/* learning.css */
.learning-settings {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-lg);
    margin-bottom: var(--space-lg);
    align-items: center;
    background: var(--bg-primary);
    padding: var(--space-lg);
    border-radius: var(--radius-lg);
}

.study-plan-state-card,
.study-plan-empty-card {
    box-sizing: border-box;
    width: 100%;
    min-height: 180px;
    border: 2px dashed var(--primary);
    border-radius: var(--radius-xl);
    background: linear-gradient(135deg, var(--bg-primary), rgba(255, 107, 53, 0.08));
}

.study-plan-state-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: var(--space-xl);
    color: var(--text-secondary);
    text-align: center;
}

.study-plan-state-card h4,
.study-plan-state-card p {
    margin: 0;
}

.study-plan-state-card h4 {
    color: var(--text-primary);
}

.study-plan-state-card--error {
    border-color: var(--danger);
    background: linear-gradient(135deg, var(--bg-primary), rgba(239, 68, 68, 0.08));
}

.study-plan-state-card--error > i {
    color: var(--danger);
    font-size: 1.75rem;
}

.study-plan-state-card__spinner {
    width: 32px;
    height: 32px;
    border: 3px solid rgba(255, 107, 53, 0.2);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: studyPlanStateSpin 0.8s linear infinite;
}

.study-plan-empty-card {
    appearance: none;
    display: flex;
    align-items: center;
    gap: var(--space-lg);
    padding: var(--space-xl);
    color: inherit;
    font: inherit;
    text-align: left;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.study-plan-empty-card:hover,
.study-plan-empty-card:focus-visible {
    transform: translateY(-2px);
    border-color: var(--primary-dark);
    box-shadow: var(--shadow-lg);
}

.study-plan-empty-card:focus-visible,
.study-plan-state-card__action:focus-visible {
    outline: 3px solid rgba(255, 107, 53, 0.28);
    outline-offset: 3px;
}

.study-plan-empty-card__icon {
    display: inline-flex;
    flex: 0 0 auto;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    font-size: 1.5rem;
    box-shadow: var(--shadow-md);
}

.study-plan-empty-card__body {
    display: flex;
    flex: 1;
    min-width: 0;
    flex-direction: column;
    gap: var(--space-sm);
}

.study-plan-empty-card__heading {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.study-plan-empty-card__heading strong {
    color: var(--text-primary);
    font-family: var(--font-display);
    font-size: 1.2rem;
}

.study-plan-empty-card__heading small {
    padding: 3px 9px;
    border-radius: var(--radius-full);
    background: rgba(255, 107, 53, 0.12);
    color: var(--primary-dark);
    font-weight: 700;
}

.study-plan-empty-card__description {
    color: var(--text-secondary);
    line-height: 1.6;
}

.study-plan-state-card__action,
.study-plan-empty-card__action {
    display: inline-flex;
    flex: 0 0 auto;
    align-items: center;
    justify-content: center;
    min-height: 44px;
    padding: var(--space-sm) var(--space-lg);
    border: 0;
    border-radius: var(--radius-full);
    appearance: none;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    font: inherit;
    font-weight: 700;
    text-align: center;
}

.study-plan-state-card__action {
    margin-top: var(--space-sm);
    cursor: pointer;
}

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

.setting-group {
    display: flex;
    align-items: center;
    gap: var(--space-md);
}

.setting-label {
    font-weight: 700;
    color: var(--text-secondary);
}

.setting-radio {
    display: flex;
    gap: var(--space-md);
}

.setting-radio label {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    cursor: pointer;
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--radius-full);
    transition: all 0.3s ease;
    border: 2px solid var(--border-color);
}

.setting-radio label:hover {
    border-color: var(--primary);
    background: rgba(255, 107, 53, 0.05);
}

.setting-radio input[type="radio"] {
    width: auto;
    accent-color: var(--primary);
}

.pronunciation-selector {
    display: flex;
    gap: var(--space-md);
    align-items: center;
    margin: var(--space-md) 0;
}

.pronunciation-option {
    padding: var(--space-md) var(--space-lg);
    border: 3px solid var(--border-color);
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.pronunciation-option:hover {
    border-color: var(--primary);
    background: rgba(255, 107, 53, 0.05);
}

.pronunciation-option.active {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    border-color: var(--primary);
    box-shadow: var(--shadow-md);
}

