/* Pulseline — Website Styles
   Palette: Apple-inspired light theme + heart red accent
   Font: Inter (Google Fonts) */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

:root {
  /* Color palette */
  --color-bg: #ffffff;
  --color-bg-alt: #f5f5f7;
  --color-text: #1d1d1f;
  --color-text-muted: rgba(0, 0, 0, 0.64);
  --color-text-subtle: rgba(0, 0, 0, 0.48);
  --color-border: rgba(0, 0, 0, 0.08);
  --color-border-strong: rgba(0, 0, 0, 0.16);

  /* Accent — heart / pulse */
  --color-accent: #ff3b30;
  --color-accent-hover: #e0302a;
  --color-accent-soft: #ffe5e3;

  /* Link */
  --color-link: #0066cc;

  /* Spacing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  --space-4xl: 96px;

  /* Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-pill: 980px;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.08);
  --shadow-card: 0 3px 30px rgba(0, 0, 0, 0.08);

  /* Layout */
  --container: 1080px;
  --container-narrow: 760px;

  /* Motion */
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'SF Pro Text', 'Helvetica Neue', Arial, sans-serif;
  font-size: 17px;
  line-height: 1.47;
  color: var(--color-text);
  background: var(--color-bg);
  letter-spacing: -0.011em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: var(--color-link);
  text-decoration: none;
  transition: color 200ms var(--ease);
}

a:hover {
  text-decoration: underline;
}

h1, h2, h3, h4 {
  margin: 0;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--color-text);
}

p {
  margin: 0;
}

/* =================== Layout =================== */

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.container--narrow {
  max-width: var(--container-narrow);
}

.section {
  padding: var(--space-4xl) 0;
}

.section--alt {
  background: var(--color-bg-alt);
}

.section--tight {
  padding: var(--space-3xl) 0;
}

/* =================== Header / Nav =================== */

.header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--color-border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.nav__brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-weight: 700;
  font-size: 17px;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

.nav__brand:hover {
  text-decoration: none;
}

.nav__logo {
  width: 28px;
  height: 28px;
  color: var(--color-accent);
}

.nav__menu {
  display: flex;
  align-items: center;
  gap: var(--space-xl);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav__link {
  color: var(--color-text);
  font-size: 14px;
  font-weight: 400;
  opacity: 0.8;
  transition: opacity 200ms var(--ease);
}

.nav__link:hover {
  opacity: 1;
  text-decoration: none;
}

.nav__link[aria-current="page"] {
  opacity: 1;
  font-weight: 500;
}

.nav__toggle {
  display: none;
  background: none;
  border: 0;
  padding: 8px;
  cursor: pointer;
  color: var(--color-text);
}

/* =================== Buttons =================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 12px 22px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-family: inherit;
  font-size: 15px;
  font-weight: 500;
  line-height: 1;
  cursor: pointer;
  text-decoration: none;
  transition: background 200ms var(--ease), color 200ms var(--ease), border-color 200ms var(--ease), transform 200ms var(--ease);
  white-space: nowrap;
}

.btn:hover {
  text-decoration: none;
}

.btn--primary {
  background: var(--color-accent);
  color: #fff;
}

.btn--primary:hover {
  background: var(--color-accent-hover);
}

.btn--secondary {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border-strong);
}

.btn--secondary:hover {
  background: var(--color-text);
  color: #fff;
  border-color: var(--color-text);
}

.btn--lg {
  padding: 16px 28px;
  font-size: 17px;
}

.btn:focus-visible {
  outline: 3px solid rgba(0, 102, 204, 0.4);
  outline-offset: 2px;
}

/* =================== Hero =================== */

.hero {
  padding: var(--space-4xl) 0 var(--space-3xl);
  text-align: center;
}

.hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 6px 14px;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  border-radius: var(--radius-pill);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0;
  margin-bottom: var(--space-lg);
}

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

.hero__title {
  font-size: clamp(40px, 7vw, 72px);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-lg);
}

