:root {
  --bg: #f6f1e8;
  --paper: #fffaf2;
  --surface: #f1e4d2;
  --ink: #1e2a39;
  --muted: #5d6570;
  --blue: #2f5f98;
  --blue-deep: #203f69;
  --orange: #e57f42;
  --gold: #d4a847;
  --green: #6f8b54;
  --line: rgba(30, 42, 57, 0.12);
  --shadow: 0 20px 50px rgba(29, 39, 57, 0.12);
  --radius: 28px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Manrope", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(229, 127, 66, 0.16), transparent 30%),
    radial-gradient(circle at right 20%, rgba(47, 95, 152, 0.12), transparent 25%),
    linear-gradient(180deg, #fbf7f0 0%, var(--bg) 100%);
}

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

.hero,
.section,
.value-band {
  width: min(1160px, calc(100% - 32px));
  margin: 0 auto;
}

.hero {
  padding: 12px 0 48px;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 14px 18px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 250, 242, 0.8);
  backdrop-filter: blur(12px);
}

.brand {
  font-weight: 800;
  letter-spacing: 0.03em;
}

.nav-link {
  font-size: 0.96rem;
  color: var(--muted);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 28px;
  align-items: center;
  padding-top: 12px;
}

.eyebrow,
.section-kicker,
.mini-badge,
.video-label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border-radius: 999px;
  background: rgba(47, 95, 152, 0.1);
  color: var(--blue-deep);
  font-size: 0.88rem;
  font-weight: 700;
}

h1,
h2,
h3 {
  margin: 0;
}

h1,
.section-heading h2,
.cta-box h2 {
  font-family: "Prata", serif;
  font-weight: 400;
  line-height: 1.1;
}

h1 {
  margin-top: 18px;
  font-size: clamp(2.8rem, 6vw, 5.2rem);
  max-width: 10ch;
}

.hero-text,
.section-heading p,
.feature-card p,
.steam-card p,
.lesson-card p,
.panel p,
.video-frame p,
.calc-card p,
.proof-card p,
.cta-box p,
.footer p {
  color: var(--muted);
  line-height: 1.7;
}

.hero-text {
  font-size: 1.08rem;
  max-width: 60ch;
  margin: 18px 0 0;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 24px;
}

.hero-note {
  margin: 16px 0 0;
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--blue-deep);
}

.brand-chip {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  min-height: 74px;
  padding: 12px 16px;
  border-radius: 22px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.68);
  box-shadow: 0 12px 28px rgba(32, 63, 105, 0.06);
}

.brand-chip-icon,
.brand-chip-logo {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  border-radius: 18px;
  background: linear-gradient(145deg, #d8e7fb, #eef4fb);
  color: var(--blue-deep);
  font-size: 0.95rem;
  font-weight: 800;
  letter-spacing: 0.05em;
}

.brand-chip-logo {
  object-fit: cover;
  padding: 4px;
  background: rgba(255, 255, 255, 0.92);
}

.brand-chip-text {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.brand-chip-text strong {
  font-size: 0.98rem;
  line-height: 1.2;
}

.brand-chip-text small {
  color: var(--muted);
  font-size: 0.84rem;
  line-height: 1.3;
}

.brand-chip-steam {
  background: linear-gradient(145deg, rgba(255, 245, 233, 0.9), rgba(255, 255, 255, 0.78));
}

.steam-mark {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  height: 56px;
  border-radius: 18px;
  background: linear-gradient(145deg, #fff0df, #fff8f0);
  box-shadow: inset 0 0 0 1px rgba(229, 127, 66, 0.16);
}

.steam-dot {
  position: absolute;
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.steam-dot-s {
  top: 10px;
  left: 11px;
  background: #2f5f98;
}

.steam-dot-t {
  top: 8px;
  right: 12px;
  background: #e57f42;
}

.steam-dot-e {
  bottom: 18px;
  left: 10px;
  background: #6f8b54;
}

.steam-dot-a {
  bottom: 10px;
  right: 13px;
  background: #d4a847;
}

.steam-dot-m {
  width: 16px;
  height: 16px;
  top: 20px;
  left: 20px;
  background: #203f69;
}