.spelling-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: var(--space-lg) 0;
}

.spelling-display {
    font-family: var(--font-display);
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: 4px;
    background: linear-gradient(135deg, var(--bg-primary), var(--bg-secondary));
    padding: var(--space-lg) var(--space-2xl);
    border-radius: var(--radius-lg);
    min-width: 350px;
    text-align: center;
    margin: var(--space-lg) 0;
    border: 3px solid var(--primary-light);
    box-shadow: var(--shadow-md);
    color: var(--text-primary);
}

.letter-tiles {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--space-md);
    margin: var(--space-lg) 0;
    max-width: 550px;
}

.letter-tile {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: white;
    font-family: var(--font-display);
    font-size: 1.6rem;
    font-weight: 800;
    border-radius: var(--radius-md);
    cursor: pointer;
    box-shadow: var(--shadow-md);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: none;
}

.letter-tile:hover {
    transform: translateY(-4px) scale(1.1);
    background: linear-gradient(135deg, var(--secondary), var(--secondary-dark));
    box-shadow: var(--shadow-lg);
}

.letter-tile:active {
    transform: scale(0.95);
}

.spelling-result {
    font-family: var(--font-display);
    font-size: 1.3rem;
    font-weight: 700;
    margin: var(--space-md) 0;
    min-height: 36px;
    text-align: center;
}

.spelling-controls {
    display: flex;
    gap: var(--space-md);
    margin-top: var(--space-lg);
    flex-wrap: wrap;
    justify-content: center;
}

.spelling-hint {
    background: linear-gradient(135deg, var(--accent-yellow), #FFF0A0);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    margin-top: var(--space-lg);
    text-align: center;
    display: none;
    box-shadow: var(--shadow-md);
    border: 2px solid var(--warning);
}


#wordCardModeModal .modal-content.word-card-mode {
    width: min(1100px, calc(100vw - 48px));
    max-width: 1100px;
    max-height: 96vh;
    padding: 24px 28px 28px;
}

.word-card-mode {
    max-width: 1100px;
}

#wordCardModeModal .modal-header {
    margin-bottom: var(--space-lg);
}

.word-card-mode-toolbar {
    display: flex;
    justify-content: flex-end;
    gap: var(--space-md);
    flex-wrap: wrap;
    margin-bottom: var(--space-md);
}

.word-card-unified-settings {
    position: relative;
    z-index: 2;
    display: grid;
    grid-template-columns: repeat(9, minmax(0, 1fr));
    gap: 10px;
    width: 100%;
    min-width: 0;
    margin-bottom: var(--space-md);
    padding: 12px;
    border: 1px solid rgba(148, 163, 184, 0.24);
    border-radius: 18px;
    background: #fff;
    box-shadow: 0 10px 28px rgba(15, 23, 42, 0.06);
}

.word-card-settings-toggle {
    display: none;
}

.word-card-unified-settings__row {
    display: contents;
}

.word-card-setting {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    padding: 6px 12px;
    font-weight: 600;
    color: var(--text-secondary);
}

.word-card-setting input {
    width: 70px;
    padding: 4px 6px;
    text-align: center;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
}

.word-card-unified-settings .word-card-setting {
    justify-content: center;
    width: 100%;
    min-width: 0;
    min-height: 46px;
    padding: 8px 10px;
    border: 0;
    border-radius: 0;
    background: transparent;
    font-size: 0.88rem;
    text-align: center;
}

.word-card-unified-settings .word-card-setting--number {
    gap: 6px;
}

.word-card-unified-settings .word-card-setting--number input {
    width: 48px;
    min-width: 0;
    padding: 4px;
}

.word-card-unified-settings .word-card-setting--toggle input {
    flex: 0 0 auto;
    width: auto;
    margin: 0;
    accent-color: var(--success);
}

.word-card-unified-settings .word-card-setting span {
    min-width: 0;
}

.word-card-stage {
    width: 100%;
    min-width: 0;
    padding: 10px;
    background: linear-gradient(135deg, #FFF7ED, #FFFDF8);
    border-radius: var(--radius-xl);
    border: 2px solid rgba(255, 107, 53, 0.2);
    margin-bottom: 10px;
}

.word-card-main {
    position: relative;
    background: #FFFDF6;
    border: 3px solid #1F2937;
    border-radius: 28px;
    padding: 40px 32px;
    min-height: 280px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    gap: var(--space-md);
    cursor: pointer;
    overflow: hidden;
}

