/* ==========================================================================
   MoPuzzle 2 — Design System & Visual Styles
   Aligned with MoPuzzle 1 Architecture, Tokens, and Hierarchy
   ========================================================================== */

:root {
  /* Default Light Theme */
  --bg-color: #F5F8FF;
  --bg-gradient: linear-gradient(135deg, #F5F8FF 0%, #E8F0FE 100%);
  --primary-color: #243A73;
  --primary-hover: #1A2B56;
  --accent-color: #A1E3F9;
  --accent-hover: #7BD5F5;
  --card-bg: #FFFFFF;
  --card-border: rgba(36, 58, 115, 0.08);
  --glass-bg: rgba(255, 255, 255, 0.88);
  --glass-border: rgba(255, 255, 255, 0.5);
  --text-main: #0D1B2A;
  --text-muted: #5B6B82;
  --success: #10B981;
  --danger: #EF4444;
  --shadow-sm: 0 2px 8px rgba(36, 58, 115, 0.06);
  --shadow-md: 0 8px 24px rgba(36, 58, 115, 0.09);
  --shadow-lg: 0 16px 36px rgba(36, 58, 115, 0.12);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --safe-top: env(safe-area-inset-top, 0px);
  --safe-bottom: env(safe-area-inset-bottom, 0px);

  /* Compatibility Aliases for Existing Games */
  --bg-primary: var(--bg-color);
  --bg-secondary: #E8F0FE;
  --primary: var(--primary-color);
  --primary-light: #3B82F6;
  --secondary: #3B82F6;
  --accent-gold: var(--accent-color);
  --accent-gold-dark: #38BDF8;
  --transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

[data-theme='dark'] {
  --bg-color: #101827;
  --bg-gradient: linear-gradient(135deg, #101827 0%, #162033 100%);
  --primary-color: #3B82F6;
  --primary-hover: #2563EB;
  --accent-color: #A1E3F9;
  --accent-hover: #7BD5F5;
  --card-bg: #1E2A3D;
  --card-border: rgba(255, 255, 255, 0.08);
  --glass-bg: rgba(30, 42, 61, 0.88);
  --glass-border: rgba(255, 255, 255, 0.12);
  --text-main: #F8FAFC;
  --text-muted: #94A3B8;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 16px 36px rgba(0, 0, 0, 0.45);

  /* Compatibility Aliases */
  --bg-primary: var(--bg-color);
  --bg-secondary: #162033;
  --primary: var(--primary-color);
  --primary-light: #60A5FA;
  --secondary: #60A5FA;
  --accent-gold: var(--accent-color);
  --accent-gold-dark: #38BDF8;
}

/* Base Reset & Typography */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

html {
  overflow-x: hidden;
  max-width: 100vw;
  box-sizing: border-box;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-color);
  background-image: var(--bg-gradient);
  color: var(--text-main);
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  max-width: 100vw;
  line-height: 1.5;
  transition: background-color 0.3s ease, color 0.3s ease;
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  touch-action: manipulation;
}

button:focus-visible, a:focus-visible {
  outline: 3px solid var(--accent-color);
  outline-offset: 2px;
}

/* ==========================================================================
   Header & Navbar (MoPuzzle 1 Aligned)
   ========================================================================== */

.app-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: var(--glass-bg);
  border-bottom: 1px solid var(--card-border);
  padding: calc(var(--safe-top) + 8px) 16px 8px 16px;
  width: 100%;
  max-width: 100vw;
  box-sizing: border-box;
}

.header-container {
  max-width: 1100px;
  width: 100%;
  box-sizing: border-box;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  text-decoration: none;
}

.brand-logo {
  width: 38px;
  height: 38px;
  border-radius: 9px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(36, 58, 115, 0.28);
  transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.2s ease;
}

.brand:hover .brand-logo {
  transform: scale(1.05);
  box-shadow: 0 4px 12px rgba(36, 58, 115, 0.38);
}

.brand-logo img,
.brand-logo svg {
  width: 100%;
  height: 100%;
  display: block;
}

.brand-text h1,
.brand-text .brand-title {
  font-size: 19px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--text-main);
  letter-spacing: -0.3px;
}

.brand-text p {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 500;
}

/* Desktop Header Navigation Tabs */
.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 13px;
  color: var(--text-muted);
  transition: var(--transition);
}

.nav-btn:hover, .nav-btn.active {
  color: var(--text-main);
  background: rgba(36, 58, 115, 0.08);
}

