:root {
  color-scheme: light;
  --bg: #f7fbff;
  --panel: #ffffff;
  --text: #101b31;
  --muted: #64748b;
  --line: #e1e9f5;
  --primary: #1557ff;
  --primary-2: #3b82f6;
  --green: #10b981;
  --orange: #f97316;
  --yellow: #f59e0b;
  --teal: #14b8a6;
  --rose: #fb7185;
  --violet: #8b5cf6;
  --shadow: 0 22px 70px rgba(38, 83, 166, 0.15);
  --radius: 16px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  color: var(--text);
  background: var(--bg);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

button,
input {
  font: inherit;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

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

svg {
  width: 24px;
  height: 24px;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 2.15;
}

.icon-defs {
  position: absolute;
  width: 0;
  height: 0;
  overflow: hidden;
}

.site-header {
  position: sticky;
  height: 64px;
  padding: 0 34px;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 22px;
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
  top: 0;
  z-index: 10;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.brand-icon {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  background: var(--primary);
  color: white;
  box-shadow: 0 10px 24px rgba(21, 87, 255, 0.24);
}

.brand-icon svg {
  width: 23px;
  height: 23px;
}

.brand strong {
  display: block;
  font-size: 20px;
  line-height: 1.15;
  letter-spacing: 0;
}

.brand small {
  display: block;
  margin-top: 3px;
  color: var(--muted);
  font-size: 12px;
}

.nav-links {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  gap: 34px;
  height: 100%;
  font-size: 15px;
  font-weight: 700;
}

.nav-links a {
  height: 100%;
  display: grid;
  place-items: center;
  color: #111827;
  position: relative;
}

.nav-links a.active,
.nav-links a:hover {
  color: var(--primary);
}

.nav-links a.active::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  border-radius: 999px;
  background: var(--primary);
}

main {
  flex: 1;
  overflow: hidden;
}

.site-footer {
  padding: 0 20px 22px;
  text-align: center;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.6;
}

.site-footer a {
  color: inherit;
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--primary);
  text-decoration: underline;
}

.hero {
  max-width: 1460px;
  min-height: 384px;
  margin: 0 auto;
  padding: 62px 52px 20px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(440px, 0.95fr);
  gap: 38px;
  align-items: center;
}

.hero-copy h1 {
  margin: 0;
  font-size: clamp(48px, 5vw, 72px);
  line-height: 1.08;
  letter-spacing: 0;
  color: #081735;
}

.hero-copy h1 span,
.hero-copy p span {
  color: var(--primary);
}

.hero-copy p {
  margin: 24px 0 36px;
  font-size: clamp(21px, 2vw, 28px);
  line-height: 1.45;
  font-weight: 850;
  letter-spacing: 0;
}

.hero-features {
  display: flex;
  flex-wrap: wrap;
  gap: 34px;
}

.hero-features div {
  display: grid;
  grid-template-columns: 52px 1fr;
  column-gap: 14px;
  align-items: center;
}

.hero-features span {
  grid-row: span 2;
  width: 52px;
  height: 52px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--primary);
  color: white;
  box-shadow: 0 10px 28px rgba(21, 87, 255, 0.25);
}

.hero-features strong {
  font-size: 16px;
}

.hero-features small {
  color: var(--muted);
  font-size: 13px;
}

.hero-visual {
  min-height: 320px;
  position: relative;
}

.hero-search-bubble {
  position: absolute;
  top: 0;
  left: 60px;
  z-index: 2;
  width: 360px;
  min-height: 64px;
  padding: 0 14px 0 26px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  border: 2px solid rgba(255, 255, 255, 0.92);
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.76);
  color: #7c8799;
  box-shadow: 0 16px 44px rgba(71, 119, 204, 0.15);
  transform: rotate(6deg);
}

.bubble-button {
  width: 44px;
  height: 44px;
  border-radius: 11px;
  display: grid;
  place-items: center;
  background: var(--primary);
  color: white;
}

.bot-scene {
  position: absolute;
  right: 0;
  bottom: 0;
  width: min(560px, 100%);
  height: 285px;
}