.study-unified-word-card-mount {
    display: none;
    width: 100%;
    min-width: 0;
    text-align: left;
    cursor: default;
}

.study-unified-word-card-mount.is-active {
    display: block;
}

.word-card-main.has-unified-word-card {
    display: block;
    width: 100%;
    min-height: 0;
    padding: 40px 10px 10px;
    cursor: default;
    overflow: visible;
}

.word-card-main.has-unified-word-card > .word-card-audio,
.word-card-main.has-unified-word-card > .word-card-english,
.word-card-main.has-unified-word-card > .word-card-phonetic,
.word-card-main.has-unified-word-card > .word-card-hint,
.word-card-main.has-unified-word-card > .word-card-chinese,
.word-card-main.has-unified-word-card > .word-card-flip {
    display: none;
}

.word-card-main.has-unified-word-card .word-card-progress {
    z-index: 4;
}

#wordCardModeModal .study-unified-word-card-mount .unified-word-card,
#studySessionPage .study-unified-word-card-mount .unified-word-card {
    max-width: 100%;
}

.word-card-progress {
    position: absolute;
    top: 18px;
    left: 18px;
    padding: 4px 10px;
    font-weight: 700;
    font-size: 0.85rem;
    color: var(--text-secondary);
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid var(--border-color);
    border-radius: 999px;
}

.word-card-audio {
    position: absolute;
    top: 16px;
    right: 18px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    border: 2px solid #1F2937;
    background: #E7F7EF;
    color: #0F766E;
    font-size: 1.1rem;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.word-card-english {
    font-family: var(--font-display);
    font-size: 3rem;
    font-weight: 800;
    color: var(--text-primary);
}

.word-card-phonetic {
    font-size: 1.2rem;
    color: var(--text-muted);
    letter-spacing: 2px;
}

.word-card-hint {
    font-size: 0.95rem;
    color: var(--text-muted);
}

.word-card-chinese {
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--text-secondary);
    display: none;
}

.word-card-main.is-flipped .word-card-chinese {
    display: block;
}

.word-card-main.is-flipped .word-card-hint {
    display: none;
}

/* Keep legacy word details out of the unified-card presentation, even after flip rules run. */
.word-card-main.has-unified-word-card > .word-card-chinese,
.word-card-main.has-unified-word-card > .word-card-audio,
.word-card-main.has-unified-word-card > .word-card-english,
.word-card-main.has-unified-word-card > .word-card-phonetic,
.word-card-main.has-unified-word-card > .word-card-hint,
.word-card-main.has-unified-word-card > .word-card-flip {
    display: none !important;
}

.word-card-celebration-layer {
    position: absolute;
    inset: 0;
    overflow: hidden;
    pointer-events: none;
    z-index: 1;
}

.word-card-celebration-layer.is-active {
    filter: drop-shadow(0 10px 22px rgba(255, 107, 53, 0.24));
}

.word-card-praise-text {
    position: absolute;
    top: 28px;
    left: 50%;
    transform: translateX(-50%) translateY(-8px) scale(0.92);
    padding: 10px 18px;
    border-radius: 999px;
    background: linear-gradient(135deg, rgba(255, 107, 53, 0.96), rgba(245, 158, 11, 0.96));
    color: #fff;
    font-weight: 800;
    letter-spacing: 0.04em;
    box-shadow: 0 18px 40px rgba(255, 107, 53, 0.22);
    opacity: 0;
    pointer-events: none;
    z-index: 3;
    white-space: nowrap;
}

.word-card-praise-text.is-active {
    animation: wordCardPraisePop 0.95s ease forwards;
}

.word-card-particle {
    position: absolute;
    left: var(--x);
    top: 62%;
    width: 10px;
    height: 18px;
    border-radius: 999px;
    background: var(--color);
    transform: translate(-50%, -50%) rotate(var(--rotate));
    opacity: 0;
    animation: wordCardParticleBurst 0.9s ease-out forwards;
}

.word-card-flip {
    position: absolute;
    bottom: 18px;
    right: 18px;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 2px solid #1F2937;
    background: #F0FDF4;
    color: #15803D;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.word-card-celebration-layer.is-active {
    filter: drop-shadow(0 18px 34px rgba(255, 107, 53, 0.26));
}