[data-theme='dark'] .nav-btn:hover, [data-theme='dark'] .nav-btn.active {
  color: var(--accent-color);
  background: rgba(161, 227, 249, 0.12);
}

.nav-btn.active {
  color: var(--primary-color);
  font-weight: 700;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.icon-btn {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  color: var(--text-main);
  width: 38px;
  height: 38px;
  min-width: 38px;
  min-height: 38px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: all 0.2s ease;
}

.icon-btn:hover {
  transform: translateY(-1px);
  border-color: var(--accent-color);
}

.icon-btn:active {
  transform: scale(0.96);
}

/* ==========================================================================
   Mobile Bottom Navigation
   ========================================================================== */

.bottom-nav {
  display: none;
  position: sticky;
  bottom: 0;
  z-index: 95;
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  background: var(--glass-bg);
  border-top: 1px solid var(--card-border);
  padding: 8px 12px calc(var(--safe-bottom) + 8px) 12px;
  justify-content: space-around;
  align-items: center;
  width: 100%;
  box-sizing: border-box;
}

.nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
  color: var(--text-muted);
  text-decoration: none;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 4px 10px;
  border-radius: var(--radius-md);
  font-size: 11px;
  font-weight: 600;
  transition: all 0.2s ease;
}

.nav-item.active {
  color: var(--primary-color);
  background: rgba(36, 58, 115, 0.08);
}

[data-theme='dark'] .nav-item.active {
  color: var(--accent-color);
  background: rgba(161, 227, 249, 0.12);
}

@media (max-width: 640px) {
  .nav-links {
    display: none;
  }
  .bottom-nav {
    display: flex;
  }
}

/* ==========================================================================
   Main Content Layout & Cards
   ========================================================================== */

.app-main {
  flex: 1;
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 20px 16px 40px;
  box-sizing: border-box;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 18px;
  box-shadow: var(--shadow-md);
  margin-bottom: 16px;
}

/* Continue Playing Banner */
.continue-card {
  background: linear-gradient(135deg, rgba(36, 58, 115, 0.95), rgba(58, 134, 255, 0.9));
  color: #FFFFFF;
  border-radius: var(--radius-lg);
  padding: 16px 20px;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  box-shadow: var(--shadow-md);
}

/* 6-Card Game Grid */
.game-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
}

@media (min-width: 520px) {
  .game-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 860px) {
  .game-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.game-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 20px;
  box-shadow: var(--shadow-md);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  cursor: pointer;
  transition: all 0.25s ease;
  position: relative;
  overflow: hidden;
  min-height: 190px;
}

.game-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
  border-color: var(--accent-color);
}

.game-card-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 26px;
  margin-bottom: 12px;
  box-shadow: var(--shadow-sm);
}

.game-card-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 4px;
  color: var(--text-main);
}

.game-card-sub {
  font-size: 12.5px;
  color: var(--text-muted);
  margin-bottom: 16px;
  line-height: 1.4;
}

.game-card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: auto;
  padding-top: 8px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 14px;
  cursor: pointer;
  border: none;
  transition: all 0.2s ease;
  text-decoration: none;
  min-height: 40px;
}

.btn-primary {
  background: var(--primary-color);
  color: #FFFFFF;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-1px);
}

.btn-secondary {
  background: rgba(36, 58, 115, 0.08);
  color: var(--text-main);
}

[data-theme='dark'] .btn-secondary {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-main);
}

.btn-accent {
  background: var(--accent-color);
  color: #0D1B2A;
}

.btn-accent:hover {
  background: var(--accent-hover);
}

.btn-danger {
  background: var(--danger);
  color: #FFFFFF;
}

.btn-block {
  width: 100%;
}

/* ==========================================================================
   Gameplay Shell & Canvas Containers
   ========================================================================== */

.gameplay-wrapper {
  display: flex;
  flex-direction: column;
  width: 100%;
  max-width: 680px;
  margin: 0 auto;
  position: relative;
}

.game-top-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
  gap: 8px;
}

.game-title-group {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.game-title-text {
  font-size: 17px;
  font-weight: 700;
  color: var(--text-main);
}

.game-mode-badge {
  font-size: 11px;
  font-weight: 600;
  background: var(--accent-color);
  color: #0D1B2A;
  padding: 2px 10px;
  border-radius: var(--radius-full);
}

.game-hud {
  display: flex;
  gap: 10px;
  justify-content: center;
  margin-bottom: 12px;
}

.hud-item {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  padding: 6px 14px;
  display: flex;
  flex-direction: column;
  align-items: center;
  min-width: 72px;
  box-shadow: var(--shadow-sm);
}

