:root {
    /* Colors */
    --bg: #0d0d0f;
    --surface: #16161a;
    --card: #1e1e24;
    --border: #2a2a35;
    --accent: #f0c040;
    --text: #f0ede8;
    --muted: #7a7a8a;
    --success: #4caf7d;
    --error: #e05c5c;

    /* Fonts */
    --primaryFont: 'DM Mono', monospace;
    --titleFont: 'Playfair Display', serif;
}

/* Color classes */
.skip {color: var(--accent)  !important}
.good {color: var(--success) !important}
.bad  {color: var(--error)   !important}

/* Shared pill button style */
.pill {
    font-family: var(--primaryFont);
    font-size: 0.72rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    padding: 0.5rem 1rem;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--muted);
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s;
}

* {
    /* Include borders for all measurements */
    box-sizing: border-box;
    margin: 0;
    padding: 0;

    /* Disable all highlighting/selection */
    user-select: none;
}

body {
    background: var(--bg);
    color: var(--text);
    font-family: var(--primaryFont);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    overflow-x: hidden;
}

/* Noise texture overlay */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg width='512' height='512' viewBox='0 0 512 512' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.75' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.04'/%3E%3C/svg%3E");
    background-size: 256px 256px;
    pointer-events: none;
}

header {
    width: 100%;
    padding: 2rem 1rem 1rem;
    display: flex;
    gap: 1rem;
    border-bottom: 1px solid var(--border);

    #headerTitle {
        display: flex;
        flex-wrap: wrap;
        align-items: baseline;
        gap: 1rem;
        /* Make the tagline disappear on smaller devices */
        max-height: calc(1.8rem * 1.2); /* logo font-size * line height */
        overflow: hidden;

        #logo {
            font-family: var(--titleFont);
            font-size: 1.8rem;
            font-weight: 900;
            letter-spacing: -0.02em;
            color: var(--text);
            flex-shrink: 0;

            span {
                color: var(--accent);
            }
        }

        #tagline {
            font-family: var(--primaryFont);
            font-size: 0.7rem;
            color: var(--muted);
            letter-spacing: 0.15em;
            text-transform: uppercase;
            white-space: nowrap;
        }
    }

    #settingsToggle {
        margin-left: auto;
        flex-shrink: 0;

        &:hover {
            border-color: var(--accent);
            color: var(--accent);
        }

        &.active {
            background: var(--accent);
            border-color: var(--accent);
            color: var(--bg);
        }
    }
}

/* Mode selector */
#modeBar {
    display: flex;
    gap: 0.5rem;
    padding: 1.5rem 1rem 0;
    width: 100%;
    flex-wrap: wrap;

    button {
        &.active {
            background: var(--accent);
            border-color: var(--accent);
            color: var(--bg);
            pointer-events: none;
        }

        &:not(.active):hover {
            border-color: var(--accent);
            color: var(--accent);
            cursor: pointer;
        }
    }
}

/* Settings panel */

#settingsPanel {
    width: 100%;
    padding: 1rem 1rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    flex-wrap: wrap;
    align-items: flex-end;
    gap: 1rem;
    animation: slideDown 0.2s ease;

    &.hidden {
        display: none;
    }
}

@keyframes slideDown {
    from {
        opacity: 0;
        translate: 0 -15px;
    }
}

.settingsGroup {
    width: 100%;
    min-width: 200px;
}

.settingsLabel {
    display: flex;
    justify-content: space-between;
    font-family: var(--primaryFont);
    font-size: 0.6rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--muted);
    margin-bottom: 0.75rem;

    .settingsValues {
        color: var(--accent);
    }
}

/* Dual-thumb range slider */
.rangeSlider {
    position: relative;
    height: 20px;

    /* Shared vertical centering for all children */
    .rangeTrack, .rangeFill, input[type="range"] {
        position: absolute;
        top: 50%;
        transform: translateY(-50%);
        left: 0;
        height: 4px;
        border-radius: 2px;
    }

    .rangeTrack {
        width: 100%;
        background: var(--border);
    }

    .rangeFill {
        background: var(--accent);
        pointer-events: none;
    }

    input[type="range"] {
        width: 100%;
        -webkit-appearance: none;
        appearance: none;
        background: none;
        pointer-events: none;
        margin: 0;
        padding: 0;

        &::-webkit-slider-runnable-track {
            height: 4px;
            background: transparent;
        }

        &::-moz-range-track {
            height: 4px;
            background: transparent;
        }

        &::-webkit-slider-thumb {
            -webkit-appearance: none;
            height: 16px;
            width: 16px;
            border-radius: 50%;
            background: var(--accent);
            border: 2px solid var(--bg);
            pointer-events: auto;
            cursor: grab;
            margin-top: -6px; /* Center thumb on 4px track: -(16-4)/2 */
        }