.hero__title em {
  font-style: normal;
  background: linear-gradient(135deg, var(--color-accent) 0%, #ff7a73 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero__subtitle {
  max-width: 620px;
  margin: 0 auto var(--space-xl);
  font-size: clamp(17px, 2vw, 21px);
  line-height: 1.45;
  color: var(--color-text-muted);
  font-weight: 400;
}

.hero__actions {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: var(--space-2xl);
}

.hero__visual {
  margin-top: var(--space-2xl);
  display: flex;
  justify-content: center;
}

.hero__phone {
  width: 100%;
  max-width: 320px;
  aspect-ratio: 9 / 18;
  background: linear-gradient(180deg, #fafafa 0%, #f0f0f2 100%);
  border-radius: 40px;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
  padding: 28px 18px;
}

.hero__phone-screen {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100%;
  gap: var(--space-md);
}

.hero__bpm {
  font-size: 88px;
  font-weight: 800;
  color: var(--color-text);
  letter-spacing: -0.04em;
  line-height: 1;
  display: flex;
  align-items: baseline;
  gap: 6px;
}

.hero__bpm-unit {
  font-size: 16px;
  font-weight: 500;
  color: var(--color-text-muted);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.hero__bpm-label {
  font-size: 13px;
  font-weight: 500;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.hero__heart {
  width: 48px;
  height: 48px;
  color: var(--color-accent);
  animation: heart-pulse 1.2s var(--ease) infinite;
}

@keyframes heart-pulse {
  0%, 100% { transform: scale(1); }
  20% { transform: scale(1.15); }
  40% { transform: scale(0.95); }
}

@media (prefers-reduced-motion: reduce) {
  .hero__heart { animation: none; }
}

/* =================== Features =================== */

.section__head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto var(--space-2xl);
}

.section__title {
  font-size: clamp(32px, 4vw, 44px);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: var(--space-md);
}

.section__subtitle {
  font-size: 18px;
  color: var(--color-text-muted);
  line-height: 1.5;
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-lg);
}

.feature {
  padding: var(--space-xl);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  transition: transform 250ms var(--ease), box-shadow 250ms var(--ease), border-color 250ms var(--ease);
}

.feature:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
  border-color: var(--color-border-strong);
}

.feature__icon {
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-md);
}

.feature__icon svg {
  width: 24px;
  height: 24px;
}

.feature__title {
  font-size: 19px;
  font-weight: 600;
  margin-bottom: var(--space-sm);
  letter-spacing: -0.01em;
}

.feature__desc {
  font-size: 15px;
  line-height: 1.55;
  color: var(--color-text-muted);
}

/* =================== How it works =================== */

.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-xl);
  counter-reset: step;
}

.step {
  text-align: center;
  counter-increment: step;
}

.step__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: var(--color-text);
  color: #fff;
  border-radius: 50%;
  font-weight: 600;
  font-size: 17px;
  margin: 0 auto var(--space-md);
}

.step__title {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: var(--space-sm);
}

.step__desc {
  font-size: 15px;
  color: var(--color-text-muted);
  line-height: 1.5;
}

/* =================== CTA =================== */

.cta {
  text-align: center;
  padding: var(--space-3xl) var(--space-lg);
  background: var(--color-text);
  color: #fff;
  border-radius: var(--radius-lg);
}

.cta__title {
  font-size: clamp(28px, 4vw, 40px);
  color: #fff;
  margin-bottom: var(--space-md);
}

.cta__subtitle {
  font-size: 17px;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: var(--space-xl);
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}

.cta .btn--primary {
  background: #fff;
  color: var(--color-text);
}

.cta .btn--primary:hover {
  background: var(--color-bg-alt);
}

/* =================== Footer =================== */

.footer {
  background: var(--color-bg-alt);
  border-top: 1px solid var(--color-border);
  padding: var(--space-2xl) 0 var(--space-lg);
  font-size: 13px;
  color: var(--color-text-muted);
}

.footer__grid {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--space-2xl);
  flex-wrap: wrap;
  padding-bottom: var(--space-xl);
  border-bottom: 1px solid var(--color-border);
}

