/* ===== CSS Variables ===== */
:root {
  --bg-primary: #020B2A;
  --bg-card: #0A1A3A;
  --bg-card-hover: #0F2240;
  --cta-gradient: linear-gradient(135deg, #00C8F0, #0080FF);
  --cta-start: #00C8F0;
  --cta-end: #0080FF;
  --text-primary: #FFFFFF;
  --text-secondary: #8899BB;
  --border-color: #1A2B50;
  --login-card-bg: #F5F7FA;
  --radius-card: 12px;
  --radius-btn: 8px;
  --section-padding: 80px 0;
  --card-padding: 24px;
  --cta-glow: 0 0 20px rgba(0, 200, 240, 0.4);
  --header-height: 64px;
}

/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { text-decoration: none; color: inherit; }
ul { list-style: none; }

/* ===== Typography ===== */
h1 { font-size: 48px; font-weight: 700; line-height: 1.2; }
h2 { font-size: 32px; font-weight: 600; line-height: 1.3; }
h3 { font-size: 20px; font-weight: 600; line-height: 1.4; }
h4 { font-size: 15px; font-weight: 600; }
p { color: var(--text-secondary); }

/* ===== Layout ===== */
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section { padding: var(--section-padding); }
.section-header { text-align: center; margin-bottom: 48px; }
.section-header h2 { margin-bottom: 16px; }
.section-header p { max-width: 640px; margin: 0 auto; }

/* ===== Buttons ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 12px 24px; border-radius: var(--radius-btn); font-size: 15px;
  font-weight: 600; cursor: pointer; border: none;
  transition: all 0.2s ease; white-space: nowrap; font-family: inherit;
}
.btn-primary {
  background: var(--cta-gradient); color: #fff; box-shadow: var(--cta-glow);
}
.btn-primary:hover {
  filter: brightness(1.1); box-shadow: 0 0 30px rgba(0,200,240,0.6); transform: translateY(-1px);
}
.btn-outline {
  background: transparent; color: var(--cta-start); border: 1.5px solid var(--cta-start);
}
.btn-outline:hover { background: rgba(0,200,240,0.08); }
.btn-ghost {
  background: transparent; color: var(--text-secondary); border: 1.5px solid var(--border-color);
}
.btn-ghost:hover { background: rgba(255,255,255,0.05); color: var(--text-primary); }
.btn-lg { padding: 14px 32px; font-size: 16px; }
.btn-full { width: 100%; }

/* ===== Header ===== */
.header {
  position: sticky; top: 0; z-index: 100; height: var(--header-height);
  background: rgba(2,11,42,0.88); backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px); border-bottom: 1px solid var(--border-color);
}
.header-inner { display: flex; align-items: center; height: 100%; }

.logo {
  display: flex; align-items: center; gap: 8px; font-size: 17px; font-weight: 700;
  color: var(--text-primary); margin-right: 40px; flex-shrink: 0;
}
.logo-icon {
  width: 32px; height: 32px; background: var(--cta-gradient); border-radius: 8px;
  display: flex; align-items: center; justify-content: center; font-size: 18px;
}

.nav { display: flex; align-items: center; gap: 2px; flex: 1; }
.nav-item { position: relative; }
.nav-link {
  display: flex; align-items: center; gap: 4px; padding: 8px 14px; font-size: 14px;
  font-weight: 500; color: var(--text-secondary); border-radius: 6px;
  transition: all 0.2s; cursor: pointer; background: transparent; border: none;
  font-family: inherit;
}
.nav-link:hover, .nav-link.active { color: var(--text-primary); background: rgba(255,255,255,0.06); }
.nav-link.active { color: var(--cta-start); }

.nav-dropdown {
  position: absolute; top: calc(100% + 8px); left: 0; background: #0D1F3E;
  border: 1px solid var(--border-color); border-radius: 10px; padding: 8px;
  min-width: 180px; opacity: 0; visibility: hidden; transform: translateY(-6px);
  transition: all 0.2s; box-shadow: 0 12px 40px rgba(0,0,0,0.5); z-index: 200;
}
.nav-item:hover .nav-dropdown,
.nav-dropdown:hover { opacity: 1; visibility: visible; transform: translateY(0); }
.nav-dropdown a {
  display: flex; align-items: center; gap: 10px; padding: 10px 12px; font-size: 14px;
  color: var(--text-secondary); border-radius: 6px; transition: all 0.15s;
}
.nav-dropdown a:hover { background: rgba(255,255,255,0.06); color: var(--text-primary); }
.nav-dropdown .p-icon { font-size: 16px; width: 20px; }

