/* ── Tokens ── */
:root {
    --accent: #c0392b;
    --accent-muted: rgba(192, 57, 43, 0.1);
    --correct: #27ae60;
    --correct-muted: rgba(39, 174, 96, 0.1);
    --wrong: #c0392b;
    --wrong-muted: rgba(192, 57, 43, 0.1);
    --card-bg: #ffffff;
    --card-shadow: 0 2px 16px rgba(0,0,0,0.07);
    --radius: 0.75rem;
    --transition: 0.2s ease;
}

[data-theme="dark"] {
    --card-bg: #1e1e1e;
    --card-shadow: 0 2px 16px rgba(0,0,0,0.4);
}

/* ── Layout ── */
body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--pico-muted-border-color);
}

.site-title {
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--accent);
    letter-spacing: 0.05em;
}

a.site-title {
    text-decoration: none;
}

main.container {
    flex: 1;
    max-width: 600px;
    padding: 2rem 1rem;
}

/* ── Deck Selection ── */
#deck-selection h1 {
    margin-bottom: 0.25rem;
}

.subtitle {
    color: var(--pico-muted-color);
    margin-bottom: 2rem;
}

#deck-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

#deck-list button {
    color: var(--pico-contrast);
    width: 100%;
    text-align: left;
    padding: 1rem 1.25rem;
    border-radius: var(--radius);
    border: 1px solid var(--pico-muted-border-color);
    background: var(--card-bg);
    cursor: pointer;
    transition: border-color var(--transition), box-shadow var(--transition);
    font-size: 1rem;
}

#deck-list button:hover {
    border-color: var(--accent);
    box-shadow: var(--card-shadow);
}

/* ── Session Header ── */
#session-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
}

.progress-text {
    font-size: 0.9rem;
    color: var(--pico-muted-color);
}

.icon-button {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--pico-muted-color);
    font-size: 0.9rem;
    padding: 0.4rem 0.75rem;
    border-radius: var(--radius);
    transition: color var(--transition), background var(--transition);
}

.icon-button:hover {
    color: var(--accent);
    background: var(--accent-muted);
}

/* ── Card ── */
.card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--card-shadow);
    padding: 3rem 2rem;
    text-align: center;
    margin-bottom: 2rem;
    min-height: 220px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    transition: opacity var(--transition);
}

#card-japanese {
    font-size: 4rem;
    line-height: 1.2;
    margin-bottom: 0.5rem;
}

.card-romaji {
    font-size: 1.1rem;
    color: var(--pico-muted-color);
    margin-bottom: 0.5rem;
    letter-spacing: 0.05em;
}

.card-english {
    font-size: 1.8rem;
    font-weight: 500;
    margin-top: 1rem;
}

/* ── Action Area ── */
#action-area {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.action-button {
    width: 100%;
    padding: 1rem;
    font-size: 1rem;
    border-radius: var(--radius);
    border: none;
    cursor: pointer;
    transition: opacity var(--transition), transform var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
}

.action-button:hover {
    opacity: 0.85;
    transform: translateY(-1px);
}

.answer-buttons {
    display: flex;
    gap: 1rem;
    width: 100%;
}

.answer-buttons .action-button {
    flex: 1;
}

.correct-button {
    background: var(--correct-muted);
    color: var(--correct);
    border: 1px solid var(--correct);
}

.wrong-button {
    background: var(--wrong-muted);
    color: var(--wrong);
    border: 1px solid var(--wrong);
}

#show-answer-button {
    background: var(--accent-muted);
    color: var(--accent);
    border: 1px solid var(--accent);
}

kbd {
    font-size: 0.75rem;
    padding: 0.15rem 0.4rem;
    border-radius: 0.25rem;
    border: 1px solid currentColor;
    opacity: 0.6;
}

/* ── Complete ── */
.complete {
    text-align: center;
    padding: 2rem;
}

.complete p:first-child {
    font-size: 3rem;
    margin-bottom: 0.5rem;
}

.complete-stats {
    color: var(--pico-muted-color);
    margin-bottom: 2rem;
}

/* ── Overlay ── */
.overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 100;
    padding: 1rem;
}

.overlay-box {
    background: var(--pico-background-color);
    border-radius: var(--radius);
    padding: 1.5rem;
    width: 100%;
    max-width: 480px;
    max-height: 80vh;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.overlay-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.overlay-header h3 {
    margin: 0;
}

.overlay-hint {
    font-size: 0.85rem;
    color: var(--pico-muted-color);
    margin: 0;
}

#manage-deck-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    max-height: 40vh;
    overflow-y: auto;
}

.deck-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--pico-muted-border-color);
    font-size: 0.95rem;
}

.deck-item input[type="checkbox"] {
    width: 1.1rem;
    height: 1.1rem;
    accent-color: var(--accent);
    cursor: pointer;
}

/* ── Segment Control ── */
.segment-control {
    display: flex;
    border: 1px solid var(--pico-muted-border-color);
    border-radius: var(--radius);
    overflow: hidden;
    margin-bottom: 1.5rem;
    width: fit-content;
}

.segment {
    background: none;
    border: none;
    padding: 0.5rem 1.5rem;
    cursor: pointer;
    color: var(--pico-muted-color);
    font-size: 0.95rem;
    transition: background var(--transition), color var(--transition);
}

.segment.active {
    background: var(--accent);
    color: white;
}

/* ── Endless Options ── */
#endless-options {
    margin-bottom: 1.5rem;
}

#endless-options label {
    display: block;
    font-size: 0.85rem;
    color: var(--pico-muted-color);
    margin-bottom: 0.4rem;
}

#timer-input {
    width: 12rem;
    padding: 0.5rem 0.75rem;
    border-radius: var(--radius);
    border: 1px solid var(--pico-muted-border-color);
    background: var(--card-bg);
    color: var(--pico-color);
    font-size: 1rem;
}

/* ── Session Status ── */
#session-status {
    display: flex;
    align-items: center;
}

#timer-display {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--accent);
    letter-spacing: 0.05em;
}

#timer-display.warning {
    color: var(--wrong);
    animation: pulse 1s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

/* ── Theme Toggle ── */
.theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.2rem;
    padding: 0.25rem;
    line-height: 1;
}

/* ── Utility ── */
.hidden {
    display: none !important;
}

/* ── Mobile ── */
@media (max-width: 480px) {
    #card-japanese {
        font-size: 3rem;
    }

    .card-english {
        font-size: 1.4rem;
    }

    .action-button {
        padding: 1.1rem;
    }

    kbd {
        display: none;
    }
}