margin-bottom: 8px; font-weight: 600;
}
.form-row .req { color: var(--accent-c); }

.form-row input, .form-row select, .form-row textarea {
  width: 100%; box-sizing: border-box;
  padding: 11px 14px; border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--panel-bg); color: var(--text-main);
  font-size: 14px; font-family: inherit;
  transition: border-color 0.25s ease, box-shadow 0.25s ease;
}
.form-row input:focus, .form-row select:focus, .form-row textarea:focus {
  outline: none; border-color: var(--accent-b);
  box-shadow: 0 0 0 3px var(--selection);
}
.form-row input::placeholder, .form-row textarea::placeholder { color: var(--text-muted); }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
@media (max-width: 640px) { .form-grid { grid-template-columns: 1fr; } }

.form-actions { display: flex; align-items: center; gap: 16px; margin-top: 26px; }
.submit-msg { font-size: 13px; color: var(--text-second); }
.submit-msg.ok { color: #4ade80; }
.submit-msg.err { color: var(--accent-c); }

.submit-banner p { margin-bottom: 0; }

.nav-links a.active { color: var(--text-main); font-weight: 700; }