        &::-moz-range-thumb {
            height: 16px;
            width: 16px;
            border-radius: 50%;
            background: var(--accent);
            border: 2px solid var(--bg);
            pointer-events: auto;
            cursor: grab;
        }
    }
}

.rangeBounds {
    display: flex;
    justify-content: space-between;
    font-family: var(--primaryFont);
    font-size: 0.55rem;
    color: var(--muted);
    margin-top: 0.3rem;
}

/* Toggle setting */
.toggleSetting {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-family: var(--primaryFont);
    font-size: 0.6rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: var(--muted);
    cursor: pointer;

    input {
        display: none;
    }

    .toggle {
        width: 36px;
        height: 20px;
        background: var(--border);
        border-radius: 10px;
        position: relative;
        transition: background 0.2s;
        flex-shrink: 0;

        &::after {
            content: "";
            position: absolute;
            top: 2px;
            left: 2px;
            width: 16px;
            height: 16px;
            background: var(--muted);
            border-radius: 50%;
            transition: all 0.2s;
        }
    }

    input:checked + .toggle {
        background: var(--accent);

        &::after {
            left: 18px;
            background: var(--bg);
        }
    }
}

#applyFilters {
    border-color: var(--accent);
    color: var(--accent);
    white-space: nowrap;
    margin-left: auto;

    &:hover {
        background: var(--accent);
        color: var(--bg);
    }
}

/* Stats bar */
#statsBar {
    display: flex;
    gap: 2rem;
    padding: 1rem 1rem;
    width: 100%;
    align-items: center;
    font-family: var(--primaryFont);
    font-size: 0.75rem;
    color: var(--muted);
    border-bottom: 1px solid var(--border);
    flex-wrap: wrap;
    text-transform: uppercase;

    .stat {
        display: flex;
        flex-direction: column;
        gap: 0.15rem;

        label {
            font-size: 0.6rem;
            letter-spacing: 0.12em;
        }

        p {
            font-size: 1rem;
            color: var(--text);
            font-weight: 500;
        }
    }

    #progressContainer {
        flex: 1;

        #progressBar {
            min-width: 120px;
            height: 3px;
            background: var(--border);
            border-radius: 2px;
            margin-top: 0.4rem;

            #progressFill {
                height: 100%;
                background: var(--accent);
                border-radius: 2px;
                transition: width 0.4s ease;
            }
        }
    }
}

/* Main arena */
#arena {
    flex: 1;
    width: 100%;
    max-width: 700px;
    padding: 3rem 1.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2rem;
}

/* Flashcard */
#card {
    animation: slideUp 0.35s ease;
    position: relative;
    width: 100%;
    padding-top: 62%;
    transform-style: preserve-3d;
    transition: transform 0.6s cubic-bezier(0.23, 1, 0.32, 1);
    transform: perspective(1200px); /* 3D flip effect. A transform so the script easily override it */

    &.flipped {
        transform: perspective(1200px) rotateY(180deg);
    }
}

/* Animate card entering the page */
@keyframes slideUp {
    from {
        opacity: 0;
        translate: 0 20px;
    }
}

.cardFace {
    position: absolute;
    inset: 0;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 12px;
    outline: 1px solid transparent; /* Smoothes out edges when card moving */
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    backface-visibility: hidden;
    overflow: hidden;
    padding: 1rem 1.2rem;

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

    .cardInfo {
        width: 100%;
        display: flex;
        justify-content: space-between;
        font-family: var(--primaryFont);
        font-size: 0.6rem;
        text-transform: uppercase;
        letter-spacing: 0.15em;
        color: var(--muted);
    }
}

/* Prevent dragging of images */
img {pointer-events: none}

.cardFace img {
    max-height: 55%;
    max-width: 80%;
    border-radius: 4px;
    filter: drop-shadow(0 8px 20px rgba(0, 0, 0, 0.5));
}

.cardFace h1 {
    font-family: var(--titleFont);
    font-weight: bold;
    text-align: center;
}

/* Location mode */
#minimapSlot, #locationMinimap {
    flex: 1;
    min-height: 0;
    width: 100%;
    border-radius: 6px;
    border: 1px solid var(--border);
    overflow: hidden;
    cursor: pointer;
    pointer-events: none;
    background: var(--card);
}

/* Leaflet zoom overrides */
.leaflet-zoom-animated {transform-origin: 0 0}
.leaflet-zoom-anim .leaflet-zoom-animated {transition: transform 0.25s cubic-bezier(0, 0, 0.25, 1)}

.leaflet-bottom {position: absolute; bottom: 0}
.leaflet-right {right: 10px}

.leaflet-control-zoom a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: 6px;
    border: 1px solid var(--border);
    background: rgba(0, 0, 0, 0.5);
    color: var(--accent);
    font-size: 16px;
    line-height: 1;
    text-decoration: none;
    cursor: pointer;
    pointer-events: auto;
    user-select: none;
    -webkit-user-drag: none;
    margin-bottom: 5px;