  .hero-actions {
    display: flex;
    gap: 14px;
    margin: 28px 0 22px;
    flex-wrap: wrap;
}

.button {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  min-height: 52px;
  padding: 0 24px;
  border-radius: 16px;
  font-weight: 800;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button-primary {
  background: linear-gradient(135deg, var(--orange), #f29e54);
  color: #fff;
  box-shadow: 0 14px 30px rgba(229, 127, 66, 0.28);
}

.button-secondary {
  border: 1px solid rgba(47, 95, 152, 0.18);
  background: rgba(255, 255, 255, 0.6);
  color: var(--blue-deep);
}

.button-card {
  background: #f5f7e8;
  border: 1px solid rgba(111, 139, 84, 0.4);
  color: #2f4532;
}

.light-border {
  border-color: rgba(255, 255, 255, 0.3);
  color: #fff;
}

.hero-points {
  display: grid;
  gap: 12px;
  padding: 0;
  margin: 0;
  list-style: none;
}

.hero-points li {
  position: relative;
  padding-left: 24px;
  color: var(--muted);
}

.hero-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--orange);
}

.hero-card {
  position: relative;
}

.hero-card::before {
  content: "";
  position: absolute;
  inset: -18px 26px 18px -18px;
  background: linear-gradient(135deg, rgba(47, 95, 152, 0.12), rgba(212, 168, 71, 0.14));
  border-radius: 40px;
  z-index: 0;
}

.mini-card {
  position: relative;
  z-index: 1;
  padding: 28px;
  border-radius: 30px;
  background: var(--paper);
  box-shadow: var(--shadow);
  border: 1px solid rgba(30, 42, 57, 0.08);
}

.mini-card-head {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
}

.mini-time {
  font-weight: 700;
  color: var(--blue-deep);
}

.mini-card h2 {
  margin-top: 18px;
  font-size: 2rem;
}

.mini-problem {
  margin: 12px 0 0;
  font-size: 1.1rem;
}

.mini-meta {
  display: grid;
  gap: 12px;
  padding: 0;
  margin: 20px 0 24px;
  list-style: none;
}

.mini-meta li {
  color: var(--muted);
  line-height: 1.6;
}

blockquote {
  margin: 22px 0 0;
  padding: 16px 18px;
  border-left: 4px solid var(--gold);
  background: rgba(212, 168, 71, 0.1);
  border-radius: 18px;
  font-style: italic;
  color: var(--ink);
}

.value-band {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 8px;
}

.value-item {
  padding: 24px 20px;
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--line);
  text-align: center;
}

.value-number {
  display: block;
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 800;
  color: var(--blue-deep);
}

.value-label {
  display: block;
  margin-top: 8px;
  color: var(--muted);
}

.section {
  padding: 88px 0 0;
}

.section-heading {
  max-width: 780px;
}

.section-heading h2 {
  margin-top: 16px;
  font-size: clamp(2rem, 4vw, 3.5rem);
}

.section-heading p:last-child {
  margin-top: 16px;
}

.feature-grid,
.lesson-grid,
.proof-grid,
.authors-grid,
.contact-grid {
  display: grid;
  gap: 18px;
  margin-top: 28px;
}

.feature-grid {
  grid-template-columns: repeat(4, 1fr);
}

.feature-card,
.lesson-card,
.proof-card {
  padding: 24px;
  border-radius: 24px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.68);
}

.feature-card h3,
.lesson-card h3,
.panel h3,
.video-frame h3,
.calc-card h3 {
  font-size: 1.3rem;
}

.steam-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
  margin-top: 28px;
}

.steam-card {
  padding: 22px 18px;
  border-radius: 24px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.76), rgba(255, 255, 255, 0.52));
  border: 1px solid var(--line);
  min-height: 220px;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.steam-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow);
}

