/* ===== Hush 加速器 - 主题变量 ===== */
:root {
  --bg: #F8F9FC;
  --bg2: #F1F2F7;
  --card: #FFFFFF;
  --text: #11131F;
  --dim: #6B6F82;
  --border: #E4E5EC;
  --border-hover: #C8CAE0;
  --accent: #3B82F6;
  --accent-glow: #3B82F6;
  --accent-light: rgba(59,130,246,0.08);
  --btn-gradient: linear-gradient(135deg, #3B82F6, #6366F1);
  --green: #10B981;
  --green-light: rgba(16,185,129,0.08);
  --radius: 14px;
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.08);
}
.dark {
  --bg: #0C0D15;
  --bg2: #11131F;
  --card: #161829;
  --text: #E4E7F0;
  --dim: #868BA4;
  --border: #1E2030;
  --border-hover: #2E304A;
  --accent: #60A5FA;
  --accent-glow: #60A5FA;
  --accent-light: rgba(59,130,246,0.12);
  --green: #34D399;
  --green-light: rgba(16,185,129,0.12);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.5);
}

/* ===== 全局重置 ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background .3s, color .3s;
  overflow-x: hidden;
}
body::before {
  content: '';
  position: fixed; top: -35%; left: -18%;
  width: 80vw; height: 80vh;
  background: radial-gradient(ellipse, rgba(59,130,246,0.06) 0%, transparent 70%);
  pointer-events: none; z-index: 0;
}
body::after {
  content: '';
  position: fixed; bottom: -30%; right: -12%;
  width: 70vw; height: 70vh;
  background: radial-gradient(ellipse, rgba(139,92,246,0.04) 0%, transparent 70%);
  pointer-events: none; z-index: 0;
}
.grid-overlay {
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  background-image:
    linear-gradient(rgba(255,255,255,0.013) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.013) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 80% 80% at 50% 30%, black 25%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse 80% 80% at 50% 30%, black 25%, transparent 70%);
}
a { color: var(--accent-glow); text-decoration: none; }

/* ===== 导航栏 ===== */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255,255,255,0.82);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  transition: background .3s, border-color .3s;
}
.dark .navbar { background: rgba(12,13,21,0.82); }
.navbar-inner {
  max-width: 1200px; margin: 0 auto; padding: 0 24px;
  height: 68px; display: flex; align-items: center; justify-content: space-between;
}
.nav-logo {
  font-size: 20px; font-weight: 700; color: var(--text);
  display: flex; align-items: center; gap: 10px;
}
.nav-logo .icon {
  width: 34px; height: 34px;
  background: var(--btn-gradient); border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-size: 17px; font-weight: 800;
  box-shadow: 0 2px 8px rgba(59,130,246,.25);
}
.nav-links { display: flex; gap: 36px; list-style: none; }
.nav-links a {
  color: var(--dim); font-size: 14px; font-weight: 500;
  transition: color .25s; position: relative;
}
.nav-links a:hover { color: var(--text); }
.nav-links a::after {
  content: ''; position: absolute; bottom: -4px; left: 0; right: 0;
  height: 2px; background: var(--accent); border-radius: 1px;
  transform: scaleX(0); transition: transform .25s;
}
.nav-links a:hover::after { transform: scaleX(1); }

/* ===== Hero ===== */
.hero {
  padding-top: 190px; padding-bottom: 150px; text-align: center; position: relative;
}
.hero::before {
  content: ''; position: absolute; top: 15%; left: 50%; transform: translateX(-50%);
  width: 650px; height: 650px;
  background: radial-gradient(circle, rgba(59,130,246,0.11) 0%, transparent 70%);
  pointer-events: none;
}
.hero-badge {
  display: inline-flex; align-items: center; gap: 7px;
  background: var(--green-light); color: var(--green);
  border: 1px solid rgba(16,185,129,0.22);
  font-size: 13px; font-weight: 600; padding: 5px 18px;
  border-radius: 20px; margin-bottom: 30px; letter-spacing: 0.5px;
}
.hero-badge .pulse-dot {
  width: 7px; height: 7px; background: var(--green); border-radius: 50%;
  box-shadow: 0 0 10px var(--green);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.4; } }
.hero h1 {
  font-size: 52px; font-weight: 800; line-height: 1.18;
  margin-bottom: 22px; letter-spacing: -0.8px;
}
.hero h1 .gradient-text {
  background: linear-gradient(135deg, var(--accent-glow), #818CF8);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero p {
  font-size: 18px; color: var(--dim);
  max-width: 620px; margin: 0 auto 46px;
}
.btn-hero {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 16px; font-weight: 600; padding: 15px 34px;
  border-radius: 10px; cursor: pointer; border: none;
  transition: all .25s; position: relative;
}
.btn-hero.btn-primary {
  background: var(--btn-gradient); color: #fff;
  box-shadow: 0 4px 28px rgba(59,130,246,0.35);
}
.btn-hero.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 36px rgba(59,130,246,0.5);
}
.btn-hero.btn-outline {
  background: transparent; color: var(--text);
  border: 1px solid var(--border-hover); margin-left: 14px;
}
.btn-hero.btn-outline:hover { border-color: var(--accent); background: var(--accent-light); }

