* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: #f8f6f1;
  color: #111111;
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.5;
}

a {
  color: inherit;
}

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


/* =========================
   NAVIGATION
========================= */

.nav {
  min-height: 68px;
  padding: 16px 7%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;

  background: rgba(248, 246, 241, 0.96);
  border-bottom: 1px solid #e5e0d8;

  position: sticky;
  top: 0;
  z-index: 20;
}

.nav .brand {
  font-size: 18px;
  font-weight: 800;
  text-decoration: none;
}

.nav nav {
  display: flex;
  align-items: center;
  gap: 22px;
}

.nav nav > a:not(.button) {
  text-decoration: none;
  font-size: 14px;
}

.nav nav > a:not(.button):hover {
  text-decoration: underline;
}


/* =========================
   TYPOGRAPHY
========================= */

h1,
h2,
h3,
h4,
p {
  margin-top: 0;
}

h1 {
  max-width: 760px;
  margin-bottom: 24px;
  font-size: clamp(52px, 7vw, 92px);
  line-height: 0.98;
  letter-spacing: -0.055em;
}

h2 {
  margin-bottom: 14px;
  font-size: clamp(34px, 4vw, 54px);
  line-height: 1.02;
  letter-spacing: -0.04em;
}

h3 {
  font-size: 20px;
  line-height: 1.2;
}

h4 {
  font-size: 16px;
}

.eyebrow {
  margin-bottom: 10px;
  color: #68415f;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.lead {
  max-width: 680px;
  margin-bottom: 30px;
  color: #5f5b56;
  font-size: 18px;
}

.muted {
  color: #716c66;
}


/* =========================
   BUTTONS
========================= */

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;

  min-height: 44px;
  padding: 11px 20px;

  border: 1px solid #111111;
  border-radius: 999px;

  background: #111111;
  color: #ffffff;

  font-size: 14px;
  font-weight: 700;
  text-decoration: none;

  cursor: pointer;
}

.button:hover {
  opacity: 0.86;
}

.button.secondary {
  background: transparent;
  color: #111111;
}

.button.small {
  min-height: 36px;
  padding: 8px 15px;
  font-size: 12px;
}


/* =========================
   HERO
========================= */

.hero {
  min-height: 620px;
  padding: 110px 8% 70px;

  display: flex;
  flex-direction: column;
  justify-content: center;

  border-bottom: 1px solid #e5e0d8;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 25px;
}

.trust {
  max-width: 720px;
  color: #77716a;
  font-size: 12px;
}


/* =========================
   SECTIONS
========================= */

.section {
  padding: 80px 8%;
}

.section.alt {
  background: #f0ece4;
}

.section-head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 30px;

  margin-bottom: 28px;
}

.section-head > div {
  max-width: 760px;
}

.section-head p {
  margin-bottom: 0;
  color: #68635d;
}

.notice {
  margin-bottom: 20px;
  color: #716c66;
  font-size: 14px;
}


/* =========================
   HAIR LIBRARY
========================= */

.library-search {
  margin: 28px 0 18px;
}

.library-search input {
  width: 100%;
  max-width: 720px;

  padding: 17px 19px;

  border: 1px solid #d5d0c9;
  border-radius: 14px;

  background: #ffffff;

  font-size: 16px;
}

.library-search input:focus {
  outline: 2px solid #111111;
  outline-offset: 2px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.card {
  background: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 16px;

  padding: 24px;

  box-shadow: 0 8px 24px rgba(20, 18, 15, 0.035);
}

.library-card {
  min-height: 245px;

  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.library-card h3 {
  margin-top: 4px;
  margin-bottom: 10px;
}

.library-card .muted {
  font-size: 14px;
}

.evidence-count {
  margin-top: auto;
  padding-top: 22px;
  margin-bottom: 14px;
}

.product-evidence {
  width: 100%;

  margin-top: 22px;
  padding-top: 20px;

  border-top: 1px solid #e6e1da;
}

.product-evidence h4 {
  margin: 20px 0 8px;
}

.resource {
  width: 100%;

  padding: 17px 0;

  border-top: 1px solid #ece8e2;
}

.resource:first-of-type {
  border-top: 0;
}

.resource strong {
  display: block;
  margin-bottom: 6px;
  line-height: 1.35;
}

