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

/* BRAND COLOR SYSTEM */
:root {
  --primary: #316d75;
  --primary-dark: #1d4348;
  --primary-light: #4c8a92;
  --accent: #f59e0b; /* Safety amber yellow */
  --accent-light: #fbbf24;
  --bg-light: #f8fafc;
  --bg-card: #ffffff;
  --text-dark: #0f1719;
  --text-light: #f1f5f9;
  --text-muted: #64748b;
  --border-color: #e2e8f0;
  --capacity-icon-size: 20px;
  --mv-title: #ffffff;
  --mv-text: #ffffff;
  --mv-bg-1: #316d75;
  --mv-bg-2: #1d4348;
  --glass-bg: rgba(255, 255, 255, 0.75);
  --glass-border: rgba(255, 255, 255, 0.4);
  --glass-shadow: rgba(31, 38, 135, 0.08);
  --transition-fast: 0.25s ease;
  --transition-normal: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 20px -2px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 10px 30px -5px rgba(29, 67, 72, 0.15);
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
}

/* RESET & CORE STYLE */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', sans-serif;
  background-color: var(--bg-light);
  color: var(--text-dark);
  line-height: 1.6;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Montserrat', sans-serif;
  font-weight: 700;
  line-height: 1.25;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition-fast);
}

ul {
  list-style: none;
}

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

/* CONTAINER UTILITIES (Enlarged for 1920x1080 screens) */
.container {
  width: 100%;
  max-width: 1600px;
  margin: 0 auto;
  padding: 0 40px;
}

.section {
  padding: 100px 0;
  position: relative;
}

.section-bg-alt {
  background-color: #f1f5f9;
}

.section-title-wrapper {
  text-align: center;
  margin-bottom: 60px;
}

.section-tag {
  font-size: 14px;
  font-weight: 700;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 2px;
  display: block;
  margin-bottom: 12px;
}

.section-title {
  font-size: 36px;
  color: var(--primary-dark);
  position: relative;
  display: inline-block;
  padding-bottom: 16px;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 2px;
}

/* BUTTONS */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 28px;
  font-weight: 600;
  font-size: 15px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition-normal);
  border: none;
  gap: 8px;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  box-shadow: 0 4px 14px rgba(49, 109, 117, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(49, 109, 117, 0.4);
}

.btn-accent {
  background: linear-gradient(135deg, var(--accent), #d97706);
  color: white;
  box-shadow: 0 4px 14px rgba(245, 158, 11, 0.3);
}

.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(245, 158, 11, 0.4);
}

.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 2px solid var(--primary);
}

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

/* HEADER & NAVBAR */
.topbar {
  background-color: var(--primary-dark);
  color: white;
  padding: 8px 0;
  font-size: 13px;
  font-weight: 500;
}

.topbar-wrapper {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.topbar-info {
  display: flex;
  gap: 24px;
}

.topbar-info span {
  display: flex;
  align-items: center;
  gap: 8px;
}

.topbar-info i {
  color: var(--accent);
}

.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
  transition: var(--transition-fast);
}

.header.scrolled {
  background-color: var(--primary-dark);
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
  box-shadow: var(--shadow-md);
}

.header.scrolled a {
  color: white;
}

.header.scrolled .logo-text {
  color: white;
}

.header.scrolled .logo-title {
  color: white;
}

.header.scrolled .logo-img {
  filter: brightness(0) invert(1);
}

.header.scrolled .nav-menu a::after {
  background-color: var(--accent);
}

.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 0;
}

.logo-wrapper {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-img {
  height: 50px;
  width: auto;
  transition: height var(--transition-fast), filter var(--transition-fast);
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-wrapper.no-text .logo-img {
  height: 75px;
}

.logo-wrapper.no-text .logo-text {
  display: none;
}

.logo-title {
  font-size: 20px;
  font-weight: 800;
  color: var(--primary-dark);
  letter-spacing: 1px;
  transition: color var(--transition-fast);
}

.logo-subtitle {
  font-size: 11px;
  color: var(--accent);
  font-weight: 600;
  letter-spacing: 0.5px;
  transition: color var(--transition-fast);
}

