:root {
  --blue-dark: #0b1f4d;
  --blue-main: #102f75;
  --yellow: #f6c400;
  --yellow-dark: #dba800;
  --white: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;
  --light-bg: #f5f7fb;
  --border: #e5e7eb;
  --shadow: 0 12px 35px rgba(0, 0, 0, 0.12);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: Arial, Helvetica, sans-serif;
  color: var(--text);
  background: var(--white);
  line-height: 1.6;
}

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

a {
  text-decoration: none;
}

.container {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
}

.section-padding {
  padding: 80px 0;
}

.top-header {
  position: sticky;
  top: 0;
  z-index: 999;
  background: var(--white);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.header-inner {
  height: 82px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.logo-box {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--blue-dark);
}

.logo-box img {
  width: 58px;
  height: 58px;
  object-fit: contain;
  border-radius: 8px;
}

.logo-box strong {
  display: block;
  font-size: 18px;
  text-transform: uppercase;
  line-height: 1.2;
}

.logo-box span {
  display: block;
  color: var(--muted);
  font-size: 13px;
}

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

.main-nav a {
  color: var(--text);
  font-weight: 600;
  font-size: 15px;
  transition: 0.25s;
}

.main-nav a:hover {
  color: var(--yellow-dark);
}

.header-hotline {
  padding: 8px 14px;
  background: var(--blue-dark);
  border-radius: 999px;
  color: var(--white);
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.header-hotline span {
  font-size: 12px;
  opacity: 0.85;
}

.header-hotline a {
  color: var(--yellow);
  font-weight: 700;
  font-size: 15px;
}

.menu-toggle {
  display: none;
  border: none;
  background: var(--blue-dark);
  color: var(--white);
  font-size: 24px;
  width: 44px;
  height: 44px;
  border-radius: 8px;
  cursor: pointer;
}

.hero-section {
  position: relative;
  min-height: 650px;
  display: flex;
  align-items: center;
  background:
    linear-gradient(rgba(11, 31, 77, 0.82), rgba(11, 31, 77, 0.9)),
    url("images/doi-ngu-bao-ve.jpg") center/cover no-repeat;
  overflow: hidden;
}

.hero-section::after {
  content: "";
  position: absolute;
  inset: auto -120px -180px auto;
  width: 420px;
  height: 420px;
  background: rgba(246, 196, 0, 0.18);
  border-radius: 50%;
}

.hero-content {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: 1.3fr 0.7fr;
  align-items: center;
  gap: 50px;
  color: var(--white);
}

.sub-title,
.section-subtitle {
  color: var(--yellow);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  font-size: 14px;
  margin-bottom: 12px;
}

.hero-text h1 {
  font-size: clamp(36px, 6vw, 64px);
  line-height: 1.12;
  margin-bottom: 22px;
}

.hero-text p {
  max-width: 680px;
  font-size: 18px;
  color: rgba(255, 255, 255, 0.9);
}

.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 28px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 700;
  border: 2px solid transparent;
  transition: 0.25s;
  cursor: pointer;
}

.btn-primary {
  background: var(--yellow);
  color: var(--blue-dark);
  border-color: var(--yellow);
}

.btn-primary:hover {
  background: var(--yellow-dark);
  border-color: var(--yellow-dark);
}

.btn-outline {
  color: var(--white);
  border-color: var(--white);
}

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

.btn-outline.dark {
  color: var(--blue-dark);
  border-color: var(--blue-dark);
}

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

.hero-card {
  background: rgba(255, 255, 255, 0.96);
  color: var(--blue-dark);
  padding: 28px;
  border-radius: 20px;
  box-shadow: var(--shadow);
  text-align: center;
}

.hero-card img {
  width: 230px;
  height: 230px;
  object-fit: contain;
  margin: 0 auto 20px;
}

.hero-card h3 {
  font-size: 24px;
  margin-bottom: 8px;
}

.hero-card p {
  color: var(--muted);
}

.about-grid,
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 46px;
  align-items: center;
}

.about-image img {
  border-radius: 22px;
  box-shadow: var(--shadow);
  height: 440px;
  width: 100%;
  object-fit: cover;
}

.about-content h2,
.section-heading h2,
.contact-content h2 {
  color: var(--blue-dark);
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.25;
  margin-bottom: 18px;
}

.about-content p,
.contact-content p {
  color: var(--muted);
  margin-bottom: 14px;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin-top: 28px;
}

.about-stats div {
  background: var(--light-bg);
  border: 1px solid var(--border);
  padding: 18px;
  border-radius: 16px;
  text-align: center;
}

.about-stats strong {
  display: block;
  color: var(--blue-dark);
  font-size: 28px;
}

.about-stats span {
  color: var(--muted);
  font-size: 14px;
}

.why-section,
.activity-section,
.partner-section {
  background: var(--light-bg);
}

.section-heading {
  max-width: 760px;
  text-align: center;
  margin: 0 auto 46px;
}

.why-grid,
.service-grid,
.testimonial-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}

.why-card,
.service-card,
.testimonial-card {
  background: var(--white);
  padding: 28px;
  border-radius: 20px;
  box-shadow: 0 8px 28px rgba(0, 0, 0, 0.07);
  border: 1px solid var(--border);
  transition: 0.25s;
}

.why-card:hover,
.service-card:hover,
.testimonial-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow);
}

.why-card .icon {
  width: 52px;
  height: 52px;
  background: var(--blue-dark);
  color: var(--yellow);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  margin-bottom: 18px;
}

