html, body {
    height: 100%;
    margin: 0;
}

body {
    font-family: Arial;
    color: white;
    display: flex;
    justify-content: center;
    background: linear-gradient(135deg, #3F567F, #412653);
}

.main-container {
    width: 95%;
    max-width: 1200px;
}

.header {
    background: #563457;
    padding: 20px;
    text-align: center;
}

.content {
    display: flex;
    gap: 20px;
    margin-top: 20px;
}

.sidebar {
    width: 250px;
    background: #3F567F;
    padding: 15px;
    border-radius: 10px;
}

.sidebar button {
    width: 100%;
    margin: 6px 0;
    padding: 10px;
    background: #E0563F;
    border: none;
    color: white;
    border-radius: 6px;
}

.main {
    flex: 1;
    background: #412653;
    padding: 15px;
    border-radius: 10px;
}

.output-box, .code-box {
    background: #1a1b3a;
    padding: 20px;
    margin-bottom: 15px;
}

.calc-row {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.calc-buttons, .todo-buttons {
    display: flex;
    gap: 8px;
}

input {
    padding: 8px;
    border-radius: 6px;
    border: none;
}

img {
    margin-top: 10px;
    border-radius: 10px;
}