    &:hover {
        background: rgba(0, 0, 0, 0.75);
        border-color: var(--accent);
        transition: background 0.15s, border-color 0.15s;
    }
}

.cardFace.front {
    img {
        object-fit: contain;
    }

    h1 {
        font-size: clamp(1.6rem, 5vw, 3rem);
        padding: 1rem 2rem;
        line-height: 1.2;
    }
}

.cardFace.back .cardBackContent {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    flex: 1;
    min-height: 0;
    width: 100%;

    img {
        min-height: 0;
    }

    h1 {
        margin-top: 0.25rem;
        font-size: clamp(1.2rem, 4vw, 2rem);
    }

    p {
        font-family: var(--primaryFont);
        font-size: 0.7rem;
        color: var(--muted);
        text-align: center;
    }
}
/* Swipe overlays */
.skipOverlay    {border-color: var(--accent)}
.correctOverlay {border-color: var(--success)}
.wrongOverlay   {border-color: var(--error)}

.skipOverlay::after,
.correctOverlay::after,
.wrongOverlay::after {
    content: "";
    position: absolute;
    inset: 0;
    opacity: 0.25;
}
.skipOverlay::after    {background: linear-gradient(135deg, var(--accent),  var(--card))}
.correctOverlay::after {background: linear-gradient(135deg, var(--success), var(--card))}
.wrongOverlay::after   {background: linear-gradient(135deg, var(--error),   var(--card))}

/* Keyboard hints */
#keyboardHints {
    display: grid;
    width: 100%;
    grid-template-columns: 1fr auto 1fr;
    font-family: var(--primaryFont);
    font-size: 0.6rem;
    color: var(--muted);
    letter-spacing: 0.08em;

    span:last-child {direction: rtl} /* Keeps the arrow on the edge of the card */

    span::first-letter {
        padding: 0.1rem 0.35rem;
        margin: 0 1ch;
        border: 1px solid var(--border);
        border-radius: 3px;
        color: var(--muted);
    }
}

/* Action buttons */
#actionBar {
    display: flex;
    gap: 1rem;
    width: 100%;
    justify-content: center;

    button {
        font-family: var(--primaryFont);
        font-size: 0.75rem;
        background: transparent;
        letter-spacing: 0.1em;
        text-transform: uppercase;
        padding: 0.85rem 2rem;
        border-radius: 4px;
        border: 1px solid;
        cursor: pointer;
        transition: all 0.15s;
        flex: 1;
    }

    #flip {
        border-color: var(--border);
        color: var(--text);
        max-width: 220px;

        &:hover {
            border-color: var(--accent);
            color: var(--accent);
        }
    }

    #correct, #wrong {
        max-width: 180px;

        &:hover {color: var(--text)}
    }

    #correct {
        border-color: var(--success);
        color: var(--success);

        &:hover {background: var(--success)}
    }

    #wrong {
        border-color: var(--error);
        color: var(--error);

        &:hover {background: var(--error)}
    }

    #restart {
        border-color: var(--accent);
        color: var(--accent);
        max-width: 220px;

        &:hover {
            background: var(--accent);
            color: var(--bg);
        }
    }
}

/* Done screen */
#done {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
    padding: 2rem;

    .label {
        font-family: var(--primaryFont);
        font-size: 0.75rem;
        text-transform: uppercase;
        letter-spacing: 0.15em;
        color: var(--muted);
    }

    #score {
        font-family: var(--titleFont);
        font-size: 5rem;
        font-weight: 900;
        line-height: 1;
        color: var(--accent);
    }

    #message {
        font-size: 1.1rem;
        color: var(--muted);
        max-width: 300px;
    }
}

.toast {
    width: 100%;
    border: 1px solid var(--accent);
    color: var(--accent);
    font-family: var(--primaryFont);
    font-size: 0.72rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    text-align: center;
    border-radius: 4px;
    max-width: 180px;
    padding: 12px 0;
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    pointer-events: none;
    animation: slideToastUp 0.5s ease-out, hideToast 1.25s forwards 1s;
    background: var(--card);
}

@keyframes slideToastUp {from {translate: 0 15px}}
@keyframes hideToast {to {opacity: 0}}

/* Status messages */
#loadingMessage, #errorMessage {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    padding: 4rem;
    font-family: var(--primaryFont);
    font-size: 0.8rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

#loadingMessage {
    color: var(--muted);

    /* Loading spinner */
    &::before {
        content: "";
        width: 32px; height: 32px;
        border: 2px solid var(--border);
        border-top-color: var(--accent);
        border-radius: 50%;
        animation: spin 1s linear infinite;
    }
}

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

#errorMessage {color: var(--error)}