.hud-label {
  font-size: 10px;
  text-transform: uppercase;
  font-weight: 700;
  color: var(--text-muted);
  letter-spacing: 0.5px;
}

.hud-value {
  font-size: 17px;
  font-weight: 800;
  color: var(--text-main);
}

.game-canvas-container {
  width: 100%;
  position: relative;
  touch-action: none !important;
  user-select: none;
  -webkit-user-select: none;
  margin-bottom: 10px;
}

.puzzle-board-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  margin: 0 auto;
}

.game-controls-bar {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 12px;
  padding: 8px 0;
  flex-wrap: wrap;
}

.action-btn {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  color: var(--text-main);
  border-radius: var(--radius-md);
  padding: 8px 16px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: all 0.2s ease;
  min-height: 42px;
}

.action-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  border-color: var(--accent-color);
}

.action-btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

/* ==========================================================================
   Modals & Dialogs
   ========================================================================== */

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
  padding: 16px;
  animation: fadeIn 0.2s ease;
}

.modal-dialog {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  padding: 24px;
  width: 100%;
  max-width: 420px;
  box-shadow: var(--shadow-lg);
  animation: popIn 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.modal-title {
  font-size: 19px;
  font-weight: 700;
  color: var(--text-main);
}

.result-banner {
  text-align: center;
  padding: 12px 0 6px;
}

.result-icon {
  font-size: 48px;
  margin-bottom: 8px;
}

.result-title {
  font-size: 22px;
  font-weight: 800;
  color: var(--text-main);
}

/* Toasts */
.toast-container {
  position: fixed;
  top: calc(var(--safe-top) + 20px);
  right: 16px;
  z-index: 300;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
}

.toast {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  box-shadow: var(--shadow-lg);
  border-radius: var(--radius-md);
  padding: 12px 18px;
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-main);
  animation: slideInDown 0.3s ease;
  pointer-events: auto;
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes popIn {
  from { transform: scale(0.92); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

@keyframes slideInDown {
  from { transform: translateY(-20px); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

body.reduced-motion * {
  animation-duration: 0.01ms !important;
  animation-iteration-count: 1 !important;
  transition-duration: 0.01ms !important;
  scroll-behavior: auto !important;
}

/* Footer */
.app-footer {
  text-align: center;
  padding: 24px 16px;
  font-size: 12px;
  color: var(--text-muted);
  border-top: 1px solid var(--card-border);
  margin-top: auto;
}

.app-footer a {
  color: var(--primary-color);
  text-decoration: underline;
}

[data-theme='dark'] .app-footer a {
  color: var(--accent-color);
}

/* Level Select Grid & Badges (MoPuzzle 1 Alignment) */
.level-select-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 14px;
  margin-top: 14px;
}

@media (max-width: 600px) {
  .level-select-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
  }
}

.level-badge-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  aspect-ratio: 1;
  background: var(--card-bg);
  border: 1.5px solid var(--card-border);
  border-radius: var(--radius-md);
  color: var(--text-main);
  font-size: 18px;
  font-weight: 800;
  cursor: pointer;
  transition: all var(--trans-quick);
  box-shadow: var(--shadow-sm);
  position: relative;
  text-decoration: none;
}

.level-badge-btn:hover:not(:disabled) {
  transform: translateY(-3px);
  border-color: var(--primary-color);
  box-shadow: var(--shadow-md);
  color: var(--primary-color);
}

.level-badge-btn:disabled,
.level-badge-btn.locked {
  opacity: 0.45;
  cursor: not-allowed;
  background: rgba(0, 0, 0, 0.04);
}

[data-theme='dark'] .level-badge-btn:disabled,
[data-theme='dark'] .level-badge-btn.locked {
  background: rgba(255, 255, 255, 0.03);
  border-color: rgba(255, 255, 255, 0.08);
}

.level-badge-btn.completed {
  border-color: var(--accent-color);
  background: rgba(161, 227, 249, 0.08);
}

.level-stars-mini {
  color: #F59E0B;
  font-size: 11px;
  margin-top: 2px;
  letter-spacing: 1px;
}

.btn-game-action {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border-radius: var(--radius-full);
  background: var(--card-bg);
  border: 1.5px solid var(--card-border);
  color: var(--text-main);
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--trans-quick);
  white-space: nowrap;
}

.btn-game-action:hover {
  border-color: var(--primary-color);
  color: var(--primary-color);
}

.btn-game-action.active-tool {
  background: var(--primary-color);
  color: #FFFFFF;
  border-color: var(--primary-color);
}