.word-card-main.is-challenge-pop {
    animation: wordCardStagePulse 0.52s ease;
}

.word-card-main.is-challenge-critical {
    box-shadow: 0 0 0 4px rgba(245, 158, 11, 0.16), 0 28px 60px rgba(168, 85, 247, 0.18);
}

.word-card-praise-text {
    top: 22px;
    padding: 12px 20px;
    background: linear-gradient(135deg, rgba(255, 107, 53, 0.98), rgba(168, 85, 247, 0.95));
    box-shadow: 0 22px 46px rgba(255, 107, 53, 0.28);
}

.word-card-praise-text.is-active {
    animation: wordCardPraiseImpact 1.1s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
}

.word-card-particle {
    width: 12px;
    height: 22px;
    animation-duration: 1.05s;
}

.word-card-shockwave {
    position: absolute;
    left: 50%;
    top: 56%;
    width: 72px;
    height: 72px;
    border-radius: 50%;
    border: 3px solid rgba(255, 107, 53, 0.4);
    transform: translate(-50%, -50%) scale(0.35);
    opacity: 0;
    animation: wordCardShockwave 0.78s ease-out forwards;
}

.word-card-shockwave--critical,
.word-card-shockwave--legendary,
.word-card-shockwave--record {
    border-color: rgba(168, 85, 247, 0.45);
}

.word-card-medal {
    position: absolute;
    left: 50%;
    top: 34%;
    padding: 8px 14px;
    border-radius: 999px;
    font-size: 0.84rem;
    font-weight: 800;
    letter-spacing: 0.06em;
    color: #fff;
    background: linear-gradient(135deg, #ff6b35, #f59e0b);
    box-shadow: 0 18px 36px rgba(255, 107, 53, 0.22);
    transform: translate(-50%, -50%);
    opacity: 0;
    animation: wordCardMedalDrop 0.95s ease forwards;
}

.word-card-medal--record {
    background: linear-gradient(135deg, #0ea5e9, #2563eb);
}

.word-card-medal--legendary {
    background: linear-gradient(135deg, #8b5cf6, #d946ef);
}

.word-card-medal--critical {
    background: linear-gradient(135deg, #f97316, #ef4444);
}

.word-card-mode-toggles {
    display: flex;
    justify-content: center;
    gap: var(--space-xl);
    flex-wrap: wrap;
    padding: 12px var(--space-lg);
    border-radius: var(--radius-full);
    border: 2px dashed rgba(16, 185, 129, 0.4);
    background: rgba(16, 185, 129, 0.08);
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
}

.word-card-mode-toggles input {
    margin-right: var(--space-sm);
    accent-color: var(--success);
}

.word-card-challenge-toggle input {
    accent-color: #FF6B35;
}

.word-card-mode-actions {
    position: sticky;
    bottom: 0;
    z-index: 20;
    display: flex;
    justify-content: center;
    gap: var(--space-lg);
    flex-wrap: wrap;
    padding: 10px 4px;
    padding-bottom: calc(10px + env(safe-area-inset-bottom));
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.86), #fff 28%);
}

@keyframes wordCardPraisePop {
    0% {
        opacity: 0;
        transform: translateX(-50%) translateY(14px) scale(0.82);
    }
    22% {
        opacity: 1;
        transform: translateX(-50%) translateY(0) scale(1);
    }
    80% {
        opacity: 1;
        transform: translateX(-50%) translateY(-2px) scale(1.02);
    }
    100% {
        opacity: 0;
        transform: translateX(-50%) translateY(-18px) scale(0.95);
    }
}

@keyframes wordCardParticleBurst {
    0% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.35) rotate(var(--rotate));
    }
    12% {
        opacity: 1;
    }
    100% {
        opacity: 0;
        transform: translate(calc(-50% + var(--offset-x)), calc(-50% + var(--offset-y))) scale(1.08) rotate(calc(var(--rotate) + 120deg));
    }
}

@keyframes wordCardStagePulse {
    0% {
        transform: scale(0.98);
    }
    40% {
        transform: scale(1.02);
    }
    100% {
        transform: scale(1);
    }
}

