:root {
    --bg: #f4f4f5;
    --surface: #ffffff;
    --surface-2: #fafafa;
    --border: #e4e4e7;
    --border-strong: #d4d4d8;
    --text: #18181b;
    --text-muted: #71717a;
    --brand: #18181b;
    --brand-strong: #000000;
    --danger: #dc2626;
    --gray-400: #a1a1aa;
    --gray-600: #52525b;
    --gray-900: #18181b;
    --radius: 16px;
    --radius-sm: 10px;
    --shadow: 0 20px 45px rgba(24, 24, 27, .10), 0 2px 6px rgba(24, 24, 27, .05);
    --mono: ui-monospace, "Cascadia Mono", Consolas, "SF Mono", Menlo, monospace;
    --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    -webkit-text-size-adjust: 100%;
}

body {
    margin: 0;
    padding: 24px 16px 32px;
    min-height: 100vh;
    font-family: var(--sans);
    font-size: 16px;
    line-height: 1.5;
    color: var(--text);
    background: var(--bg);
    background-image: radial-gradient(1100px 550px at 10% -12%, #ffffff 0%, transparent 62%), radial-gradient(900px 500px at 100% 0%, #ebebed 0%, transparent 58%);
    background-attachment: fixed;
}

p {
    margin: 0;
}

a {
    color: var(--brand);
    text-decoration: none;
    border-bottom: 1px solid var(--border-strong);
    transition: color .15s ease, border-color .15s ease;
}

    a:hover,
    a:focus-visible {
        color: var(--brand-strong);
        border-bottom-color: currentColor;
    }

:focus-visible {
    outline: 2px solid var(--brand);
    outline-offset: 2px;
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    margin: -1px;
    padding: 0;
    overflow: hidden;
    clip: rect(0 0 0 0);
    clip-path: inset(50%);
    white-space: nowrap;
    border: 0;
}

.container {
    width: 100%;
    max-width: 780px;
    margin: 0 auto;
    padding: 26px 28px 20px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

/* Header ------------------------------------------------------------- */

#header {
    margin: 0 0 18px;
}

    #header h1 {
        margin: 0;
        font-size: clamp(22px, 3.6vw, 28px);
        font-weight: 650;
        letter-spacing: -.02em;
        line-height: 1.2;
    }

.trust {
    display: flex;
    align-items: baseline;
    gap: 7px;
    margin: 6px 0 0;
    color: var(--text-muted);
    font-size: 13.5px;
}

.trust-icon {
    flex: none;
}

/* Result ------------------------------------------------------------- */

#results {
    margin: 0 0 14px;
}

.result-row {
    display: flex;
    gap: 8px;
    align-items: stretch;
}

#password {
    flex: 1 1 auto;
    min-width: 0;
    padding: 12px 14px;
    font-family: var(--mono);
    font-size: 16px;
    font-weight: 600;
    color: var(--text);
    background: var(--surface-2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    box-shadow: inset 0 1px 2px rgba(24, 24, 27, .05);
}

    #password:focus {
        border-color: var(--gray-900);
        box-shadow: 0 0 0 3px rgba(24, 24, 27, .12);
        outline: none;
    }

.meter {
    display: flex;
    align-items: center;
    gap: 10px;
    margin: 8px 0 0;
}

.meter-track {
    flex: 1 1 auto;
    height: 7px;
    background: #e4e4e7;
    border-radius: 999px;
    overflow: hidden;
}

.meter-fill {
    width: 0;
    height: 100%;
    border-radius: 999px;
    background: var(--text-muted);
    transition: width .2s ease, background-color .2s ease;
}

    /* Weak keeps a warning colour; the rest darken as strength increases. */
    .meter-fill.is-weak {
        background: var(--danger);
    }

    .meter-fill.is-good {
        background: var(--gray-400);
    }

    .meter-fill.is-strong {
        background: var(--gray-600);
    }

    .meter-fill.is-very-strong {
        background: var(--gray-900);
    }

.meter-label {
    flex: none;
    min-width: 168px;
    text-align: right;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-muted);
}

.phonetic {
    margin: 10px 0 0;
    min-height: 1.2em;
    color: var(--text-muted);
    font-family: var(--mono);
    font-size: 12.5px;
    word-break: break-word;
}

/* Generator modes ---------------------------------------------------- */

.mode-tabs {
    position: relative;
    display: flex;
    gap: 24px;
    margin: -2px 0 18px;
    border-bottom: 1px solid var(--border);
}

.mode-tab {
    position: relative;
    margin: 0 0 -1px;
    padding: 2px 0 10px;
    font: inherit;
    font-size: 14px;
    font-weight: 650;
    color: var(--text-muted);
    background: transparent;
    border: 0;
    cursor: pointer;
    transition: color .18s ease;
}

