* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial, sans-serif;
}

body {
    background-color: #f5f5f5;
    color: #333;
    padding: 20px;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    background-color: white;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

.tab-navigation {
    display: flex;
    background-color: #3498db;
}

.tab-button {
    padding: 15px 20px;
    background: none;
    border: none;
    color: white;
    font-size: 16px;
    cursor: pointer;
    transition: background-color 0.3s;
    flex-grow: 1;
    text-align: center;
}

.tab-button:hover {
    background-color: #2980b9;
}

.tab-button.active {
    background-color: #2c3e50;
}

.tab-content {
    padding: 20px;
    display: none;
}

.tab-content.active {
    display: block;
}

.time-display {
    font-size: 3rem;
    text-align: center;
    margin: 20px 0;
    font-family: 'Courier New', monospace;
    color: #2c3e50;
}

button {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 10px 15px;
    border-radius: 5px;
    cursor: pointer;
    margin: 5px;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #2980b9;
}

input, select {
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    margin: 5px;
}

.controls {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 20px;
}

.status {
    text-align: center;
    font-style: italic;
    color: #7f8c8d;
}

.clock-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.clock {
    background-color: #f9f9f9;
    padding: 15px;
    border-radius: 8px;
    box-shadow: 0 1px 5px rgba(0, 0, 0, 0.1);
    text-align: center;
    position: relative;
}

.clock h3 {
    margin-bottom: 10px;
    color: #3498db;
}

.clock .time-display {
    font-size: 2rem;
}

h2 {
    text-align: center;
    margin-bottom: 20px;
    color: #2c3e50;
}

.add-clock-container {
    display: flex;
    justify-content: center;
    margin: 20px 0;
    flex-wrap: wrap;
}

.remove-clock {
    position: absolute;
    top: 5px;
    right: 5px;
    background-color: #e74c3c;
    color: white;
    border: none;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    font-size: 12px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
}

.remove-clock:hover {
    background-color: #c0392b;
}

select {
    min-width: 250px;
}