:root {
    color-scheme: light;
    --bg: #f4f6f2;
    --surface: #ffffff;
    --text: #17201b;
    --muted: #65716b;
    --border: #d7ded8;
    --primary: #106b5d;
    --primary-strong: #0a4f45;
    --primary-soft: #e1f3ee;
    --warning: #8a5a00;
    --danger: #b42318;
    --shadow: 0 20px 55px rgba(21, 31, 26, 0.12);
}

* {
    box-sizing: border-box;
}

[hidden] {
    display: none !important;
}

body {
    margin: 0;
    min-height: 100dvh;
    background: var(--bg);
    color: var(--text);
    font-family: "Microsoft YaHei", "PingFang SC", "Segoe UI", sans-serif;
    line-height: 1.5;
}

button,
input {
    font: inherit;
}

.shell {
    width: min(100%, 760px);
    min-height: 100dvh;
    margin: 0 auto;
    padding: 32px 16px;
    display: grid;
    place-items: center;
}

.tool-panel {
    width: 100%;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    box-shadow: var(--shadow);
    padding: clamp(24px, 5vw, 44px);
}

.masthead {
    display: grid;
    gap: 4px;
    margin-bottom: 28px;
}

.eyebrow {
    margin: 0;
    color: var(--primary);
    font-size: 13px;
    font-weight: 700;
    text-transform: uppercase;
}

h1 {
    margin: 0;
    font-size: clamp(30px, 5vw, 44px);
    line-height: 1.15;
    letter-spacing: 0;
}

.code-form {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 14px;
    align-items: end;
}

.field {
    display: grid;
    gap: 8px;
}

label,
.result-label,
dt {
    color: var(--muted);
    font-size: 14px;
    font-weight: 700;
}

input {
    width: 100%;
    min-height: 52px;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0 16px;
    color: var(--text);
    background: #fbfcfb;
    outline: none;
}

input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(16, 107, 93, 0.18);
}

.field-error {
    min-height: 21px;
    margin: 0;
    color: var(--danger);
    font-size: 14px;
}

.limit-note {
    margin: 10px 0 0;
    color: var(--muted);
    font-size: 14px;
}

.primary-button,
.copy-button {
    min-height: 52px;
    border: 0;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 700;
}

.primary-button {
    min-width: 132px;
    padding: 0 22px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    color: #ffffff;
    background: var(--primary);
}

.primary-button:hover:not(:disabled),
.copy-button:hover:not(:disabled) {
    background: var(--primary-strong);
}

.primary-button:disabled,
.copy-button:disabled {
    cursor: not-allowed;
    opacity: 0.56;
}

.spinner {
    width: 18px;
    height: 18px;
    border: 2px solid rgba(255, 255, 255, 0.4);
    border-top-color: #ffffff;
    border-radius: 50%;
    display: none;
    animation: spin 0.8s linear infinite;
}

.primary-button.is-loading .spinner {
    display: inline-block;
}

.status {
    min-height: 48px;
    margin-top: 18px;
    padding: 12px 14px;
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--muted);
    background: #fbfcfb;
}

.status.is-waiting {
    color: var(--warning);
    background: #fff8e6;
    border-color: #ecd294;
}

.status.is-error {
    color: var(--danger);
    background: #fff3f0;
    border-color: #f4b9b1;
}

.status.is-success {
    color: var(--primary-strong);
    background: var(--primary-soft);
    border-color: #a4d9cb;
}

.result {
    margin-top: 18px;
    padding: 20px;
    border: 1px solid var(--border);
    border-radius: 8px;
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 16px;
    align-items: center;
}

.result-label,
.code-value {
    margin: 0;
}

.code-value {
    min-height: 58px;
    font-family: "Cascadia Mono", "Consolas", monospace;
    font-size: clamp(38px, 12vw, 58px);
    line-height: 1;
    letter-spacing: 0;
    color: var(--text);
}

.copy-button {
    min-width: 92px;
    padding: 0 18px;
    color: #ffffff;
    background: var(--primary);
}

.meta {
    margin: 18px 0 0;
    padding-top: 16px;
    border-top: 1px solid var(--border);
    display: grid;
    gap: 10px;
}

.meta div {
    display: grid;
    grid-template-columns: 90px 1fr;
    gap: 12px;
}

dd {
    margin: 0;
    min-width: 0;
    overflow-wrap: anywhere;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

@media (max-width: 640px) {
    .shell {
        padding: 16px;
        align-items: start;
    }

    .tool-panel {
        padding: 22px;
    }

    .code-form,
    .result,
    .meta div {
        grid-template-columns: 1fr;
    }

    .primary-button,
    .copy-button {
        width: 100%;
    }
}

@media (prefers-reduced-motion: reduce) {
    .spinner {
        animation: none;
    }
}