    .mode-tab::after {
        content: "";
        position: absolute;
        right: 0;
        bottom: 0;
        left: 0;
        height: 2px;
        background: var(--gray-900);
        transform: scaleX(0);
        transform-origin: center;
        transition: transform .2s ease;
    }

    .mode-tab:hover,
    .mode-tab[aria-selected="true"] {
        color: var(--text);
    }

    .mode-tab[aria-selected="true"]::after {
        transform: scaleX(1);
    }

    .mode-tab:focus-visible {
        outline: 2px solid var(--gray-900);
        outline-offset: 4px;
        border-radius: 2px;
    }

.generator-panel[hidden] {
    display: none;
}

.passphrase-row {
    display: grid;
    grid-template-columns: 105px minmax(0, 1fr);
    align-items: center;
    gap: 10px;
    margin: 0 0 14px;
    font-size: 13px;
}

    .passphrase-row label {
        font-weight: 600;
    }

    .passphrase-row input[type="range"] {
        flex: 1;
    }

    .passphrase-row output {
        font-family: var(--mono);
        font-weight: 700;
    }

    .passphrase-row select {
        width: 100%;
        padding: 7px 10px;
        font: inherit;
        font-size: 13px;
        color: var(--text);
        background: var(--surface);
        border: 1px solid var(--border);
        border-radius: var(--radius-sm);
    }

.passphrase-options {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin: 4px 0 0;
    padding: 12px 0 0;
    border-top: 1px solid var(--border);
}

    .passphrase-options label {
        display: flex;
        align-items: center;
        gap: 6px;
        font-size: 13px;
        cursor: pointer;
    }

    .passphrase-options input[type="checkbox"] {
        width: 16px;
        height: 16px;
    }

.mode-note {
    margin: 10px 0 0;
    color: var(--text-muted);
    font-size: 12px;
}

/* Options ------------------------------------------------------------ */

#options {
    padding: 16px 18px 18px;
    background: var(--surface-2);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    box-shadow: inset 0 1px 0 #fff;
}

.length-row {
    display: grid;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    gap: 10px;
}

    .length-row > label {
        font-size: 13px;
        font-weight: 600;
        white-space: nowrap;
    }

    .length-row output {
        display: inline-block;
        min-width: 3ch;
        font-family: var(--mono);
        color: var(--text);
        font-weight: 700;
    }

input[type="range"] {
    width: 100%;
    accent-color: var(--gray-900);
    cursor: pointer;
}

.presets {
    display: flex;
    gap: 6px;
}

.preset {
    padding: 5px 9px;
    font-family: var(--mono);
    font-size: 12px;
    color: var(--text-muted);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 999px;
    cursor: pointer;
    transition: color .15s ease, background .15s ease, border-color .15s ease;
}

    .preset:hover {
        color: var(--text);
        border-color: var(--gray-400);
    }

    .preset[aria-pressed="true"] {
        color: #fff;
        background: var(--gray-900);
        border-color: var(--gray-900);
    }

.sets {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
    margin: 12px 0 0;
    padding: 12px 0 0;
    border-top: 1px solid var(--border);
}

    .sets label {
        display: flex;
        align-items: center;
        gap: 7px;
        font-size: 13px;
        cursor: pointer;
    }

input[type="checkbox"] {
    flex: none;
    width: 17px;
    height: 17px;
    accent-color: var(--gray-900);
    cursor: pointer;
}

.password-options {
    display: grid;
    gap: 9px;
    margin: 12px 0 0;
    padding: 12px 0 0;
    border-top: 1px solid var(--border);
}

.advanced-option {
    display: flex;
    align-items: flex-start;
    gap: 8px;
    font-size: 13px;
    cursor: pointer;
}

    .advanced-option .note {
        display: block;
    }

.note {
    color: var(--text-muted);
    font-size: 11px;
    font-family: var(--mono);
    word-break: break-word;
}

.advanced-links {
    margin: 2px 0 0;
}

.shared-options {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 10px 18px;
    margin: 14px 0 0;
    padding: 12px 0 0;
    border-top: 1px solid var(--border);
    font-size: 13px;
}

    .shared-options label {
        display: flex;
        align-items: center;
        gap: 7px;
        cursor: pointer;
    }

.link-button {
    display: inline;
    margin: 0;
    padding: 0;
    font: inherit;
    font-size: 13.5px;
    color: var(--text-muted);
    background: none;
    border: 0;
    border-bottom: 1px solid var(--border-strong);
    cursor: pointer;
    transition: color .15s ease, border-color .15s ease;
}

