/* Binance AI Trader — marketing landing (static, themes) */

html {
  scroll-behavior: smooth;
}

html[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0c0d10;
  --bg-elevated: #12141a;
  --border: rgba(148, 163, 184, 0.12);
  --text: #e2e8f0;
  --text-muted: #94a3b8;
  --accent: #7dd3fc;
  --accent-dim: rgba(125, 211, 252, 0.15);
  --header-bg: rgba(12, 13, 16, 0.85);
  --btn-primary-border: rgba(125, 211, 252, 0.35);
  --demo-tag-border: rgba(125, 211, 252, 0.25);
  --meta-color: #64748b;
}

html[data-theme="light"] {
  color-scheme: light;
  --bg: #f8fafc;
  --bg-elevated: #ffffff;
  --border: rgba(15, 23, 42, 0.1);
  --text: #0f172a;
  --text-muted: #64748b;
  --accent: #0284c7;
  --accent-dim: rgba(2, 132, 199, 0.12);
  --header-bg: rgba(248, 250, 252, 0.92);
  --btn-primary-border: rgba(2, 132, 199, 0.35);
  --demo-tag-border: rgba(2, 132, 199, 0.28);
  --meta-color: #94a3b8;
}

:root {
  --radius: 10px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial,
    sans-serif;
  --maxw: 1080px;
  --icon-stroke: 1.75;
}

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

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

/* Icons (inline SVG) */
.icon {
  display: block;
  width: 1.35rem;
  height: 1.35rem;
  flex-shrink: 0;
  color: var(--accent);
}

.icon--lg {
  width: 1.75rem;
  height: 1.75rem;
}

.icon--muted {
  color: var(--text-muted);
}

.icon-stroke {
  fill: none;
  stroke: currentColor;
  stroke-width: var(--icon-stroke);
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--header-bg);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.site-header .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 56px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 1rem;
  letter-spacing: -0.02em;
  color: var(--text);
}

.brand__logo {
  width: 28px;
  height: 28px;
  color: var(--accent);
}

.brand:hover {
  text-decoration: none;
  color: var(--accent);
}

.nav {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav a:not(.btn) {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.nav a:not(.btn):hover {
  color: var(--text);
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 20px;
}

#theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: transparent;
  color: var(--text);
  cursor: pointer;
  position: relative;
}

#theme-toggle:hover {
  background: var(--bg-elevated);
}

#theme-toggle .theme-toggle__svg {
  display: block;
  width: 1.25rem;
  height: 1.25rem;
  color: var(--text-muted);
}

#theme-toggle:hover .theme-toggle__svg {
  color: var(--text);
}

/* 若未来恢复双 SVG：避免 .icon 的 display 盖掉 [hidden] */
#theme-toggle svg[hidden] {
  display: none !important;
}

#theme-toggle .icon {
  width: 1.25rem;
  height: 1.25rem;
  color: var(--text-muted);
}

#theme-toggle:hover .icon {
  color: var(--text);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 0.875rem;
  font-weight: 500;
  border: 1px solid var(--border);
  color: var(--text);
  background: transparent;
  cursor: pointer;
  text-decoration: none;
}

.btn:hover {
  background: var(--bg-elevated);
  text-decoration: none;
}

.btn-primary {
  background: var(--accent-dim);
  border-color: var(--btn-primary-border);
  color: var(--accent);
}

.btn-primary:hover {
  filter: brightness(1.05);
}

/* Hero */
.hero {
  padding: 72px 0 56px;
  /*border-bottom: 1px solid var(--border);*/
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
}

@media (max-width: 840px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }
}

.hero-copy h1 {
  margin: 0 0 16px;
  font-size: clamp(1.75rem, 4vw, 2.25rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.2;
  max-width: 22ch;
}

.hero-lede {
  margin: 0 0 12px;
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 42ch;
}

.hero-note {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-muted);
  max-width: 48ch;
}

.hero-figure {
  margin: 0;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
}

.hero-figure img {
  width: 100%;
  height: auto;
  display: block;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  padding: 6px 12px;
  font-size: 0.8rem;
  color: var(--text-muted);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 999px;
}

.hero__badge .icon {
  width: 1.1rem;
  height: 1.1rem;
}

.section {
  padding: 56px 0;
}

.section-head {
  margin-bottom: 28px;
}

.section-head h2 {
  margin: 0 0 8px;
  font-size: 1.35rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.section-head p {
  margin: 0;
  font-size: 0.95rem;
  color: var(--text-muted);
}

.section-footnote {
  margin: 24px 0 0;
  padding: 16px 18px;
  font-size: 0.9rem;
  color: var(--text-muted);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  line-height: 1.55;
}

.section-footnote strong {
  color: var(--text);
}

.why-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.pain-card {
  padding: 20px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.pain-card__icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
  background: var(--accent-dim);
  border-radius: 10px;
  color: var(--accent);
}

