/* ============================================================
   PeptidePen Co. — Design System
   ============================================================ */

:root {
  --navy:        #0ea5e9;
  --royal:       #0284c7;
  --cyan:        #38bdf8;
  --offwhite:    #040d1a;
  --light-gray:  #081224;
  --gray:        #7a9bb8;
  --charcoal:    #e8f0fe;
  --silver:      rgba(14,165,233,0.15);

  --gradient-brand:        linear-gradient(90deg, #0ea5e9 0%, #38bdf8 100%);
  --gradient-hero-overlay: linear-gradient(135deg, rgba(14,165,233,0.08) 0%, rgba(56,189,248,0.04) 100%);

  --font-display: 'Montserrat', sans-serif;
  --font-body:    'Inter', sans-serif;
  --font-mono:    'Space Mono', monospace;

  --section-padding:    clamp(64px, 8vw, 112px);
  --container-max:      1200px;
  --container-padding:  clamp(20px, 5vw, 60px);

  --transition-fast:   180ms ease;
  --transition-smooth: 220ms cubic-bezier(0.4, 0, 0.2, 1);

  --shadow-card:       0 4px 24px rgba(0,0,0,0.3), 0 1px 4px rgba(14,165,233,0.08);
  --shadow-card-hover: 0 8px 40px rgba(0,0,0,0.4), 0 2px 8px rgba(14,165,233,0.15);
}

/* ============================================================
   Reset & Base
   ============================================================ */

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--charcoal);
  background-color: var(--offwhite);
}

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

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

/* ============================================================
   Typography
   ============================================================ */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--charcoal);
}

h1 { font-size: clamp(42px, 6vw, 64px); }
h2 { font-size: clamp(28px, 4vw, 40px); }
h3 { font-size: clamp(18px, 2.5vw, 24px); }

p {
  line-height: 1.75;
  color: var(--charcoal);
}

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

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

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 13px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  padding: 14px 32px;
  border-radius: 4px;
  border: none;
  cursor: pointer;
  transition: background var(--transition-smooth),
              color var(--transition-smooth),
              box-shadow var(--transition-smooth),
              transform var(--transition-smooth),
              opacity var(--transition-smooth);
  white-space: nowrap;
  text-decoration: none;
}

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

.btn-primary:hover {
  background: var(--royal);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(11,57,72,0.28);
}

.btn-outline {
  background: transparent;
  color: var(--navy);
  border: 1.5px solid rgba(14,165,233,0.5);
}

.btn-outline:hover {
  background: rgba(14,165,233,0.1);
  border-color: var(--navy);
  transform: translateY(-1px);
}

.btn-gradient {
  background: var(--gradient-brand);
  color: #fff;
}

.btn-gradient:hover {
  opacity: 0.88;
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(61,191,184,0.32);
}

/* ============================================================
   Navigation
   ============================================================ */

.nav {
  position: relative;
  z-index: 100;
  padding: 8px 0;
  transition: padding 300ms ease,
              background 300ms ease,
              border-color 300ms ease,
              box-shadow 300ms ease;
}

.nav.scrolled {
  padding: 8px 0;
  background: rgba(4,13,26,0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(14,165,233,0.12);
  box-shadow: 0 2px 24px rgba(0,0,0,0.4);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
}

.nav-logo {
  font-family: var(--font-display);
  font-weight: 600;
  font-style: italic;
  font-size: 20px;
  color: var(--navy);
  text-decoration: none;
  flex-shrink: 0;
  transition: opacity var(--transition-fast);
}

.nav-logo:hover {
  opacity: 0.8;
}

.nav-logo .logo-accent {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-logo img {
  height: 400px;
  width: auto;
  display: block;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 36px;
  list-style: none;
  margin-left: auto;
}

.nav-links a {
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: rgba(232,240,254,0.6);
  transition: color var(--transition-fast);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -3px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-brand);
  transition: width var(--transition-smooth);
}

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

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-cta {
  flex-shrink: 0;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
  background: none;
  border: none;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--navy);
  transition: all var(--transition-smooth);
}

/* Hamburger → X animation */
.nav-toggle.open span:nth-child(1) {
  transform: translateY(6.5px) rotate(45deg);
}

.nav-toggle.open span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.nav-toggle.open span:nth-child(3) {
  transform: translateY(-6.5px) rotate(-45deg);
}

/* Mobile slide-down panel */
.nav-mobile-panel {
  display: none;
  flex-direction: column;
  padding: 8px 0 20px;
  border-top: 1px solid rgba(199,205,209,0.3);
  margin-top: 12px;
}

