/* General Styles */
:root {
  --primary-blue: #3498db;
  --secondary-blue: #2980b9;
  --light-blue: #ecf0f1;
  --dark-grey: #34495e;
  --medium-grey: #7f8c8d;
  --light-grey: #f4f6f9;
  --white: #ffffff;
  --text-color: #333;
  --border-color: #ddd;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Inter", sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background-color: var(--white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

h1,
h2,
h3 {
  color: var(--dark-grey);
  margin-bottom: 1rem;
  font-weight: 600;
  line-height: 1.2;
}

h1 {
  font-size: 2.8rem;
  text-align: center;
}

h2 {
  font-size: 2.2rem;
  text-align: center;
  margin-bottom: 2.5rem;
}

h3 {
  font-size: 1.6rem;
}

p {
  margin-bottom: 1rem;
  font-size: 1.1rem;
  line-height: 1.7;
  color: var(--medium-grey);
}

ul {
  list-style: none;
  padding-left: 0;
  margin-bottom: 1rem;
}

ul li {
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
  line-height: 1.7;
  color: var(--medium-grey);
  position: relative;
  padding-left: 25px; /* Space for custom bullet */
}

ul li::before {
  content: "•"; /* Custom bullet point */
  color: var(--primary-blue);
  font-size: 1.5em;
  position: absolute;
  left: 0;
  top: -2px;
}

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

a:hover {
  color: var(--secondary-blue);
}

/* Buttons */
.button {
  display: inline-block;
  padding: 12px 25px;
  border-radius: 5px;
  font-weight: 500;
  text-align: center;
  transition: background-color 0.3s ease, transform 0.2s ease;
  cursor: pointer;
  border: none;
  font-size: 1rem;
}

.button.primary {
  background-color: var(--primary-blue);
  color: var(--white);
}

.button.primary:hover {
  background-color: var(--secondary-blue);
  transform: translateY(-2px);
}

/* Header */
#main-header {
  background-color: var(--white);
  padding: 15px 0;
  border-bottom: 1px solid var(--border-color);
  position: fixed;
  width: 100%;
  top: 0;
  left: 0;
  z-index: 1000;
  transition: all 0.3s ease;
}

#main-header.sticky {
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  background-color: rgba(255, 255, 255, 0.95);
}

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

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

.logo a:hover {
  color: var(--primary-blue);
}

/* Header Logo */
.header-logo {
  height: 40px; /* Adjust as needed */
  width: auto;
  transition: transform 0.3s ease;
}

.header-logo:hover {
  transform: scale(1.05);
}

nav ul {
  list-style: none;
  display: flex;
}

nav ul li {
  margin-left: 30px;
}

nav ul li a {
  font-weight: 500;
  color: var(--medium-grey);
  font-size: 1.05rem;
  position: relative;
}

nav ul li a::after {
  content: "";
  position: absolute;
  width: 0;
  height: 2px;
  bottom: -5px;
  left: 0;
  background-color: var(--primary-blue);
  transition: width 0.3s ease;
}

nav ul li a:hover::after {
  width: 100%;
}

/* Hero Section (General) */
.hero-section {
  padding: 150px 0 100px;
  text-align: center;
  margin-top: 65px; /* Offset for fixed header */
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 600px;
}

.hero-section.small-hero {
  min-height: 300px; /* Smaller hero for about page */
  padding: 100px 0 60px;
}

.hero-background {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: url("/blood-pressure-3524615_1280.jpg?height=800&width=1600");
  background-size: cover;
  background-position: center;
  filter: brightness(0.6);
  z-index: 0;
}

.hero-section .container {
  position: relative;
  z-index: 1;
  color: var(--white);
}

.hero-section h1,
.hero-section .subtext,
.hero-section p {
  color: var(--white);
}

/* Content Sections (for About page and Research sections) */
.content-section {
  padding: 80px 0;
  background-color: var(--white);
  text-align: center;
}

.content-section.alt-background {
  background-color: var(--light-grey);
}

.content-section h2 {
  margin-bottom: 1.5rem;
  color: var(--primary-blue);
}

.content-section p,
.content-section ul {
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
  text-align: left;
}

.content-section p:last-of-type {
  margin-bottom: 0;
}

.section-label {
  display: inline-block;
  background-color: var(--primary-blue);
  color: var(--white);
  padding: 5px 15px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 20px;
}

.section-image {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  margin: 30px auto;
  display: block;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

/* Contact Details Grid for Contact Page */
.contact-details-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
  margin-top: 40px;
  text-align: center;
}

