* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
body {
    background-color: #f0f2f5;
    font-family: sans-serif;
}
.app-container {
    max-width: 600px;
    margin: 50px auto;
    background-color: white;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    padding: 24px;
}
.info-panels {
    display: flex;
    justify-content: space-between;
    margin-bottom: 24px;
}
.panel {
    background-color: #f7f7f7;
    padding: 12px;
    border-radius: 8px;
    text-align: center;
    flex: 1;
    margin: 0 5px;
}
.panel-label {
    font-size: 10px;
    color: #888;
    font-weight: 700;
    text-transform: uppercase;
}
.panel-value {
    font-size: 24px;
    font-weight: 700;
    color: #333;
    margin-top: 4px;
}
#simulation-container {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 250px;
    border: 1px solid #eee;
}
#seesaw-container {
    position: relative;
    width: 400px;
    height: 100%;
}
#seesaw-plank {
    width: 400px;
    height: 20px;
    background-color: #8B4513;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    z-index: 5;
    transition: transform 0.5s ease-in-out;
}
#pivot {
    width: 0;
    height: 0;
    border-left: 15px solid transparent;
    border-right: 15px solid transparent;
    border-bottom: 40px solid #654321;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, 0);
    z-index: 4;
}
.weight {
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: bold;
    z-index: 6;
}
#weight-preview {
    position: fixed;
    display: none;
    background-color: rgba(52, 152, 219, 0.7);
    border-radius: 50%;
    color: white;
    font-weight: bold;
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: none;
    z-index: 1000;
}
#preview-line {
    position: fixed;
    display: none;
    width: 2px;
    background-image: linear-gradient(to bottom, #3498db 60%, transparent 40%);
    background-size: 100% 10px;
    pointer-events: none;
    z-index: 999;
    transform: translateX(-50%);
}
.falling-weight {
    position: fixed;
    z-index: 1001;
    transition: top 0.4s cubic-bezier(0.6, -0.28, 0.735, 0.045);
}
.controls-separator {
    height: 40px;
    background-color: #e0e0e0;
    margin: 20px -24px 0;
}
#reset-button {
    border: none;
    display: block;
    margin: 20px auto;
    background-color: #2c3e50;
    color: white;
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s;
}
#reset-button:hover {
    background-color: #34495e;
}
#log-container {
    margin-top: 20px;
    border-top: 1px solid #eee;
    padding-top: 20px;
    max-height: 150px;
    overflow-y: auto;
}
.log-item {
    padding: 8px;
    font-size: 14px;
    color: #555;
    border-bottom: 1px solid #f0f0f0;
}

#reset-button {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.log-item span {
    margin-right: 8px;
}