.nav-mobile-panel.open {
  display: flex;
}

.nav-mobile-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  margin-bottom: 16px;
}

.nav-mobile-links a {
  display: block;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: rgba(232,240,254,0.6);
  padding: 14px 0;
  border-bottom: 1px solid rgba(14,165,233,0.1);
  transition: color var(--transition-fast);
}

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

.btn-full {
  width: 100%;
}

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

.hero {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: stretch;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gradient-hero-overlay);
  pointer-events: none;
  z-index: 0;
}

.hero-content {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: var(--section-padding) var(--container-padding);
  padding-right: 48px;
  max-width: 640px;
  margin-left: auto;
  position: relative;
  z-index: 1;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 400;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--navy);
  margin-bottom: 22px;
}

.hero-eyebrow::before {
  content: '';
  display: block;
  width: 28px;
  height: 2px;
  background: var(--gradient-brand);
  flex-shrink: 0;
}

.hero h1 {
  margin-bottom: 24px;
}

.hero h1 em {
  font-style: normal;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 17px;
  color: var(--gray);
  margin-bottom: 40px;
  max-width: 480px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

.hero-visual {
  position: relative;
  background: transparent;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  min-height: 100vh;
}

.hero-visual::after {
  content: none;
}

.hero-placeholder {
  position: relative;
  z-index: 1;
  text-align: center;
  color: rgba(255,255,255,0.4);
  font-family: var(--font-display);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.ph-tall {
  width: 220px;
  height: 360px;
  border: 1.5px dashed rgba(255,255,255,0.2);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  background: rgba(255,255,255,0.06);
}

/* ============================================================
   Section Utilities
   ============================================================ */

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

.section-header {
  margin-bottom: clamp(40px, 6vw, 64px);
}

.section-header.centered {
  text-align: center;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.section-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 400;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--navy);
  margin-bottom: 16px;
}

.section-eyebrow::before {
  content: '';
  display: block;
  width: 20px;
  height: 2px;
  background: var(--gradient-brand);
  flex-shrink: 0;
}

.centered .section-eyebrow,
.section-eyebrow.centered {
  justify-content: center;
}

.centered .section-eyebrow::before,
.section-eyebrow.centered::before {
  display: none;
}

.section-desc {
  font-size: 17px;
  color: var(--gray);
  margin-top: 14px;
  line-height: 1.8;
}

/* ============================================================
   Product Showcase (Homepage)
   ============================================================ */

.product-showcase {
  background: var(--light-gray);
}

.product-card-featured {
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: var(--light-gray);
  border: 1px solid rgba(14,165,233,0.15);
  border-radius: 4px;
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition-smooth), border-color var(--transition-smooth);
}

.product-card-featured:hover {
  box-shadow: var(--shadow-card-hover);
  border-color: rgba(14,165,233,0.35);
}

.pf-image {
  background: var(--light-gray);
  min-height: 500px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

.pf-image::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(11,57,72,0.06) 0%, rgba(61,191,184,0.1) 100%);
}

.ph-product {
  position: relative;
  z-index: 1;
  text-align: center;
  color: var(--gray);
  font-family: var(--font-display);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.ph-product-box {
  width: 150px;
  height: 250px;
  border: 1.5px dashed var(--silver);
  border-radius: 8px;
  margin: 0 auto 14px;
  background: rgba(255,255,255,0.6);
}

.pf-body {
  padding: clamp(40px, 5vw, 72px);
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.product-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: 400;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--navy);
  background: rgba(14,165,233,0.1);
  border: 1px solid rgba(14,165,233,0.2);
  padding: 4px 12px;
  border-radius: 2px;
  margin-bottom: 20px;
}

.pf-body h2 {
  font-size: clamp(24px, 3vw, 36px);
  margin-bottom: 16px;
}

.pf-body p {
  color: var(--gray);
  margin-bottom: 28px;
  font-size: 15px;
  line-height: 1.8;
}

.product-price {
  font-family: var(--font-display);
  font-size: 30px;
  font-weight: 600;
  color: var(--navy);
  letter-spacing: -0.03em;
  margin-bottom: 32px;
}

.product-price sub {
  font-size: 14px;
  font-weight: 400;
  color: var(--gray);
  letter-spacing: 0;
  vertical-align: baseline;
}

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

.cta-band {
  background: var(--navy);
  padding: var(--section-padding) 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-band::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(11,57,72,0.5) 0%, rgba(61,191,184,0.25) 100%);
}

