/* Reset, page layout, header, hero and footer. */

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

body {
  font-family: var(--font-body);
  line-height: 1.6;
  background-color: var(--surface-secondary);
  color: var(--text-primary);
  transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.header {
  background: var(--surface-primary);
  box-shadow: 0 0.5px 1px var(--shadow-light);
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 16px 0;
}

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

.logo {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 600;
  color: var(--primary-blue);
  text-decoration: none;
}

.theme-toggle {
  background: var(--surface-secondary);
  border: 1px solid var(--border-light);
  border-radius: 20px;
  padding: 8px 16px;
  cursor: pointer;
  transition: all 0.2s ease;
  color: var(--text-secondary);
  font: inherit;
  font-size: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.theme-toggle:hover {
  background: var(--surface-tertiary);
  border-color: var(--border-medium);
}

/* Hero */
.hero {
  background: var(--surface-primary);
  padding: 80px 0;
  text-align: center;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: 48px;
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: 16px;
  line-height: 1.2;
}

.hero .subtitle {
  font-size: 20px;
  color: var(--text-secondary);
  margin-bottom: 24px;
  font-weight: 400;
}

.hero .quote {
  background: var(--surface-secondary);
  border-left: 4px solid var(--primary-blue);
  padding: 16px 24px;
  margin: 32px auto;
  max-width: 600px;
  font-style: italic;
  color: var(--text-secondary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

/* Main */
.main-content {
  padding: 48px 0;
}

.section {
  background: var(--surface-primary);
  border-radius: var(--radius-lg);
  padding: 48px;
  margin-bottom: 32px;
  box-shadow: 0 1px 3px var(--shadow-light);
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.section.animate-fade-in {
  opacity: 1;
  transform: translateY(0);
}

.section-title {
  font-family: var(--font-display);
  font-size: 32px;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 32px;
  position: relative;
}

.section-title::after {
  content: "";
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 48px;
  height: 3px;
  background: var(--primary-blue);
  border-radius: 2px;
}

/* Footer */
#copy-right {
  display: flex;
  justify-content: center;
  color: var(--border-medium);
}

/* 404 page */
.not-found {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  text-align: center;
  padding: 24px;
}

.not-found h1 {
  font-family: var(--font-display);
  font-size: 96px;
  font-weight: 500;
  color: var(--primary-blue);
  line-height: 1;
}

.not-found p {
  color: var(--text-secondary);
}