:root {
  --bg: #f0f2f5;
  --text: #1a1a2e;
  --nav-bg: #fff;
  --nav-border: #ddd;
  --nav-hover: #e6e9f0;
  --card-bg: #fff;
  --card-shadow: rgba(0,0,0,0.1);
  --card-shadow-hover: rgba(0,0,0,0.15);
  --card-text: #555;
  --table-bg: #fff;
  --table-border: #e0e0e0;
  --table-empty: #f9f9f9;
  --input-border: #ccc;
  --input-focus: rgba(26, 26, 46, 0.15);
  --btn-bg: #fff;
  --primary: #1a1a2e;
  --primary-light: #16213e;
  --header-text: #fff;
}

html.dark {
  --bg: #121212;
  --text: #e0e0e0;
  --nav-bg: #1e1e1e;
  --nav-border: #333;
  --nav-hover: #333;
  --card-bg: #1e1e1e;
  --card-shadow: rgba(0,0,0,0.4);
  --card-shadow-hover: rgba(0,0,0,0.6);
  --card-text: #aaa;
  --table-bg: #1e1e1e;
  --table-border: #333;
  --table-empty: #181818;
  --input-border: #555;
  --input-focus: rgba(255,255,255,0.15);
  --btn-bg: #2a2a2a;
  --primary: #3a3a5c;
  --primary-light: #4a4a6e;
  --header-text: #e0e0e0;
}

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

body {
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  transition: background 0.3s, color 0.3s;
}

header {
  text-align: center;
  padding: 3rem 1rem;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: var(--header-text);
}

header h1 {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
}

.logo-header {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
}

.site-logo {
  flex-shrink: 0;
  animation: spin 10s linear infinite;
}

.logo-hex {
  animation: spin-reverse 20s linear infinite;
  transform-origin: center;
}

.logo-circle {
  animation: pulse 3s ease-in-out infinite;
  transform-origin: center;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

@keyframes spin-reverse {
  to { transform: rotate(-360deg); }
}

@keyframes pulse {
  0%, 100% { opacity: 0.4; }
  50% { opacity: 1; }
}

.tagline {
  opacity: 0.8;
  font-size: 1.1rem;
}

nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 2rem;
  padding: 1rem;
  background: var(--nav-bg);
  border-bottom: 1px solid var(--nav-border);
  position: sticky;
  top: 0;
  z-index: 10;
  transition: background 0.3s, border-color 0.3s;
}

nav a {
  color: var(--text);
  text-decoration: none;
  font-weight: 500;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  transition: background 0.2s;
}

nav a:hover {
  background: var(--nav-hover);
}

.theme-switch {
  position: relative;
  width: 42px;
  height: 22px;
  cursor: pointer;
  flex-shrink: 0;
}

.theme-switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  position: absolute;
  inset: 0;
  background: var(--nav-hover);
  border-radius: 22px;
  transition: background 0.3s;
}

.slider::before {
  content: '';
  position: absolute;
  width: 16px;
  height: 16px;
  left: 3px;
  bottom: 3px;
  background: var(--text);
  border-radius: 50%;
  transition: transform 0.3s, background 0.3s;
}

.theme-switch input:checked + .slider::before {
  transform: translateX(20px);
}

main {
  max-width: 960px;
  margin: 0 auto;
  padding: 2rem 1rem;
}

section {
  margin-bottom: 3rem;
}

section h2 {
  font-size: 1.75rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 3px solid var(--primary);
}

section p {
  margin-bottom: 0.75rem;
}

ul {
  padding-left: 1.5rem;
}

ul li {
  margin-bottom: 0.4rem;
}

.gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.card {
  background: var(--card-bg);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 8px var(--card-shadow);
  transition: transform 0.2s, box-shadow 0.2s, background 0.3s;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 6px 20px var(--card-shadow-hover);
}

.card img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  display: block;
}

.card p {
  padding: 0.75rem;
  font-size: 0.9rem;
  color: var(--card-text);
}

.calendar-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 1rem;
}

.calendar-controls button {
  padding: 0.4rem 1rem;
  border: 1px solid var(--primary);
  border-radius: 4px;
  background: var(--btn-bg);
  cursor: pointer;
  font-size: 0.9rem;
  color: var(--text);
  transition: background 0.2s, color 0.2s;
}

.calendar-controls button:hover {
  background: var(--primary);
  color: var(--header-text);
}

#monthYear {
  font-size: 1.2rem;
  font-weight: 600;
  min-width: 160px;
  text-align: center;
}

#calendarTable {
  width: 100%;
  border-collapse: collapse;
  background: var(--table-bg);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 8px var(--card-shadow);
  transition: background 0.3s;
}

#calendarTable th,
#calendarTable td {
  text-align: center;
  padding: 0.75rem;
  border: 1px solid var(--table-border);
}

#calendarTable th {
  background: var(--primary);
  color: var(--header-text);
  font-weight: 500;
  font-size: 0.85rem;
}

#calendarTable td {
  font-size: 0.95rem;
}

#calendarTable td.empty {
  background: var(--table-empty);
}

#calendarTable td.today {
  background: var(--primary-light);
  color: var(--header-text);
  font-weight: 700;
  border-radius: 4px;
}

form {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  max-width: 480px;
}

.form-label {
  font-weight: 500;
  font-size: 0.9rem;
}

input,
textarea {
  padding: 0.6rem;
  border: 1px solid var(--input-border);
  border-radius: 4px;
  font-size: 1rem;
  font-family: inherit;
  background: var(--card-bg);
  color: var(--text);
  transition: background 0.3s, color 0.3s, border-color 0.3s;
}

input:focus,
textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--input-focus);
}

form button[type="submit"] {
  align-self: flex-start;
  padding: 0.6rem 2rem;
  border: none;
  border-radius: 4px;
  background: var(--primary);
  color: var(--header-text);
  font-size: 1rem;
  cursor: pointer;
  transition: background 0.2s;
}

form button[type="submit"]:hover {
  background: var(--primary-light);
}

.feedback {
  font-size: 0.9rem;
  min-height: 1.2rem;
}

.feedback.success {
  color: #2e7d32;
}

.feedback.error {
  color: #c62828;
}

footer {
  text-align: center;
  padding: 2rem;
  background: var(--primary);
  color: var(--header-text);
  font-size: 0.85rem;
  transition: background 0.3s;
}

footer .small {
  opacity: 0.6;
  margin-top: 0.25rem;
}