.nav-right { display: flex; align-items: center; gap: 10px; margin-left: auto; }

.lang-area { position: relative; }
.lang-btn {
  display: flex; align-items: center; gap: 4px; padding: 6px 12px; font-size: 13px;
  color: var(--text-secondary); background: transparent; border: 1px solid var(--border-color);
  border-radius: 6px; cursor: pointer; font-family: inherit; transition: all 0.2s;
}
.lang-btn:hover { color: var(--text-primary); border-color: rgba(255,255,255,0.3); }
.lang-dropdown {
  position: absolute; top: calc(100% + 8px); right: 0; background: #0D1F3E;
  border: 1px solid var(--border-color); border-radius: 10px; padding: 6px;
  min-width: 150px; opacity: 0; visibility: hidden; transform: translateY(-6px);
  transition: all 0.2s; box-shadow: 0 12px 40px rgba(0,0,0,0.5); z-index: 200;
}
.lang-area:hover .lang-dropdown { opacity: 1; visibility: visible; transform: translateY(0); }
.lang-dropdown a {
  display: flex; align-items: center; gap: 10px; padding: 9px 12px; font-size: 13px;
  color: var(--text-secondary); border-radius: 6px; transition: all 0.15s; text-decoration: none; white-space: nowrap;
}
.lang-dropdown a:hover { background: rgba(255,255,255,0.06); color: var(--text-primary); }
.lang-dropdown a.active { color: var(--cta-start); font-weight: 600; }
.lang-flag { font-size: 15px; width: 20px; text-align: center; }

/* Account dropdown */
.account-area { position: relative; }
.account-area:hover .account-dropdown { opacity: 1; visibility: visible; transform: translateY(0); }
.account-dropdown {
  position: absolute; top: calc(100% + 8px); right: 0; background: #0D1F3E;
  border: 1px solid var(--border-color); border-radius: 10px; padding: 8px;
  min-width: 220px; opacity: 0; visibility: hidden; transform: translateY(-6px);
  transition: all 0.2s; box-shadow: 0 12px 40px rgba(0,0,0,0.5); z-index: 200;
}
.account-info {
  padding: 10px 12px 12px; border-bottom: 1px solid var(--border-color); margin-bottom: 4px;
}
.account-username { font-size: 14px; font-weight: 600; color: var(--text-primary); }
.account-plan { font-size: 12px; color: var(--cta-start); margin-top: 3px; }
.account-dropdown a {
  display: flex; align-items: center; gap: 8px; padding: 9px 12px; font-size: 14px;
  color: var(--text-secondary); border-radius: 6px; transition: all 0.15s;
}
.account-dropdown a:hover { background: rgba(255,255,255,0.06); color: var(--text-primary); }
.account-dropdown .logout { color: #E84A5F; }
.account-dropdown .logout:hover { background: rgba(232,74,95,0.1); color: #E84A5F; }

.hamburger { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 8px; margin-left: auto; }
.hamburger span { display: block; width: 22px; height: 2px; background: var(--text-primary); border-radius: 2px; transition: 0.3s; }

/* ===== Hero ===== */
.hero { padding: 100px 0 80px; position: relative; overflow: hidden; }
.hero::before {
  content: ''; position: absolute; top: -200px; left: -200px; width: 700px; height: 700px;
  background: radial-gradient(circle, rgba(0,128,255,0.12) 0%, transparent 70%); pointer-events: none;
}
.hero::after {
  content: ''; position: absolute; top: -100px; right: -100px; width: 500px; height: 500px;
  background: radial-gradient(circle, rgba(0,200,240,0.08) 0%, transparent 70%); pointer-events: none;
}
.hero-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; position: relative; z-index: 1; }
.hero-tag {
  display: inline-flex; align-items: center; gap: 6px; background: rgba(0,200,240,0.1);
  border: 1px solid rgba(0,200,240,0.25); border-radius: 20px; padding: 4px 14px;
  font-size: 13px; color: var(--cta-start); font-weight: 500; margin-bottom: 20px;
}
.hero-content h1 { font-size: 52px; margin-bottom: 8px; }
.hero-subtitle { font-size: 38px; font-weight: 700; background: var(--cta-gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; margin-bottom: 20px; line-height: 1.2; }
.hero-desc { font-size: 16px; margin-bottom: 32px; max-width: 460px; line-height: 1.8; }
.hero-badges { display: flex; gap: 20px; margin-top: 24px; flex-wrap: wrap; }
.hero-badge { display: flex; align-items: center; gap: 6px; font-size: 13px; color: var(--text-secondary); }
.hero-badge::before { content: ''; width: 6px; height: 6px; border-radius: 50%; background: var(--cta-start); flex-shrink: 0; }