.nav-menu {
  display: flex;
  gap: 32px;
}

.nav-link {
  font-weight: 600;
  font-size: 14px;
  color: var(--text-dark);
  position: relative;
  padding: 8px 0;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--primary);
  transition: var(--transition-fast);
}

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

.nav-toggle {
  display: none;
  font-size: 24px;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--primary-dark);
}

/* HERO SLIDER (Auto-fade background slider) */
.hero {
  position: relative;
  min-height: 85vh;
  display: flex;
  align-items: center;
  color: white;
  overflow: hidden;
  padding: 120px 0;
}

.hero-slider {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -2;
}

.hero-slide {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-size: cover;
  background-position: center center;
  opacity: 0;
  transition: opacity 1.5s ease-in-out;
}

.hero-slide.active {
  opacity: 1;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  background: linear-gradient(135deg, rgba(15, 23, 42, 0.9) 30%, rgba(29, 67, 72, 0.7) 100%);
}

.hero-content {
  max-width: 800px;
}

.hero-badge {
  background-color: var(--accent);
  color: var(--text-dark);
  font-weight: 700;
  font-size: 12px;
  text-transform: uppercase;
  padding: 6px 14px;
  border-radius: 50px;
  display: inline-block;
  margin-bottom: 24px;
  box-shadow: 0 4px 10px rgba(245, 158, 11, 0.3);
}

.hero-title {
  font-size: 64px;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 24px;
}

.hero-title span {
  color: var(--accent);
}

.hero-desc {
  font-size: 19px;
  opacity: 0.9;
  margin-bottom: 36px;
  font-weight: 400;
}

.hero-actions {
  display: flex;
  gap: 16px;
}

/* ABOUT / HAKKIMIZDA */
.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 60px;
  align-items: flex-start;
}

.about-text h3 {
  font-size: 28px;
  color: var(--primary-dark);
  margin-bottom: 20px;
}

.about-text p {
  color: var(--text-muted);
  margin-bottom: 24px;
  font-size: 16px;
}

.capacity-card {
  background-color: var(--bg-card);
  padding: 40px;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-color);
  position: relative;
}

.capacity-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 5px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: var(--radius-md) var(--radius-md) 0 0;
}

.capacity-title {
  font-size: 22px;
  color: var(--primary-dark);
  margin-bottom: 30px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.capacity-title i {
  color: var(--accent);
}

.capacity-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.capacity-item {
  display: flex;
  flex-direction: column;
  border-bottom: 1px dashed var(--border-color);
  padding-bottom: 12px;
}

.capacity-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.capacity-main-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.capacity-label {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 600;
}

.capacity-label i {
  color: var(--primary);
  width: calc(var(--capacity-icon-size) + 4px);
  font-size: var(--capacity-icon-size);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.capacity-val {
  font-weight: 700;
  color: var(--primary-dark);
  font-size: 18px;
}

/* NESTED CAPACITY DETAILS STYLE */
.cap-sub-list {
  margin-top: 8px;
  padding-left: 32px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.cap-sub-item-text {
  font-size: 13px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 500;
}

.cap-sub-item-text i {
  font-size: 6px;
  color: var(--accent);
}

.capacity-highlight {
  background-color: #ecf3f4;
  padding: 16px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  gap: 16px;
  margin-top: 24px;
  border-left: 4px solid var(--primary);
}

.capacity-highlight-val {
  font-size: 24px;
  font-weight: 800;
  color: var(--primary-dark);
  white-space: nowrap;
}

.capacity-highlight-desc {
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 500;
}

/* MISSION & VISION BOXES */
.mission-vision-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 30px;
  margin-top: 50px;
}

.mv-box {
  padding: 40px;
  border-radius: var(--radius-md);
  color: var(--mv-text);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.mv-box-1 {
  background: var(--mv-bg-1);
}

.mv-box-2 {
  background: var(--mv-bg-2);
}

.mv-box i {
  font-size: 40px;
  color: var(--accent);
  opacity: 0.8;
  margin-bottom: 20px;
  display: block;
}

