@media (max-width: 780px) {
      :root {
/* File: css/responsive.css
   Purpose: Responsive overrides for all scenes and minigames.
*/
        --minigame-left: 8px;
        --minigame-right: 8px;
        --minigame-top: 98px;
        --minigame-bottom: 194px;
        --minigame-padding: 8px;
      }

      .status-panel {
        top: 52px;
        left: 10px;
        right: 10px;
        min-width: 0;
      }

      .live-field {
        flex: 1;
        min-height: 92px;
      }

      .live-cast-lane {
        height: 72px;
      }

      .live-cast {
        width: 64px;
        height: 64px;
      }

      .voice {
        font-size: 0.78rem;
        min-width: 108px;
        padding: 9px 11px;
      }

      .bass-quiz-card {
        grid-template-columns: 20px 1fr;
        gap: 8px;
        padding: 8px;
      }

      .bass-question-text {
        font-size: 1rem;
        min-height: 2.8em;
      }

      .bass-options {
        grid-template-columns: 1fr;
        gap: 7px;
      }

      .bass-option {
        min-height: 46px;
        padding: 8px 10px;
        font-size: 0.82rem;
      }

      .chase-canvas {
        max-height: calc(100% - 110px);
      }

      .chase-actions {
        grid-template-columns: repeat(3, minmax(0, 1fr));
      }

      .drum-canvas {
        max-height: calc(100% - 92px);
      }

      .drum-actions {
        grid-template-columns: repeat(3, minmax(0, 1fr));
      }

      .drum-power-panel {
        left: 148px;
        right: 8px;
        bottom: 8px;
        gap: 6px;
      }

      .drum-dash-gauge {
        right: 8px;
        width: 170px;
        bottom: 36px;
      }

      .drum-hp-gauge {
        right: 8px;
        width: 170px;
        bottom: 64px;
      }

      .drum-power-slot {
        min-width: 56px;
        font-size: 9px;
        padding: 0 4px;
      }

      .guitar-brief {
        inset: 52px 10px 58px;
        padding: 12px 12px 10px;
      }

      .guitar-brief-title {
        margin-bottom: 9px;
      }

      .guitar-brief-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 8px;
        margin-bottom: 9px;
      }

      .guitar-brief-card {
        min-height: 0;
      }

      .guitar-brief-start {
        min-width: 0;
        width: 100%;
      }

      /* Bass / Live / Drum のブリーフィングもギターと同様に小画面向けへ圧縮する。
         3カラムのままだとスマホでは1列が細くなりすぎ、折り返しで縦に伸びてしまう。 */
      .bass-brief,
      .live-brief,
      .drum-brief {
        inset: 52px 10px 58px;
        padding: 12px 12px 10px;
      }

      .bass-brief-grid,
      .live-brief-grid,
      .drum-brief-grid {
        grid-template-columns: 1fr;
        gap: 8px;
        margin-bottom: 9px;
      }

      .bass-brief-card,
      .live-brief-card,
      .drum-brief-card {
        min-height: 0;
      }

      /* 小画面は1カラム表示になるため、幅の指定を解除する。 */
      .live-brief-card-wide {
        grid-column: auto;
      }

      .top-ui {
        top: 132px;
        right: 10px;
        gap: 6px;
      }

      .mini-btn {
        padding: 7px 10px;
        font-size: 0.7rem;
      }

      .stage-hud {
        top: 10px;
        left: 10px;
        right: 10px;
        min-width: 0;
        width: auto;
        font-size: 0.72rem;
        padding: 8px 10px;
      }

      .title-wrap {
        grid-template-columns: 1fr;
        gap: 22px;
        padding-top: 5vh;
      }

      .menu-panel {
        max-width: 430px;
      }

      .chara {
        width: min(56vw, 270px);
        /* bottom は base.css の calc(var(--textbox-h) + 14px) を継続使用する。
           このブレークポイントでは .textbox の min-height が176pxに変わるが、
           --textbox-h はJSが実測して更新するため個別指定は不要。 */
      }

      .textbox {
        min-height: 176px;
      }

      .dialog {
        line-height: 1.56;
      }
    }

    @media (max-height: 520px) and (orientation: landscape) {
      :root {
        --minigame-left: 8px;
        --minigame-right: 8px;
        --minigame-top: 8px;
        --minigame-bottom: 8px;
        --minigame-padding: 7px;
      }

      .top-ui {
        top: 8px;
        right: 8px;
      }

      .mini-btn {
        padding: 5px 8px;
        font-size: 0.66rem;
      }

      .stage-hud {
        top: 8px;
        left: 8px;
        right: 126px;
        min-width: 0;
        width: auto;
        font-size: 0.64rem;
        padding: 6px 8px;
      }

      .status-panel {
        top: 46px;
        left: 8px;
        width: 168px;
        min-width: 0;
        padding: 6px 8px;
      }

      .status-title {
        font-size: 0.64rem;
        margin-bottom: 4px;
      }

      .status-row {
        grid-template-columns: 58px 1fr;
        font-size: 0.62rem;
        margin-bottom: 1px;
      }

      .status-stars {
        font-size: 0.76rem;
      }

      .live-head {
        gap: 5px;
        margin-bottom: 5px;
        font-size: 0.7rem;
      }