.laptop {
  position: absolute;
  left: 70px;
  bottom: 20px;
  width: 280px;
  height: 132px;
  border: 10px solid #d8e8ff;
  border-bottom-width: 20px;
  border-radius: 22px 22px 28px 28px;
  background: linear-gradient(145deg, #ffffff, #dfeeff);
  box-shadow: 0 28px 42px rgba(77, 126, 204, 0.15);
}

.laptop::after {
  content: "";
  position: absolute;
  left: -36px;
  right: -36px;
  bottom: -42px;
  height: 28px;
  border-radius: 0 0 42px 42px;
  background: #e6f0ff;
}

.bot {
  position: absolute;
  left: 128px;
  bottom: 24px;
  width: 148px;
  height: 190px;
}

.bot-antenna {
  position: absolute;
  left: 68px;
  top: 0;
  width: 12px;
  height: 34px;
  border-radius: 999px;
  background: #75a8ff;
}

.bot-antenna::before {
  content: "";
  position: absolute;
  left: -8px;
  top: -12px;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: #8eb8ff;
  box-shadow: inset 0 -8px 12px rgba(21, 87, 255, 0.22);
}

.bot-head {
  position: absolute;
  left: 13px;
  top: 26px;
  width: 122px;
  height: 86px;
  border: 8px solid #cfe2ff;
  border-radius: 38px;
  background: #0c1a3a;
  box-shadow: inset 0 -12px 22px rgba(47, 105, 255, 0.28), 0 14px 28px rgba(21, 87, 255, 0.16);
}

.bot-head span {
  position: absolute;
  top: 32px;
  width: 16px;
  height: 22px;
  border: 6px solid #48c7ff;
  border-bottom: 0;
  border-radius: 16px 16px 0 0;
}

.bot-head span:first-child {
  left: 30px;
}

.bot-head span:last-child {
  right: 30px;
}

.bot-body {
  position: absolute;
  left: 35px;
  top: 108px;
  width: 78px;
  height: 70px;
  display: grid;
  place-items: center;
  border: 7px solid #d7e8ff;
  border-radius: 26px 26px 20px 20px;
  background: #ffffff;
  color: var(--primary);
}

.bot-arm {
  position: absolute;
  left: -4px;
  top: 94px;
  width: 26px;
  height: 72px;
  border-radius: 16px;
  background: #76aaff;
  transform: rotate(-34deg);
  transform-origin: top center;
}

.bot-arm::after {
  content: "";
  position: absolute;
  left: -4px;
  bottom: -4px;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: #2f72ff;
}

.books-stack {
  position: absolute;
  right: 12px;
  bottom: 18px;
  width: 200px;
  height: 226px;
}

.book-main,
.book-side {
  position: absolute;
  bottom: 0;
  border-radius: 10px;
  box-shadow: 0 18px 34px rgba(22, 85, 230, 0.22);
}

.book-main {
  left: 0;
  z-index: 3;
  width: 124px;
  height: 202px;
  display: grid;
  place-items: center;
  color: white;
  background: linear-gradient(145deg, #4d8eff, #1557ff);
  transform: rotate(8deg);
}

.book-main svg {
  width: 64px;
  height: 64px;
  opacity: 0.48;
}

.book-side {
  right: 40px;
  width: 86px;
  height: 190px;
  background: #3f7dfa;
  transform: rotate(10deg);
}

.book-side.deep {
  right: 0;
  width: 76px;
  height: 180px;
  background: #1e55d8;
}

.sparkle {
  position: absolute;
  color: #cfe3ff;
}

.sparkle.one {
  top: 30px;
  right: 72px;
  width: 48px;
  height: 48px;
}

.sparkle.two {
  left: 24px;
  top: 120px;
  width: 42px;
  height: 42px;
}

.workflow {
  max-width: 1434px;
  margin: 0 auto 40px;
  padding: 38px 36px 30px;
  display: grid;
  grid-template-columns: 0.92fr 0.88fr 1.55fr;
  gap: 26px;
  background: rgba(255, 255, 255, 0.96);
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.step {
  min-width: 0;
  position: relative;
}

.step + .step::before {
  content: "";
  position: absolute;
  left: -13px;
  top: 16px;
  bottom: 54px;
  width: 1px;
  background: var(--line);
}

.step-head {
  min-height: 50px;
  margin-bottom: 25px;
  display: flex;
  align-items: center;
  gap: 14px;
}

