:root {
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-sum: #10b981;
    --accent-sub: #f43f5e;
    --accent-mult: #3b82f6;
    --accent-div: #f59e0b;
    --input-bg: #334155;
    --input-focus: #64748b;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    background-color: var(--card-bg);
    padding: 2.5rem;
    border-radius: 24px;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    width: 100%;
    max-width: 500px;
    animation: fadeIn 0.5s ease-out;
}

header {
    text-align: center;
    margin-bottom: 2rem;
}

header h1 {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, #60a5fa, #c084fc);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.input-group {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.input-wrapper {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

label {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
}

input {
    background-color: var(--input-bg);
    border: 2px solid transparent;
    border-radius: 12px;
    padding: 1rem;
    font-size: 1.25rem;
    color: white;
    outline: none;
    transition: all 0.3s ease;
    width: 100%;
}

input:focus {
    border-color: #60a5fa;
    background-color: var(--input-focus);
    box-shadow: 0 0 15px rgba(96, 165, 250, 0.2);
}

.results-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.result-card {
    background-color: rgba(255, 255, 255, 0.03);
    border-radius: 16px;
    padding: 1.25rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    transition: transform 0.2s;
    border: 1px solid rgba(255, 255, 255, 0.05);
}

.result-card:hover {
    transform: translateY(-5px);
    background-color: rgba(255, 255, 255, 0.06);
}

.result-card.sum {
    border-bottom: 3px solid var(--accent-sum);
}

.result-card.sub {
    border-bottom: 3px solid var(--accent-sub);
}

.result-card.mult {
    border-bottom: 3px solid var(--accent-mult);
}

.result-card.div {
    border-bottom: 3px solid var(--accent-div);
}

.icon {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    opacity: 0.8;
}

.sum .icon {
    color: var(--accent-sum);
}

.sub .icon {
    color: var(--accent-sub);
}

.mult .icon {
    color: var(--accent-mult);
}

.div .icon {
    color: var(--accent-div);
}

.result-card h3 {
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

.result-card span {
    font-size: 1.5rem;
    font-weight: 600;
    word-break: break-all;
    text-align: center;
    line-height: 1.2;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 480px) {
    .input-group {
        grid-template-columns: 1fr;
    }

    .results-grid {
        grid-template-columns: 1fr;
    }
}

.timestamp {
    text-align: center;
    margin-top: 1.5rem;
    color: var(--text-secondary);
    font-size: 0.8rem;
    font-style: italic;
    opacity: 0.7;
}