.hero-visual { display: flex; align-items: center; justify-content: center; }
.hero-placeholder {
  width: 100%; aspect-ratio: 4/3; background: linear-gradient(135deg, rgba(0,200,240,0.08), rgba(0,128,255,0.06));
  border: 1px dashed rgba(0,200,240,0.3); border-radius: 16px; display: flex; flex-direction: column;
  align-items: center; justify-content: center; color: var(--text-secondary); position: relative; overflow: hidden;
}
.hero-placeholder::before {
  content: ''; position: absolute; top: 50%; left: 50%; transform: translate(-50%,-50%);
  width: 200px; height: 200px; background: radial-gradient(circle, rgba(0,200,240,0.15), transparent);
  border-radius: 50%;
}
.placeholder-icon { font-size: 40px; margin-bottom: 10px; position: relative; z-index: 1; }
.placeholder-text { font-size: 13px; position: relative; z-index: 1; opacity: 0.7; }

/* ===== Features Grid ===== */
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.feature-card {
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius-card);
  padding: var(--card-padding); transition: all 0.3s; position: relative; overflow: hidden;
}
.feature-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 2px;
  background: var(--cta-gradient); opacity: 0; transition: opacity 0.3s;
}
.feature-card:hover { border-color: rgba(0,200,240,0.3); transform: translateY(-4px); box-shadow: 0 12px 40px rgba(0,0,0,0.3); }
.feature-card:hover::before { opacity: 1; }

.feature-img {
  width: 100%; aspect-ratio: 16/9; background: linear-gradient(135deg, rgba(0,200,240,0.08), rgba(0,128,255,0.05));
  border-radius: 8px; margin-bottom: 16px; border: 1px dashed rgba(0,200,240,0.2);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  font-size: 32px; color: var(--text-secondary);
}
.feature-img-label { font-size: 11px; margin-top: 6px; opacity: 0.6; }
.feature-card h3 { font-size: 16px; margin-bottom: 8px; }
.feature-card p { font-size: 14px; line-height: 1.65; }

/* ===== Pricing ===== */
.pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; align-items: start; }
.pricing-card {
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius-card);
  padding: 28px; position: relative; transition: all 0.3s;
}
.pricing-card.recommended {
  border-color: var(--cta-start); box-shadow: 0 0 0 1px rgba(0,200,240,0.25), var(--cta-glow); transform: translateY(-8px);
}
.pricing-badge {
  position: absolute; top: -12px; left: 50%; transform: translateX(-50%);
  background: var(--cta-gradient); color: #fff; font-size: 12px; font-weight: 600;
  padding: 4px 16px; border-radius: 20px; white-space: nowrap;
}
.pricing-name { font-size: 17px; font-weight: 600; margin-bottom: 12px; }
.pricing-price { font-size: 42px; font-weight: 700; line-height: 1; margin-bottom: 4px; }
.pricing-price .currency { font-size: 20px; font-weight: 500; }
.pricing-price .period { font-size: 15px; font-weight: 400; color: var(--text-secondary); }
.pricing-period-note { font-size: 12px; color: var(--text-secondary); margin-bottom: 20px; }
.pricing-divider { height: 1px; background: var(--border-color); margin: 16px 0; }
.pricing-feature-item {
  display: flex; align-items: center; gap: 8px; font-size: 14px; color: var(--text-secondary);
  padding: 5px 0;
}
.pricing-feature-item .check { color: var(--cta-start); font-weight: 700; flex-shrink: 0; }
.pricing-btn-wrap { margin-top: 20px; }

