/* AlphaX — modern SaaS (Linear / Vercel / Stripe inspired) */
:root {
  --bg: #f7f7f5;
  --bg-muted: #f0efeb;
  --surface: #ffffff;
  --text: #171717;
  --text-secondary: #525252;
  --text-muted: #737373;
  --border: #e5e5e0;
  --border-strong: #d4d4d0;
  --accent: #4338ca;
  --accent-hover: #3730a3;
  --accent-soft: #eef2ff;
  --accent-ink: #312e81;
  --indigo-deep: #1e1b4b;
  --live: #059669;
  --live-bg: #ecfdf5;
  --shadow-sm: 0 1px 2px rgba(23, 23, 23, 0.04);
  --shadow-md: 0 4px 16px rgba(23, 23, 23, 0.06), 0 1px 3px rgba(23, 23, 23, 0.04);
  --shadow-lg: 0 12px 40px rgba(23, 23, 23, 0.08), 0 2px 8px rgba(23, 23, 23, 0.04);
  --radius: 14px;
  --radius-sm: 10px;
  --radius-full: 999px;
  --nav-h: 64px;
  --container: 1080px;
  --font: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; background: none; border: none; padding: 0; }
strong { font-weight: 600; }

.container {
  width: min(100% - 40px, var(--container));
  margin-inline: auto;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 44px;
  padding: 0 20px;
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 560;
  letter-spacing: -0.01em;
  transition: background 0.2s var(--ease), color 0.2s var(--ease), box-shadow 0.2s var(--ease), border-color 0.2s var(--ease), transform 0.2s var(--ease);
  white-space: nowrap;
}

.btn--sm { height: 36px; padding: 0 14px; font-size: 13px; }

.btn--primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 1px 2px rgba(67, 56, 202, 0.25);
}
.btn--primary:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(67, 56, 202, 0.28);
}

.btn--secondary {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}
.btn--secondary:hover {
  border-color: var(--border-strong);
  background: #fafaf9;
  transform: translateY(-1px);
}

.btn--on-dark {
  background: #fff;
  color: var(--indigo-deep);
  box-shadow: var(--shadow-sm);
}
.btn--on-dark:hover {
  background: #f5f5ff;
  transform: translateY(-1px);
}

.btn--ghost-on-dark {
  background: transparent;
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.28);
}
.btn--ghost-on-dark:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.45);
}

/* Nav */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--nav-h);
  background: rgba(247, 247, 245, 0.78);
  backdrop-filter: saturate(160%) blur(12px);
  -webkit-backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.nav.is-scrolled {
  border-bottom-color: var(--border);
  background: rgba(247, 247, 245, 0.92);
  box-shadow: var(--shadow-sm);
}

.nav__inner {
  height: var(--nav-h);
  display: flex;
  align-items: center;
  gap: 24px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.logo__mark {
  width: 28px;
  height: 28px;
}

.logo__text {
  font-size: 15px;
  font-weight: 650;
  letter-spacing: -0.03em;
  color: var(--text);
}

.nav__links {
  display: none;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}

.nav__links a {
  padding: 8px 12px;
  border-radius: 8px;
  font-size: 13.5px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.15s var(--ease), background 0.15s var(--ease);
}

.nav__links a:hover {
  color: var(--text);
  background: rgba(23, 23, 23, 0.04);
}

.nav__cta { display: none; margin-left: 8px; }

.nav__toggle {
  margin-left: auto;
  width: 40px;
  height: 40px;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  border-radius: 10px;
}

.nav__toggle span {
  display: block;
  width: 18px;
  height: 1.5px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.2s var(--ease), opacity 0.2s var(--ease);
}

.nav--open .nav__toggle span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
.nav--open .nav__toggle span:nth-child(2) { opacity: 0; }
.nav--open .nav__toggle span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

.nav__mobile {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 8px 0 20px;
  border-bottom: 1px solid var(--border);
  background: var(--bg);
}

.nav__mobile[hidden] { display: none !important; }

.nav__mobile a {
  padding: 12px 4px;
  font-size: 15px;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: 8px;
}

.nav__mobile a:hover { color: var(--text); }

@media (min-width: 900px) {
  .nav__links { display: flex; }
  .nav__cta { display: inline-flex; }
  .nav__toggle { display: none; }
  .nav__mobile { display: none !important; }
}

/* Hero */
.hero {
  padding: 56px 0 72px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: -20% 10% auto;
  height: 420px;
  background:
    radial-gradient(ellipse 60% 50% at 70% 20%, rgba(99, 102, 241, 0.12), transparent 70%),
    radial-gradient(ellipse 50% 40% at 20% 40%, rgba(165, 180, 252, 0.18), transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.hero__grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 40px;
  align-items: center;
}

@media (min-width: 900px) {
  .hero { padding: 80px 0 96px; }
  .hero__grid { grid-template-columns: 1.15fr 0.85fr; gap: 56px; }
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 20px;
  padding: 6px 12px 6px 10px;
  border-radius: var(--radius-full);
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
}

