* {
  box-sizing: border-box;
}

:root {
  /* Light theme variables */
  --bg-gradient-start: #f4f7ff;
  --bg-gradient-end: #eef7f0;
  --text-color: #1b1f2a;
  --container-bg: #ffffff;
  --container-border: #e5eaf5;
  --container-shadow: rgba(31, 44, 80, 0.08);
  --subtitle-color: #4c5466;
  --card-bg: #fafcff;
  --card-border: #e3e8f2;
  --button-bg: #2563eb;
  --button-hover-filter: brightness(0.95);
  --secondary-button-bg: #64748b;
  --result-text-color: #1b1f2a;
}

[data-theme='dark'] {
  /* Dark theme variables */
  --bg-gradient-start: #2c3e50;
  --bg-gradient-end: #1a2c3a;
  --text-color: #e0e0e0;
  --container-bg: #34495e;
  --container-border: #4a6582;
  --container-shadow: rgba(0, 0, 0, 0.3);
  --subtitle-color: #b0c4de;
  --card-bg: #2b3a4a;
  --card-border: #3c5169;
  --button-bg: #4a90e2;
  --button-hover-filter: brightness(1.1);
  --secondary-button-bg: #7f8c8d;
  --result-text-color: #e0e0e0;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", "Malgun Gothic", sans-serif;
  background: linear-gradient(135deg, var(--bg-gradient-start) 0%, var(--bg-gradient-end) 100%);
  color: var(--text-color);
  transition: background 0.3s ease, color 0.3s ease;
}

.container {
  max-width: 760px;
  margin: 48px auto;
  padding: 28px;
  text-align: center;
  background: var(--container-bg);
  border: 1px solid var(--container-border);
  border-radius: 16px;
  box-shadow: 0 10px 30px var(--container-shadow);
  transition: background 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

h1 {
  margin: 0;
  font-size: 2.2rem;
}

.subtitle {
  margin: 10px 0 24px;
  color: var(--subtitle-color);
  transition: color 0.3s ease;
}

.result-section {
  padding: 24px;
  border: 1px solid var(--card-border);
  border-radius: 12px;
  background: var(--card-bg);
  transition: background 0.3s ease, border-color 0.3s ease;
}

.result-section h2 {
  margin: 0 0 16px;
  font-size: 1.2rem;
}

.menu-result-display {
  min-height: 100px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--result-text-color);
  transition: color 0.3s ease;
}

.actions {
  margin: 24px 0 10px;
  display: flex;
  justify-content: center;
  gap: 10px;
}

button {
  padding: 14px 28px;
  border: 0;
  border-radius: 10px;
  background: var(--button-bg);
  color: #fff;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.3s ease;
}

button:hover {
  filter: var(--button-hover-filter);
}

button.secondary {
  background: var(--secondary-button-bg);
}

/* Theme Toggle Styles */
.theme-toggle-wrapper {
  position: absolute;
  top: 10px;
  right: 10px;
}

.theme-toggle {
  display: none; /* Hide the default checkbox */
}

.theme-toggle-label {
  --toggle-size: 24px;
  --toggle-padding: 4px;
  --toggle-width: calc(var(--toggle-size) * 2 + var(--toggle-padding) * 2);
  --toggle-height: calc(var(--toggle-size) + var(--toggle-padding) * 2);
  --toggle-border-radius: calc(var(--toggle-height) / 2);

  position: relative;
  display: inline-flex;
  align-items: center;
  width: var(--toggle-width);
  height: var(--toggle-height);
  background-color: #ccc;
  border-radius: var(--toggle-border-radius);
  cursor: pointer;
  transition: background-color 0.3s ease;
  padding: var(--toggle-padding);
}

.theme-toggle-label::before {
  content: '';
  position: absolute;
  width: var(--toggle-size);
  height: var(--toggle-size);
  border-radius: 50%;
  background-color: white;
  transition: transform 0.3s ease;
  transform: translateX(0);
  box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

.theme-toggle:checked + .theme-toggle-label {
  background-color: #4a90e2;
}

.theme-toggle:checked + .theme-toggle-label::before {
  transform: translateX(var(--toggle-size));
}

.theme-toggle-label .icon {
  position: absolute;
  font-size: 1.2em;
  line-height: 1;
  pointer-events: none;
  transition: opacity 0.3s ease;
  color: #f1c40f;
}

.theme-toggle-label .light-icon {
  left: 5px;
  opacity: 1;
}

.theme-toggle-label .dark-icon {
  right: 5px;
  opacity: 0;
  color: #fff;
}

.theme-toggle:checked + .theme-toggle-label .light-icon {
  opacity: 0;
}

.theme-toggle:checked + .theme-toggle-label .dark-icon {
  opacity: 1;
}