* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

h1 {
    text-align: center;
    color: white;
    font-size: 2.5rem;
    margin-bottom: 30px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.controls {
    display: flex;
    gap: 10px;
    justify-content: center;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.2);
}

.btn-add {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-add:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.3);
}

.btn-reset {
    background: #ff6b6b;
    color: white;
}

.btn-reset:hover {
    background: #ff5252;
    transform: translateY(-2px);
}

.btn-cancel {
    background: #95a5a6;
    color: white;
}

.btn-cancel:hover {
    background: #7f8c8d;
}

.timezone-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.timezone-modal.active {
    display: flex;
}

.modal-content {
    background: white;
    border-radius: 12px;
    padding: 30px;
    max-width: 400px;
    width: 90%;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
}

.modal-content h2 {
    margin-bottom: 20px;
    color: #333;
}

#timezone-search {
    width: 100%;
    padding: 10px;
    margin-bottom: 15px;
    border: 2px solid #667eea;
    border-radius: 6px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

#timezone-search:focus {
    outline: none;
    border-color: #764ba2;
}

.timezone-list {
    max-height: 300px;
    overflow-y: auto;
    margin-bottom: 20px;
    border: 1px solid #ecf0f1;
    border-radius: 6px;
}

.timezone-item {
    padding: 10px;
    cursor: pointer;
    transition: background 0.2s;
    border-bottom: 1px solid #ecf0f1;
}

.timezone-item:hover {
    background: #f0f7ff;
}

.timezone-item:last-child {
    border-bottom: none;
}

.clocks-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.clock {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
    position: relative;
}

.clock:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.25);
}

.clock-timezone {
    font-size: 0.85rem;
    color: #7f8c8d;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 10px;
}

.clock-time {
    font-size: 2.5rem;
    font-weight: bold;
    color: #667eea;
    font-family: 'Courier New', monospace;
    letter-spacing: 2px;
    margin-bottom: 10px;
}

.clock-date {
    font-size: 0.9rem;
    color: #95a5a6;
    margin-bottom: 15px;
}

.clock-offset {
    font-size: 0.8rem;
    background: #ecf0f1;
    padding: 6px 12px;
    border-radius: 20px;
    display: inline-block;
    color: #555;
    margin-bottom: 15px;
}

.clock-remove {
    position: absolute;
    top: 10px;
    right: 10px;
    background: #ff6b6b;
    color: white;
    border: none;
    border-radius: 50%;
    width: 30px;
    height: 30px;
    cursor: pointer;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.3s, transform 0.3s;
}

.clock-remove:hover {
    background: #ff5252;
    transform: scale(1.1);
}

.empty-state {
    grid-column: 1 / -1;
    text-align: center;
    padding: 60px 20px;
    color: white;
}

.empty-state p {
    font-size: 1.2rem;
    margin-bottom: 20px;
}

@media (max-width: 768px) {
    h1 {
        font-size: 1.8rem;
    }

    .clocks-container {
        grid-template-columns: 1fr;
    }

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

    .modal-content {
        padding: 20px;
    }
}