.eyebrow__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.hero__title {
  margin: 0 0 20px;
  font-size: clamp(2.25rem, 5vw, 3.5rem);
  font-weight: 680;
  letter-spacing: -0.045em;
  line-height: 1.12;
  color: var(--text);
}

.hero__lead {
  margin: 0 0 32px;
  max-width: 34em;
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--text-secondary);
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.hero__card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 24px;
  box-shadow: var(--shadow-lg);
}

.hero__card-label {
  margin: 0 0 16px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.hero__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.hero__list li {
  display: flex;
  gap: 14px;
  align-items: flex-start;
  padding: 14px 12px;
  border-radius: 12px;
  transition: background 0.15s var(--ease);
}

.hero__list li:hover { background: var(--bg-muted); }

.hero__list-num {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 11px;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.hero__list strong {
  display: block;
  font-size: 14.5px;
  letter-spacing: -0.02em;
  margin-bottom: 2px;
}

.hero__list span {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.4;
}

.hero__card-note {
  margin: 16px 0 0;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.5;
}

/* Sections */
.section {
  padding: 80px 0;
}

.section--muted {
  background: var(--bg-muted);
  border-block: 1px solid var(--border);
}

.section__head {
  max-width: 40rem;
  margin-bottom: 40px;
}

.section__label {
  margin: 0 0 12px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--accent);
}

.section__label--on-dark { color: #a5b4fc; }

.section__title {
  margin: 0 0 14px;
  font-size: clamp(1.625rem, 3vw, 2.125rem);
  font-weight: 650;
  letter-spacing: -0.035em;
  line-height: 1.2;
  color: var(--text);
}

.section__desc {
  margin: 0;
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--text-secondary);
}

/* Positioning cards */
.position {
  display: grid;
  gap: 16px;
}

@media (min-width: 768px) {
  .position { grid-template-columns: 1fr 1fr; gap: 20px; }
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow-sm);
}

.card--accent {
  background: linear-gradient(165deg, #fafafe 0%, var(--accent-soft) 100%);
  border-color: #c7d2fe;
}

.card__label {
  margin: 0 0 10px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent);
}

.card h3 {
  margin: 0 0 12px;
  font-size: 1.25rem;
  font-weight: 650;
  letter-spacing: -0.025em;
}

.card p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.975rem;
  line-height: 1.7;
}

.check-list {
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.check-list li {
  position: relative;
  padding-left: 26px;
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.55;
}

.check-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.35em;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16' fill='none'%3E%3Cpath d='M4 8.2l2.4 2.4L12 5' stroke='%23fff' stroke-width='1.75' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E") center / 12px no-repeat;
}

/* Layers */
.layers {
  display: grid;
  gap: 16px;
}

@media (min-width: 768px) {
  .layers { grid-template-columns: repeat(3, 1fr); gap: 18px; }
}

.layer {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 24px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.25s var(--ease), transform 0.25s var(--ease), border-color 0.25s var(--ease);
}

.layer:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
  border-color: var(--border-strong);
}

.layer__icon {
  width: 40px;
  height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: var(--accent-soft);
  color: var(--accent);
  margin-bottom: 18px;
}

.layer__num {
  margin: 0 0 8px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--text-muted);
}

.layer h3 {
  margin: 0 0 6px;
  font-size: 1.125rem;
  font-weight: 650;
  letter-spacing: -0.025em;
}

.layer__sub {
  margin: 0 0 14px;
  font-size: 13px;
  color: var(--text-muted);
}

.layer > p:not(.layer__num):not(.layer__sub) {
  margin: 0 0 18px;
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

.chip {
  display: inline-flex;
  align-items: center;
  height: 26px;
  padding: 0 10px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 550;
  background: var(--accent-soft);
  color: var(--accent-ink);
}

.chip--muted {
  background: var(--bg-muted);
  color: var(--text-secondary);
  border: 1px solid var(--border);
}

.chip--live {
  background: var(--live-bg);
  color: var(--live);
}

/* Feature split */
.feature {
  display: grid;
  gap: 32px;
  align-items: start;
}

@media (min-width: 900px) {
  .feature {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 56px;
    align-items: center;
  }
  .feature--reverse .feature__copy { order: 2; }
  .feature--reverse .feature__panel { order: 1; }
}

.feature__copy > p:not(.section__label) {
  margin: 0 0 28px;
  color: var(--text-secondary);
  font-size: 1.025rem;
  line-height: 1.7;
}

.feature__copy h2 {
  margin: 0 0 14px;
  font-size: clamp(1.5rem, 2.8vw, 1.95rem);
  font-weight: 650;
  letter-spacing: -0.035em;
  line-height: 1.25;
}

.steps {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.step {
  display: flex;
  gap: 14px;
  align-items: flex-start;
}

.step__n {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 9px;
  background: var(--indigo-deep);
  color: #fff;
  font-size: 12px;
  font-weight: 650;
}