/* ===== FAQ ===== */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  border: 1px solid var(--border-color); border-radius: var(--radius-card);
  margin-bottom: 8px; overflow: hidden; transition: border-color 0.2s;
}
.faq-item.open { border-color: rgba(0,200,240,0.4); }
.faq-question {
  display: flex; align-items: center; justify-content: space-between; padding: 18px 20px;
  cursor: pointer; font-size: 15px; font-weight: 500; color: var(--text-primary);
  user-select: none; gap: 16px; background: transparent;
}
.faq-question:hover { background: rgba(255,255,255,0.02); }
.faq-icon {
  flex-shrink: 0; width: 22px; height: 22px; border: 1.5px solid var(--border-color);
  border-radius: 50%; display: flex; align-items: center; justify-content: center;
  font-size: 14px; transition: all 0.3s; color: var(--text-secondary); line-height: 1;
}
.faq-item.open .faq-icon {
  background: var(--cta-gradient); border-color: transparent; color: #fff; transform: rotate(45deg);
}
.faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.35s ease; }
.faq-answer-inner {
  padding: 16px 20px 18px; font-size: 14px; color: var(--text-secondary); line-height: 1.75;
  border-top: 1px solid var(--border-color);
}
.faq-item.open .faq-answer { max-height: 400px; }
.faq-more { text-align: center; margin-top: 32px; }

/* ===== Download Hero ===== */
.download-hero { padding: 60px 0 48px; }
.download-hero-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.download-hero-content h1 { font-size: 36px; margin-bottom: 24px; line-height: 1.25; }
.download-checklist { margin-bottom: 28px; }
.check-item {
  display: flex; align-items: flex-start; gap: 10px; font-size: 14px; color: var(--text-secondary);
  margin-bottom: 12px;
}
.check-circle {
  width: 20px; height: 20px; background: rgba(0,200,240,0.12); border-radius: 50%;
  display: flex; align-items: center; justify-content: center; color: var(--cta-start);
  font-size: 11px; font-weight: 700; flex-shrink: 0; margin-top: 1px;
}
.download-version { font-size: 12px; color: var(--text-secondary); margin-top: 10px; }

/* Platform Section */
.platform-section {
  padding: 56px 0; background: rgba(10,26,58,0.5);
  border-top: 1px solid var(--border-color); border-bottom: 1px solid var(--border-color);
}
.platform-tabs { display: flex; gap: 12px; margin-top: 32px; flex-wrap: wrap; justify-content: center; }
.platform-tab {
  display: flex; align-items: center; gap: 12px; padding: 14px 20px;
  background: var(--bg-card); border: 1.5px solid var(--border-color); border-radius: var(--radius-card);
  cursor: pointer; transition: all 0.2s; font-family: inherit; color: var(--text-secondary); font-size: 14px;
}
.platform-tab:hover { border-color: rgba(0,200,240,0.4); color: var(--text-primary); }
.platform-tab.active {
  border-color: var(--cta-start); color: var(--text-primary);
  background: rgba(0,200,240,0.08); box-shadow: 0 0 14px rgba(0,200,240,0.15);
}
.platform-tab .p-icon { font-size: 22px; }
.platform-tab-name { font-weight: 600; font-size: 14px; }
.platform-tab-version { font-size: 11px; color: var(--text-secondary); margin-top: 1px; }

/* Install Steps */
.install-section { padding: 60px 0; }
.install-steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin: 36px 0 40px; }
.install-step {
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius-card); padding: var(--card-padding); text-align: center;
}
.step-img {
  width: 100%; aspect-ratio: 16/10; background: linear-gradient(135deg, rgba(0,200,240,0.06), rgba(0,128,255,0.04));
  border-radius: 8px; margin-bottom: 16px; border: 1px dashed rgba(0,200,240,0.2);
  display: flex; align-items: center; justify-content: center; position: relative;
  flex-direction: column; font-size: 12px; color: var(--text-secondary);
}
.step-num {
  position: absolute; top: 10px; left: 10px; width: 26px; height: 26px;
  background: var(--cta-gradient); border-radius: 50%; display: flex; align-items: center;
  justify-content: center; font-size: 12px; font-weight: 700; color: #fff;
}
.install-step h3 { font-size: 15px; margin-bottom: 8px; }
.install-step p { font-size: 13px; }
.install-cta { text-align: center; }

/* Video */
.video-section { padding: 56px 0; border-top: 1px solid var(--border-color); background: rgba(10,26,58,0.3); }
.video-player {
  max-width: 720px; margin: 32px auto 0; aspect-ratio: 16/9; background: #000;
  border-radius: var(--radius-card); border: 1px solid var(--border-color);
  display: flex; align-items: center; justify-content: center; overflow: hidden;
}
.play-btn {
  width: 64px; height: 64px; background: var(--cta-gradient); border-radius: 50%;
  display: flex; align-items: center; justify-content: center; font-size: 22px;
  cursor: pointer; box-shadow: var(--cta-glow); transition: transform 0.2s;
}
.play-btn:hover { transform: scale(1.1); }