.detail-block {
  background-color: var(--white);
  padding: 30px;
  border-radius: 8px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.detail-block:hover {
  transform: translateY(-5px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1);
}

.detail-block h3 {
  color: var(--primary-blue);
  margin-bottom: 15px;
  font-size: 1.4rem;
}

.detail-block p {
  font-size: 1rem;
  color: var(--medium-grey);
  margin-bottom: 5px;
  line-height: 1.5;
}

.detail-block p:last-child {
  margin-bottom: 0;
}

.detail-block a {
  font-weight: 500;
}

.intro-text {
  max-width: 700px;
  margin: 0 auto 40px;
  text-align: center;
  font-size: 1.15rem;
  color: var(--dark-grey);
}

/* Footer / About Section */
footer {
  background-color: var(--dark-grey);
  color: var(--white);
  padding: 60px 0 20px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-about h2 {
  color: var(--white);
  text-align: left;
  margin-bottom: 20px;
  display: none; /* Hide the original h2 if it's still there for some reason */
}

.footer-about p {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 10px;
}

/* Footer Logo */
.footer-logo {
  height: 50px; /* Adjust as needed */
  width: auto;
  filter: invert(1); /* Invert colors for dark background */
  margin-bottom: 20px; /* Space below the logo */
}

.footer-contact h3 {
  color: var(--white);
  text-align: left;
  margin-bottom: 20px;
}

.contact-form {
  padding: 0;
  border: none;
  background-color: transparent;
  text-align: left;
}

.form-group {
  margin-bottom: 15px;
}

.form-group label {
  display: block;
  margin-bottom: 5px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.9);
  font-size: 0.95rem;
}

.form-group input[type="text"],
.form-group input[type="email"],
.form-group textarea {
  width: 100%;
  padding: 10px;
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: 5px;
  font-size: 1rem;
  font-family: "Inter", sans-serif;
  color: var(--white);
  background-color: rgba(255, 255, 255, 0.1);
  transition: border-color 0.3s ease, background-color 0.3s ease;
}

.form-group input[type="text"]:focus,
.form-group input[type="email"]:focus,
.form-group textarea:focus {
  border-color: var(--primary-blue);
  background-color: rgba(255, 255, 255, 0.2);
  outline: none;
  box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

.contact-form button {
  width: auto;
  padding: 10px 20px;
  font-size: 1rem;
}

.footer-bottom {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-top: 20px;
}

.footer-links {
  margin-bottom: 15px;
}

.footer-links a {
  color: var(--white);
  margin: 0 15px;
  font-size: 0.9rem;
  transition: color 0.3s ease;
}

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

.small-print {
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.6);
  max-width: 700px;
  margin: 0 auto;
  text-align: center;
}

/* Animations on Scroll (Initial State) */
section {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

section.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Responsive Design */
@media (max-width: 768px) {
  h1 {
    font-size: 2.2rem;
  }

  h2 {
    font-size: 1.8rem;
  }

  h3 {
    font-size: 1.4rem;
  }

  p,
  ul li {
    font-size: 1rem;
  }

  .hero-section {
    min-height: 450px;
    padding: 100px 0 60px;
  }

  .hero-section.small-hero {
    min-height: 250px;
    padding: 80px 0 40px;
  }

  .hero-background {
    filter: brightness(0.5);
  }

  .logo a {
    font-size: 1.5rem;
  }

  nav ul {
    flex-direction: column;
    align-items: center;
    margin-top: 15px;
  }

  nav ul li {
    margin: 10px 0;
  }

  .header-content {
    flex-direction: column;
  }

  .content-section p,
  .content-section ul {
    text-align: center;
  }

  .contact-details-grid {
    grid-template-columns: 1fr; /* Stack contact details on small screens */
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }

  .footer-about h2,
  .footer-contact h3 {
    text-align: center;
  }

  .footer-about p {
    text-align: center;
  }

  /* Responsive adjustments for logos */
  .header-logo {
    height: 35px;
  }
  .footer-logo {
    height: 45px;
  }
}

@media (max-width: 480px) {
  h1 {
    font-size: 1.8rem;
  }

  h2 {
    font-size: 1.6rem;
  }

  .hero-section {
    min-height: 350px;
  }

  .hero-section.small-hero {
    min-height: 200px;
  }

  .button {
    padding: 10px 20px;
    font-size: 0.9rem;
  }

  .footer-links a {
    margin: 0 10px;
  }

  /* Responsive adjustments for logos */
  .header-logo {
    height: 30px;
  }
  .footer-logo {
    height: 40px;
  }
}