/* ===== 通用区块 ===== */
section { padding: 100px 24px; position: relative; z-index: 1; }
.container { max-width: 1200px; margin: 0 auto; }
.section-header { text-align: center; margin-bottom: 68px; }
.section-label {
  display: inline-block; font-size: 11px; font-weight: 700;
  letter-spacing: 2.5px; text-transform: uppercase;
  color: var(--accent); margin-bottom: 16px;
}
.section-header h2 { font-size: 38px; font-weight: 700; margin-bottom: 12px; letter-spacing: -0.5px; }
.section-header p { font-size: 16px; color: var(--dim); max-width: 520px; margin: 0 auto; }

/* ===== Features ===== */
.features { background: var(--bg2); transition: background .3s; }
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.feature-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 36px 28px; transition: all .25s; position: relative; overflow: hidden;
}
.feature-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 1px;
  background: linear-gradient(90deg, transparent, rgba(59,130,246,0.3), transparent);
  opacity: 0; transition: opacity .25s;
}
.feature-card:hover {
  border-color: var(--border-hover); transform: translateY(-4px); box-shadow: var(--shadow-lg);
}
.feature-card:hover::before { opacity: 1; }
.feature-icon {
  width: 46px; height: 46px;
  background: var(--accent-light); border: 1px solid rgba(59,130,246,0.18);
  border-radius: 10px; display: flex; align-items: center; justify-content: center;
  margin-bottom: 20px; transition: all .25s;
}
.feature-card:hover .feature-icon {
  border-color: rgba(59,130,246,0.4);
  box-shadow: 0 0 22px rgba(59,130,246,0.12);
}
.feature-card h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.feature-card p { font-size: 14px; color: var(--dim); line-height: 1.65; }

/* ===== Steps ===== */
.how-it-works { background: var(--bg); transition: background .3s; }
.steps { display: flex; gap: 20px; justify-content: center; position: relative; }
.steps::before {
  content: ''; position: absolute; top: 44px; left: calc(12% + 80px); right: calc(12% + 80px);
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-hover), var(--border-hover), transparent);
  z-index: 0;
}
.step {
  flex: 1; max-width: 340px; text-align: center;
  padding: 42px 28px; background: var(--card);
  border-radius: var(--radius); border: 1px solid var(--border);
  position: relative; z-index: 1; transition: all .25s;
}
.step:hover { border-color: var(--border-hover); box-shadow: var(--shadow-lg); }
.step-num {
  width: 46px; height: 46px; background: var(--btn-gradient); color: #fff;
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  font-size: 18px; font-weight: 700; margin: 0 auto 18px;
  box-shadow: 0 2px 12px rgba(59,130,246,0.25);
}
.step h4 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.step p { font-size: 14px; color: var(--dim); }

/* ===== Safety ===== */
.safety { background: var(--bg2); transition: background .3s; }
.safety-card {
  max-width: 820px; margin: 0 auto; text-align: center;
  padding: 58px 48px; background: var(--card);
  border: 1px solid var(--border); border-radius: var(--radius); position: relative; overflow: hidden;
}
.safety-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, transparent, var(--green), transparent);
}
.safety-card::after {
  content: ''; position: absolute; top: -80px; left: 50%; transform: translateX(-50%);
  width: 320px; height: 220px;
  background: radial-gradient(ellipse, rgba(16,185,129,0.07) 0%, transparent 70%);
  pointer-events: none;
}
.safety-card .shield-icon {
  width: 56px; height: 56px; margin: 0 auto 22px;
  background: var(--green-light); border: 1px solid rgba(16,185,129,0.22);
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
}
.safety-card h2 { font-size: 28px; font-weight: 700; margin-bottom: 14px; letter-spacing: -0.5px; }
.safety-card > p {
  font-size: 15px; color: var(--dim); max-width: 600px;
  margin: 0 auto 30px; line-height: 1.75;
}
.safety-tags { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; }
.safety-tag {
  background: var(--green-light); border: 1px solid rgba(16,185,129,0.18);
  color: var(--green); padding: 7px 22px; border-radius: 20px;
  font-size: 13px; font-weight: 600; transition: all .25s;
}
.safety-tag:hover {
  background: rgba(16,185,129,0.18); border-color: rgba(16,185,129,0.32);
}