@keyframes wordCardPraiseImpact {
    0% {
        opacity: 0;
        transform: translateX(-50%) translateY(20px) scale(0.76);
    }
    18% {
        opacity: 1;
        transform: translateX(-50%) translateY(0) scale(1.05);
    }
    78% {
        opacity: 1;
        transform: translateX(-50%) translateY(-4px) scale(1);
    }
    100% {
        opacity: 0;
        transform: translateX(-50%) translateY(-28px) scale(0.92);
    }
}

@keyframes wordCardShockwave {
    0% {
        opacity: 0.55;
        transform: translate(-50%, -50%) scale(0.35);
    }
    100% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(4.2);
    }
}

@keyframes wordCardMedalDrop {
    0% {
        opacity: 0;
        transform: translate(calc(-50% + var(--medal-x)), -36px) scale(0.7);
    }
    20% {
        opacity: 1;
        transform: translate(calc(-50% + var(--medal-x)), -6px) scale(1.04);
    }
    78% {
        opacity: 1;
        transform: translate(calc(-50% + var(--medal-x)), -2px) scale(1);
    }
    100% {
        opacity: 0;
        transform: translate(calc(-50% + var(--medal-x)), -26px) scale(0.94);
    }
}

@media (max-width: 768px) {
    #wordCardModeModal .modal-content.word-card-mode {
        width: min(96vw, 96vw);
        max-width: 96vw;
        max-height: 94vh;
        padding: 20px 18px 24px;
    }

    .word-card-mode {
        max-width: 95vw;
    }

    .word-card-english {
        font-size: 2.2rem;
    }

    .word-card-main {
        padding: 32px 20px;
        min-height: 240px;
    }

    .word-card-main.has-unified-word-card {
        padding: 40px 8px 8px;
        min-height: 0;
    }

    .word-card-settings-toggle {
        display: flex;
        align-items: center;
        justify-content: space-between;
        width: 100%;
        min-height: 46px;
        margin: 0 0 8px;
        padding: 10px 14px;
        border: 1px solid rgba(148, 163, 184, 0.28);
        border-radius: 14px;
        background: #fff;
        color: var(--text-primary);
        font: inherit;
        font-weight: 700;
        cursor: pointer;
        box-shadow: 0 8px 22px rgba(15, 23, 42, 0.05);
    }

    .word-card-settings-toggle__state {
        color: var(--primary);
        font-size: 0.82rem;
        font-weight: 700;
    }

    .word-card-unified-settings {
        display: none;
        grid-template-columns: 1fr;
        gap: 8px;
        padding: 8px;
        border-radius: 16px;
    }

    .word-card-unified-settings.is-expanded {
        display: grid;
    }

    .word-card-unified-settings__row {
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 6px;
    }

    .word-card-unified-settings .word-card-setting {
        flex-direction: column;
        gap: 5px;
        min-height: 58px;
        padding: 7px 4px;
        font-size: 0.78rem;
        line-height: 1.15;
    }

    .word-card-unified-settings .word-card-setting--toggle input {
        width: 18px;
        height: 18px;
    }

    .word-card-mode-actions {
        position: sticky;
        bottom: 0;
        z-index: 20;
        display: grid;
        grid-template-columns: repeat(4, minmax(0, 1fr));
        gap: 6px;
        margin-inline: -4px;
        padding: 10px 4px calc(10px + env(safe-area-inset-bottom));
        background: linear-gradient(180deg, rgba(255, 255, 255, 0.82), #fff 28%);
    }

    .word-card-mode-actions .btn {
        min-width: 0;
        padding: 10px 4px;
        font-size: 0.82rem;
        white-space: nowrap;
    }

    #wordCardModeModal .modal-content.word-card-mode {
        overflow-x: hidden;
        overflow-y: auto;
        overscroll-behavior: contain;
    }
}

@media (max-width: 600px) {
    .learning-settings {
        padding: var(--space-md);
    }

    .setting-group {
        width: 100%;
        flex-wrap: wrap;
    }

    .spelling-display {
        min-width: 0;
        width: min(100%, 320px);
        font-size: 1.8rem;
        letter-spacing: 2px;
        padding: var(--space-md) var(--space-lg);
    }

    .letter-tiles {
        gap: var(--space-sm);
    }

    .letter-tile {
        width: 44px;
        height: 44px;
        font-size: 1.2rem;
    }

    .pronunciation-option {
        padding: var(--space-sm) var(--space-md);
        font-size: 0.95rem;
    }

