:root {
    font-family:
        system-ui,
        -apple-system,
        'Segoe UI',
        sans-serif;
    color: #193c43;
    background: #f4f7f8;
    font-size: 15px;
}
* {
    box-sizing: border-box;
}
body {
    margin: 0;
}
a {
    color: #087c74;
    text-decoration: none;
}
a:hover {
    text-decoration: underline;
}
.top {
    height: 82px;
    padding: 0 max(24px, calc((100vw - 1100px) / 2));
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: white;
    border-bottom: 1px solid #e0e9e9;
}
.brand {
    font-size: 19px;
    font-weight: 750;
    display: flex;
    align-items: center;
    gap: 10px;
    white-space: nowrap;
}
.brand b {
    background: #103d40;
    color: #bcebd9;
    padding: 7px 12px;
    border-radius: 10px;
}
.brand span {
    font-weight: 400;
    color: #819596;
}
.top nav {
    display: flex;
    gap: 22px;
    font-size: 13px;
}
main {
    max-width: 1100px;
    margin: auto;
    padding: 36px 24px 45px;
}
h1 {
    font-size: 38px;
    line-height: 1.15;
    letter-spacing: -1.2px;
    margin: 12px 0 15px;
}
h2 {
    font-size: 20px;
    letter-spacing: -0.3px;
    margin: 0 0 18px;
}
h3 {
    font-size: 15px;
    margin: 24px 0 9px;
}
p,
li {
    color: #617b80;
    line-height: 1.8;
}
li {
    padding: 0 0 10px 6px;
}
.intro {
    font-size: 17px;
    max-width: 780px;
}
.eyebrow {
    font-size: 10px;
    letter-spacing: 1.7px;
    font-weight: 750;
    color: #628884;
    margin-top: 24px;
}
.back {
    font-size: 12px;
}
.flow {
    display: inline-block;
    background: #e3f1eb;
    color: #28776b;
    font:
        12px ui-monospace,
        monospace;
    border-radius: 7px;
    padding: 12px 15px;
    margin: 10px 0 24px;
}
.panel {
    background: #fff;
    border: 1px solid #e0e8ea;
    border-radius: 12px;
    padding: 28px;
    margin-bottom: 22px;
    min-width: 0;
}
.help-grid,
.card-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 22px;
}
.card-grid {
    grid-template-columns: repeat(3, 1fr);
}
.lesson-card {
    display: block;
    padding: 25px;
    background: white;
    border: 1px solid #e0e8ea;
    border-radius: 12px;
    color: inherit;
    transition:
        transform 0.15s,
        border-color 0.15s;
}
.lesson-card:hover {
    transform: translateY(-3px);
    border-color: #91bfb0;
    text-decoration: none;
}
.lesson-card .number {
    font-size: 12px;
    color: #148476;
    background: #eaf5ee;
    display: inline-block;
    padding: 6px 9px;
    border-radius: 5px;
}
.lesson-card h2 {
    font-size: 18px;
    margin: 20px 0 10px;
}
.lesson-card p {
    font-size: 13px;
    margin: 0;
}
.lesson-card small {
    display: block;
    margin-top: 18px;
    color: #11816e;
}
.hero {
    background: #103d40;
    color: white;
    border-radius: 16px;
    padding: 34px;
    margin-bottom: 27px;
}
.hero p {
    color: #bad2d0;
    max-width: 740px;
}
.hero h1 {
    font-size: 40px;
}
.hero a {
    color: #cbf5e1;
}
.hero .eyebrow {
    color: #a4d3c3;
    margin: 0;
}
label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 18px;
}
input,
textarea,
select {
    display: block;
    width: 100%;
    font: inherit;
    color: #193c43;
    border: 1px solid #ccdadc;
    border-radius: 7px;
    padding: 11px 12px;
    margin-top: 8px;
    max-width: 100%;
}
textarea,
pre,
code {
    font-family: ui-monospace, SFMono-Regular, Consolas, monospace;
    font-size: 12px;
}
textarea {
    line-height: 1.6;
    resize: vertical;
}
input:focus,
textarea:focus {
    outline: 2px solid #91c8b8;
    outline-offset: 2px;
}
button,
.button {
    display: inline-block;
    border: 0;
    background: #117c72;
    color: white;
    font: 600 13px system-ui;
    padding: 12px 18px;
    border-radius: 7px;
    cursor: pointer;
}
button:hover {
