* {
  box-sizing: border-box;
}

:root {
  --bg: #f7f3ed;
  --bg-soft: #fffaf3;
  --text: #211b17;
  --muted: #6e6258;
  --line: rgba(45, 35, 27, 0.14);
  --accent: #9b5c32;
  --accent-dark: #6f3d1f;
  --card: rgba(255, 255, 255, 0.78);
  --shadow: 0 24px 70px rgba(69, 45, 27, 0.13);
  --radius: 28px;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(218, 180, 128, 0.35), transparent 34rem),
    radial-gradient(circle at 90% 10%, rgba(155, 92, 50, 0.18), transparent 28rem),
    var(--bg);
  line-height: 1.65;
}

a {
  color: inherit;
}

.container {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(247, 243, 237, 0.82);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}

.nav {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.logo-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  color: white;
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
  border-radius: 14px;
  box-shadow: 0 10px 25px rgba(111, 61, 31, 0.22);
}

.nav-link {
  padding: 10px 16px;
  color: var(--accent-dark);
  font-weight: 700;
  text-decoration: none;
  border: 1px solid rgba(111, 61, 31, 0.18);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.45);
}

.hero {
  padding: 86px 0 70px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.08fr) minmax(280px, 0.72fr);
  align-items: center;
  gap: 42px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--accent-dark);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  margin: 0;
  line-height: 1.12;
  letter-spacing: -0.045em;
}

h1 {
  max-width: 740px;
  font-size: clamp(3.2rem, 8vw, 6.8rem);
}

h2 {
  font-size: clamp(2rem, 4vw, 3.4rem);
}

h3 {
  margin-top: 38px;
  font-size: clamp(1.35rem, 2vw, 1.9rem);
}

.subtitle {
  margin: 10px 0 22px;
  color: var(--accent-dark);
  font-size: clamp(1.18rem, 2.3vw, 1.65rem);
  font-weight: 800;
}

.lead {
  max-width: 780px;
  margin: 0;
  color: var(--muted);
  font-size: 1.13rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.button,
.small-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 0;
  cursor: pointer;
  font: inherit;
  font-weight: 800;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.button {
  min-height: 50px;
  padding: 13px 22px;
  border-radius: 999px;
}

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

.primary {
  color: #fff;
  background: linear-gradient(135deg, var(--accent), var(--accent-dark));
  box-shadow: 0 16px 36px rgba(111, 61, 31, 0.24);
}

.secondary {
  color: var(--accent-dark);
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(111, 61, 31, 0.18);
}

.hero-card {
  min-height: 330px;
  display: grid;
  align-content: center;
  gap: 26px;
  padding: 34px;
  border: 1px solid rgba(255, 255, 255, 0.7);
  border-radius: var(--radius);
  background:
    linear-gradient(145deg, rgba(255, 255, 255, 0.88), rgba(255, 250, 243, 0.62)),
    radial-gradient(circle at 30% 10%, rgba(155, 92, 50, 0.18), transparent 15rem);
  box-shadow: var(--shadow);
}

.hero-card p {
  margin: 0;
  color: var(--muted);
  font-size: 1.08rem;
  font-weight: 700;
}

.mini-piano {
  height: 170px;
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 7px;
  align-items: end;
}

.mini-piano span {
  display: block;
  height: 100%;
  background: #fff;
  border: 1px solid rgba(45, 35, 27, 0.16);
  border-radius: 0 0 14px 14px;
  box-shadow: inset 0 -16px 22px rgba(45, 35, 27, 0.08);
}

.mini-piano span:nth-child(2),
.mini-piano span:nth-child(4),
.mini-piano span:nth-child(7) {
  height: 78%;
}

.section-soft {
  background: rgba(255, 250, 243, 0.78);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.partners {
  padding: 54px 0;
}

.partners h2 {
  max-width: 760px;
  font-size: clamp(1.8rem, 3vw, 2.8rem);
}

.partner-links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 24px;
}

.partner-links a {
  padding: 16px 22px;
  color: var(--accent-dark);
  font-weight: 900;
  text-decoration: none;
  background: #fff;
  border: 1px solid rgba(111, 61, 31, 0.14);
  border-radius: 18px;
  box-shadow: 0 12px 30px rgba(69, 45, 27, 0.08);
}

.piano-section {
  padding: 80px 0;
}

.section-heading {
  max-width: 800px;
  margin-bottom: 30px;
}

.section-heading p:not(.eyebrow) {
  margin: 18px 0 0;
  color: var(--muted);
  font-size: 1.08rem;
}

.piano-panel {
  padding: clamp(18px, 3vw, 30px);
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(255, 255, 255, 0.86);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.piano-toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 20px;
}

.small-button {
  min-height: 44px;
  padding: 10px 16px;
  color: #fff;
  background: var(--accent-dark);
  border-radius: 14px;
}

.volume-control {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--muted);
  font-weight: 800;
}

