/* Modern and professional CSS for logistics consulting firm website */

/* General Styles */
:root {
  --dark-gray: #333333; /* Primary text color */
  --green: rgb(90, 168, 50); /* Accent color for CTAs and hovers */
  --off-white: #F4F4F4; /* Section backgrounds */
  --white: #FFFFFF; /* Content blocks */
  --dark-bg: #2C3E50; /* Footer background */
  --light-gray: #666666; /* Secondary text (meta info) */
}

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

body {
  font-family: 'Helvetica Neue', 'Lucida Sans', Arial, sans-serif;
  color: var(--dark-gray);
  background: var(--off-white);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3 {
  font-family: 'Helvetica Neue', 'Lucida Sans', Arial, sans-serif;
  font-weight: 700;
  color: var(--dark-gray);
}

h1 {
  font-size: 3rem;
  margin-bottom: 1.5rem;
}

h2 {
  font-size: 2.4rem;
  margin-bottom: 2rem;
  position: relative;
  padding-bottom: 0.5rem;
}

h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 50px;
  height: 3px;
  background: var(--green);
}

a {
  text-decoration: none;
  color: var(--dark-gray);
  transition: color 0.3s ease;
}

a:hover {
  color: var(--green);
}

a:focus, button:focus {
  outline: 3px solid var(--green);
  outline-offset: 3px;
}

/* Header and Navigation */
.fixed-header {
  position: fixed;
  top: 0;
  width: 100%;
  background: var(--white);
  z-index: 1000;
  padding: 1.5rem 2rem;
  border-bottom: 1px solid var(--off-white);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
}

.logo {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--dark-gray);
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-link {
  font-size: 1rem;
  color: var(--dark-gray);
  font-weight: 400;
  transition: color 0.3s ease;
}

.nav-link:hover {
  color: var(--green);
}

.menu-icon {
  display: none;
  font-size: 1.8rem;
  color: var(--dark-gray);
  cursor: pointer;
}

/* Hero Section */
.hero {
  text-align: center;
  padding: 10rem 2rem 7rem;
  background: var(--off-white);
}

.profile-image {
  max-width: 200px;
  border-radius: 50%;
  margin-bottom: 2rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.hero-content {
  max-width: 800px;
  margin: 0 auto;
}

.hero p {
  font-size: 1.2rem;
  margin-bottom: 2rem;
}

.hero .cta-button {
  padding: 1rem 1.5rem;
  background: var(--green);
  color: var(--white);
  border: none;
  border-radius: 50px;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.3s ease, transform 0.2s ease;
}

.hero .cta-button:hover {
  background: #45A049;
  transform: translateY(-2px);
}

/* General Section Styles */
section {
  padding: 7rem 2rem;
  background: var(--off-white);
}

section:nth-child(even) {
  background: var(--white);
}

/* Education Section */
.education-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.education-item {
  background: var(--white);
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
  transition: background 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease, color 0.3s ease;
}

.education-item:hover {
  background: var(--green);
  color: var(--white);
  transform: translateY(-5px);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.1);
}

.education-item:hover h3,
.education-item:hover p {
  color: var(--white);
}

.education-item h3 {
  font-size: 1.4rem;
  margin-bottom: 1rem;
  transition: color 0.3s ease;
}

.education-item p {
  font-size: 1rem;
  color: var(--light-gray);
  transition: color 0.3s ease;
}

/* Skills Section */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1.5rem;
  max-width: 1200px;
  margin: 0 auto;
}

.skill-item {
  background: var(--white);
  padding: 1.5rem;
  text-align: center;
  border-radius: 50%;
  aspect-ratio: 1/1;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
  transition: background 0.3s ease, color 0.3s ease, transform 0.3s ease;
}

.skill-item:hover {
  background: var(--green);
  color: var(--white);
  transform: translateY(-5px);
}

/* Experience Section */
.experience-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.experience-item {
  background: var(--white);
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
  transition: background 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease, color 0.3s ease;
}

.experience-item:hover {
  background: var(--green);
  color: var(--white);
  transform: translateY(-5px);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.1);
}

.experience-item:hover h3,
.experience-item:hover .experience-meta,
.experience-item:hover ul li {
  color: var(--white);
}

.experience-item h3 {
  font-size: 1.4rem;
  margin-bottom: 0.5rem;
  transition: color 0.3s ease;
}

.experience-meta {
  font-size: 1rem;
  color: var(--light-gray);
  font-style: italic;
  margin-bottom: 1rem;
  transition: color 0.3s ease;
}

.experience-item ul {
  list-style: none;
  padding-left: 1.5rem;
}

.experience-item ul li {
  position: relative;
  font-size: 1rem;
  margin-bottom: 0.5rem;
  transition: color 0.3s ease;
}

.experience-item ul li::before {
  content: '';
  position: absolute;
  left: -1.5rem;
  top: 0.6rem;
  width: 8px;
  height: 8px;
  background: var(--green);
  border-radius: 50%;
}

.experience-item:hover ul li::before {
  background: var(--white);
}

/* About Section */
.about-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.about-content p {
  font-size: 1.2rem;
}

/* Contact Section */
.contact-intro {
  max-width: 800px;
  margin: 0 auto 2rem;
  text-align: center;
  font-size: 1.2rem;
}

.contact-form {
  display: grid;
  gap: 2rem;
  max-width: 700px;
  margin: 0 auto 3rem;
  background: var(--white);
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.15);
}

