/* ==========================================================================
   Dams and Civils — styles.css
   Mobile-first CSS reset + custom properties + layout for the single-page
   marketing site. No build step / no framework (see research.md #1).
   ========================================================================== */

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

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

body,
h1,
h2,
h3,
p,
ul,
figure {
  margin: 0;
}

ul {
  list-style: none;
  padding: 0;
}

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

a {
  color: inherit;
}

button {
  font: inherit;
}

/* --- Custom properties (theme) ------------------------------------------ */
:root {
  --color-bg: #f7f6f1;
  --color-surface: #ffffff;
  --color-text: #16233a;
  --color-text-muted: #4c5c72;
  --color-primary: #1d6fae;
  --color-primary-dark: #0d2b4e;
  --color-accent: #f2994a;
  --color-border: #d8dfe8;
  --color-error: #b3261e;
  --color-success: #1d6fae;

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 1rem;
  --space-4: 1.5rem;
  --space-5: 2rem;
  --space-6: 3rem;

  --radius: 0.5rem;
  --max-width: 72rem;
  --touch-target: 44px;

  --font-base: 1rem;
  --font-scale: 1.2;
}

/* --- Base typography ------------------------------------------------------ */
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.5;
  font-size: 100%;
  overflow-x: hidden;
}

h1 {
  font-size: 1.75rem;
  line-height: 1.2;
  color: var(--color-primary-dark);
}

h2 {
  font-size: 1.5rem;
  line-height: 1.25;
  color: var(--color-primary-dark);
  margin-bottom: var(--space-4);
}

@media (min-width: 768px) {
  h1 {
    font-size: 2.5rem;
  }
  h2 {
    font-size: 2rem;
  }
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

section {
  padding: var(--space-6) var(--space-3);
  max-width: var(--max-width);
  margin: 0 auto;
}

/* --- Header / nav --------------------------------------------------------- */
.site-header {
  background-color: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 20;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-1) var(--space-3);
}

.logo {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  min-height: var(--touch-target);
}

.logo-image {
  height: 96px;
  width: auto;
}

.nav-toggle {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 4px;
  width: var(--touch-target);
  height: var(--touch-target);
  background: none;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  cursor: pointer;
}

.nav-toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  background-color: var(--color-text);
}

.primary-nav {
  display: none;
  width: 100%;
}

.primary-nav.is-open {
  display: block;
}

.primary-nav ul {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-3) 0;
}

.primary-nav .nav-link {
  display: flex;
  align-items: center;
  min-height: var(--touch-target);
  padding: var(--space-2) var(--space-3);
  text-decoration: none;
  font-weight: 600;
  color: var(--color-text);
  border-radius: var(--radius);
}

.primary-nav .nav-link:hover,
.primary-nav .nav-link:focus-visible {
  background-color: var(--color-bg);
  color: var(--color-primary);
}

@media (min-width: 768px) {
  .nav-toggle {
    display: none;
  }

  .primary-nav {
    display: block;
    width: auto;
  }

  .primary-nav ul {
    flex-direction: row;
    padding: 0;
    gap: var(--space-4);
  }
}

/* Company info bar — visible in header regardless of scroll position (FR-001) */
.company-info-bar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-4);
  padding: var(--space-2) var(--space-3);
  background-color: var(--color-primary-dark);
  color: #ffffff;
  font-size: 0.75rem;
}

.company-info-bar a {
  color: #ffffff;
  text-decoration: underline;
}

.company-info-item.company-legal-name {
  font-weight: 700;
}

@media (min-width: 768px) {
  .company-info-bar {
    font-size: 0.85rem;
    justify-content: center;
  }
}

/* --- Hero ----------------------------------------------------------------- */
.hero {
  text-align: center;
  padding-top: var(--space-6);
  padding-bottom: var(--space-6);
}

.hero-image {
  width: 100vw;
  position: relative;
  left: 50%;
  right: 50%;
  margin-left: -50vw;
  margin-right: -50vw;
  margin-top: calc(var(--space-6) * -1);
  margin-bottom: var(--space-5);
  overflow: hidden;
}

.hero-image img {
  width: 100%;
  height: 16rem;
  object-fit: cover;
}

@media (min-width: 768px) {
  .hero-image img {
    height: 22rem;
  }
}

.hero p {
  margin-top: var(--space-3);
  color: var(--color-text-muted);
  max-width: 42rem;
  margin-left: auto;
  margin-right: auto;
}

.cta-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: var(--touch-target);
  margin-top: var(--space-4);
  padding: 0 var(--space-4);
  background-color: var(--color-primary);
  color: #ffffff;
  text-decoration: none;
  border: none;
  border-radius: var(--radius);
  font-weight: 700;
  cursor: pointer;
}

.cta-button:hover,
.cta-button:focus-visible {
  background-color: var(--color-primary-dark);
}

/* --- Services grid ---------------------------------------------------------- */
.services-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-4);
}

@media (min-width: 768px) {
  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .services-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.service-card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: var(--space-4);
}

.service-card h3 {
  color: var(--color-primary-dark);
  font-size: 1.1rem;
  margin-bottom: var(--space-2);
}

.service-card p {
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* --- Projects gallery -------------------------------------------------------- */
.projects-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-4);
}

@media (min-width: 768px) {
  .projects-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .projects-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.project-card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
}

.project-card img {
  width: 100%;
  height: 12rem;
  object-fit: cover;
}

.project-card figcaption {
  padding: var(--space-3);
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

.project-card.project-card-fallback {
  padding: var(--space-4);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--color-text-muted);
  min-height: 8rem;
}

.projects-empty-state {
  text-align: center;
  color: var(--color-text-muted);
  padding: var(--space-5);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius);
  grid-column: 1 / -1;
}

/* --- Quote form ---------------------------------------------------------------- */
.quote-form {
  max-width: 40rem;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.form-row {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

@media (min-width: 768px) {
  .form-row {
    flex-direction: row;
  }

  .form-row .form-field {
    flex: 1;
  }
}

.form-field {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.form-field label {
  font-weight: 600;
}

.form-field input,
.form-field textarea {
  min-height: var(--touch-target);
  padding: var(--space-2) var(--space-3);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font: inherit;
  background-color: var(--color-surface);
  color: var(--color-text);
}

.form-field textarea {
  min-height: 8rem;
  resize: vertical;
}

.form-field input:focus-visible,
.form-field textarea:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 1px;
}

.form-field.has-error input,
.form-field.has-error textarea {
  border-color: var(--color-error);
}

.field-error {
  color: var(--color-error);
  font-size: 0.85rem;
  min-height: 1.1em;
}

.quote-submit {
  align-self: flex-start;
}

.quote-submit:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.form-status {
  font-weight: 600;
  min-height: 1.2em;
}

.form-status.is-success {
  color: var(--color-success);
}

.form-status.is-error {
  color: var(--color-error);
}

/* --- Footer ------------------------------------------------------------------ */
.site-footer {
  background-color: var(--color-primary-dark);
  color: #ffffff;
  padding: var(--space-5) var(--space-3);
  text-align: center;
  font-size: 0.9rem;
}

.site-footer p {
  margin-bottom: var(--space-1);
}

.site-footer a {
  color: #ffffff;
}

.footer-copy {
  margin-top: var(--space-3);
  opacity: 0.8;
  font-size: 0.8rem;
}