.resource p {
  margin: 5px 0 8px;
  font-size: 13px;
}

.resource a {
  color: #4e3150;
  font-size: 13px;
  font-weight: 700;
}


/* =========================
   FORMS
========================= */

.form-wrap {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(420px, 1.2fr);
  gap: 65px;
  align-items: start;
}

.form-wrap > div:first-child {
  max-width: 520px;
}

.form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.form label {
  display: flex;
  flex-direction: column;
  gap: 7px;

  font-size: 13px;
  font-weight: 700;
}

.form input,
.form select,
.form textarea {
  width: 100%;

  padding: 13px 14px;

  border: 1px solid #d9d4cc;
  border-radius: 9px;

  background: #ffffff;
  color: #111111;

  font-weight: 400;
}

.form textarea {
  resize: vertical;
}

.form input:focus,
.form select:focus,
.form textarea:focus {
  outline: 2px solid #111111;
  outline-offset: 1px;
}

.two {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.three {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.form .button {
  width: 100%;
  margin-top: 4px;
}

.form-message {
  min-height: 20px;
  font-size: 13px;
}

.form-message.success {
  color: #246331;
}

.form-message.error {
  color: #9e2f2f;
}


/* =========================
   FOOTER
========================= */

footer {
  padding: 38px 8%;

  border-top: 1px solid #e5e0d8;

  color: #77716a;
  font-size: 12px;
}


/* =========================
   TABLET
========================= */

@media (max-width: 950px) {

  .grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .form-wrap {
    grid-template-columns: 1fr;
    gap: 32px;
  }

}


/* =========================
   MOBILE
========================= */

@media (max-width: 700px) {

  .nav {
    padding: 14px 5%;
  }

  .nav nav {
    gap: 10px;
  }

  .nav nav > a:not(.button) {
    display: none;
  }

  .hero {
    min-height: auto;
    padding: 80px 6% 60px;
  }

  h1 {
    font-size: 52px;
  }

  .section {
    padding: 60px 6%;
  }

  .section-head {
    align-items: flex-start;
    flex-direction: column;
  }

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

  .library-search input {
    max-width: none;
  }

  .two,
  .three {
    grid-template-columns: 1fr;
  }

  .form-wrap {
    grid-template-columns: 1fr;
  }

  .card {
    padding: 20px;
  }

}
/* =========================
   PRODUCT PAGE
========================= */

.product-page {
  min-height: 100vh;
}

.product-hero {
  padding: 80px 8% 65px;
  border-bottom: 1px solid #e5e0d8;
}

.product-hero h1 {
  max-width: 850px;
  margin-bottom: 20px;
  font-size: clamp(44px, 6vw, 76px);
}

.product-description {
  max-width: 720px;
  color: #5f5b56;
  font-size: 17px;
}

.back-link {
  display: inline-block;
  margin-bottom: 42px;
  color: #5e5953;
  font-size: 13px;
  font-weight: 700;
  text-decoration: none;
}

.back-link:hover {
  text-decoration: underline;
}

.evidence-summary {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.summary-card {
  padding: 26px;
  background: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 16px;
}

.summary-number {
  margin-bottom: 5px;
  font-size: 38px;
  font-weight: 800;
  letter-spacing: -0.04em;
}

.evidence-list {
  display: grid;
  gap: 16px;
  max-width: 900px;
}

.evidence-item {
  padding: 26px;
  background: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 16px;
}

.evidence-item h3 {
  margin-bottom: 8px;
}

.wear-card {
  max-width: 800px;
  margin-bottom: 16px;
}

.empty-state {
  max-width: 760px;
  padding: 35px;
  background: #ffffff;
  border: 1px solid #e2ddd5;
  border-radius: 16px;
}

.empty-state p {
  max-width: 600px;
  color: #66615b;
  margin-bottom: 22px;
}

@media (max-width: 700px) {

  .product-hero {
    padding: 60px 6% 45px;
  }

  .product-hero h1 {
    font-size: 44px;
  }

  .evidence-summary {
    grid-template-columns: 1fr;
  }

}