.form-group {
  display: flex;
  flex-direction: column;
}

.form-group label {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--dark-gray);
}

.form-group input,
.form-group textarea {
  padding: 1.2rem;
  border: 2px solid var(--dark-gray);
  border-radius: 5px;
  font-size: 1rem;
  background: var(--white);
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.form-group input:hover,
.form-group textarea:hover {
  border-color: var(--green);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--green);
  box-shadow: 0 0 8px rgba(76, 175, 80, 0.3);
  outline: none;
}

.form-group textarea {
  resize: vertical;
  min-height: 150px;
}

.form-group button.cta-button {
  padding: 1rem 1.5rem;
  background: var(--green);
  color: var(--white);
  border: none;
  border-radius: 50px;
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.3s ease, transform 0.2s ease;
}

.form-group button.cta-button:hover {
  background: #45A049;
  transform: translateY(-2px);
}

.contact-info-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.contact-info-item {
  background: var(--white);
  padding: 2rem;
  border-radius: 8px;
  text-align: center;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
  transition: background 0.3s ease, color 0.3s ease, transform 0.3s ease;
}

.contact-info-item:hover {
  background: var(--green);
  color: var(--white);
  transform: translateY(-5px);
}

.contact-info-item:hover h3,
.contact-info-item:hover p,
.contact-info-item:hover a {
  color: var(--white);
}

/* Footer */
footer {
  background: var(--dark-bg);
  color: var(--white);
  padding: 3rem 2rem;
  text-align: center;
}

.footer-logo {
  font-size: 1.6rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

footer p {
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  list-style: none;
  margin-top: 1rem;
}

.footer-links a {
  color: var(--white);
  font-size: 0.9rem;
}

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

/* Back to Top Button */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: var(--green);
  color: var(--white);
  border: none;
  border-radius: 50%;
  width: 50px;
  height: 50px;
  cursor: pointer;
  display: none;
  opacity: 0.7;
  transition: opacity 0.3s ease, transform 0.2s ease;
}

.back-to-top.show {
  display: block;
}

.back-to-top:hover {
  opacity: 1;
  transform: scale(1.1);
}

/* Media Queries for Responsiveness */

/* Tablet (768px–1199px) */
@media (max-width: 1199px) {
  .navbar {
    padding: 1.5rem;
  }

  .logo {
    font-size: 1.6rem;
  }

  .nav-links {
    gap: 1.5rem;
  }

  .nav-link {
    font-size: 0.95rem;
  }

  .hero {
    padding: 9rem 1.5rem 6rem;
  }

  h1 {
    font-size: 2.8rem;
  }

  h2 {
    font-size: 2.2rem;
  }

  .hero-content {
    max-width: 90%;
  }

  .hero p {
    font-size: 1.1rem;
  }

  .profile-image {
    max-width: 180px;
  }

  .contact-form {
    max-width: 90%;
    padding: 1.5rem;
  }

  .contact-intro {
    max-width: 90%;
    font-size: 1.1rem;
  }

  .education-grid,
  .experience-grid,
  .contact-info-grid {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  }

  .skills-grid {
    grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  }

  section {
    padding: 6rem 1.5rem;
  }

  footer {
    padding: 2.5rem 1.5rem;
  }

  .footer-logo {
    font-size: 1.4rem;
  }

  .footer-links {
    gap: 1rem;
  }
}

/* Smartphone (<768px) */
@media (max-width: 767px) {
  h1 {
    font-size: 2.5rem;
  }

  h2 {
    font-size: 2rem;
  }

  h3 {
    font-size: 1.2rem;
  }

  .navbar {
    flex-direction: column;
    align-items: flex-start;
    padding: 1rem 1.5rem;
  }

  .nav-links {
    display: none;
    flex-direction: column;
    width: 100%;
    text-align: center;
    margin-top: 1rem;
  }

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

  .nav-link {
    font-size: 1.1rem;
    padding: 0.5rem 0;
  }

  .menu-icon {
    display: block;
    position: absolute;
    right: 1.5rem;
    top: 1.5rem;
  }

  .hero {
    padding: 8rem 1.5rem 5rem;
  }

  .hero-content {
    max-width: 100%;
  }

  .hero p {
    font-size: 1rem;
  }

  .profile-image {
    max-width: 150px;
  }

  .cta-button {
    font-size: 1rem;
    padding: 0.8rem 1.2rem;
  }

  .education-grid,
  .skills-grid,
  .experience-grid,
  .contact-info-grid {
    grid-template-columns: 1fr;
  }

  .contact-form {
    width: 100%;
    padding: 1.5rem;
  }

  .contact-intro {
    font-size: 1rem;
  }

  .form-group label {
    font-size: 1rem;
  }

  .form-group input,
  .form-group textarea {
    padding: 1rem;
  }

  section {
    padding: 5rem 1.5rem;
  }

  footer {
    padding: 2rem 1.5rem;
  }

  .footer-logo {
    font-size: 1.3rem;
  }

  .footer-links {
    flex-direction: column;
    gap: 0.8rem;
  }

  .back-to-top {
    width: 40px;
    height: 40px;
    bottom: 20px;
    right: 20px;
  }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
  .cta-button,
  .education-item,
  .skill-item,
  .experience-item,
  .nav-link,
  .footer-links a,
  .back-to-top,
  .form-group input,
  .form-group textarea,
  .contact-info-item {
    transition: none;
  }
}

/* Lazy Loading Images */
img {
  loading: lazy;
}