/* ===== Auth ===== */
.auth-page { min-height: 100vh; display: flex; flex-direction: column; }
.auth-main { flex: 1; display: flex; align-items: center; justify-content: center; padding: 48px 24px; }
.auth-card {
  background: var(--login-card-bg); border-radius: 16px; padding: 40px;
  width: 100%; max-width: 440px; box-shadow: 0 24px 80px rgba(0,0,0,0.5);
}
.auth-logo { text-align: center; margin-bottom: 28px; }
.auth-logo-icon {
  width: 64px; height: 64px; background: var(--cta-gradient); border-radius: 16px;
  display: flex; align-items: center; justify-content: center; font-size: 30px;
  margin: 0 auto 12px;
}
.auth-logo-name { font-size: 17px; font-weight: 700; color: #1A1A2E; }
.auth-title { font-size: 22px; font-weight: 700; color: #1A1A2E; text-align: center; margin-bottom: 24px; }
.form-group { margin-bottom: 14px; }
.form-input {
  width: 100%; padding: 12px 16px; font-size: 15px; font-family: inherit;
  background: #fff; border: 1.5px solid #D8DDE8; border-radius: var(--radius-btn);
  color: #1A1A2E; transition: border-color 0.2s, box-shadow 0.2s; outline: none;
}
.form-input::placeholder { color: #B0BAC9; }
.form-input:focus { border-color: var(--cta-start); box-shadow: 0 0 0 3px rgba(0,200,240,0.15); }
.form-input.error { border-color: #E84A5F; }
.form-error { font-size: 12px; color: #E84A5F; margin-top: 4px; display: none; }
.form-error.show { display: block; }
.auth-submit { margin-top: 20px; }
.auth-switch { text-align: center; margin-top: 16px; font-size: 14px; color: #8899BB; }
.auth-switch a { color: var(--cta-start); font-weight: 600; }
.auth-switch a:hover { text-decoration: underline; }

/* ===== Support ===== */
.support-hero { padding: 64px 0 48px; }
.support-hero h1 { font-size: 38px; margin-bottom: 16px; max-width: 680px; line-height: 1.25; }
.support-hero p { font-size: 16px; max-width: 540px; }
.support-channels { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin-top: 48px; }
.support-card {
  background: var(--bg-card); border: 1px solid var(--border-color); border-radius: var(--radius-card);
  padding: 28px 20px; text-align: center; transition: all 0.3s;
}
.support-card:hover { border-color: rgba(0,200,240,0.3); transform: translateY(-4px); }
.support-icon {
  width: 72px; height: 72px; background: linear-gradient(135deg, rgba(0,200,240,0.1), rgba(0,128,255,0.07));
  border-radius: 16px; display: flex; align-items: center; justify-content: center;
  font-size: 32px; margin: 0 auto 16px; border: 1px solid var(--border-color);
}
.support-card h3 { font-size: 16px; margin-bottom: 8px; }
.support-card p { font-size: 13px; margin-bottom: 20px; min-height: 44px; }

/* ===== Footer ===== */
.footer { background: rgba(0,0,0,0.25); border-top: 1px solid var(--border-color); padding: 48px 0 24px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 36px; }
.footer-brand .logo { margin-bottom: 12px; }
.footer-brand p { font-size: 13px; line-height: 1.7; max-width: 250px; }
.footer-socials { display: flex; gap: 8px; margin-top: 16px; }
.social-btn {
  width: 32px; height: 32px; background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: 6px; display: flex; align-items: center; justify-content: center;
  font-size: 14px; cursor: pointer; transition: all 0.2s; color: var(--text-secondary); text-decoration: none;
}
.social-btn:hover { border-color: rgba(0,200,240,0.4); color: var(--cta-start); }
.footer-col h4 { font-size: 13px; font-weight: 600; color: var(--text-primary); margin-bottom: 16px; text-transform: uppercase; letter-spacing: 0.5px; }
.footer-col ul li { margin-bottom: 10px; }
.footer-col ul li a { font-size: 13px; color: var(--text-secondary); transition: color 0.2s; }
.footer-col ul li a:hover { color: var(--cta-start); }
.footer-col ul li.disabled a { cursor: default; opacity: 0.4; pointer-events: none; }
.footer-bottom {
  border-top: 1px solid var(--border-color); padding-top: 20px;
  display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 12px;
}
.footer-copyright { font-size: 12px; color: var(--text-secondary); }