.pain-card__icon .icon {
  width: 1.35rem;
  height: 1.35rem;
  color: inherit;
}

.pain-card h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.35;
}

.pain-card p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.55;
}

.pain-card code {
  font-size: 0.8rem;
  padding: 1px 6px;
  border-radius: 4px;
  background: var(--accent-dim);
  color: var(--accent);
}

.stack-columns {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 28px 40px;
}

.stack-list {
  margin: 0;
  padding: 0 0 0 1.1rem;
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.65;
}

.stack-list li {
  margin-bottom: 12px;
}

.stack-list li:last-child {
  margin-bottom: 0;
}

.stack-list strong {
  color: var(--text);
  margin-right: 6px;
}

html[data-theme="light"] .pain-card {
  background: #f1f5f9;
}

/* Cards + media */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.card {
  padding: 20px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.card-media-wrap {
  padding: 0;
  overflow: hidden;
}

.card-media-wrap .card-media {
  width: 100%;
  height: 152px;
  object-fit: cover;
  display: block;
}

.card-media-wrap .card-body {
  padding: 18px 20px 20px;
}

.card-title-row {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-bottom: 8px;
}

.card-title-row .icon {
  margin-top: 2px;
}

.card-media-wrap h3 {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
  flex: 1;
}

.card-media-wrap p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.55;
}

/* Demo + KPI */
.demo-tag {
  display: inline-block;
  margin-bottom: 12px;
  padding: 4px 10px;
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-dim);
  border: 1px solid var(--demo-tag-border);
  border-radius: 6px;
}

.demo-disclaimer {
  margin: 0 0 20px;
  font-size: 0.85rem;
  color: var(--text-muted);
  max-width: 65ch;
}

.section-figure {
  margin: 0 0 24px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  background: var(--bg-elevated);
}

.section-figure img {
  width: 100%;
  height: auto;
  display: block;
  max-height: 280px;
  object-fit: cover;
}

.section-figure figcaption {
  padding: 10px 14px;
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.section-figure figcaption code {
  font-size: 0.7rem;
  color: var(--accent);
}

.section-visual-tail {
  padding-top: 0;
}

.section-figure--wide img {
  max-height: 220px;
}

.kpi-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
  margin-bottom: 32px;
}

.kpi {
  position: relative;
  padding: 20px;
  padding-top: 48px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.kpi__icon {
  position: absolute;
  top: 16px;
  left: 20px;
  width: 26px;
  height: 26px;
  color: var(--accent);
  opacity: 0.9;
}

.kpi .label {
  display: block;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.kpi .value {
  font-size: 1.65rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text);
}

.kpi .hint {
  display: block;
  margin-top: 4px;
  font-size: 0.75rem;
  color: var(--text-muted);
}

.monthly h3 {
  margin: 0 0 16px;
  font-size: 1rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 8px;
}

.monthly h3 .icon {
  width: 1.15rem;
  height: 1.15rem;
}

.demo-chart {
  margin: 0 0 12px;
  padding: 8px 4px 0;
  overflow-x: auto;
}

.demo-chart__svg {
  display: block;
  max-width: 100%;
}

.demo-chart__grid {
  stroke: var(--border);
  stroke-width: 1;
}

.demo-chart__area {
  fill: var(--accent);
  opacity: 0.14;
}

.demo-chart__line {
  stroke: var(--accent);
}

.demo-chart__dot {
  fill: var(--accent);
}

.demo-chart__ylabel,
.demo-chart__xlabel {
  fill: var(--text-muted);
  font-size: 11px;
  font-family: var(--font);
}

.demo-chart__val {
  fill: var(--text);
  font-size: 11px;
  font-weight: 600;
  font-family: var(--font);
}

.demo-chart__caption {
  margin: 0;
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* Steps */
.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 20px;
}

.step {
  display: flex;
  gap: 14px;
  padding: 20px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.step__icon-wrap {
  flex-shrink: 0;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-dim);
  border-radius: 10px;
  color: var(--accent);
}

.step__icon-wrap .icon {
  width: 1.4rem;
  height: 1.4rem;
  color: inherit;
}

.step h3 {
  margin: 0 0 6px;
  font-size: 0.95rem;
  font-weight: 600;
}

.step p {
  margin: 0;
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* Footer */
.site-footer {
  padding: 40px 0 32px;
  border-top: 1px solid var(--border);
  margin-top: 8px;
}

.site-footer p {
  margin: 0 0 12px;
  font-size: 0.8rem;
  color: var(--text-muted);
  max-width: 72ch;
  line-height: 1.65;
}

.site-footer .meta {
  margin-top: 20px;
  font-size: 0.75rem;
  color: var(--meta-color);
}

@media (max-width: 640px) {
  .nav__links {
    display: none;
  }

  .hero {
    padding-top: 48px;
  }
}