:root {
  /* Color Variables */
  --primary-color: #2A7FFF;
  --primary-hover: #1F64CC;
  --text-color: #333;
  --light-text-color: #666;
  --background-color: #FAFAFA;
  --header-bg: #FFFFFF;
  --footer-bg: #F5F5F5;
  --card-bg: #FFFFFF;
  --border-color: #DDD;
  --highlight-color: #F0F8FF;

  /* Font Sizing and Spacing */
  --base-font-size: 16px;
  --heading-font-size: 2rem;
  --subheading-font-size: 1.5rem;
  --text-font-size: 1rem;
  --small-text-size: 0.875rem;
  --line-height: 1.5;
  --content-width: 800px;
  --section-padding: 40px;
  --card-padding: 20px;
}

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

body {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
  font-family: sans-serif;
  font-size: var(--base-font-size);
  line-height: var(--line-height);
  color: var(--text-color);
  background-color: var(--background-color);
}

/* Layout */
.header, .footer {
  width: 100%;
  background: var(--header-bg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 20px;
  border-bottom: 1px solid var(--border-color);
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: var(--header-bg);
    padding: 10px 20px;
    border-bottom: 1px solid var(--border-color);
}

.footer {
  background: var(--footer-bg);
  border-top: 1px solid var(--border-color);
  justify-content: center;
}

.logo {
  text-decoration: none;
  font-size: 1.2rem;
  font-weight: bold;
  color: var(--primary-color);
}

.logo-link {
  text-decoration: none;
  font-weight: bold;
}

.nav ul {
  list-style: none;
  display: flex;
  gap: 20px;
}

.nav a {
  text-decoration: none;
  color: var(--text-color);
  font-weight: 500;
  padding: 5px 10px;
  transition: background-color 0.3s;
}

.nav a.active {
  background: var(--highlight-color);
  border-radius: 4px;
  color: var(--primary-color);
}

.nav a:hover {
  background: var(--highlight-color);
  border-radius: 4px;
}

.main-content {
    flex: 1;
    padding-top: calc(10px + 5rem);  /* Dynamic padding based on navbar height */
    max-width: var(--content-width);
    margin: 0 auto;
}

.section {
  margin-bottom: var(--section-padding);
}

/* Hero Section */
.hero-section {
  text-align: center;
  padding: var(--section-padding) 0;
}

.hero-title {
  font-size: var(--heading-font-size);
  margin-bottom: 10px;
  color: var(--primary-color);
}

.hero-subtitle {
  font-size: var(--subheading-font-size);
  color: var(--text-color);
  margin-bottom: 20px;
}

.hero-summary {
  font-size: var(--text-font-size);
  color: var(--light-text-color);
  max-width: 600px;
  margin: 0 auto;
}

/* Screenshot Section */
.screenshot-section {
  text-align: center;
}

.screenshot-section h2 {
  font-size: var(--subheading-font-size);
  margin-bottom: 20px;
}

.screenshot-container {
  border: 1px solid var(--border-color);
  display: inline-block;
  padding: 20px;
  background: var(--card-bg);
}

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

/* Plans Section */
.plans-section h2 {
  font-size: var(--subheading-font-size);
  text-align: center;
  margin-bottom: 40px;
}

.plans-grid {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  justify-content: center;
}

.plan-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  padding: var(--card-padding);
  width: calc((var(--content-width) - 60px)/4);
  box-sizing: border-box;
  text-align: center;

}

.plan-title {
  font-size: 1.2rem;
  color: var(--primary-color);
  margin-bottom: 10px;
}

.plan-price {
  font-size: 1rem;
  font-weight: bold;
  margin-bottom: 15px;
}

.plan-features {
  list-style: none;
  font-size: var(--small-text-size);
  line-height: 1.4;
  color: var(--light-text-color);
  padding: 0;
}

/* Download Page */
.download-section h1 {
  font-size: var(--heading-font-size);
  text-align: center;
  margin-bottom: 20px;
}

.download-section p {
  text-align: center;
  margin-bottom: 20px;
  color: var(--light-text-color);
}

.os-selector {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-bottom: 30px;
}

.os-button {
  background: var(--primary-color);
  color: #fff;
  border: none;
  padding: 10px 20px;
  cursor: pointer;
  border-radius: 4px;
  font-size: var(--text-font-size);
  transition: background-color 0.3s;
}

.os-button:hover {
  background: var(--primary-hover);
}

.os-button.active-os {
  text-decoration: underline;
}

.download-links {
  text-align: center;
}

.download-links h2 {
  font-size: var(--subheading-font-size);
  margin-bottom: 10px;
}

.download-links p {
  font-size: var(--text-font-size);
  margin-bottom: 10px;
}

/* Footer Text */
.footer p {
  font-size: var(--small-text-size);
  color: var(--light-text-color);
}

.flash-banner {
  /* Use a highlight or a subtle background color that fits your theme */
  background-color: var(--highlight-color);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  max-width: var(--content-width);
  margin: 80px auto 20px auto; /* 80px top margin can help
                                  if your fixed header is about 70px high */
  padding: 15px;
  text-align: center;
}

.flash-message {
  font-size: var(--text-font-size);
  color: var(--text-color);
  margin: 5px 0;
}

/* Optionally style messages by category,
   e.g. .flash-message.error, .flash-message.success, .flash-message.info
   if you use them. */
.flash-message.error {
  color: #ff3333; /* or any color that suits errors */
}
.flash-message.success {
  color: green;
}