/* ===== Demo Bar ===== */
.demo-bar {
  position: fixed; bottom: 20px; right: 20px; z-index: 999;
  background: rgba(0,200,240,0.92); color: #030f26; padding: 9px 18px; border-radius: 24px;
  font-size: 13px; font-weight: 700; cursor: pointer; backdrop-filter: blur(8px);
  box-shadow: 0 4px 20px rgba(0,200,240,0.4); transition: all 0.2s; border: none; font-family: inherit;
}
.demo-bar:hover { transform: translateY(-2px); box-shadow: 0 8px 30px rgba(0,200,240,0.5); }

/* ===== Responsive ===== */
@media (max-width: 1199px) {
  h1 { font-size: 40px; }
  .hero-content h1 { font-size: 44px; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .support-channels { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 24px; }
}
@media (max-width: 768px) {
  h1 { font-size: 32px; }
  h2 { font-size: 26px; }
  .hero-content h1 { font-size: 34px; }
  .hero-subtitle { font-size: 26px; }
  .section { padding: 56px 0; }
  .nav { display: none; }
  .hamburger { display: flex; }
  .nav-right .lang-area { display: none; }
  .hero-inner,
  .download-hero-inner { grid-template-columns: 1fr; }
  .hero-visual { display: none; }
  .features-grid { grid-template-columns: 1fr; }
  .pricing-grid { grid-template-columns: 1fr; gap: 16px; }
  .pricing-card.recommended { transform: none; }
  .install-steps { grid-template-columns: 1fr; }
  .platform-tabs { flex-direction: column; }
  .support-channels { grid-template-columns: 1fr 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}
@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .support-channels { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero-badges { flex-direction: column; gap: 8px; }
}

/* ===== Pricing Page ===== */
.pricing-hero { padding: 64px 0 48px; }
.pricing-card.selectable { cursor: pointer; }
.pricing-card.selectable:hover { border-color: rgba(0,200,240,0.4); transform: translateY(-4px); }
.pricing-card.selected {
  border-color: var(--cta-start); box-shadow: 0 0 0 1px rgba(0,200,240,0.3), var(--cta-glow);
  transform: translateY(-8px);
}
.pricing-card.selectable.recommended { transform: translateY(-8px); }
.pricing-card.selectable.recommended.selected { transform: translateY(-12px); }

/* Compare Cards */
.compare-section { padding: 0 0 80px; }
.compare-note { font-size: 12px; color: var(--text-secondary); text-align: center; margin-top: 24px; }
.plan-compare-wrap { display: grid; grid-template-columns: 1fr auto 1fr; gap: 24px; align-items: start; margin-top: 40px; }
.compare-plan-card {
  background: var(--bg-card); border: 1px solid var(--border-color);
  border-radius: var(--radius-card); padding: 32px; transition: border-color 0.3s;
}
.compare-plan-card.is-upgrade { border-color: var(--cta-start); box-shadow: 0 0 0 1px rgba(0,200,240,0.2); }
.compare-card-name { font-size: 16px; font-weight: 600; margin-bottom: 6px; }
.compare-card-price { font-size: 34px; font-weight: 700; line-height: 1; margin-bottom: 4px; }
.compare-card-price .currency { font-size: 18px; font-weight: 500; }
.compare-card-price .period { font-size: 14px; font-weight: 400; color: var(--text-secondary); }
.compare-card-note { font-size: 12px; color: var(--text-secondary); margin-bottom: 24px; }
.compare-card-divider { height: 1px; background: var(--border-color); margin: 20px 0; }
.compare-card-highlights { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.compare-card-highlights li { display: flex; align-items: flex-start; gap: 10px; font-size: 14px; color: var(--text-secondary); line-height: 1.4; }
.compare-card-highlights li .ck { color: var(--cta-start); font-weight: 700; flex-shrink: 0; margin-top: 1px; }
.compare-vs {
  display: flex; align-items: center; justify-content: center;
  width: 44px; height: 44px; border-radius: 50%; background: var(--bg-card);
  border: 1px solid var(--border-color); font-size: 12px; font-weight: 700;
  color: var(--text-secondary); margin-top: 100px; flex-shrink: 0;
}
@media (max-width: 768px) {
  .plan-compare-wrap { grid-template-columns: 1fr; }
  .compare-vs { margin: 0 auto; width: 36px; height: 36px; }
}

