* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI",
                 Roboto, Oxygen, Ubuntu, Cantarell, "Helvetica Neue", Arial, sans-serif;
    background: #f5f5f5;
    color: #3f4350;
    display: flex;
    min-height: 100vh;
}

.left-panel {
    flex: 1;
    background: #0058cc;
    color: white;
    padding: 60px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.right-panel {
    flex: 1;
    background: #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
}

.login-box {
    width: 100%;
    max-width: 360px;
}

.logo {
    font-size: 28px;
    font-weight: 700;
    color: #0058cc;
    text-align: center;
    margin-bottom: 30px;
}

h2 {
    text-align: center;
    margin-bottom: 20px;
}

label {
    display: block;
    font-size: 14px;
    margin-top: 15px;
    margin-bottom: 6px;
}

input {
    width: 100%;
    padding: 10px 12px;
    font-size: 15px;
    border: 1px solid #d1d5db;
    border-radius: 4px;
}

input.error-input {
    border-color: #b42318;
}

input:focus {
    outline: none;
    border-color: #0058cc;
}

.error {
    display: none;
    background: #fdecea;
    border: 1px solid #f5c2c0;
    color: #b42318;
    padding: 10px 12px;
    border-radius: 4px;
    font-size: 14px;
    margin-bottom: 15px;
}

button {
    width: 100%;
    margin-top: 25px;
    padding: 12px;
    background: #0058cc;
    color: white;
    border: none;
    border-radius: 4px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
}

button:hover {
    background: #0047a3;
}

.footer {
    margin-top: 40px;
    font-size: 12px;
    color: #888;
    text-align: center;
}

@media (max-width: 900px) {
    body {
        flex-direction: column;
    }

    .left-panel {
        display: none;
    }
}