/* ============= FONTS ============= */
.noto-xs {
    font-family: "Noto Sans JP", sans-serif;
    font-optical-sizing: auto;
    font-weight: 100;
    font-style: normal;
}

.noto-s {
    font-family: "Noto Sans JP", sans-serif;
    font-optical-sizing: auto;
    font-weight: 300;
    font-style: normal;
}

.noto-xl {
    font-family: "Noto Sans JP", sans-serif;
    font-optical-sizing: auto;
    font-weight: 900;
    font-style: normal;
}

/* ============= PERSPECTIVE ============= */
.perspective-1000 {
    perspective: 1000px;
}

/* ============= CARD FLIP ============= */
#gameCard {
    transform-style: preserve-3d;
    transition: transform 0.6s ease-in-out;
    position: relative;
    width: 100%;
    min-height: 24rem;
}

#gameCard.flipped {
    transform: rotateY(180deg);
}

/* Card faces - both absolutely positioned */
.card-face {
    position: absolute !important;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
}

.card-front {
    transform: rotateY(0deg);
}

.card-back {
    transform: rotateY(180deg);
}

#cardFront {
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
}

#cardBack {
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
}

/* ============= STRIKE ANIMATION ============= */
@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-10px); }
    75% { transform: translateX(10px); }
}

#gameCard.strike {
    animation: shake 0.4s ease-in-out;
}

#gameCard.strike.strike-1 {
    animation: shake 0.4s ease-in-out 1;
}

#gameCard.strike.strike-2 {
    animation: shake 0.4s ease-in-out 2;
}

/* ============= STRIKE INDICATORS ============= */
.strike-filled {
    background-color: #f87171 !important;
    border-color: #ef4444 !important;
}

/* ============= KANA BUTTON STYLES ============= */
.kana-btn {
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid #fbbf24;
    border-radius: 0.5rem;
    font-size: 4rem;
    font-weight: 900;
    cursor: pointer;
    transition: all 0.2s ease;
    background-color: #fef3c7;
    color: #1f2937;
    user-select: none;
    min-height: 70px;
    font-family: "Noto Sans JP", sans-serif;
}

.kana-btn:hover {
    border-color: #f59e0b;
    background-color: #fcd34d;
    transform: scale(1.05);
}

.kana-btn:active {
    transform: scale(0.95);
}

.kana-btn.disabled {
    opacity: 0.5;
    cursor: not-allowed;
    border-color: #d1d5db;
    background-color: #f3f4f6;
}

/* ============= SELECTION BUTTONS ============= */
#undoBtn, #doneBtn {
    font-weight: 300;
    transition: all 0.2s ease;
}

#undoBtn {
    background-color: #ffffff;
    color: #6b7280;
    border-color: #e5e7eb;
}

#undoBtn:hover:not(:disabled) {
    border-color: #fbbf24;
    background-color: #fef3c7;
    color: #b45309;
}

#undoBtn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

#doneBtn {
    background-color: #1f2937;
    color: #ffffff;
    border-color: #1f2937;
}

#doneBtn:hover {
    border-color: #f59e0b;
    background-color: #f59e0b;
    color: #1f2937;
}

#doneBtn:active {
    transform: scale(0.9);
}

/* ============= SELECTION BOXES CONTAINER ============= */
#selectionBoxes {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.selection-box {
    width: 60px;
    height: 60px;
    border: 2px solid #e5e7eb;
    border-radius: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 300;
    background-color: #ffffff;
    color: #1f2937;
    font-family: "Noto Sans JP", sans-serif;
}

.selection-box.filled {
    border-color: #fbbf24;
    background-color: #fef3c7;
}

@media (max-width: 640px) {
    .selection-box {
        width: 50px;
        height: 50px;
        font-size: 1.25rem;
    }
}

/* ============= ICON BUTTONS ============= */
#speakWordBtn, #speakCharBtn, #speakSentenceBtn {
    background-color: #ffffff;
    color: #6b7280;
    transition: all 0.2s ease;
}