/* ===== Payment Modal ===== */
.modal-overlay {
  position: fixed; inset: 0; background: rgba(2,11,42,0.75);
  display: flex; align-items: center; justify-content: center;
  z-index: 900; opacity: 0; visibility: hidden; transition: opacity 0.2s, visibility 0.2s;
  backdrop-filter: blur(4px);
}
.modal-overlay.open { opacity: 1; visibility: visible; }
.pay-modal {
  background: #fff; border-radius: 20px; padding: 36px 28px 28px;
  width: 360px; max-width: calc(100vw - 32px); position: relative;
  box-shadow: 0 24px 80px rgba(0,0,0,0.4);
}
.pay-modal-close {
  position: absolute; top: 14px; right: 14px;
  width: 28px; height: 28px; border-radius: 50%; border: none; cursor: pointer;
  background: #F0F2F5; color: #8A96A8; font-size: 14px;
  display: flex; align-items: center; justify-content: center; transition: background 0.15s;
}
.pay-modal-close:hover { background: #E2E6EC; color: #4A5568; }
.pay-modal-title {
  text-align: center; font-size: 15px; font-weight: 600; margin-bottom: 8px;
  background: var(--cta-gradient); -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.pay-modal-price {
  text-align: center; font-size: 38px; font-weight: 700; color: #0D1A2E;
  margin-bottom: 24px; letter-spacing: -1px;
}
.pay-modal-price .pay-currency { font-size: 22px; font-weight: 500; }
.pay-methods { display: flex; flex-direction: column; gap: 10px; margin-bottom: 20px; }
.pay-method {
  display: flex; align-items: center; gap: 12px;
  border: 1.5px solid #E2E8F0; border-radius: 12px; padding: 12px 14px;
  cursor: pointer; transition: border-color 0.15s, background 0.15s;
}
.pay-method:hover { border-color: #93C5FD; background: #F8FBFF; }
.pay-method.selected { border-color: #1677FF; background: #F0F7FF; }
.pay-method-name { font-size: 14px; color: #0D1A2E; font-weight: 500; }
.pay-icon {
  width: 38px; height: 38px; border-radius: 10px; flex-shrink: 0;
  display: flex; align-items: center; justify-content: center;
  font-size: 15px; font-weight: 800; color: #fff;
}
.pay-icon-wechat { background: #07C160; }
.pay-icon-alipay { background: #1677FF; font-size: 18px; }
.pay-icon-usdt { background: #26A17B; font-size: 13px; letter-spacing: -1px; }
.pay-radio {
  width: 20px; height: 20px; border-radius: 50%; border: 2px solid #D0D7E3;
  margin-left: auto; flex-shrink: 0; display: flex; align-items: center;
  justify-content: center; transition: all 0.15s;
}
.pay-method.selected .pay-radio { background: #1677FF; border-color: #1677FF; }
.pay-method.selected .pay-radio::after { content: '✓'; color: #fff; font-size: 11px; font-weight: 700; }
.pay-tips {
  background: #F8FAFC; border-radius: 10px; padding: 12px 14px;
  margin-bottom: 20px; color: #7A8AA0; font-size: 12px; line-height: 1.8;
}
.pay-tips p { margin: 0; }
.pay-tips p:first-child { font-weight: 500; color: #5A6A7E; margin-bottom: 2px; }
.pay-confirm-btn {
  width: 100%; padding: 14px; border-radius: 12px; border: none; cursor: pointer;
  background: var(--cta-gradient); color: #fff; font-size: 16px; font-weight: 600;
  font-family: inherit; transition: opacity 0.2s, transform 0.15s;
}
.pay-confirm-btn:hover { opacity: 0.92; transform: translateY(-1px); }
.pay-confirm-btn:active { transform: translateY(0); }

/* ===== Breadcrumb ===== */
.breadcrumb {
  display: flex; align-items: center; gap: 6px; padding: 18px 0 0;
  font-size: 13px; color: var(--text-secondary);
}
.breadcrumb a { color: var(--text-secondary); transition: color 0.2s; }
.breadcrumb a:hover { color: var(--cta-start); }
.breadcrumb .sep { opacity: 0.45; font-size: 11px; }
.breadcrumb .current { color: var(--text-primary); }