.mv-box h4 {
  font-size: 24px;
  margin-bottom: 16px;
  color: var(--mv-title) !important;
}

.mv-box p {
  font-size: 15px;
  opacity: 0.95;
  line-height: 1.6;
  color: var(--mv-text) !important;
}

/* PRODUCTS / ÜRÜN VE HİZMETLER */
.products-desc {
  max-width: 1000px;
  margin: -40px auto 50px auto;
  text-align: center;
  color: var(--text-muted);
  font-size: 17px;
}

.products-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 30px;
}

.product-card {
  background-color: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 30px;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  transition: var(--transition-normal);
  display: flex;
  flex-direction: column;
  position: relative;
}

.product-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.product-badge {
  background-color: var(--primary);
  color: white;
  font-weight: 800;
  font-size: 18px;
  width: 80px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
  font-family: 'Montserrat', sans-serif;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
}

.product-title {
  font-size: 18px;
  color: var(--primary-dark);
  margin-bottom: 12px;
}

.product-desc {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 20px;
  flex-grow: 1;
}

.product-details {
  border-top: 1px solid var(--border-color);
  padding-top: 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 13px;
}

.detail-row {
  display: flex;
  justify-content: space-between;
}

.detail-label {
  color: var(--text-muted);
  font-weight: 500;
}

.detail-val {
  font-weight: 600;
  color: var(--text-dark);
}

/* CONCRETE & STEEL CALCULATORS DUAL GRID */
.calculators-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}

@media (max-width: 1280px) {
  .calculators-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
}

.calc-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  background-color: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-color);
  overflow: hidden;
}

.calc-form-panel {
  padding: 30px 35px;
}

.calc-result-panel {
  background: linear-gradient(135deg, var(--primary-dark), #0f2427);
  color: white;
  padding: 30px 35px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  position: relative;
}

.calc-result-panel::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0.05;
  background: radial-gradient(circle, var(--accent) 10%, transparent 11%);
  background-size: 16px 16px;
}

.calc-group {
  margin-bottom: 24px;
}

.calc-group label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text-dark);
}

.calc-input {
  width: 100%;
  padding: 14px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 15px;
  outline: none;
  transition: var(--transition-fast);
}

.calc-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(49, 109, 117, 0.15);
}

.calc-select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%2364748b'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  background-size: 16px;
}

.calc-result-title {
  font-size: 18px;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 20px;
  font-weight: 700;
}

.calc-result-box {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 30px;
}

.calc-result-value {
  font-size: 56px;
  font-weight: 800;
  font-family: 'Montserrat', sans-serif;
  color: white;
  line-height: 1;
}

.calc-result-unit {
  font-size: 24px;
  font-weight: 600;
  color: rgba(255,255,255,0.7);
}

.calc-info-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.calc-info-card {
  background-color: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 20px;
  border-radius: var(--radius-sm);
}

.calc-info-icon {
  font-size: 24px;
  color: var(--accent);
  margin-bottom: 12px;
}

.calc-info-num {
  font-size: 20px;
  font-weight: 700;
  color: white;
}

.calc-info-label {
  font-size: 12px;
  color: rgba(255,255,255,0.6);
  margin-top: 4px;
}

.calc-disclaimer {
  margin-top: 30px;
  font-size: 12px;
  color: rgba(255, 255, 255, 0.5);
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.calc-disclaimer i {
  margin-top: 2px;
}

.btn-sync {
  transition: background-color var(--transition-fast);
}

.btn-sync:hover {
  background-color: var(--primary-dark) !important;
}

/* TECHNICAL INFO (ACCORDION) */
.tech-container {
  width: 100%;
}

.accordion-item {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition-fast);
}

.accordion-item:hover {
  border-color: var(--primary-light);
  box-shadow: var(--shadow-md);
}

.accordion-header {
  width: 100%;
  padding: 24px 30px;
  background: none;
  border: none;
  text-align: left;
  font-family: inherit;
  font-size: 17px;
  font-weight: 700;
  color: var(--primary-dark);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
}

.accordion-icon {
  font-size: 16px;
  color: var(--primary);
  transition: transform var(--transition-fast);
}