.step strong {
  display: block;
  font-size: 14.5px;
  letter-spacing: -0.015em;
  margin-bottom: 2px;
}

.step span {
  font-size: 13.5px;
  color: var(--text-muted);
  line-height: 1.45;
}

.feature__panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 28px;
  box-shadow: var(--shadow-md);
}

.section--muted .feature__panel {
  background: #fff;
}

.feature__panel-label {
  margin: 0 0 8px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--accent);
}

.feature__panel h3 {
  margin: 0 0 8px;
  font-size: 1.2rem;
  font-weight: 650;
  letter-spacing: -0.025em;
}

.feature__panel > p {
  margin: 0 0 22px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.pdca {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.pdca__item {
  padding: 14px;
  border-radius: 12px;
  background: var(--bg-muted);
  border: 1px solid var(--border);
}

.pdca__item strong {
  display: block;
  font-size: 13.5px;
  margin-bottom: 2px;
  letter-spacing: -0.015em;
}

.pdca__item span {
  font-size: 12.5px;
  color: var(--text-muted);
}

.mw-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.mw-grid__item {
  padding: 14px;
  border-radius: 12px;
  background: var(--bg-muted);
  border: 1px solid var(--border);
  font-size: 13px;
  font-weight: 530;
  color: var(--text-secondary);
  line-height: 1.4;
}

/* Products */
.products {
  display: grid;
  gap: 14px;
}

@media (min-width: 640px) {
  .products { grid-template-columns: 1fr 1fr; }
}

@media (min-width: 960px) {
  .products { grid-template-columns: repeat(3, 1fr); gap: 16px; }
}

.product {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: box-shadow 0.25s var(--ease), transform 0.25s var(--ease), border-color 0.25s var(--ease);
}

.product:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
  border-color: var(--border-strong);
}

.product--live {
  border-color: #a7f3d0;
  background: linear-gradient(180deg, #fff 0%, #f0fdf9 100%);
}

.product__top {
  margin-bottom: 14px;
}

.product h3 {
  margin: 0 0 4px;
  font-size: 1.125rem;
  font-weight: 650;
  letter-spacing: -0.025em;
}

.product__sub {
  margin: 0 0 12px;
  font-size: 12.5px;
  color: var(--text-muted);
}

.product > p:not(.product__sub) {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  flex: 1;
}

.product__link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 16px;
  font-size: 13.5px;
  font-weight: 560;
  color: var(--accent);
  transition: gap 0.2s var(--ease);
}

.product__link svg {
  width: 14px;
  height: 14px;
}

.product__link:hover { gap: 10px; }

/* Why */
.why {
  display: grid;
  gap: 16px;
}

@media (min-width: 768px) {
  .why { grid-template-columns: repeat(3, 1fr); gap: 18px; }
}

.why__item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 24px;
  box-shadow: var(--shadow-sm);
}

.why__num {
  margin: 0 0 14px;
  font-size: 13px;
  font-weight: 650;
  letter-spacing: 0.02em;
  color: var(--accent);
}

.why__item h3 {
  margin: 0 0 10px;
  font-size: 1.05rem;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.why__item p {
  margin: 0;
  font-size: 0.925rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* CTA */
.cta {
  padding: 80px 0;
}

.cta__inner {
  background: linear-gradient(145deg, #1e1b4b 0%, #312e81 55%, #4338ca 100%);
  border-radius: 24px;
  padding: 40px 32px;
  color: #fff;
  display: grid;
  gap: 28px;
  box-shadow: var(--shadow-lg);
}

@media (min-width: 768px) {
  .cta__inner {
    grid-template-columns: 1.4fr auto;
    align-items: center;
    padding: 48px 48px;
    gap: 40px;
  }
}

.cta__copy h2 {
  margin: 0 0 12px;
  font-size: clamp(1.5rem, 2.8vw, 1.95rem);
  font-weight: 650;
  letter-spacing: -0.035em;
  line-height: 1.25;
}

.cta__copy p:not(.section__label) {
  margin: 0;
  color: rgba(255, 255, 255, 0.78);
  font-size: 1rem;
  line-height: 1.65;
  max-width: 36em;
}

.cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* Footer */
.footer {
  padding: 48px 0 36px;
  border-top: 1px solid var(--border);
  background: var(--bg);
}

.footer__inner {
  display: grid;
  gap: 28px;
  margin-bottom: 32px;
}

@media (min-width: 720px) {
  .footer__inner {
    grid-template-columns: 1.4fr 1fr;
    align-items: start;
  }
}

.footer__brand p {
  margin: 14px 0 0;
  max-width: 28em;
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.footer__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
}

@media (min-width: 720px) {
  .footer__meta {
    justify-content: flex-end;
  }
}

.footer__meta a {
  font-size: 13.5px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.15s var(--ease);
}

.footer__meta a:hover { color: var(--accent); }

.footer__bottom {
  padding-top: 24px;
  border-top: 1px solid var(--border);
  font-size: 12.5px;
  color: var(--text-muted);
}

/* Focus */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}