/* ===== Account trigger (logged-in header state) ===== */
.nav-my-account {
  font-size: 14px; font-weight: 500; color: var(--text-secondary);
  padding: 6px 8px; border-radius: 6px; transition: color 0.2s;
}
.nav-my-account:hover { color: var(--text-primary); }

.account-trigger {
  display: flex; align-items: center; gap: 6px; padding: 5px 12px 5px 6px;
  background: rgba(255,255,255,0.05); border: 1px solid var(--border-color);
  border-radius: 20px; cursor: pointer; font-family: inherit; font-size: 13px;
  color: var(--text-primary); transition: all 0.2s;
}
.account-trigger:hover { border-color: rgba(0,200,240,0.4); background: rgba(0,200,240,0.06); }
.account-avatar-icon {
  width: 24px; height: 24px; background: var(--cta-gradient); border-radius: 50%;
  display: flex; align-items: center; justify-content: center; font-size: 12px; flex-shrink: 0;
}
.account-email { font-size: 13px; max-width: 130px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.account-arrow { font-size: 10px; color: var(--text-secondary); }

/* ===== Doc pages (privacy / terms / about) ===== */
.doc-page { padding: 40px 0 80px; }
.doc-page .container { max-width: 800px; }
.doc-page h1 { font-size: 32px; margin-bottom: 8px; }
.doc-update { font-size: 13px; color: var(--text-secondary); padding-bottom: 24px; margin-bottom: 32px; border-bottom: 1px solid var(--border-color); }
.doc-section { margin-bottom: 32px; }
.doc-section h2 { font-size: 17px; font-weight: 600; margin-bottom: 12px; color: var(--text-primary); }
.doc-section p { font-size: 15px; line-height: 1.85; margin-bottom: 10px; }
.doc-section ul { padding-left: 20px; margin-bottom: 10px; list-style: disc; }
.doc-section ul li { font-size: 15px; color: var(--text-secondary); line-height: 1.85; margin-bottom: 4px; }

/* About page */
.about-content { padding: 40px 0 80px; max-width: 760px; }
.about-content p { font-size: 16px; line-height: 1.9; margin-bottom: 12px; }
.about-list { margin: 8px 0 20px; }
.about-list li { font-size: 16px; color: var(--text-secondary); line-height: 1.9; padding-left: 16px; position: relative; }
.about-list li::before { content: '·'; position: absolute; left: 0; color: var(--cta-start); }
.about-contacts { margin-top: 32px; padding-top: 24px; border-top: 1px solid var(--border-color); }
.about-contacts p { margin-bottom: 8px; }
.about-contacts strong { color: var(--text-primary); margin-right: 8px; }

/* Feedback page */
.feedback-card { background: var(--login-card-bg); border-radius: 16px; padding: 40px; width: 100%; max-width: 640px; box-shadow: 0 24px 80px rgba(0,0,0,0.5); }
.feedback-title { font-size: 20px; font-weight: 700; color: #1A1A2E; text-align: center; margin-bottom: 24px; }
.feedback-textarea {
  width: 100%; padding: 14px 16px; font-size: 15px; font-family: inherit;
  background: #fff; border: 1.5px solid #D8DDE8; border-radius: var(--radius-btn);
  color: #1A1A2E; outline: none; resize: vertical; min-height: 240px; line-height: 1.6;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.feedback-textarea::placeholder { color: #B0BAC9; }
.feedback-textarea:focus { border-color: var(--cta-start); box-shadow: 0 0 0 3px rgba(0,200,240,0.15); }
.upload-area { margin-top: 12px; }
.upload-btn {
  width: 64px; height: 64px; border: 2px dashed #D8DDE8; border-radius: var(--radius-btn);
  background: #fff; display: flex; align-items: center; justify-content: center;
  font-size: 22px; color: #B0BAC9; cursor: pointer; transition: all 0.2s;
}
.upload-btn:hover { border-color: var(--cta-start); color: var(--cta-start); }
.upload-hint { font-size: 12px; color: #B0BAC9; margin-top: 6px; }
.feedback-submit { margin-top: 24px; }
.feedback-success { display: none; text-align: center; padding: 16px 0 8px; }
.feedback-success .s-icon { font-size: 44px; margin-bottom: 12px; }
.feedback-success h3 { color: #1A1A2E; margin-bottom: 8px; }
.feedback-success p { color: #8899BB; font-size: 14px; }