:root {
    --bg: #f3f4f6;
    --surface: #ffffff;
    --surface-subtle: #f8fafc;
    --border: #d7dce2;
    --border-strong: #b9c0c9;
    --text: #111827;
    --muted: #667085;
    --primary: #1f5ea8;
    --primary-dark: #174a86;
    --danger: #b42318;
    --success: #16794d;
    --shadow: 0 4px 18px rgba(17, 24, 39, .06);
}

* { box-sizing: border-box; }

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

body {
    font-family: "Segoe UI", Inter, ui-sans-serif, system-ui, sans-serif;
    background: var(--bg);
    color: var(--text);
    font-size: 14px;
}

a {
    color: var(--primary);
    text-decoration: none;
}

button,
input,
select,
textarea {
    font: inherit;
}

.site-header {
    min-height: 58px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
    background: #fff;
    border-bottom: 1px solid var(--border);
}

.brand {
    color: var(--text);
    font-weight: 650;
    letter-spacing: -.01em;
}

.button {
    border: 1px solid var(--border-strong);
    border-radius: 4px;
    padding: 8px 12px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    cursor: pointer;
    font-weight: 600;
    background: #fff;
    color: var(--text);
}

.button:hover {
    background: #f8fafc;
}

.button-primary {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
}

.button-primary:hover {
    background: var(--primary-dark);
    border-color: var(--primary-dark);
}

.button-ghost {
    background: #fff;
}

.button-large {
    padding: 10px 14px;
}

.login-shell {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 24px;
    background: #eef1f4;
}

.login-card {
    width: min(410px, 100%);
    background: #fff;
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    padding: 30px;
}

.login-brand {
    margin-bottom: 24px;
}

.login-brand h1 {
    margin: 0 0 5px;
    font-size: 22px;
    font-weight: 650;
}

.login-brand p {
    margin: 0;
    color: var(--muted);
}

.stack-form {
    display: grid;
    gap: 17px;
}

.stack-form label {
    display: grid;
    gap: 7px;
    font-weight: 600;
}

.stack-form input,
.stack-form select,
.stack-form textarea {
    width: 100%;
    padding: 9px 10px;
    border: 1px solid var(--border-strong);
    border-radius: 3px;
    background: #fff;
    color: var(--text);
    outline: none;
}

.stack-form input:focus,
.stack-form select:focus,
.stack-form textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(31, 94, 168, .12);
}

.stack-form small {
    font-weight: 400;
    color: var(--muted);
}

.alert {
    border-left: 3px solid;
    padding: 10px 12px;
    margin-bottom: 18px;
}

.alert-error {
    background: #fff5f4;
    border-color: var(--danger);
    color: #8f1710;
}

.password-generator {
    display: flex;
    gap: 8px;
}

.password-generator input {
    flex: 1;
}

code {
    background: #eef1f4;
    border: 1px solid #e1e5ea;
    padding: 1px 4px;
    font-family: "Cascadia Mono", Consolas, monospace;
    font-size: .94em;
}