.accordion-item.active .accordion-icon {
  transform: rotate(180deg);
}

.accordion-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-normal);
  background-color: #fcfdfe;
}

.accordion-content-inner {
  padding: 0 30px 30px 30px;
  font-size: 15px;
  color: var(--text-muted);
}

.accordion-content-inner strong {
  color: var(--text-dark);
  display: inline;
}

.accordion-content-inner ul {
  margin-top: 10px;
}

/* Fixed Vertical Alignment for List Bullet Items */
.accordion-content-inner li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-bottom: 8px;
  line-height: 1.6;
}

.accordion-content-inner li i {
  color: var(--accent);
  font-size: 10px;
  margin-top: 6px; /* Lower dot slightly to sit level with text middle line */
  flex-shrink: 0;
}

/* REFERENCES (3-Column Desktop Grid with enlarged images) */
.portfolio-filter {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 40px;
}

.filter-btn {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 10px 20px;
  border-radius: 50px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-fast);
  color: var(--text-muted);
}

.filter-btn:hover,
.filter-btn.active {
  background-color: var(--primary);
  border-color: var(--primary);
  color: white;
}

.references-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr)); /* Enlarged items sizing */
  gap: 35px;
}

@media (min-width: 1024px) {
  .references-grid {
    grid-template-columns: repeat(3, 1fr); /* Exactly 3 items per row on desktop */
  }
}

.reference-card {
  background-color: var(--bg-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
  transition: var(--transition-normal);
  opacity: 1;
}

.reference-card.hidden {
  display: none;
}

.reference-img-wrapper {
  position: relative;
  overflow: hidden;
  height: 250px; /* Enlarged reference card image height */
  background-color: #e2e8f0;
}

/* Generic mock image styling inside references */
.reference-img-wrapper::after {
  content: '\f1ad';
  font-family: 'FontAwesome';
  font-size: 48px;
  color: rgba(49, 109, 117, 0.15);
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.reference-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: var(--transition-normal);
}

.reference-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
}

.reference-card:hover img {
  transform: scale(1.06);
}

.reference-info {
  padding: 24px;
}

.reference-category {
  font-size: 11px;
  font-weight: 700;
  color: var(--accent);
  text-transform: uppercase;
  margin-bottom: 8px;
  display: block;
}

.reference-title {
  font-size: 18px;
  color: var(--primary-dark);
  margin-bottom: 8px;
}

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

/* CONTACT, MAP, & FORM LAYOUT RE-POSITIONING */
.contact-container {
  display: flex;
  flex-direction: column;
  gap: 50px;
}

.contact-upper-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 60px;
  align-items: stretch;
}

.contact-info-panel h3 {
  font-size: 26px;
  color: var(--primary-dark);
  margin-bottom: 24px;
}

.contact-links {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.contact-link-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.contact-link-icon {
  background-color: rgba(49, 109, 117, 0.1);
  color: var(--primary);
  width: 44px;
  height: 44px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  flex-shrink: 0;
}

.contact-link-details strong {
  display: block;
  font-size: 14px;
  color: var(--text-dark);
  margin-bottom: 4px;
}

.contact-link-details p,
.contact-link-details a {
  font-size: 15px;
  color: var(--text-muted);
}

.contact-link-details a:hover {
  color: var(--primary);
}

/* Inline map styling */
.contact-map-wrapper {
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-color);
  height: 100%;
  min-height: 350px;
  box-shadow: var(--shadow-sm);
}

.contact-map-wrapper iframe {
  width: 100%;
  height: 100%;
  border: none;
}

/* Form below, occupying full width or styled centered */
.contact-lower-form {
  width: 100%;
}

.contact-form-card {
  background-color: var(--bg-card);
  padding: 40px;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-color);
}

.contact-form-title {
  font-size: 22px;
  color: var(--primary-dark);
  margin-bottom: 30px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 20px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-dark);
}

.form-input {
  width: 100%;
  padding: 12px;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  outline: none;
  font-family: inherit;
  font-size: 14px;
  transition: var(--transition-fast);
}