    background: #0c655e;
}
.secondary {
    background: #e8f1ed;
    color: #276f63;
}
.small {
    font-size: 12px;
}
.source-links > div {
    display: flex;
    justify-content: space-between;
    gap: 18px;
    border-bottom: 1px solid #e8eeee;
    padding: 12px 0;
    font:
        12px ui-monospace,
        monospace;
    overflow-wrap: anywhere;
}
.source-links .small {
    white-space: nowrap;
}
pre {
    background: #f2f6f6;
    border: 1px solid #e0e9e9;
    border-radius: 8px;
    padding: 18px;
    line-height: 1.75;
    white-space: pre-wrap;
    overflow-wrap: anywhere;
    max-height: 550px;
    overflow: auto;
}
pre.result {
    border-left: 4px solid #57a895;
}
.error {
    padding: 15px;
    background: #fff0ed;
    color: #a34e3d;
    border: 1px solid #efd3cb;
    border-radius: 7px;
    margin: 16px 0;
}
.success {
    padding: 15px;
    background: #e9f5ee;
    color: #2a7b58;
    border-radius: 7px;
}
.note {
    background: #edf5f8;
    padding: 16px;
    border-radius: 8px;
    color: #496f7f;
    font-size: 13px;
    line-height: 1.8;
}
.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}
.metric-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    margin-top: 20px;
}
.metric {
    padding: 25px;
    border-radius: 10px;
    background: #e8f4ed;
    border: 1px solid #cce6d8;
}
.metric.blue {
    background: #edf3fb;
    border-color: #dce6f4;
}
.metric.amber {
    background: #fff6df;
    border-color: #f2e6c5;
}
.metric span {
    display: block;
    font-size: 12px;
    color: #607c7c;
}
.metric strong {
    font-size: 32px;
    display: block;
    margin-top: 13px;
}
.metric small {
    font-size: 12px;
    font-weight: 400;
}
.browser-stage {
    padding: 30px;
    background: #e9f5f0;
    border-radius: 9px;
}
.browser-stage.blue {
    background: #e7f0fa;
}
.browser-stage.amber {
    background: #fff3d6;
}
.live-value {
    font-size: 45px;
    font-weight: 700;
    color: #147d71;
}
table {
    width: 100%;
    border-collapse: collapse;
    font-size: 12px;
    margin: 18px 0;
}
td,
th {
    text-align: left;
    padding: 13px;
    border-bottom: 1px solid #e0e9e9;
    overflow-wrap: anywhere;
}
th {
    background: #f2f6f7;
}
.table-wrap {
    overflow: auto;
}
footer {
    font-size: 11px;
    color: #899da1;
    display: flex;
    justify-content: space-between;
    margin-top: 30px;
}
code {
    background: #edf3f3;
    padding: 2px 5px;
    border-radius: 4px;
    overflow-wrap: anywhere;
}
.guide-links {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    margin: 20px 0;
}
svg {
    max-width: 100%;
    height: auto;
}
.diagram {
    display: flex;
    gap: 12px;
    align-items: center;
    flex-wrap: wrap;
}
.diagram span {
    padding: 15px;
    background: #eef6f3;
    border-radius: 7px;
    font-size: 13px;
}
@media (max-width: 800px) {
    .card-grid {
        grid-template-columns: 1fr 1fr;
    }
    .help-grid {
        grid-template-columns: 1fr;
    }
    .top {
        padding: 0 20px;
    }
    .hero h1,
    h1 {
        font-size: 30px;
    }
    .metric-grid {
        grid-template-columns: 1fr;
    }
}
@media (max-width: 520px) {
    .top nav {
        gap: 12px;
        font-size: 11px;
    }
    .brand {
        font-size: 15px;
    }
    .card-grid,
    .form-row {
        grid-template-columns: 1fr;
    }
    main {
        padding: 25px 16px;
    }
    .panel,
    .hero {
        padding: 23px;
    }
    .source-links > div {
        align-items: flex-start;
    }
    footer {
        gap: 14px;
        flex-direction: column;
    }
}

.hero a.button.secondary {
    color: #19584f;
    background: #e8f1ed;
}
.callout {
    border-left: 4px solid #57a895;
    background: #edf6f1;
    padding: 18px;
    border-radius: 7px;
    margin: 20px 0;
}