.tool-container {
    background: #fff;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    border: 1px solid #eee;
}

.result-area {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
}

#pw-result {
    flex-grow: 1;
    padding: 15px;
    font-size: 1.5rem;
    font-family: 'Courier New', Courier, monospace;
    border: 2px solid #333f47;
    border-radius: 4px;
    background: #f9f9f9;
    text-align: center;
}

.btn-copy {
    padding: 0 20px;
    background: #55acee;
    color: #fff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-weight: bold;
}

.setting-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 30px;
    padding: 20px;
    background: #f4f4f4;
    border-radius: 6px;
}

.setting-item label {
    display: block;
    font-weight: bold;
    margin-bottom: 10px;
    color: #555;
}

#pw-length {
    width: 100%;
    cursor: pointer;
}

.checkbox-group label {
    display: block;
    font-weight: normal;
    cursor: pointer;
    margin-bottom: 8px;
}

.btn-main {
    width: 100%;
    padding: 15px;
    font-size: 1.1rem;
    background: #333f47;
    color: #fff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-weight: bold;
}

.btn-main:hover { opacity: 0.9; }

@media (max-width: 600px) {
    .setting-grid { grid-template-columns: 1fr; }
    #pw-result { font-size: 1.1rem; }
}