:root {
  --page-top: #b1c1c7;
  --page-base: #94aab2;
  --bg: #94aab2;
  --bg-soft: #a9bcc3;
  --surface: rgba(255, 255, 255, 0.95);
  --surface-strong: #ffffff;
  --text: #0e262f;
  --text-soft: #28444d;
  --muted: #59717a;
  --primary: #4fb2c4;
  --primary-dark: #1c5664;
  --primary-deep: #143740;
  --primary-soft: #d0ebf0;
  --accent: #84d7e4;
  --line: rgba(14, 38, 47, 0.14);
  --line-strong: rgba(14, 38, 47, 0.22);
  --success: #1f8d68;
  --danger: #d35d67;
  --shadow-sm: 0 10px 24px rgba(8, 26, 32, 0.08);
  --shadow: 0 18px 44px rgba(8, 26, 32, 0.13);
  --shadow-lg: 0 32px 70px rgba(7, 22, 27, 0.18);
  --radius-sm: 14px;
  --radius: 22px;
  --radius-lg: 30px;
  --wrap: 1180px;
  --nav-offset: 112px;
  --transition: 220ms ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Inter, Arial, Helvetica, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(79, 178, 196, 0.12), transparent 30%),
    linear-gradient(180deg, var(--page-top) 0%, var(--page-base) 100%);
  line-height: 1.6;
}

img {
  display: block;
  max-width: 100%;
}

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

button,
input,
select,
textarea {
  font: inherit;
}

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

main section {
  scroll-margin-top: var(--nav-offset);
}

.section-title {
  margin: 0 0 12px;
  color: var(--text);
  font-size: clamp(1.95rem, 3vw, 2.7rem);
  line-height: 1.08;
  letter-spacing: -0.03em;
}

.section-lead {
  margin: 0 0 30px;
  max-width: 760px;
  color: var(--muted);
  font-size: 1.05rem;
  line-height: 1.75;
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(10px);
}

.primary-btn,
.secondary-btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 58px;
  padding: 0 26px;
  border: 0;
  border-radius: 999px;
  cursor: pointer;
  overflow: hidden;
  transition:
    transform var(--transition),
    box-shadow var(--transition),
    background var(--transition),
    border-color var(--transition);
}

.primary-btn {
  color: #ffffff;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  box-shadow: 0 14px 34px rgba(28, 86, 100, 0.28);
}

.primary-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 18px 40px rgba(28, 86, 100, 0.32);
}

.primary-btn:disabled {
  opacity: 0.72;
  cursor: not-allowed;
  transform: none;
}

.secondary-btn {
  color: var(--text);
  background: var(--surface-strong);
  border: 1px solid var(--line-strong);
}

.secondary-btn:hover {
  border-color: var(--primary-dark);
  color: var(--primary-dark);
}

.primary-btn span,
.secondary-btn span {
  position: relative;
  z-index: 2;
  font-weight: 800;
}

.interactive-btn::after {
  content: "";
  position: absolute;
  left: var(--mx, 50%);
  top: var(--my, 50%);
  width: 0;
  height: 0;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.18);
  transform: translate(-50%, -50%);
  transition: width 260ms ease, height 260ms ease, opacity 260ms ease;
  opacity: 0;
  z-index: 1;
}

.interactive-btn:hover::after {
  width: 240px;
  height: 240px;
  opacity: 1;
}

.interactive-btn.clicked {
  transform: scale(0.985);
}