.steam-letter {
  display: inline-flex;
  width: 52px;
  height: 52px;
  border-radius: 16px;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  font-weight: 800;
  background: rgba(47, 95, 152, 0.14);
  color: var(--blue-deep);
}

.lesson-grid {
  grid-template-columns: repeat(4, 1fr);
}

.authors-grid {
  grid-template-columns: repeat(2, 1fr);
  margin-top: 18px;
}

.contact-grid {
  grid-template-columns: 1.1fr 0.9fr;
}

.authors-section .section-heading {
  margin-bottom: 10px;
}

.authors-section {
  padding-bottom: 56px;
}

.lesson-card {
  position: relative;
  overflow: hidden;
  min-height: 220px;
  display: flex;
  flex-direction: column;
}

.lesson-card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.22), transparent 60%);
}

.lesson-tag {
  position: relative;
  display: inline-flex;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.58);
  font-weight: 700;
}

.lesson-card h3,
.lesson-card p,
.lesson-card a {
  position: relative;
}

.lesson-card h3 {
  margin-top: 18px;
}

.lesson-card a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: fit-content;
  min-height: 46px;
  padding: 0 18px;
  font-weight: 800;
  margin-top: auto;
  margin-bottom: 4px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(32, 63, 105, 0.1);
  box-shadow: 0 10px 22px rgba(32, 63, 105, 0.08);
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.lesson-card a:hover {
  transform: translateY(-2px);
  background: #ffffff;
  box-shadow: 0 14px 28px rgba(32, 63, 105, 0.12);
}

.author-card {
  display: flex;
  flex-direction: column;
  min-height: 320px;
  padding: 28px 28px 44px;
  border-radius: 28px;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.author-card-primary {
  background: linear-gradient(145deg, #dcecff, #f5f1e8 78%);
}

.author-card-secondary {
  background: linear-gradient(145deg, #f8dfd6, #f5f1e8 78%);
}

.author-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
}

.author-pill {
  display: inline-flex;
  padding: 8px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.72);
  color: var(--blue-deep);
  font-weight: 700;
}

.author-monogram {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 76px;
  height: 76px;
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.7);
  color: var(--blue-deep);
  font-size: 1.8rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  box-shadow: 0 12px 24px rgba(32, 63, 105, 0.08);
}

.author-body {
  margin-top: 36px;
  padding-top: 0;
}

.author-body h3 {
  font-size: 1.9rem;
  line-height: 1.2;
}

.author-body p {
  margin: 16px 0 0;
  color: var(--muted);
  line-height: 1.7;
}

.contact-card {
  padding: 28px;
  border-radius: 28px;
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.contact-card-qr {
  background: linear-gradient(145deg, rgba(255, 255, 255, 0.82), rgba(246, 241, 232, 0.92));
}

.contact-card-info {
  background: linear-gradient(145deg, #f3e7d4, #fbf5ea);
}

.contact-card h3 {
  font-size: 1.45rem;
}

.contact-qr-text {
  margin: 16px 0 0;
  color: var(--muted);
  line-height: 1.7;
}

.contact-qr-wrap {
  margin-top: 22px;
  padding: 18px;
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.76);
  border: 1px solid rgba(32, 63, 105, 0.08);
  display: flex;
  justify-content: center;
}

.contact-qr-image {
  width: min(100%, 340px);
  display: block;
  border-radius: 24px;
  box-shadow: 0 16px 32px rgba(32, 63, 105, 0.08);
}

.contact-list {
  display: grid;
  gap: 16px;
  margin-top: 20px;
}

.contact-label {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--blue-deep);
}

.contact-item {
  padding: 18px 20px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.64);
  border: 1px solid rgba(32, 63, 105, 0.08);
}

.contact-item strong {
  display: block;
  margin-top: 6px;
  font-size: 1.02rem;
  line-height: 1.45;
}

