/* ============================================
   Karst — style.css
   ============================================ */

/* --- Google Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&family=Playfair+Display:wght@700&display=swap');

/* --- Custom Properties --- */
:root {
  --color-deep-slate: #1B3A4B;
  --color-stone-green: #2D5016;
  --color-limestone: #E8E0D0;
  --color-aquifer: #4A90A4;
  --color-sage-mist: #8AAF7A;
  --color-cave-shadow: #2A2A2A;
  --color-fog: #F5F2EE;
  --color-chalk: #FFFFFF;

  --font-display: 'Playfair Display', Georgia, serif;
  --font-body: 'Inter', -apple-system, sans-serif;

  --max-width: 1100px;
  --unit: 8px;
}

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

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

body {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  color: var(--color-cave-shadow);
  background-color: var(--color-fog);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

ul {
  list-style: none;
}

/* --- Typography --- */
h1 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 56px;
  line-height: 1.15;
  color: var(--color-deep-slate);
}

h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 36px;
  line-height: 1.25;
  color: var(--color-deep-slate);
}

h3 {
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 22px;
  line-height: 1.35;
  color: var(--color-deep-slate);
}

.label {
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 13px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  color: var(--color-aquifer);
}

/* --- Layout --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}

section {
  padding: 96px 0;
}

/* --- Navigation --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  transition: background-color 200ms, border-color 200ms;
  border-bottom: 1px solid transparent;
}

.nav.scrolled {
  background-color: var(--color-chalk);
  border-bottom-color: var(--color-limestone);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-wordmark {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 24px;
  color: var(--color-deep-slate);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-links a {
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 13px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  color: var(--color-deep-slate);
  transition: color 150ms;
}

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

.nav-hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--color-deep-slate);
  margin: 5px 0;
  transition: transform 200ms, opacity 200ms;
}

.nav-hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

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

.nav-hamburger.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* --- Dark nav variant (products page hero) --- */
.nav--dark .nav-wordmark,
.nav--dark .nav-links a {
  color: var(--color-chalk);
}

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

.nav--dark .nav-hamburger span {
  background-color: var(--color-chalk);
}

.nav--dark.scrolled .nav-wordmark,
.nav--dark.scrolled .nav-links a {
  color: var(--color-deep-slate);
}

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

.nav--dark.scrolled .nav-hamburger span {
  background-color: var(--color-deep-slate);
}

/* --- Buttons --- */
.btn {
  display: inline-block;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 14px;
  padding: 12px 28px;
  border-radius: 2px;
  border: none;
  cursor: pointer;
  transition: background-color 150ms;
  text-decoration: none;
}

.btn--primary {
  background-color: var(--color-deep-slate);
  color: var(--color-chalk);
}

.btn--primary:hover {
  background-color: #152f3d;
}

.btn--aquifer {
  background-color: var(--color-aquifer);
  color: var(--color-chalk);
}

.btn--aquifer:hover {
  background-color: #3d7a8c;
}

/* --- Hero (Landing) --- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  opacity: 0.06;
  pointer-events: none;
}

.hero-bg svg {
  width: 100%;
  height: 100%;
}

.hero-content {
  position: relative;
  max-width: 700px;
}

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

.hero-subhead {
  font-family: var(--font-body);
  font-weight: 400;
  font-size: 20px;
  line-height: 1.6;
  color: var(--color-cave-shadow);
  opacity: 0.7;
  margin-bottom: 40px;
  max-width: 600px;
}

/* --- Hero (Products) --- */
.hero--products {
  min-height: 50vh;
  display: flex;
  align-items: center;
  background-color: var(--color-deep-slate);
}

.hero--products h1 {
  color: var(--color-chalk);
  margin-bottom: 16px;
}

.hero--products .hero-subhead {
  color: var(--color-chalk);
  opacity: 0.75;
  margin-bottom: 0;
}

/* --- Mission Section --- */
.mission {
  text-align: center;
}

.mission-inner {
  max-width: 720px;
  margin: 0 auto;
}

.mission h2 {
  margin-bottom: 24px;
}

.mission p {
  color: var(--color-cave-shadow);
}

/* --- Values Section --- */
.values-heading {
  display: block;
  text-align: center;
  font-size: 36px;
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--color-deep-slate);
  text-transform: none;
  letter-spacing: 0;
  margin-bottom: 48px;
}