    .word-card-main {
        padding: 28px 18px;
        min-height: 220px;
    }

    .word-card-stage {
        padding: 8px;
    }

    .word-card-main.has-unified-word-card {
        padding-inline: 4px;
    }

    .word-card-praise-text {
        top: 20px;
        font-size: 0.92rem;
        max-width: calc(100% - 32px);
        white-space: normal;
    }

    .word-card-medal {
        font-size: 0.76rem;
        padding: 7px 12px;
    }

    .word-card-english {
        font-size: 1.9rem;
    }

    .word-card-chinese {
        font-size: 1.2rem;
    }
}

@media (max-width: 480px) {
    .study-plan-empty-card {
        flex-direction: column;
        align-items: center;
        padding: var(--space-lg);
        text-align: center;
    }

    .study-plan-empty-card__body,
    .study-plan-empty-card__heading {
        align-items: center;
    }

    .study-plan-empty-card__action {
        width: 100%;
        margin-inline: auto;
    }
}

@media (max-width: 420px) {
    .word-card-mode-actions .btn i {
        display: none;
    }
}

@media (max-width: 360px) {
    .spelling-display {
        font-size: 1.6rem;
    }

    .letter-tile {
        width: 40px;
        height: 40px;
        font-size: 1.1rem;
    }
}

@media (hover: none) {
    .letter-tile:hover,
    .pronunciation-option:hover {
        transform: none;
        box-shadow: var(--shadow-md);
    }
}
.study-spelling-panel { width: 100%; min-width: 0; box-sizing: border-box; margin: 24px auto; text-align: center; }
.study-spelling-panel[hidden] { display: none; }
.study-spelling-heading { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; color: #697687; }
.study-spelling-panel h2 { font-size: clamp(24px, 4vw, 36px); margin: 32px 0 16px; }
.study-spelling-panel input { display: block; box-sizing: border-box; width: 100%; max-width: 360px; margin: 36px auto; padding: 10px 16px; border: 2px solid #ff875f; border-radius: 20px; font-size: 24px; text-align: center; background: #fff; }
.study-spelling-panel input:focus { outline: 3px solid #16b99a35; border-color: #16b99a; }
.study-spelling-feedback { min-height: 48px; margin: 16px 0; overflow-wrap: anywhere; }
.study-spelling-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }
.study-spelling-stage { padding: clamp(24px, 5vw, 64px) clamp(16px, 4vw, 48px) 48px; border: 1px solid #dbe3ee; border-radius: 24px; background: linear-gradient(110deg, #fff9f0, #fff); box-shadow: 0 3px 12px #23375308; }
.study-spelling-audio { border: 0; background: transparent; cursor: pointer; padding: 12px 24px; color: #43516a; font: inherit; }
.study-spelling-audio i { display: block; color: #ff6935; font-size: 42px; margin-bottom: 16px; }
.study-spelling-audio span { font-weight: 600; }
.study-spelling-letters { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; }
.study-spelling-letters button { min-width: 44px; min-height: 44px; border: 0; border-radius: 12px; background: #fa622e; color: #fff; font-size: 22px; font-weight: 700; cursor: pointer; }
.study-spelling-letters button:disabled { opacity: .35; cursor: default; }
.study-spelling-stage button:focus-visible { outline: 3px solid #108b79; outline-offset: 3px; }
.study-spelling-hint { color: #526078; overflow-wrap: anywhere; }
.study-spelling-progress { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; margin-top: 22px; font-size: 14px; }
.study-plan-spelling-option { padding: 16px; margin: 16px 0; border: 1px solid #d8e9e4; border-radius: 12px; background: #f5fcf9; }
.study-plan-spelling-option label { display: flex; align-items: center; gap: 10px; font-weight: 700; cursor: pointer; }
.study-plan-spelling-option input { width: 18px; height: 18px; margin: 0; accent-color: #08aa82; }
.study-plan-spelling-option p { margin: 8px 0 0; color: #596778; font-size: 14px; }
#studySessionFlowGuide .study-flow-step[hidden] { display: none; }
@media (max-width: 600px) {
    .study-spelling-stage { padding: 24px 14px; }
    .study-spelling-letters { gap: 8px; }
    .study-spelling-actions { gap: 8px; }
    .study-spelling-actions .btn { padding: 12px 16px; min-height: 44px; }
}
#completeStudySessionButton[hidden] {
    display: none;
}