.volume-control input {
  accent-color: var(--accent-dark);
}

.piano {
  --white-count: 14;
  --white-width: calc(100% / var(--white-count));
  position: relative;
  display: flex;
  min-height: clamp(230px, 32vw, 330px);
  padding: 0 2px 2px;
  overflow: hidden;
  user-select: none;
  touch-action: none;
  background: #181513;
  border: 12px solid #181513;
  border-radius: 22px;
  box-shadow: inset 0 -12px 0 rgba(255, 255, 255, 0.04), 0 20px 45px rgba(33, 27, 23, 0.22);
}

.key {
  position: relative;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  padding-bottom: 16px;
  border: 0;
  cursor: pointer;
  font-family: inherit;
  font-weight: 900;
  transition: transform 0.05s ease, background 0.05s ease, box-shadow 0.05s ease;
}

.key.white {
  z-index: 1;
  flex: 0 0 var(--white-width);
  height: 100%;
  min-height: inherit;
  color: #2c2520;
  background: linear-gradient(#ffffff 0%, #fffdfa 54%, #eadfd1 100%);
  border-right: 1px solid rgba(24, 21, 19, 0.24);
  border-radius: 0 0 12px 12px;
  box-shadow: inset 0 -18px 18px rgba(75, 52, 34, 0.12);
}

.key.white:first-child {
  border-left: 1px solid rgba(24, 21, 19, 0.16);
}

.key.black {
  --black-width: calc(var(--white-width) * 0.62);
  position: absolute;
  top: 0;
  left: calc((var(--i) + 1) * var(--white-width) - (var(--black-width) / 2));
  z-index: 2;
  width: var(--black-width);
  height: 62%;
  color: rgba(255, 255, 255, 0.9);
  background: linear-gradient(90deg, #12100f, #302720 52%, #0f0d0c);
  border-radius: 0 0 10px 10px;
  box-shadow: inset 0 -18px 12px rgba(255, 255, 255, 0.05), 0 8px 14px rgba(0, 0, 0, 0.32);
}

.key.active,
.key:active {
  transform: translateY(3px);
}

.key.white.active,
.key.white:active {
  background: linear-gradient(#f6ede2, #e0c6aa);
  box-shadow: inset 0 -8px 12px rgba(75, 52, 34, 0.2);
}

.key.black.active,
.key.black:active {
  background: linear-gradient(90deg, #050404, #17120f 55%, #050404);
}

.key-label {
  display: grid;
  gap: 2px;
  text-align: center;
  pointer-events: none;
}

.note {
  font-size: 0.78rem;
  opacity: 0.7;
}

.keyboard-key {
  font-size: 1rem;
}

.hint {
  margin: 18px 0 0;
  color: var(--muted);
}

kbd {
  display: inline-block;
  min-width: 1.8em;
  padding: 0.08em 0.42em;
  color: var(--accent-dark);
  font: inherit;
  font-weight: 900;
  text-align: center;
  background: #fff;
  border: 1px solid rgba(111, 61, 31, 0.18);
  border-radius: 8px;
  box-shadow: inset 0 -2px 0 rgba(111, 61, 31, 0.12);
}

.article-section {
  padding: 76px 0;
}

.article-card {
  max-width: 920px;
  margin: 0 auto;
  padding: clamp(22px, 4vw, 48px);
  background: rgba(255, 255, 255, 0.82);
  border: 1px solid rgba(255, 255, 255, 0.92);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.article-card h2 {
  margin-bottom: 24px;
}

.article-card p,
.article-card li {
  color: #51463e;
  font-size: 1.05rem;
}

.article-card p {
  margin: 18px 0 0;
}

.article-card ul {
  margin: 18px 0 0;
  padding-left: 22px;
}

.article-card li + li {
  margin-top: 8px;
}

.site-footer {
  padding: 30px 0;
  color: rgba(255, 255, 255, 0.82);
  background: #181513;
}

.footer-inner {
  display: flex;
  justify-content: center;
  text-align: center;
}

.site-footer p {
  margin: 0;
}

.site-footer a {
  color: #fff;
  font-weight: 900;
  text-decoration: none;
}

@media (max-width: 860px) {
  .hero {
    padding-top: 56px;
  }

  .hero-grid {
    grid-template-columns: 1fr;
  }

  .hero-card {
    min-height: 240px;
  }

  .piano {
    overflow-x: auto;
    min-width: 760px;
  }

  .piano-panel {
    overflow-x: auto;
  }

  .key {
    padding-bottom: 12px;
  }

  .note {
    font-size: 0.7rem;
  }

  .keyboard-key {
    font-size: 0.92rem;
  }
}

@media (max-width: 560px) {
  .nav {
    min-height: 64px;
  }

  .nav-link {
    display: none;
  }

  .hero-actions {
    flex-direction: column;
  }

  .button {
    width: 100%;
  }

  .partner-links a {
    width: 100%;
  }

  .piano-toolbar {
    align-items: flex-start;
    flex-direction: column;
  }
}