/* Payments learning note (v1)
 * Shared stylesheet. CSS controls appearance, not database behaviour. :root variables hold reusable colours; selectors choose elements; declarations set their visual properties. Media queries adapt layout to screen width.
 */
:root {
    --brand: #005F61;
    --brand-dark: #0D5257;
    --brand-soft: #e6f2f2;

    --text: #253435;
    --muted: #607172;
    --background: #f4f7f7;
    --border: #dce5e5;

    --sanctuary-teal: #005F61;
    --dark-green: #0D5257;
    --dark-blue: #00617F;
    --turquoise: #00C7B1;
    --green: #009A44;
    --dark-purple: #470A68;
    --red: #E1523E;
    --teal: #008C95;
    --blue: #307FE2;
    --light-blue: #2AD2C9;
    --bright-green: #C4D600;
    --mid-purple: #8031A7;
    --orange: #FF7F41;

    --success: var(--green);
    --warning: var(--orange);
    --danger: var(--red);
    --info: var(--dark-blue);
    --purple: var(--dark-purple);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    color: var(--text);
    background: var(--background);
    font: 16px/1.6 system-ui, sans-serif;
}

a {
    color: var(--brand);
}

a:focus-visible {
    outline: 3px solid var(--brand);
    outline-offset: 4px;
}

.skip-link {
    position: absolute;
    top: -100px;
    left: 16px;
    padding: 12px;
    background: white;
    z-index: 10;
}

.skip-link:focus {
    top: 12px;
}

.app-header {
    min-height: 84px;
    padding: 18px 32px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    background: white;
    border-bottom: 4px solid var(--brand);
}

.brand {
    color: var(--brand);
    font-size: 21px;
    font-weight: 750;
    text-decoration: none;
}

.demo-label {
    color: var(--muted);
    font-size: 13px;
}

.app-shell {
    display: grid;
    grid-template-columns: 240px minmax(0, 1fr);
    min-height: calc(100vh - 88px);
}

.sidebar {
    padding: 28px 16px;
    background: white;
    border-right: 1px solid var(--border);
}

.nav-heading {
    margin: 0 12px 12px;
    color: var(--muted);
    font-size: 12px;
    letter-spacing: .1em;
    text-transform: uppercase;
}

.nav-link {
    display: block;
    padding: 12px 16px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: background-color .15s ease, color .15s ease;
}

.nav-link:hover {
    background: var(--background);
    color: var(--brand-dark);
}

.nav-link[aria-current="page"] {
    background: var(--brand-soft);
    color: var(--brand-dark);
}

main {
    min-width: 0;
    padding: 36px;
}

.eyebrow {
    margin: 0;
    color: var(--brand);
    font-size: 13px;
    font-weight: 700;
    letter-spacing: .08em;
    text-transform: uppercase;
}

h1 {
    margin: 6px 0 8px;
    font-size: clamp(28px, 3vw, 38px);
    line-height: 1.2;
}

.introduction {
    margin: 0 0 28px;
    color: var(--muted);
}

.card {
    padding: 28px;
    background: white;
    border: 1px solid var(--border);
    border-radius: 10px;
}

.card h2 {
    margin-top: 0;
    font-size: 20px;
}

.card p {
    max-width: 75ch;
}

.build-status {
    display: inline-block;
    padding: 5px 12px;
    background: var(--brand-soft);
    color: var(--brand-dark);
    border-radius: 20px;
    font-size: 13px;
    font-weight: 650;
}

@media (min-width: 1800px) {
    main {
        padding: 44px 56px;
    }
}

@media (max-width: 760px) {
    .app-header {
        padding: 16px 20px;
        flex-wrap: wrap;
    }

    .app-shell {
        grid-template-columns: 1fr;
    }

    .sidebar {
        padding: 12px 20px;
        border-right: 0;
        border-bottom: 1px solid var(--border);
    }

    .nav-heading {
        display: none;
    }

    main {
        padding: 24px 20px;
    }
}

@media (prefers-reduced-motion: reduce) {
    .nav-link {
        transition: none;
    }
}

/* Payment request form */
.form-notice {
    margin-bottom: 24px;
    padding: 16px 20px;
    border-left: 4px solid var(--brand);
    background: var(--brand-soft);
    color: var(--brand-dark);
}

.form-notice strong {
    display: block;
}

.payment-form {
    display: grid;
    gap: 24px;
}

.payment-form .card h2 {
    margin-bottom: 8px;
}

.section-description {
    margin-top: 0;
    color: var(--muted);
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px 28px;
    margin-top: 20px;
}

.field {
    display: flex;
    flex-direction: column;
    gap: 7px;
    min-width: 0;
}

.field-wide {
    grid-column: 1 / -1;
}

.field label {
    font-size: 14px;
    font-weight: 650;
}

.field input,
.field select,
.field textarea {
    width: 100%;
    padding: 11px 12px;
    border: 1px solid #a7b7b8;
    border-radius: 6px;
    background: white;
    color: var(--text);
    font: inherit;
}

.field textarea {
    resize: vertical;
}

.field input:focus-visible,
.field select:focus-visible,
.field textarea:focus-visible {
    outline: 3px solid var(--brand);
    outline-offset: 2px;
}

.field small {
    color: var(--muted);
    font-size: 13px;
}

.form-actions {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 16px;
}

.button-primary,
.button-secondary {
    display: inline-block;
    padding: 11px 20px;
    border: 1px solid var(--brand);
    border-radius: 6px;
    font: inherit;
    font-weight: 650;
    text-align: center;
    text-decoration: none;
}

.button-primary {
    background: var(--brand);
    color: white;
}

.button-primary:disabled {
    background: #e3e9e9;
    border-color: #cbd5d5;
    color: #526363;
    cursor: not-allowed;
}

.button-secondary {
    background: white;
    color: var(--brand);
}

.button-secondary:hover {
    background: var(--brand-soft);
}

@media (max-width: 760px) {
    .form-grid {
        grid-template-columns: 1fr;
    }
}