.step-head b {
  color: var(--primary);
  font-size: 32px;
  line-height: 1;
}

.step-head strong,
.examples strong {
  display: block;
  font-size: 16px;
}

.step-head small {
  display: block;
  margin-top: 5px;
  color: var(--muted);
  font-size: 13px;
}

.subject-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.subject-card,
.range-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: white;
  color: #111827;
  text-align: left;
  font-weight: 850;
}

.subject-card {
  min-height: 50px;
  padding: 10px 14px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.subject-card span,
.benefits span {
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  border-radius: 8px;
}

.green {
  background: #dcfce7;
  color: var(--green);
}

.orange {
  background: #ffedd5;
  color: var(--orange);
}

.blue-soft {
  background: #dbeafe;
  color: var(--primary);
}

.yellow {
  background: #fef3c7;
  color: var(--yellow);
}

.teal {
  background: #ccfbf1;
  color: var(--teal);
}

.violet {
  background: #ede9fe;
  color: var(--violet);
}

.rose {
  background: #ffe4e6;
  color: var(--rose);
}

.sky {
  background: #dbeafe;
  color: #0ea5e9;
}

.range-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

.range-card {
  min-height: 72px;
  padding: 14px;
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 12px;
  align-items: center;
}

.range-icon {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  background: #eef5ff;
  color: var(--primary);
}

.range-card small {
  display: block;
  margin-top: 6px;
  color: var(--muted);
}

.search-panel {
  min-height: 278px;
  padding: 22px 18px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: white;
}

.search-box {
  height: 70px;
  padding: 0 12px 0 28px;
  display: grid;
  grid-template-columns: 1fr 58px;
  gap: 14px;
  align-items: center;
  border: 1.5px solid #a7c3ff;
  border-radius: 16px;
  box-shadow: 0 0 0 4px rgba(21, 87, 255, 0.05);
  cursor: pointer;
}

.search-box:hover {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(21, 87, 255, 0.08);
}

.search-placeholder {
  color: #97a3b6;
  font-size: 15px;
}

.search-button {
  width: 58px;
  height: 58px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  background: var(--primary);
  color: white;
  box-shadow: 0 14px 30px rgba(21, 87, 255, 0.24);
}

.search-button svg {
  width: 32px;
  height: 32px;
}

.examples {
  margin-top: 25px;
}

.examples div {
  margin-top: 12px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.examples a {
  min-height: 38px;
  padding: 0 16px;
  display: inline-flex;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: white;
  color: #374151;
  font-size: 14px;
}

.benefits {
  grid-column: 1 / -1;
  margin-top: 16px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.benefits div {
  display: grid;
  grid-template-columns: 38px 1fr;
  column-gap: 14px;
  align-items: center;
}

.benefits span {
  grid-row: span 2;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: #eaf2ff;
  color: var(--primary);
}

.benefits small {
  margin-top: 5px;
  color: var(--muted);
  font-size: 13px;
}

@media (max-width: 1180px) {
  .site-header {
    padding: 0 24px;
  }

  .nav-links {
    gap: 22px;
  }

  .hero {
    grid-template-columns: 1fr;
    padding-top: 42px;
  }

  .hero-visual {
    display: none;
  }

  .workflow {
    margin: 0 18px 32px;
    grid-template-columns: 1fr;
  }

  .step + .step::before {
    display: none;
  }
}

@media (max-width: 720px) {
  .site-header {
    height: auto;
    padding: 18px;
    align-items: flex-start;
    flex-wrap: wrap;
  }

  .nav-links {
    order: 3;
    width: 100%;
    height: 42px;
    overflow-x: auto;
  }

  .brand strong {
    font-size: 21px;
  }

  .brand small {
    font-size: 12px;
  }

  .hero {
    padding: 34px 20px 18px;
  }

  .hero-copy p {
    margin-bottom: 26px;
  }

  .hero-features {
    gap: 18px;
  }

  .workflow {
    padding: 22px 16px;
  }

  .subject-grid,
  .range-grid,
  .benefits {
    grid-template-columns: 1fr;
  }

  .search-box {
    height: auto;
    min-height: 64px;
    grid-template-columns: 1fr 50px;
    padding-left: 16px;
  }

  .search-button {
    width: 50px;
    height: 50px;
  }
}