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

body {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: linear-gradient(135deg, #f1f1f1, #e6e6e6);
}

.container {
    text-align: center;
    background: #ffffff;
    padding: 40px;
    border-radius: 15px;
    box-shadow: 0 15px 25px rgba(0, 0, 0, 0.15);
    max-width: 400px;
    width: 100%;
    animation: fadeIn 0.6s ease-out;
}

@keyframes fadeIn {
    0% { opacity: 0; transform: translateY(20px); }
    100% { opacity: 1; transform: translateY(0); }
}

h1 {
    font-size: 28px;
    color: #2c3e50;
    margin-bottom: 30px;
}

.timer {
    font-size: 60px;
    color: #e74c3c;
    font-weight: bold;
    letter-spacing: 2px;
    margin: 20px 0;
    background: #f1f1f1;
    padding: 20px;
    border-radius: 10px;
    box-shadow: inset 0 4px 8px rgba(0, 0, 0, 0.1);
}

.controls {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-top: 25px;
    margin-bottom: 35px;
}

button {
    padding: 12px 24px;
    font-size: 16px;
    font-weight: 600;
    color: #ffffff;
    background: linear-gradient(135deg, #3498db, #2980b9);
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 5px 10px rgba(52, 152, 219, 0.3);
}

button:hover {
    background: linear-gradient(135deg, #3a99d9, #3498db);
    box-shadow: 0 8px 15px rgba(52, 152, 219, 0.4);
}

button:disabled {
    background: #bdc3c7;
    cursor: not-allowed;
    box-shadow: none;
}

.settings {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

label {
    font-size: 14px;
    color: #34495e;
}

input[type="number"] {
    padding: 8px;
    width: 70px;
    font-size: 16px;
    text-align: center;
    border: 2px solid #ecf0f1;
    border-radius: 6px;
    background: #ffffff;
    color: #34495e;
    transition: border 0.3s ease;
}

input[type="number"]:focus {
    border: 2px solid #3498db;
    outline: none;
}