/* ==========================================================================
   SteadyAI 极简高转化广告落地页样式 (Mobile-First 架构)
   适配设备: 智能手机 (优先) / 平板 / 电脑端居中
   ========================================================================== */

:root {
  --bg-body: #07090e;
  --bg-card: #0f172a;
  --bg-card-sub: #172033;
  --bg-glass: rgba(15, 23, 42, 0.85);

  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-highlight: rgba(255, 255, 255, 0.16);

  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;

  --accent-blue: #0ea5e9;
  --accent-cyan: #38bdf8;
  --accent-chatgpt: #10b981;
  --accent-gemini: #8b5cf6;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.5);
  --shadow-glow-chatgpt: 0 0 28px rgba(16, 185, 129, 0.2);
  --shadow-glow-gemini: 0 0 28px rgba(139, 92, 246, 0.25);
}

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

html {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color-scheme: dark;
  background-color: var(--bg-body);
  color: var(--text-main);
  line-height: 1.5;
  scroll-behavior: smooth;
  scrollbar-gutter: stable;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100dvh;
  position: relative;
  background: 
    radial-gradient(circle at 10% 10%, rgba(16, 185, 129, 0.06) 0%, transparent 40%),
    radial-gradient(circle at 90% 15%, rgba(139, 92, 246, 0.07) 0%, transparent 45%),
    var(--bg-body);
  padding-block-end: 76px; /* 留出手机端吸底条空间 */
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
  font-size: inherit;
}

/* 页面通用居中容器 */
.site-container {
  inline-size: 100%;
  max-inline-size: 860px; /* 电脑端舒适居中阅读宽度 */
  margin-inline: auto;
  padding-inline: 1.15rem;
}

/* ==========================================================================
   Header 极简顶部条
   ========================================================================== */

.simple-header {
  position: sticky;
  inset-block-start: 0;
  z-index: 50;
  background: rgba(7, 9, 14, 0.88);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-block-end: 1px solid var(--border-subtle);
  block-size: 58px;
  display: flex;
  align-items: center;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-box {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.brand-icon {
  inline-size: 26px;
  block-size: 26px;
  filter: drop-shadow(0 0 8px rgba(14, 165, 233, 0.5));
}

.brand-title {
  font-size: 1rem;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: #fff;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.btn-text {
  font-size: 0.88rem;
  color: var(--text-muted);
  font-weight: 500;
}

.btn-text:hover {
  color: #fff;
}

.btn-header-reg {
  font-size: 0.84rem;
  font-weight: 700;
  background: rgba(14, 165, 233, 0.15);
  border: 1px solid rgba(14, 165, 233, 0.35);
  color: var(--accent-cyan);
  padding: 0.35rem 0.85rem;
  border-radius: var(--radius-full);
}

/* ==========================================================================
   Hero 首屏焦点区
   ========================================================================== */

.hero-box {
  text-align: center;
  padding-block-start: clamp(1.75rem, 5vw, 3rem);
  padding-block-end: clamp(1.5rem, 4vw, 2.5rem);
}

.trust-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.25rem 0.85rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  color: var(--accent-cyan);
  margin-block-end: 1rem;
}

.dot-live {
  inline-size: 7px;
  block-size: 7px;
  border-radius: 50%;
  background: var(--accent-chatgpt);
  box-shadow: 0 0 8px var(--accent-chatgpt);
}

.main-title {
  font-size: clamp(1.85rem, 6vw, 2.65rem);
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin-block-end: 0.85rem;
}

.title-highlight {
  background: linear-gradient(135deg, #38bdf8 0%, #34d399 50%, #c084fc 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.main-subtitle {
  font-size: clamp(0.95rem, 2.8vw, 1.1rem);
  color: var(--text-muted);
  line-height: 1.6;
  max-inline-size: 620px;
  margin-inline: auto;
  margin-block-end: 1.75rem;
}

.quick-cta-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.85rem;
  flex-wrap: wrap;
}

.btn-main-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.6rem;
  background: linear-gradient(135deg, #0ea5e9, #2563eb);
  color: #fff;
  font-size: 0.95rem;
  font-weight: 700;
  border-radius: var(--radius-full);
  box-shadow: 0 4px 18px rgba(14, 165, 233, 0.4);
}

.btn-main-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.4rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-highlight);
  color: var(--text-main);
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-full);
}

/* ==========================================================================
   三大特点极简卡片
   ========================================================================== */

.features-section {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.85rem;
  margin-block-end: clamp(2rem, 5vw, 3rem);
}

@media (min-width: 680px) {
  .features-section {
    grid-template-columns: repeat(3, 1fr);
  }
}

.feature-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.15rem 1.1rem;
  display: flex;
  align-items: flex-start;
  gap: 0.85rem;
}

.feature-icon {
  inline-size: 40px;
  block-size: 40px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.icon-speed {
  background: rgba(14, 165, 233, 0.12);
  color: var(--accent-cyan);
}