.cta-band .container {
  position: relative;
  z-index: 1;
}

.cta-band h2 {
  color: #fff;
  margin-bottom: 16px;
}

.cta-band .section-desc {
  color: rgba(255,255,255,0.6);
  max-width: 520px;
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 40px;
}

.cta-band .section-eyebrow {
  color: var(--cyan);
}

/* ============================================================
   Page Hero (inner pages)
   ============================================================ */

.page-hero {
  padding: var(--section-padding) var(--container-padding);
  background: var(--navy);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(11,57,72,0.45) 0%, rgba(61,191,184,0.22) 100%);
}

.page-hero .container {
  position: relative;
  z-index: 1;
}

.page-hero h1 {
  color: #fff;
  margin-bottom: 16px;
}

.page-hero p {
  color: rgba(255,255,255,0.65);
  font-size: 18px;
  max-width: 520px;
  margin: 0 auto;
}

/* ============================================================
   How It Works — Steps
   ============================================================ */

.steps-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.step-card {
  background: var(--light-gray);
  border: 1px solid rgba(14,165,233,0.12);
  border-radius: 4px;
  padding: 44px 36px;
  box-shadow: var(--shadow-card);
  position: relative;
  transition: box-shadow var(--transition-smooth),
              transform var(--transition-smooth);
}

.step-card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-4px);
}

.step-number {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--navy);
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.step-number::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--light-gray);
}

.step-card h3 {
  margin-bottom: 12px;
}

.step-card p {
  color: var(--gray);
  font-size: 15px;
  line-height: 1.8;
}

/* ============================================================
   Store — Product Grid
   ============================================================ */

.products-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.product-card {
  background: var(--light-gray);
  border: 1px solid rgba(14,165,233,0.12);
  border-radius: 4px;
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition-smooth),
              transform var(--transition-smooth);
  display: flex;
  flex-direction: column;
}

.product-card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-4px);
}

.product-thumb {
  height: 280px;
  background: var(--light-gray);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
}

.product-thumb::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(11,57,72,0.05) 0%, rgba(61,191,184,0.08) 100%);
}

.ph-sm {
  width: 90px;
  height: 150px;
  border: 1.5px dashed var(--silver);
  border-radius: 6px;
  background: rgba(255,255,255,0.6);
  position: relative;
  z-index: 1;
}

.product-info {
  padding: 28px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.product-info h3 {
  font-size: 18px;
  margin-top: 10px;
  margin-bottom: 10px;
}

.product-info p {
  color: var(--gray);
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 24px;
  flex: 1;
}

.product-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: auto;
}

.pc-price {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 600;
  color: var(--navy);
  letter-spacing: -0.02em;
}

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

.footer {
  background: #040d1a;
  border-top: 1px solid rgba(14,165,233,0.12);
  color: rgba(232,240,254,0.5);
}

.footer-top {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 48px;
  padding: 64px 0 48px;
  border-bottom: 1px solid rgba(14,165,233,0.1);
}

.footer-brand .nav-logo {
  color: var(--navy);
  font-size: 20px;
  display: inline-block;
  margin-bottom: 16px;
}

.footer-brand p {
  color: rgba(255,255,255,0.5);
  font-size: 14px;
  line-height: 1.8;
  max-width: 280px;
}

.footer-col h4 {
  font-family: var(--font-display);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.35);
  margin-bottom: 20px;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-col ul a {
  font-size: 14px;
  color: rgba(255,255,255,0.6);
  transition: color var(--transition-fast);
}

.footer-col ul a:hover {
  color: var(--cyan);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 24px 0;
}

.footer-bottom p {
  font-size: 13px;
  color: rgba(255,255,255,0.3);
}

.footer-legal {
  display: flex;
  gap: 24px;
}

.footer-legal a {
  font-size: 13px;
  color: rgba(255,255,255,0.3);
  transition: color var(--transition-fast);
}

.footer-legal a:hover {
  color: rgba(255,255,255,0.6);
}

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

@media (max-width: 960px) {
  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .hero-content {
    padding: calc(80px + 48px) var(--container-padding) 40px;
    max-width: 100%;
    margin: 0;
    padding-right: var(--container-padding);
  }

  .hero-visual {
    min-height: 360px;
  }

  .product-card-featured {
    grid-template-columns: 1fr;
  }

  .pf-image {
    min-height: 320px;
  }

  .footer-top {
    grid-template-columns: 1fr 1fr;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }

  .steps-grid {
    grid-template-columns: 1fr;
    max-width: 560px;
    margin: 0 auto;
  }

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

@media (max-width: 600px) {
  .nav-links,
  .nav-cta {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

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

  .footer-top {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }

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