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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #0a1929 0%, #1a2332 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    color: #fff;
}

.container {
    max-width: 500px;
    width: 100%;
}

.header {
    text-align: center;
    margin-bottom: 30px;
}

.header h1 {
    font-size: 2rem;
    margin-bottom: 10px;
    background: linear-gradient(90deg, #00d4aa, #00ffc8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.header p {
    color: #8b9db8;
    font-size: 0.95rem;
}

.calculator-card {
    background: rgba(15, 30, 45, 0.8);
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
    border: 1px solid rgba(0, 212, 170, 0.2);
}

.direction-selector {
    display: flex;
    gap: 10px;
    margin-bottom: 25px;
}

.direction-btn {
    flex: 1;
    padding: 12px;
    background: rgba(30, 45, 60, 0.6);
    border: 2px solid rgba(0, 212, 170, 0.3);
    border-radius: 12px;
    color: #8b9db8;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.direction-btn:hover {
    border-color: rgba(0, 212, 170, 0.6);
    background: rgba(30, 45, 60, 0.9);
}

.direction-btn.active {
    background: linear-gradient(135deg, #00d4aa, #00b894);
    border-color: #00d4aa;
    color: #fff;
}

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

.input-label {
    display: block;
    color: #8b9db8;
    font-size: 0.9rem;
    margin-bottom: 8px;
    font-weight: 500;
}

.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
    background: rgba(20, 35, 50, 0.8);
    border: 2px solid rgba(0, 212, 170, 0.2);
    border-radius: 12px;
    padding: 15px;
    transition: border-color 0.3s ease;
}

.input-wrapper:focus-within {
    border-color: rgba(0, 212, 170, 0.6);
}

.input-wrapper input {
    flex: 1;
    background: transparent;
    border: none;
    color: #fff;
    font-size: 1.2rem;
    font-weight: 600;
    outline: none;
}

.input-wrapper input::placeholder {
    color: rgba(139, 157, 184, 0.5);
}

.currency-badge {
    background: rgba(0, 212, 170, 0.15);
    color: #00d4aa;
    padding: 6px 12px;
    border-radius: 8px;
    font-size: 0.9rem;
    font-weight: 700;
    margin-left: 10px;
}

.exchange-icon {
    text-align: center;
    margin: 15px 0;
    font-size: 1.5rem;
    color: #00d4aa;
}

@media (max-width: 600px) {
    .header h1 {
        font-size: 1.5rem;
    }

    .calculator-card {
        padding: 20px;
    }

    .direction-btn {
        font-size: 0.85rem;
        padding: 10px;
    }

    .input-wrapper input {
        font-size: 1rem;
    }
}