:root {
    --primary-blue: #4A90E2;
    --highlight-orange: #F39C12;
    --soft-cream: #FFF9E5;
    --dark-gray: #34495E;
    --success-green: #2ECC71;
    --error-red: #E74C3C;
    --light-gray: #ECF0F1;
    --button-height: 50px;
    --road-height: 30px;
    --gap: 10px;
}

body {
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--soft-cream);
    color: var(--dark-gray);
}

.game-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

.game-area {
    display: grid;
    grid-template-columns: 50px 1fr 50px;
    gap: var(--gap);
    min-width: 600px;
    border: 2px solid var(--dark-gray);
    border-radius: 8px;
    padding: var(--gap);
    background-color: var(--light-gray);
}

.button-column {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    width: 50px;
    height: 170px;
}

.pipe {
    height: 50px;
    width: 50px;
    background-color: var(--primary-blue);
    border-radius: 4px;
    cursor: pointer;
    position: relative;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    box-sizing: border-box;
}

.square {
    width: 40px;
    height: 20px;
    background-color: var(--highlight-orange);
    position: absolute;
    left: 5px;
    transition: top 0.3s ease-out;
}

.square.top {
    top: 5px;
}

.square.bottom {
    top: 25px;
}

.road-container {
    display: flex;
    flex-direction: column;
    gap: var(--gap);
}

.road-pair {
    height: var(--button-height);
    display: flex;
    flex-direction: column;
    justify-content: space-evenly;
}

.road {
    height: 15px;
    background-color: var(--primary-blue);
    border-radius: 4px;
    position: relative;
    overflow: visible;
}

.obstacle {
    position: absolute;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    top: -2.5px;
    left: calc(50% - 10px);
    will-change: transform;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    line-height: 1;
}

.collision {
    animation: flash 0.3s;
    animation-fill-mode: both;
}

@keyframes flash {
    0%, 100% { 
        opacity: 1;
        transform: scale(1.2);
    }
    50% { 
        opacity: 0.3;
        transform: scale(1);
    }
}

.controls {
    margin-top: var(--gap);
    display: flex;
    justify-content: flex-end;
    align-items: center;
    gap: 20px;
    flex-wrap: wrap;
}

.score-container {
    flex-grow: 1;
    text-align: left;
}

button {
    padding: 10px 20px;
    font-size: 1.2em;
    background-color: var(--primary-blue);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.2s;
    order: 2;
}

button:hover {
    background-color: var(--highlight-orange);
}

.score, .timer {
    font-size: 1.5em;
    margin-top: var(--gap);
}

.timer {
    color: var(--dark-gray);
}

.collection {
    width: 100%;
    margin-top: 10px;
    padding: 10px;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    font-size: 16px;
    line-height: 1.5;
    word-wrap: break-word;
    order: 3;
}

.collection:empty {
    display: none;