      .live-chip {
        padding: 3px 6px;
      }

      .live-note {
        font-size: 0.68rem;
        margin-bottom: 5px;
      }

      .live-controls {
        grid-template-columns: 1fr 1fr;
        gap: 5px;
        margin-bottom: 5px;
      }

      .live-select {
        grid-column: 1 / -1;
      }

      .live-select,
      .live-start {
        padding: 5px 8px;
        font-size: 0.72rem;
      }

      .live-field {
        flex: 1;
        min-height: 74px;
      }

      .live-cast-lane {
        height: 64px;
      }

      .live-cast {
        width: 54px;
        height: 54px;
        top: 0;
        bottom: auto;
      }

      .voice {
        font-size: 0.68rem;
        min-width: 98px;
        padding: 8px 10px;
      }

      .bass-head {
        gap: 5px;
      }

      .bass-quiz-card {
        grid-template-columns: 16px 1fr;
        gap: 6px;
        padding: 6px;
      }

      .bass-question-title {
        font-size: 0.64rem;
        margin-bottom: 5px;
      }

      .bass-question-text {
        margin-bottom: 8px;
        font-size: 0.82rem;
        line-height: 1.42;
        min-height: 2.4em;
      }

      .bass-options {
        gap: 5px;
      }

      .bass-option {
        min-height: 34px;
        padding: 6px 8px;
        font-size: 0.68rem;
      }

      .chase-head {
        gap: 5px;
        margin-bottom: 5px;
      }

      .chase-canvas {
        max-height: calc(100% - 72px);
      }

      .chase-actions {
        gap: 5px;
        margin-top: 5px;
        grid-template-columns: repeat(3, minmax(0, 1fr));
      }

      .drum-head {
        gap: 5px;
      }

      .drum-canvas {
        max-height: calc(100% - 70px);
      }

      .drum-actions {
        gap: 5px;
        margin-top: 5px;
        grid-template-columns: repeat(3, minmax(0, 1fr));
      }

      .drum-power-panel {
        left: 138px;
        right: 8px;
        bottom: 8px;
        gap: 5px;
      }

      .drum-dash-gauge {
        right: 8px;
        width: 150px;
        bottom: 34px;
      }

      .drum-hp-gauge {
        right: 8px;
        width: 150px;
        bottom: 60px;
      }

      .drum-power-slot {
        min-width: 50px;
        font-size: 8px;
        padding: 0 3px;
      }

      .guitar-brief {
        inset: 30px 8px 44px;
        padding: 9px 10px 8px;
      }

      .guitar-brief-title {
        font-size: 0.82rem;
        margin-bottom: 6px;
      }

      .guitar-brief-grid {
        gap: 5px;
        margin-bottom: 6px;
      }

      .guitar-brief-card {
        padding: 7px 8px 6px;
      }

      .guitar-brief-card p {
        font-size: 10px;
      }

      .guitar-brief-start {
        padding: 6px 10px;
        font-size: 0.68rem;
      }

      /* 横向きで高さの低い端末では Bass / Live / Drum も同様に圧縮する。 */
      .bass-brief,
      .live-brief,
      .drum-brief {
        inset: 30px 8px 44px;
        padding: 9px 10px 8px;
      }

      .bass-brief-title,
      .live-brief-title,
      .drum-brief-title {
        font-size: 0.82rem;
        margin-bottom: 6px;
      }

      .bass-brief-grid,
      .live-brief-grid,
      .drum-brief-grid {
        gap: 5px;
        margin-bottom: 6px;
      }

      .bass-brief-card,
      .live-brief-card,
      .drum-brief-card {
        padding: 7px 8px 6px;
      }

      .bass-brief-card p,
      .live-brief-card p,
      .drum-brief-card p {
        font-size: 10px;
      }

      .textbox-wrap {
        padding: 0;
      }

      .textbox {
        min-height: 112px;
        padding: 12px 12px 10px;
      }

      .name-tag {
        margin-top: -24px;
      }
    }

    @media (max-width: 932px) and (max-height: 430px) and (orientation: landscape) {
      :root {
        --minigame-padding: 5px;
      }

      .bass-quiz-card {
        padding: 5px;
      }

      .bass-option {
        min-height: 30px;
        font-size: 0.64rem;
      }

      .live-head {
        margin-bottom: 4px;
        font-size: 0.64rem;
        gap: 4px;
      }

      .live-chip {
        padding: 2px 5px;
      }

      .mood-wrap {
        margin-bottom: 4px;
        gap: 5px;
      }

      .mood-label {
        font-size: 0.64rem;
      }

      .live-note {
        font-size: 0.62rem;
        margin-bottom: 4px;
      }

      .live-controls {
        grid-template-columns: 1fr 1fr;
        margin-bottom: 4px;
        gap: 4px;
      }

      .live-select {
        grid-column: 1 / -1;
      }

      .live-select,
      .live-start {
        padding: 4px 6px;
        font-size: 0.66rem;
      }

      .live-field {
        flex: 1;
        min-height: 64px;
      }

      .live-cast-lane {
        height: 56px;
      }

      .live-cast {
        width: 44px;
        height: 44px;
        top: 0;
        bottom: auto;
      }
    }