.values-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.value-card {
  background-color: var(--color-chalk);
  padding: 32px;
  border-radius: 2px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  text-align: center;
}

.value-card h3 {
  margin-bottom: 16px;
}

.value-card p {
  color: var(--color-cave-shadow);
}

/* --- Product Section (WrapUp) --- */
.product-section {
  background-color: var(--color-fog);
}

.product-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.product-text .label {
  display: block;
  margin-bottom: 16px;
}

.product-text h2 {
  margin-bottom: 24px;
}

.product-text > p {
  margin-bottom: 32px;
  color: var(--color-cave-shadow);
}

.feature-list {
  margin-bottom: 40px;
}

.feature-list li {
  padding: 12px 0 12px 20px;
  border-left: 2px solid var(--color-aquifer);
  color: var(--color-cave-shadow);
  font-size: 16px;
}

.feature-list li + li {
  margin-top: 4px;
}

/* --- Report Mockup Card --- */
.report-mockup {
  background-color: var(--color-chalk);
  border-radius: 2px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  padding: 32px;
  font-family: var(--font-body);
}

.report-mockup-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--color-limestone);
}

.report-mockup-title {
  font-weight: 600;
  font-size: 15px;
  color: var(--color-deep-slate);
}

.report-mockup-badge {
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--color-chalk);
  background-color: var(--color-aquifer);
  padding: 4px 10px;
  border-radius: 2px;
}

.report-mockup-row {
  margin-bottom: 16px;
}

.report-mockup-label {
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--color-aquifer);
  margin-bottom: 4px;
}

.report-mockup-value {
  font-size: 14px;
  color: var(--color-cave-shadow);
  line-height: 1.5;
}

.report-mockup-divider {
  height: 1px;
  background-color: var(--color-limestone);
  margin: 20px 0;
}

/* --- Coming Soon Section --- */
.coming-soon {
  background-color: var(--color-limestone);
  text-align: center;
}

.coming-soon-inner {
  max-width: 640px;
  margin: 0 auto;
}

.coming-soon .label {
  display: block;
  margin-bottom: 16px;
}

.coming-soon h2 {
  margin-bottom: 24px;
}

.coming-soon p {
  color: var(--color-cave-shadow);
}

/* --- Why Karst Section --- */
.why-karst {
  background-color: var(--color-limestone);
}

.why-karst-inner {
  max-width: 720px;
  margin: 0 auto;
}

.why-karst .label {
  display: block;
  margin-bottom: 16px;
}

.why-karst h2 {
  margin-bottom: 32px;
}

.why-karst p {
  color: var(--color-cave-shadow);
}

.why-karst p + p {
  margin-top: 20px;
}

/* --- Footer --- */
.footer {
  background-color: var(--color-deep-slate);
  color: var(--color-chalk);
  padding: 48px 0 32px;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 32px;
}

.footer-company {
  font-weight: 500;
  font-size: 15px;
}

.footer-email a {
  font-size: 14px;
  color: var(--color-chalk);
  opacity: 0.8;
  transition: opacity 150ms;
}

.footer-email a:hover {
  opacity: 1;
}

.footer-bottom {
  font-size: 13px;
  opacity: 0.5;
}

/* --- Responsive: Tablet & Mobile --- */
@media (max-width: 768px) {
  h1 {
    font-size: 36px;
  }

  h2 {
    font-size: 28px;
  }

  section {
    padding: 64px 0;
  }

  /* Nav mobile */
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    background-color: var(--color-chalk);
    padding: 16px 24px;
    gap: 0;
    border-bottom: 1px solid var(--color-limestone);
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links a {
    padding: 12px 0;
    color: var(--color-deep-slate);
  }

  .nav-hamburger {
    display: block;
  }

  /* Hero */
  .hero {
    min-height: auto;
    padding-top: 120px;
    padding-bottom: 80px;
  }

  .hero-subhead {
    font-size: 18px;
  }

  .hero--products {
    min-height: auto;
    padding-top: 120px;
    padding-bottom: 64px;
  }

  /* Values grid */
  .values-grid {
    grid-template-columns: 1fr;
  }

  /* Product grid */
  .product-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  /* Footer */
  .footer-top {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }
}