/* ===== Footer ===== */
footer {
  background: var(--bg2); border-top: 1px solid var(--border);
  padding: 46px 24px; text-align: center; color: var(--dim);
  font-size: 13px; position: relative; z-index: 1;
  transition: background .3s, border-color .3s;
}

/* ===== 公告弹窗 ===== */
.announcement-overlay {
  position: fixed; inset: 0; z-index: 9999;
  background: rgba(0,0,0,0.6); backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  display: flex; align-items: center; justify-content: center;
  animation: annFadeIn 0.3s ease;
}
.announcement-overlay.closing { animation: annFadeOut 0.25s ease forwards; }
@keyframes annFadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes annFadeOut { from { opacity: 1; } to { opacity: 0; } }
.announcement-modal {
  background: var(--card); border: 1px solid var(--border); border-radius: 16px;
  width: min(560px, calc(100vw - 40px));
  max-height: min(80vh, 700px);
  display: flex; flex-direction: column;
  box-shadow: 0 24px 80px rgba(0,0,0,0.5);
  animation: annSlideIn 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
}
.announcement-overlay.closing .announcement-modal {
  animation: annSlideOut 0.25s ease forwards;
}
@keyframes annSlideIn {
  from { opacity: 0; transform: translateY(30px) scale(0.96); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}
@keyframes annSlideOut {
  from { opacity: 1; transform: translateY(0) scale(1); }
  to { opacity: 0; transform: translateY(30px) scale(0.96); }
}
.announcement-header {
  display: flex; align-items: center; justify-content: space-between; padding: 22px 28px 0;
}
.announcement-header h2 { font-size: 20px; font-weight: 700; margin: 0; display: flex; align-items: center; gap: 10px; }
.announcement-header h2 .horn { font-size: 22px; }
.announcement-close {
  width: 34px; height: 34px; border-radius: 8px;
  border: 1px solid var(--border); background: transparent; color: var(--dim);
  cursor: pointer; display: flex; align-items: center; justify-content: center;
  transition: all .2s; flex-shrink: 0;
}
.announcement-close:hover { background: var(--accent-light); border-color: var(--border-hover); color: var(--text); }
.announcement-body {
  padding: 20px 28px 24px; overflow-y: auto;
  line-height: 1.7; font-size: 14.5px; color: var(--text);
}
.announcement-body::-webkit-scrollbar { width: 4px; }
.announcement-body::-webkit-scrollbar-thumb { background: var(--border-hover); border-radius: 2px; }
.announcement-body::-webkit-scrollbar-track { background: transparent; }
.announcement-footer {
  padding: 0 28px 22px;
  display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 10px;
}
.announcement-dismiss {
  background: transparent; border: none; color: var(--dim);
  font-size: 13px; cursor: pointer; padding: 6px 12px; border-radius: 6px; transition: all .2s;
}
.announcement-dismiss:hover { color: var(--text); background: var(--accent-light); }
.announcement-btn {
  background: var(--btn-gradient); color: #fff; border: none;
  font-size: 14px; font-weight: 600; padding: 10px 28px;
  border-radius: 8px; cursor: pointer; transition: all .2s;
}
.announcement-btn:hover {
  opacity: 0.9; transform: translateY(-1px);
  box-shadow: 0 4px 18px rgba(59,130,246,0.3);
}
.announcement-date { font-size: 12px; color: var(--dim); opacity: 0.6; margin: 0 0 8px; }

/* ===== 动画 ===== */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}
.feature-card, .step { animation: fadeUp 0.6s ease both; }
.feature-card:nth-child(2) { animation-delay: 0.08s; }
.feature-card:nth-child(3) { animation-delay: 0.16s; }
.feature-card:nth-child(4) { animation-delay: 0.12s; }
.feature-card:nth-child(5) { animation-delay: 0.2s; }
.feature-card:nth-child(6) { animation-delay: 0.24s; }

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  .hero { padding-top: 150px; padding-bottom: 100px; }
  .hero h1 { font-size: 32px; }
  .hero p { font-size: 15px; }
  .features-grid { grid-template-columns: 1fr; }
  .steps { flex-direction: column; align-items: center; }
  .steps::before { display: none; }
  .step { max-width: 100%; }
  .btn-hero.btn-outline { margin-left: 0; margin-top: 12px; }
  .navbar-inner { padding: 0 16px; }
  .nav-links { display: none; }
  .safety-card { padding: 38px 24px; }
  .section-header h2 { font-size: 28px; }
}