.accent-blue {
  background: linear-gradient(145deg, #dcecff, #eff5fb);
}

.accent-sand {
  background: linear-gradient(145deg, #f3e7d4, #fbf5ea);
}

.accent-coral {
  background: linear-gradient(145deg, #f7ddd4, #fff1eb);
}

.accent-green {
  background: linear-gradient(145deg, #dde8d4, #f4f9ee);
}

.accent-navy {
  background: linear-gradient(145deg, #d8e4ef, #edf4fa);
}

.accent-gold {
  background: linear-gradient(145deg, #f0e6c8, #faf5e2);
}

.split-grid,
.video-calc-section {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 22px;
  margin-top: 28px;
}

.panel,
.video-frame,
.calc-card,
.cta-box {
  border-radius: 28px;
  padding: 28px;
  box-shadow: var(--shadow);
}

.panel-light {
  background: rgba(255, 255, 255, 0.75);
  border: 1px solid var(--line);
}

.panel-dark {
  background: linear-gradient(160deg, #264461, #1b2f45);
  color: #fff;
}

.panel-dark p,
.panel-dark li {
  color: rgba(255, 255, 255, 0.82);
}

.panel-subtitle {
  margin: 10px 0 20px;
}

.checklist,
.material-list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding-left: 20px;
}

.checklist li,
.material-list li {
  line-height: 1.6;
}

.video-card,
.calc-card {
  align-self: stretch;
}

.video-frame {
  height: 100%;
  min-height: 320px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  background:
    linear-gradient(160deg, rgba(32, 63, 105, 0.95), rgba(28, 44, 69, 0.88)),
    radial-gradient(circle at top left, rgba(229, 127, 66, 0.45), transparent 30%);
  color: #fff;
}

.video-frame p {
  color: rgba(255, 255, 255, 0.82);
}

.calc-card {
  background: rgba(255, 255, 255, 0.75);
  border: 1px solid var(--line);
}

label {
  display: block;
  margin: 22px 0 10px;
  font-weight: 700;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--orange);
}

.calc-results {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  margin-top: 20px;
}

.calc-results div {
  padding: 20px;
  border-radius: 20px;
  background: rgba(47, 95, 152, 0.08);
}

.calc-caption {
  display: block;
  color: var(--muted);
  margin-bottom: 8px;
}

.calc-results strong,
.proof-metric {
  font-size: 1.5rem;
  color: var(--blue-deep);
}

.proof-grid {
  grid-template-columns: repeat(3, 1fr);
}

.cta-section {
  padding-bottom: 88px;
}

.cta-box {
  text-align: center;
  background: linear-gradient(145deg, #fff7eb, #fffdf8);
  border: 1px solid rgba(229, 127, 66, 0.2);
}

.cta-box .button {
  margin-top: 16px;
}

@media (max-width: 1024px) {
  .hero-grid,
  .feature-grid,
  .split-grid,
  .video-calc-section,
  .lesson-grid,
  .proof-grid,
  .authors-grid,
  .contact-grid,
  .steam-grid,
  .value-band {
    grid-template-columns: repeat(2, 1fr);
  }

  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .lesson-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 720px) {
  .topbar,
  .hero-grid,
  .value-band,
  .feature-grid,
  .steam-grid,
  .lesson-grid,
  .authors-grid,
  .contact-grid,
  .split-grid,
  .video-calc-section,
  .proof-grid {
    grid-template-columns: 1fr;
  }

  .topbar {
    border-radius: 28px;
    align-items: flex-start;
  }

  .hero {
    padding-top: 8px;
  }

  .hero-badges {
    flex-direction: column;
    align-items: stretch;
  }

  .brand-chip {
    width: 100%;
  }

  h1 {
    max-width: none;
  }

  .section {
    padding-top: 68px;
  }

  .value-band {
    gap: 12px;
  }

  .calc-results {
    grid-template-columns: 1fr;
  }

  .author-card {
    min-height: auto;
  }

  .author-body {
    margin-top: 24px;
    padding-top: 0;
  }
}