    .link-button:hover,
    .link-button:focus-visible {
        color: var(--brand-strong);
        border-bottom-color: currentColor;
    }

/* Buttons ------------------------------------------------------------ */

.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    cursor: pointer;
    user-select: none;
    font-family: inherit;
    font-size: 14px;
    font-weight: 600;
    color: var(--text);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    box-shadow: 0 1px 2px rgba(24, 24, 27, .08);
    transition: background .15s ease, border-color .15s ease, filter .15s ease, transform .05s ease;
}

    .button:hover {
        border-color: var(--gray-400);
        background: #f4f4f5;
    }

    .button:active {
        transform: translateY(1px);
    }

#btnCopy {
    flex: none;
    min-width: 100px;
    padding: 10px 14px;
}

    #btnCopy.is-copied,
    #btnCopy.is-copied:hover {
        color: #fff;
        background: var(--gray-900);
        border-color: var(--gray-900);
        box-shadow: 0 8px 18px rgba(24, 24, 27, .28);
        animation: copy-pop .25s ease;
    }

    #btnCopy.is-failed,
    #btnCopy.is-failed:hover {
        color: #fff;
        background: var(--danger);
        border-color: var(--danger);
        box-shadow: 0 8px 18px rgba(220, 38, 38, .28);
    }

@keyframes copy-pop {
    0% {
        transform: scale(.94);
    }

    60% {
        transform: scale(1.04);
    }

    100% {
        transform: scale(1);
    }
}

#GeneratePassword {
    margin: 14px 0 0;
    text-align: center;
}

#btnGeneratePassword {
    width: auto;
    min-width: 140px;
    padding: 10px 18px;
    font-size: 14px;
    font-weight: 600;
    color: #fff;
    background: linear-gradient(160deg, #27272a, #09090b);
    border-color: transparent;
    box-shadow: 0 12px 26px rgba(24, 24, 27, .28);
}

    #btnGeneratePassword:hover {
        border-color: transparent;
        background: linear-gradient(160deg, #27272a, #09090b);
        filter: brightness(1.35);
    }

/* Footer ------------------------------------------------------------- */

#footer {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 12px 24px;
    margin: 22px 0 0;
    padding: 16px 2px 2px;
    border-top: 1px solid var(--border);
    color: var(--text-muted);
    font-size: 12px;
}

.footer-signature {
    display: flex;
    align-items: center;
    gap: 5px;
    min-height: 32px;
}

.author-link {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    color: var(--text);
    font-size: 12px;
    font-weight: 650;
}

    .author-link span {
        color: var(--text-muted);
        font-size: 10px;
        transition: transform .15s ease;
    }

    .author-link:hover span,
    .author-link:focus-visible span {
        transform: translate(1px, -1px);
    }

.footer-divider {
    margin: 0 2px;
    color: var(--border-strong);
}

.version {
    font-family: var(--mono);
    font-size: 10.5px;
    color: var(--text-muted);
}

.coffee-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    min-height: 32px;
    padding: 5px 11px;
    font-size: 12px;
    font-weight: 650;
    color: #1a1207;
    background: #ffca28;
    border: 1px solid #f1b900;
    border-radius: 999px;
    box-shadow: 0 2px 8px rgba(255, 187, 0, .18);
    transition: background .15s ease, border-color .15s ease, transform .15s ease;
}

    .coffee-link:hover,
    .coffee-link:focus-visible {
        color: #1a1207;
        background: #ffd24a;
        border-color: #e5ad00;
        transform: translateY(-1px);
    }

/* Responsive --------------------------------------------------------- */

@media (max-width: 700px) {
    .sets {
        grid-template-columns: repeat(2, 1fr);
    }

    .meter-label {
        min-width: 0;
    }
}

@media (max-width: 560px) {
    body {
        padding: 12px 10px 24px;
    }

    .container {
        padding: 20px 18px 16px;
    }

    #footer {
        align-items: center;
    }

    .length-row {
        grid-template-columns: 1fr;
        gap: 8px;
    }

    .passphrase-row {
        grid-template-columns: 1fr;
        gap: 7px;
    }

    .passphrase-options {
        grid-template-columns: 1fr;
    }

    .shared-options {
        align-items: flex-start;
        flex-direction: column;
    }

    .presets {
        flex-wrap: wrap;
    }

    .result-row {
        flex-direction: column;
    }

    #btnCopy {
        width: 100%;
    }

    .meter {
        flex-wrap: wrap;
    }

    .meter-label {
        text-align: left;
    }
}

@media (prefers-reduced-motion: reduce) {
    * {
        transition: none !important;
        animation: none !important;
    }
}