.why-card h3,
.service-card h3,
.testimonial-card strong {
  color: var(--blue-dark);
  margin-bottom: 10px;
}

.why-card p,
.service-card p,
.testimonial-card p {
  color: var(--muted);
}

.service-grid {
  grid-template-columns: repeat(4, 1fr);
}

.service-card {
  position: relative;
  overflow: hidden;
}

.service-card::before {
  content: "";
  position: absolute;
  width: 70px;
  height: 5px;
  top: 0;
  left: 28px;
  background: var(--yellow);
  border-radius: 999px;
}

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

.image-card {
  background: var(--white);
  border-radius: 20px;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.image-card img {
  width: 100%;
  height: 260px;
  object-fit: cover;
}

.image-card div {
  padding: 22px;
}

.image-card h3 {
  color: var(--blue-dark);
  margin-bottom: 8px;
}

.image-card p {
  color: var(--muted);
}

.testimonial-grid {
  grid-template-columns: repeat(3, 1fr);
}

.testimonial-card p {
  margin-bottom: 18px;
  font-style: italic;
}

.partner-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
}

.partner-grid div {
  background: var(--white);
  color: var(--blue-dark);
  padding: 22px 12px;
  border-radius: 16px;
  text-align: center;
  font-weight: 700;
  border: 1px solid var(--border);
  box-shadow: 0 8px 22px rgba(0, 0, 0, 0.06);
}

.contact-section {
  background: linear-gradient(135deg, #ffffff 0%, #f5f7fb 100%);
}

.contact-list {
  list-style: none;
  margin: 22px 0;
}

.contact-list li {
  margin-bottom: 10px;
  color: var(--text);
}

.contact-form {
  background: var(--white);
  padding: 32px;
  border-radius: 22px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.contact-form h3 {
  color: var(--blue-dark);
  font-size: 24px;
  margin-bottom: 20px;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 14px 16px;
  margin-bottom: 14px;
  border: 1px solid var(--border);
  border-radius: 12px;
  outline: none;
  font-size: 15px;
  font-family: inherit;
}

.contact-form textarea {
  height: 120px;
  resize: vertical;
}

.contact-form input:focus,
.contact-form textarea:focus {
  border-color: var(--blue-main);
}

.form-note {
  font-size: 13px;
  color: var(--muted);
  margin-top: 14px;
}

.footer {
  background: var(--blue-dark);
  color: var(--white);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 1fr;
  gap: 40px;
  padding: 60px 0;
}

.footer-logo {
  width: 90px;
  height: 90px;
  object-fit: contain;
  border-radius: 12px;
  margin-bottom: 16px;
  background: var(--white);
}

.footer h3,
.footer h4 {
  color: var(--yellow);
  margin-bottom: 14px;
}

.footer p {
  color: rgba(255, 255, 255, 0.78);
  margin-bottom: 8px;
}

.footer a {
  display: block;
  color: rgba(255, 255, 255, 0.78);
  margin-bottom: 8px;
  transition: 0.25s;
}

.footer a:hover {
  color: var(--yellow);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.14);
  padding: 18px;
  text-align: center;
}

.fixed-buttons {
  position: fixed;
  right: 18px;
  bottom: 18px;
  z-index: 999;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.fixed-buttons a {
  min-width: 105px;
  text-align: center;
  padding: 12px 16px;
  border-radius: 999px;
  font-weight: 800;
  box-shadow: var(--shadow);
}

.fixed-call {
  background: var(--yellow);
  color: var(--blue-dark);
}

.fixed-zalo {
  background: #0068ff;
  color: var(--white);
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: 0.7s ease;
}

.reveal.active {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 1024px) {
  .header-hotline {
    display: none;
  }

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

  .partner-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .hero-content,
  .about-grid,
  .contact-grid {
    grid-template-columns: 1fr;
  }

  .hero-section {
    padding: 70px 0;
  }
}

@media (max-width: 768px) {
  .header-inner {
    height: 74px;
  }

  .logo-box img {
    width: 50px;
    height: 50px;
  }

  .logo-box strong {
    font-size: 15px;
  }

  .logo-box span {
    font-size: 12px;
  }

  .menu-toggle {
    display: block;
  }

  .main-nav {
    position: absolute;
    top: 74px;
    left: 0;
    right: 0;
    background: var(--white);
    flex-direction: column;
    align-items: flex-start;
    padding: 18px 24px;
    border-top: 1px solid var(--border);
    box-shadow: 0 15px 25px rgba(0, 0, 0, 0.08);
    display: none;
  }

  .main-nav.active {
    display: flex;
  }

  .hero-section {
    min-height: auto;
  }

  .hero-content {
    gap: 30px;
  }

  .hero-card img {
    width: 180px;
    height: 180px;
  }

  .about-stats,
  .why-grid,
  .service-grid,
  .image-grid,
  .testimonial-grid,
  .partner-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .section-padding {
    padding: 58px 0;
  }

  .about-image img {
    height: 300px;
  }

  .fixed-buttons {
    left: 12px;
    right: 12px;
    bottom: 12px;
    flex-direction: row;
  }

  .fixed-buttons a {
    flex: 1;
  }

  .footer-bottom {
    padding-bottom: 82px;
  }
}

@media (max-width: 480px) {
  .container {
    width: min(100% - 24px, 1180px);
  }

  .hero-text h1 {
    font-size: 32px;
  }

  .hero-text p {
    font-size: 16px;
  }

  .btn {
    width: 100%;
  }

  .hero-buttons {
    width: 100%;
  }

  .contact-form {
    padding: 24px;
  }
}