.footer__brand {
  font-weight: 700;
  color: var(--color-text);
  font-size: 15px;
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.footer__brand svg {
  width: 22px;
  height: 22px;
  color: var(--color-accent);
}

.footer__links {
  display: flex;
  gap: var(--space-xl);
  flex-wrap: wrap;
}

.footer__link {
  color: var(--color-text-muted);
  font-size: 13px;
}

.footer__link:hover {
  color: var(--color-text);
  text-decoration: none;
}

.footer__bottom {
  padding-top: var(--space-lg);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.footer__legal {
  font-size: 12px;
  color: var(--color-text-subtle);
  max-width: 720px;
  line-height: 1.5;
}

/* =================== Legal / Content pages =================== */

.page-head {
  padding: var(--space-3xl) 0 var(--space-xl);
  border-bottom: 1px solid var(--color-border);
}

.page-head__title {
  font-size: clamp(36px, 5vw, 52px);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-bottom: var(--space-sm);
}

.page-head__meta {
  font-size: 14px;
  color: var(--color-text-subtle);
}

.prose {
  max-width: 720px;
  margin: 0 auto;
  padding: var(--space-2xl) var(--space-lg);
  font-size: 16px;
  line-height: 1.65;
  color: var(--color-text);
}

.prose h2 {
  font-size: 22px;
  font-weight: 600;
  margin-top: var(--space-2xl);
  margin-bottom: var(--space-md);
  letter-spacing: -0.015em;
}

.prose h2:first-child {
  margin-top: 0;
}

.prose h3 {
  font-size: 17px;
  font-weight: 600;
  margin-top: var(--space-xl);
  margin-bottom: var(--space-sm);
}

.prose p {
  margin-bottom: var(--space-md);
  color: var(--color-text-muted);
}

.prose ul {
  margin: 0 0 var(--space-md);
  padding-left: var(--space-lg);
  color: var(--color-text-muted);
}

.prose li {
  margin-bottom: var(--space-sm);
}

.prose strong {
  color: var(--color-text);
  font-weight: 600;
}

.prose a {
  color: var(--color-link);
  text-decoration: underline;
  text-underline-offset: 2px;
}

/* =================== Contact form =================== */

.contact {
  max-width: 560px;
  margin: 0 auto;
  padding: var(--space-2xl) var(--space-lg);
}

.contact__intro {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.contact__intro p {
  color: var(--color-text-muted);
  font-size: 17px;
  margin-top: var(--space-md);
}

.form {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.field {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.field__label {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text);
}

.field__input,
.field__textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 16px;
  color: var(--color-text);
  background: var(--color-bg);
  transition: border-color 200ms var(--ease), box-shadow 200ms var(--ease);
}

.field__input:focus,
.field__textarea:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-soft);
}

.field__textarea {
  min-height: 140px;
  resize: vertical;
  font-family: inherit;
  line-height: 1.5;
}

.contact__email {
  text-align: center;
  margin-top: var(--space-xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: 15px;
}

.contact__email a {
  color: var(--color-link);
  font-weight: 500;
}

/* =================== Responsive =================== */

@media (max-width: 720px) {
  .section { padding: var(--space-3xl) 0; }
  .hero { padding: var(--space-2xl) 0 var(--space-xl); }

  .nav__menu {
    position: fixed;
    inset: 56px 0 auto 0;
    flex-direction: column;
    gap: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-md) var(--space-lg);
    transform: translateY(-150%);
    transition: transform 300ms var(--ease);
  }

  .nav__menu[data-open="true"] {
    transform: translateY(0);
  }

  .nav__menu li {
    width: 100%;
    padding: var(--space-md) 0;
    border-bottom: 1px solid var(--color-border);
  }

  .nav__menu li:last-child {
    border-bottom: 0;
  }

  .nav__toggle {
    display: inline-flex;
  }

  .footer__grid { flex-direction: column; gap: var(--space-lg); }
  .footer__bottom { flex-direction: column; }
}