#speakWordBtn:hover, #speakCharBtn:hover, #speakSentenceBtn:hover {
    border-color: #fbbf24 !important;
    background-color: #fef3c7;
    color: #b45309;
}

#speakWordBtn:active, #speakCharBtn:active, #speakSentenceBtn:active {
    transform: scale(0.9);
}

/* ============= SENTENCE HIGHLIGHTING ============= */
.highlight {
    background-color: #fef3c7;
    color: #1f2937;
    padding: 0.125rem 0.25rem;
    border-radius: 0.25rem;
    font-weight: 500;
}

/* ============= TOP BAR ============= */
.sticky {
    z-index: 40;
}

/* ============= GAME CARD ADJUSTMENT ============= */
#gameCard {
    padding-left: 0;
    padding-right: 1rem;
}

/* ============= CATEGORY CARD ============= */
.category-card {
    border: 1px solid #e5e7eb;
    border-radius: 0.5rem;
    padding: 1.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    background-color: #ffffff;
    position: relative;
}

.category-card:hover {
    border-color: #fbbf24;
    box-shadow: 0 0 0 3px rgba(251, 191, 36, 0.1);
    transform: translateY(-2px);
}

.category-card:active {
    transform: scale(0.98);
}

.category-name {
    font-size: 1.125rem;
    font-weight: 300;
    color: #111827;
    margin-bottom: 0.5rem;
    text-transform: capitalize;
}

.category-count {
    font-size: 0.875rem;
    color: #9ca3af;
    font-weight: 300;
}

.category-type {
    position: absolute;
    top: 1rem;
    right: 1rem;
    font-size: 0.75rem;
    uppercase;
    tracking-wider;
    padding: 0.25rem 0.75rem;
    background-color: #fef3c7;
    color: #b45309;
    border-radius: 9999px;
    font-weight: 300;
}

.review-badge {
    position: absolute;
    top: 0.75rem;
    right: 0.75rem;
    background-color: #fca5a5;
    color: #7f1d1d;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
    uppercase;
}

/* ============= CARD BACK STYLING ============= */
#cardBack {
    background-color: #1f2937 !important;
    border: 1px solid #374151 !important;
}

#answerText {
    word-break: break-all;
}

#answerKana {
    min-height: 1.75rem;
}

/* ============= ANIMATIONS ============= */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

#gameScreen {
    animation: fadeIn 0.3s ease-out;
}

#resultsScreen {
    animation: slideUp 0.5s ease-out;
}

/* ============= SELECTION DISPLAY ============= */
#selectionDisplay {
    min-height: 3rem;
    display: flex;
    align-items: center;
    justify-content: center;
    word-break: break-all;
    text-align: center;
}

/* ============= NOTIFICATION ============= */
#notification {
    transition: opacity 0.3s ease-in-out;
}

#notification.show {
    opacity: 1 !important;
    pointer-events: auto;
}

/* ============= RESPONSIVE ============= */
@media (max-width: 640px) {
    .noto-xl {
        font-size: 3rem;
    }

    .kana-btn {
        min-height: 50px;
        font-size: 1.1rem;
    }

    #gameCard {
        min-height: 350px;
    }

    .category-card {
        padding: 1rem;
    }
}

/* ============= UTILITY ============= */
.opacity-0 {
    opacity: 0;
}

.opacity-100 {
    opacity: 1;
}

.transition-opacity {
    transition-property: opacity;
    transition-duration: 300ms;
}

/* ============= CUSTOM COLORS ============= */
:root {
    --amber-50: #fffbeb;
    --amber-100: #fef3c7;
    --amber-400: #fbbf24;
    --amber-500: #f59e0b;
    --red-50: #fef2f2;
    --red-400: #f87171;
}

/* ============= LOADING STATE ============= */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

/* ============= ERROR STATE ============= */
.error {
    border-color: #ef4444 !important;
    background-color: #fef2f2 !important;
}

.error-text {
    color: #dc2626;
    font-size: 0.875rem;
    margin-top: 0.5rem;
}