body {
    font-family: system-ui, sans-serif;
    margin: 0;
    color: #222;
    background: #fafafa;
}
header {
    background: #1f2937;
    padding: 1rem 2rem;
}
nav a {
    color: white;
    margin-right: 1.5rem;
    text-decoration: none;
}
main {
    max-width: 1100px;
    margin: 2rem auto;
    padding: 0 1rem;
}
.card, .result, .answer {
    background: white;
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 1rem;
    margin: 1rem 0;
}
textarea, input[type=file] {
    width: 100%;
    box-sizing: border-box;
    margin: .5rem 0 1rem;
}
button {
    padding: .5rem .9rem;
    cursor: pointer;
}
button.danger {
    background: #b91c1c;
    color: white;
    border: 0;
}
table {
    width: 100%;
    border-collapse: collapse;
    background: white;
}
th, td {
    border: 1px solid #ddd;
    padding: .7rem;
    vertical-align: top;
    text-align: left;
}
.inline-form {
    margin-bottom: .6rem;
}
.message {
    padding: .8rem;
    background: #ecfdf5;
    border: 1px solid #a7f3d0;
}
pre {
    white-space: pre-wrap;
    background: #f5f5f5;
    padding: .8rem;
}
.answer-text {
    white-space: pre-wrap;
    line-height: 1.5;
}

nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}
.nav-links {
    display: flex;
    align-items: center;
}
.nav-user {
    display: flex;
    align-items: center;
    gap: 1rem;
    color: white;
}
.logout-form {
    display: inline;
    margin: 0;
}
.link-button {
    background: none;
    border: 0;
    color: white;
    padding: 0;
    text-decoration: underline;
    cursor: pointer;
    font: inherit;
}
.login-card {
    max-width: 420px;
    margin: 4rem auto;
    padding: 1.5rem;
    background: white;
    border: 1px solid #ddd;
    border-radius: 8px;
}
.login-card label:not(.remember-me) {
    display: block;
    margin-top: 1rem;
    font-weight: 600;
}
.login-card input[type=text],
.login-card input[type=password] {
    width: 100%;
    box-sizing: border-box;
    margin-top: .4rem;
    padding: .55rem;
}
.remember-me {
    display: flex;
    align-items: center;
    gap: .5rem;
    margin: 1rem 0;
}
.validation-error {
    color: #b91c1c;
    margin-top: .35rem;
}