.icon-shield {
  background: rgba(16, 185, 129, 0.12);
  color: var(--accent-chatgpt);
}

.icon-safe {
  background: rgba(139, 92, 246, 0.12);
  color: var(--accent-gemini);
}

.feature-title {
  font-size: 0.96rem;
  font-weight: 700;
  margin-block-end: 0.25rem;
  color: #fff;
}

.feature-desc {
  font-size: 0.84rem;
  color: var(--text-muted);
  line-height: 1.45;
}

/* ==========================================================================
   套餐定价区 (ChatGPT ¥38/月, Gemini ¥8/月)
   ========================================================================== */

.plans-section {
  margin-block-end: clamp(2.5rem, 6vw, 3.5rem);
}

.section-heading {
  text-align: center;
  margin-block-end: 1.5rem;
}

.heading-text {
  font-size: clamp(1.4rem, 4vw, 1.85rem);
  font-weight: 800;
  margin-block-end: 0.35rem;
}

.heading-sub {
  font-size: 0.88rem;
  color: var(--text-muted);
}

.plans-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}

@media (min-width: 680px) {
  .plans-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.plan-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.65rem 1.45rem;
  display: flex;
  flex-direction: column;
  position: relative;
  box-shadow: var(--shadow-sm);
}

.plan-chatgpt {
  border-top: 3px solid var(--accent-chatgpt);
}

.plan-gemini {
  border-top: 3px solid var(--accent-gemini);
}

.plan-badge {
  position: absolute;
  inset-block-start: 12px;
  inset-inline-end: 14px;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 0.15rem 0.55rem;
  border-radius: var(--radius-full);
  background: rgba(16, 185, 129, 0.15);
  color: #34d399;
  border: 1px solid rgba(16, 185, 129, 0.3);
}

.gemini-badge {
  background: rgba(139, 92, 246, 0.15);
  color: #c084fc;
  border-color: rgba(139, 92, 246, 0.3);
}

.plan-header {
  margin-block-end: 1rem;
}

.plan-title {
  font-size: 1.35rem;
  font-weight: 800;
  margin-block-end: 0.25rem;
  color: #fff;
}

.plan-desc {
  font-size: 0.84rem;
  color: var(--text-muted);
}

.price-wrap {
  display: flex;
  align-items: baseline;
  gap: 0.25rem;
  padding-block: 0.75rem;
  margin-block-end: 1.2rem;
  border-block: 1px solid var(--border-subtle);
}

.price-symbol {
  font-size: 1.35rem;
  font-weight: 700;
  color: #fff;
}

.price-val {
  font-size: 3.2rem;
  font-weight: 900;
  line-height: 1;
  color: #fff;
  letter-spacing: -0.03em;
}

.plan-chatgpt .price-val {
  color: #34d399;
}

.plan-gemini .price-val {
  color: #c084fc;
}

.price-unit {
  font-size: 0.88rem;
  color: var(--text-dim);
}

.plan-points {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  font-size: 0.88rem;
  color: #e2e8f0;
  margin-block-end: 1.6rem;
  flex-grow: 1;
}

.plan-btns {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.btn-card-primary {
  inline-size: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, #10b981, #059669);
  color: #fff;
  font-size: 0.94rem;
  font-weight: 700;
  box-shadow: 0 4px 14px rgba(16, 185, 129, 0.35);
}

.btn-gemini-primary {
  background: linear-gradient(135deg, #8b5cf6, #6366f1);
  box-shadow: 0 4px 14px rgba(139, 92, 246, 0.35);
}

.btn-card-sub {
  inline-size: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  font-size: 0.86rem;
  font-weight: 600;
}

.btn-card-sub:hover {
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
}

/* ==========================================================================
   核心转化区：微信二维码 + 自助注册
   ========================================================================== */

.action-section {
  margin-block-end: 3rem;
}

.action-box {
  background: var(--bg-card);
  border: 1px solid var(--border-highlight);
  border-radius: var(--radius-xl);
  padding: clamp(1.4rem, 4vw, 2.2rem) clamp(1.1rem, 3.5vw, 1.8rem);
  box-shadow: var(--shadow-lg);
}

.action-box-title {
  font-size: clamp(1.3rem, 3.5vw, 1.65rem);
  font-weight: 800;
  text-align: center;
  margin-block-end: 0.35rem;
}

.action-box-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  text-align: center;
  margin-block-end: 1.8rem;
}

.contact-methods-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}

@media (min-width: 680px) {
  .contact-methods-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.method-card {
  background: var(--bg-card-sub);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.35rem 1.2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.method-tag {
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--accent-cyan);
  background: rgba(14, 165, 233, 0.12);
  padding: 0.15rem 0.55rem;
  border-radius: var(--radius-xs);
  margin-block-end: 0.65rem;
}

