html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Arial, sans-serif;
  background: #222;
  overflow: hidden;
}

* {
  box-sizing: border-box;
}

#flagCanvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw !important;
  height: 100vh !important;
  min-width: 100vw;
  min-height: 100vh;
  max-width: 100vw;
  max-height: 100vh;
  display: block;
  border: none;
  background: #222;
  z-index: 1;
  /* Cải thiện rendering trên mobile */
  -webkit-transform: translateZ(0);
  transform: translateZ(0);
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
}

body {
  /* Xóa width/height cũ, chỉ giữ ở html */
  -webkit-overflow-scrolling: touch;
  overscroll-behavior: none;
}

.controls {
  position: absolute;
  background: rgba(255, 255, 255, 0.92);
  border-radius: 16px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  z-index: 10;
}

.controls-right {
  top: 18px;
  right: 18px;
  padding: 10px 12px 8px 12px;
  min-width: 120px;
}

.controls-left {
  top: 18px;
  left: 18px;
  padding: 14px 16px 12px 16px;
  min-width: 160px;
}

.settings-panel {
  position: absolute;
  top: 66px;
  right: 18px;
  background: rgba(255, 255, 255, 0.96);
  border-radius: 14px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
  padding: 12px 14px 10px 14px;
  min-width: 160px;
  max-width: 260px;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  z-index: 20;
  transition: opacity 0.2s, visibility 0.2s;
}

.settings-panel.hide {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.settings-toggle {
  position: absolute;
  top: 18px;
  right: 18px;
  background: rgba(255, 255, 255, 0.96);
  border: none;
  border-radius: 10px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.13);
  min-width: 120px;
  height: 38px;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 8px;
  cursor: pointer;
  z-index: 30;
  padding: 0 14px;
  transition: background 0.2s;
  /* Tắt highlight trên mobile */
  -webkit-tap-highlight-color: transparent;
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  user-select: none;
}

.settings-toggle:hover {
  background: #f5f5f5;
}

.settings-icon {
  font-size: 1.25rem;
  color: #c62828;
}

.settings-title {
  font-size: 1rem;
  color: #c62828;
  font-weight: 700;
  letter-spacing: 1px;
}

.settings-arrow {
  font-size: 1.1rem;
  color: #c62828;
  margin-left: auto;
  transition: transform 0.2s;
}

.settings-toggle.open .settings-arrow {
  transform: rotate(180deg);
}

.settingsToggle h3 {
  margin: 0 0 10px 0;
  font-size: 1.02rem;
  color: #c62828;
  font-weight: 700;
  letter-spacing: 1px;
  text-align: left;
}

.controls-item {
  display: flex;
  flex-direction: column;
  margin-bottom: 10px;
}

.controls-item:last-child {
  margin-bottom: 0;
}

label {
  font-size: 0.92rem;
  font-weight: 600;
  color: #c62828;
  margin-bottom: 5px;
  letter-spacing: 0.5px;
}

input[type="range"] {
  width: 100%;
  accent-color: #c62828;
  margin-bottom: 0;
  height: 20px;
}

select {
  width: 100%;
  margin-bottom: 0;
  padding: 5px 7px;
  font-size: 0.92rem;
  border-radius: 6px;
  border: 1px solid #c62828;
  background: #fff;
  color: #c62828;
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
}

button#playMusicBtn {
  padding: 7px 12px;
  font-size: 0.92rem;
  background: #c62828;
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 600;
  transition: background 0.2s;
  -webkit-tap-highlight-color: transparent;
}

button#playMusicBtn:hover {
  background: #b71c1c;
}

.music-controls {
  display: flex;
  gap: 8px;
  justify-content: center;
  align-items: center;
}

#prevMusicBtn,
#nextMusicBtn {
  padding: 7px 10px;
  font-size: 1rem;
  background: #e0e0e0;
  color: #c62828;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 600;
  transition: background 0.2s;
  -webkit-tap-highlight-color: transparent;
}

#prevMusicBtn:hover,
#nextMusicBtn:hover {
  background: #ffcdd2;
}

audio {
  width: 100%;
  margin-top: 2px;
}

/* Mobile responsive */
@media (max-width: 600px) {
  html,
  body {
    height: 100%;
    overflow: hidden;
  }
  #flagCanvas {
    width: 100vw !important;
    height: 100vh !important;
    min-width: 100vw;
    min-height: 100vh;
    max-width: 100vw;
    max-height: 100vh;
  }
  .settings-panel {
    left: 0;
    right: 0;
    width: 100vw;
    min-width: 0;
    max-width: 100vw;
    padding: 12px 4vw 8px 4vw;
  }
  .settings-toggle {
    padding: 0 4vw;
  }

  .settings-title {
    font-size: 1.1rem;
  }

  .settings-icon {
    font-size: 1.4rem;
  }

  .controls-item {
    margin-bottom: 12px;
  }

  label,
  select,
  button#playMusicBtn {
    font-size: 1.1rem;
  }

  input[type="range"] {
    height: 36px;
  }

  input[type="range"]::-webkit-slider-track {
    background: #ddd;
    height: 8px;
    border-radius: 4px;
  }

  input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    background: #c62828;
    height: 24px;
    width: 24px;
    border-radius: 50%;
    cursor: pointer;
    margin-top: -8px;
  }

  input[type="range"]::-moz-range-track {
    background: #ddd;
    height: 8px;
    border-radius: 4px;
    border: none;
  }

  input[type="range"]::-moz-range-thumb {
    background: #c62828;
    height: 24px;
    width: 24px;
    border-radius: 50%;
    border: none;
    cursor: pointer;
  }

  button#playMusicBtn {
    padding: 12px 16px;
    font-size: 1.1rem;
    min-height: 44px;
  }

  #prevMusicBtn,
  #nextMusicBtn {
    padding: 10px 12px;
    font-size: 1.2rem;
    min-height: 44px;
    min-width: 44px;
  }

  audio {
    margin-top: 8px;
    height: 44px;
  }
}

/* Landscape mobile */
@media (max-width: 900px) and (orientation: landscape) {
  .settings-toggle {
    height: 36px;
  }

  .settings-panel {
    top: 44px;
    right: 4px;
    left: 4px;
    padding: 8px;
  }

  .controls-item {
    margin-bottom: 6px;
  }

  label {
    font-size: 0.9rem;
    margin-bottom: 2px;
  }

  input[type="range"] {
    height: 24px;
  }

  button#playMusicBtn {
    padding: 6px 12px;
    font-size: 0.9rem;
    min-height: 32px;
  }

  #prevMusicBtn,
  #nextMusicBtn {
    padding: 6px 8px;
    font-size: 1rem;
    min-height: 32px;
    min-width: 32px;
  }
}