.form-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(49, 109, 117, 0.15);
}

textarea.form-input {
  resize: vertical;
}

/* FOOTER */
.footer {
  background-color: #111a1c;
  color: #94a3b8;
  padding: 80px 0 20px 0;
  border-top: 5px solid var(--primary-dark);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1.5fr;
  gap: 50px;
  margin-bottom: 50px;
}

.footer-widget h4 {
  color: white;
  font-size: 18px;
  margin-bottom: 24px;
  position: relative;
  padding-bottom: 10px;
}

.footer-widget h4::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 40px;
  height: 2px;
  background-color: var(--accent);
}

.footer-widget p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 20px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.footer-logo img {
  height: 40px;
  background-color: white;
  padding: 4px;
  border-radius: 4px;
}

.footer-logo-title {
  color: white;
  font-weight: 800;
  font-size: 18px;
  font-family: 'Montserrat', sans-serif;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-links a {
  font-size: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.footer-links a:hover {
  color: white;
  transform: translateX(4px);
}

.footer-links i {
  font-size: 12px;
  color: var(--accent);
}

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

.footer-contact-item {
  display: flex;
  gap: 12px;
  font-size: 14px;
}

.footer-contact-item i {
  color: var(--accent);
  margin-top: 4px;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 13px;
}

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

.footer-bottom-links a:hover {
  color: white;
}

/* BACK TO TOP BUTTON */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: -60px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background-color: var(--primary);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  cursor: pointer;
  box-shadow: 0 4px 10px rgba(0,0,0,0.15);
  z-index: 999;
  transition: var(--transition-normal);
}

.back-to-top.show {
  right: 30px;
}

.back-to-top:hover {
  background-color: var(--accent);
  transform: translateY(-4px);
}

/* ALERT NOTIFICATIONS */
.alert-popup {
  position: fixed;
  bottom: 30px;
  left: 30px;
  background-color: var(--primary-dark);
  color: white;
  padding: 16px 24px;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-lg);
  z-index: 9999;
  transform: translateY(150%);
  transition: var(--transition-normal);
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 500;
  border-left: 5px solid var(--accent);
}

.alert-popup.show {
  transform: translateY(0);
}

/* MEDIA QUERIES (RESPONSIVE) */
@media (max-width: 1280px) {
  .references-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 1024px) {
  .hero-title {
    font-size: 48px;
  }
  .about-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .calc-container {
    grid-template-columns: 1fr;
  }
  .contact-upper-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0 24px;
  }
  .header .container {
    padding-left: 20px;
    padding-right: 20px;
  }
  body {
    font-size: 14px;
  }
  .section-title {
    font-size: 28px;
  }
  .topbar {
    display: none;
  }
  .navbar {
    padding: 12px 0;
  }
  .nav-menu {
    position: fixed;
    top: 80px;
    left: -100%;
    width: 100%;
    height: calc(100vh - 80px);
    background-color: white;
    flex-direction: column;
    padding: 40px 24px;
    gap: 24px;
    transition: var(--transition-normal);
    box-shadow: var(--shadow-lg);
  }
  .nav-menu.active {
    left: 0;
  }
  .nav-toggle {
    display: block;
  }
  .nav-link {
    font-size: 15px;
  }
  .header.scrolled .nav-toggle {
    color: white;
  }
  .header.scrolled .nav-menu {
    background-color: rgba(29, 67, 72, 0.98);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: var(--shadow-lg);
  }
  .header.scrolled .nav-menu .nav-link {
    color: white;
  }
  .hero {
    min-height: auto;
    padding: 100px 0 80px 0;
  }
  .hero-title {
    font-size: 32px;
  }
  .hero-desc {
    font-size: 15px;
  }
  .hero-actions {
    flex-direction: column;
  }
  .about-text h3 {
    font-size: 22px;
  }
  .capacity-val {
    font-size: 16px;
  }
  .mission-vision-grid {
    grid-template-columns: 1fr;
  }
  .calc-form-panel, .calc-result-panel {
    padding: 30px;
  }
  .calc-result-value {
    font-size: 44px;
  }
  .form-row {
    grid-template-columns: 1fr;
    gap: 0;
  }
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
}