.tag-self {
  color: #34d399;
  background: rgba(16, 185, 129, 0.12);
}

.method-title {
  font-size: 1.15rem;
  font-weight: 800;
  margin-block-end: 0.35rem;
}

.method-tip {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-block-end: 1.15rem;
  line-height: 1.45;
}

/* 微信二维码样式 */
.qr-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  margin-block-end: 1rem;
}

.qr-card {
  background: #ffffff;
  padding: 8px;
  border-radius: var(--radius-sm);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
  inline-size: 176px;
  block-size: 176px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.qr-img {
  inline-size: 100%;
  block-size: 100%;
  object-fit: contain;
  border-radius: 4px;
}

.qr-svg {
  inline-size: 100%;
  block-size: 100%;
}

.qr-label {
  font-size: 0.75rem;
  color: var(--text-dim);
}

.wechat-row {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(255, 255, 255, 0.05);
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-subtle);
  font-size: 0.86rem;
  flex-wrap: wrap;
  justify-content: center;
}

.wechat-id-text strong {
  font-family: ui-monospace, monospace;
  color: var(--accent-cyan);
}

.btn-copy {
  background: rgba(14, 165, 233, 0.2);
  color: var(--accent-cyan);
  border: 1px solid rgba(14, 165, 233, 0.4);
  font-size: 0.78rem;
  font-weight: 700;
  padding: 0.2rem 0.55rem;
  border-radius: var(--radius-xs);
  transition: all 0.2s ease;
}

.btn-copy:hover {
  background: rgba(14, 165, 233, 0.35);
}

/* 自助注册卡片内部 */
.self-serve-body {
  inline-size: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  flex-grow: 1;
  justify-content: space-between;
}

.self-features {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  inline-size: 100%;
  text-align: left;
  background: rgba(0, 0, 0, 0.25);
  padding: 1rem 1.15rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  margin-block-end: 1.5rem;
  font-size: 0.86rem;
  color: #cbd5e1;
}

.btn-register-direct {
  inline-size: 100%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  background: linear-gradient(135deg, #0ea5e9, #2563eb);
  color: #fff;
  padding: 0.85rem 1.25rem;
  border-radius: var(--radius-full);
  font-size: 0.95rem;
  font-weight: 700;
  box-shadow: 0 4px 18px rgba(14, 165, 233, 0.4);
  transition: transform 0.2s ease;
}

.btn-register-direct:hover {
  transform: translateY(-2px);
  filter: brightness(1.1);
}

.reg-tip {
  font-size: 0.74rem;
  color: var(--text-dim);
  margin-block-start: 0.85rem;
}

/* ==========================================================================
   极简页脚
   ========================================================================== */

.simple-footer {
  border-block-start: 1px solid var(--border-subtle);
  padding-block: 1.75rem;
  font-size: 0.78rem;
  color: var(--text-dim);
  text-align: center;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.disclaimer-text {
  font-size: 0.72rem;
  color: #475569;
}

/* ==========================================================================
   手机端吸底条 (适配手机屏幕，电脑端隐藏)
   ========================================================================== */

.mobile-bottom-bar {
  display: none;
  position: fixed;
  inset-block-end: 0;
  inset-inline: 0;
  z-index: 99;
  background: rgba(13, 18, 29, 0.95);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-block-start: 1px solid var(--border-highlight);
  padding: 0.6rem 0.85rem calc(0.6rem + env(safe-area-inset-bottom));
  box-shadow: 0 -4px 16px rgba(0, 0, 0, 0.5);
  align-items: center;
  justify-content: space-between;
  gap: 0.65rem;
}

.m-price-info {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.m-label {
  font-size: 0.84rem;
  font-weight: 800;
  color: #fff;
}

.m-status {
  font-size: 0.68rem;
  color: var(--accent-chatgpt);
}

.m-btn-group {
  display: flex;
  gap: 0.45rem;
}

.m-btn {
  padding: 0.48rem 0.85rem;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 700;
  white-space: nowrap;
}

.m-btn-wx {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid var(--border-subtle);
  color: #fff;
}

.m-btn-reg {
  background: linear-gradient(135deg, #0ea5e9, #2563eb);
  color: #fff;
  box-shadow: 0 2px 8px rgba(14, 165, 233, 0.4);
}

@media (max-width: 680px) {
  .mobile-bottom-bar {
    display: flex;
  }
}

/* ==========================================================================
   复制成功提示 Toast
   ========================================================================== */

.toast-notice {
  position: fixed;
  inset-block-start: 20px;
  inset-inline-start: 50%;
  transform: translateX(-50%) translateY(-30px);
  z-index: 1000;
  background: #10b981;
  color: #fff;
  font-size: 0.84rem;
  font-weight: 700;
  padding: 0.55rem 1.15rem;
  border-radius: var(--radius-full);
  box-shadow: 0 4px 14px rgba(16, 185, 129, 0.4);
  opacity: 0;
  pointer-events: none;
  transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.toast-notice.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}