* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background: radial-gradient(circle, rgba(80, 0, 0, 1) 5%, rgba(20, 0, 0, 1) 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.toggle {
    position: relative;
    display: inline-block;
    width: 60px;
    height: 34px;
}

.toggle input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #444;
    transition: .4s;
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: .4s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: #ff4444;
}

input:checked + .slider:before {
    transform: translateX(26px);
}

.calculator {
    background-color: rgba(30, 30, 30, 0.95);
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    width: 100%;
    max-width: 550px;
    padding: 30px;
    position: relative;
    overflow: hidden;
    border: 1px solid #444;
}

.calculator::before {
    content: '';
    background: #ff4444;
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 5px;
}

.header {
    text-align: center;
    margin-bottom: 25px;
}

.header h1 {
    color: #ff4444;
    font-size: 2.2rem;
    margin-bottom: 5px;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.3);
}

.header p {
    color: #ccc;
    font-size: 1rem;
}

.input-group {
    margin-bottom: 20px;
}

.input-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #ff4444;
    text-align: center;
}

.input-group input {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #555;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s;
    text-align: center;
    background-color: #333;
    color: white;
}

.input-group input:focus {
    border-color: #ff4444;
    outline: none;
    box-shadow: 0 0 5px rgba(255, 68, 68, 0.5);
}

.currency-input {
    display: flex;
    gap: 10px;
}

.currency-input input {
    flex: 2;
}

.custom-select {
    position: relative;
    flex: 1;
    user-select: none;
}

.custom-select .selected {
    padding: 12px 15px;
    border: 2px solid #555;
    border-radius: 8px;
    background: #333;
    cursor: pointer;
    font-size: 1rem;
    text-align: center;
    transition: border-color 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    color: white;
}

.custom-select .selected:hover {
    border-color: #ff4444;
}

.custom-select.open .selected {
    border-color: #ff4444;
    box-shadow: 0 0 5px rgba(255, 68, 68, 0.5);
}

.custom-select .arrow {
    width: 8px;
    height: 8px;
    border-left: 2px solid #ff4444;
    border-bottom: 2px solid #ff4444;
    transform: rotate(-45deg);
    transition: transform 0.2s ease, border-color 0.2s ease;
}

.custom-select.open .arrow {
    transform: rotate(135deg);
    border-color: #ff4444;
}

.custom-select .options {
    position: absolute;
    top: calc(100% + 5px);
    left: 0;
    width: 100%;
    background: #333;
    border: 2px solid #ff4444;
    border-radius: 8px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.3);
    display: none;
    z-index: 10;
    overflow: hidden;
}

.custom-select.open .options {
    display: block;
    animation: fadeIn 0.15s ease-in-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-5px); }
    to { opacity: 1; transform: translateY(0); }
}

.custom-select .options div {
    padding: 10px 15px;
    cursor: pointer;
    transition: background 0.2s, color 0.2s;
    text-align: center;
    color: white;
}

.custom-select .options div:hover {
    background: #ff4444;
    color: white;
}

.calculate-btn {
    background: #ff4444;
    color: white;
    border: none;
    border-radius: 8px;
    padding: 14px;
    width: 100%;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    margin-top: 10px;
}

.calculate-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(255, 68, 68, 0.4);
}

.calculate-btn:active {
    transform: translateY(0);
}

.results {
    margin-top: 30px;
    background-color: #2a2a2a;
    border-radius: 10px;
    padding: 20px;
    box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.2);
    display: none;
    border: 1px solid #444;
}

.results h2 {
    color: #ff4444;
    margin-bottom: 15px;
    text-align: center;
    font-size: 1.4rem;
}

.result-item {
    display: flex;
    justify-content: space-between;
    padding: 10px 0;
    border-bottom: 1px solid #444;
}

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

.result-label {
    font-weight: 600;
    color: #ccc;
    text-align: center;
}

.result-value {
    font-weight: 700;
    color: #ff4444;
    text-align: center;
}

.footer {
    margin-top: 25px;
    text-align: center;
    color: #ff4444;
    font-style: italic;
    padding-top: 15px;
    border-top: 1px solid #444;
    font-size: 20px;
}

.footer2 {
    margin-top: 10px;
    text-align: center;
    color: #aaa;
    font-style: italic;
    padding-top: 15px;
    border-top: 1px solid #444;
    font-size: 10px;
}

@media (max-width: 480px) {
    .calculator {
        padding: 20px;
    }

    .header h1 {
        font-size: 1.8rem;
    }

    .currency-input {
        flex-direction: column;
        text-align: center;
    }
}