:root {
    --bg: #f5f6f8;
    --surface: #ffffff;
    --surface-soft: #f8f9fb;
    --text: #17191d;
    --muted: #69707d;
    --border: #e3e6eb;
    --primary: #6d4aff;
    --primary-hover: #5b39ef;
    --primary-soft: #eeeaff;
    --success: #147a55;
    --success-soft: #e8f7f1;
    --warning: #9a5b00;
    --warning-soft: #fff4dc;
    --danger: #b42318;
    --danger-soft: #fff0ee;
    --shadow: 0 12px 32px rgba(20, 24, 32, 0.06);
    color-scheme: light;
}

:root[data-theme="dark"] {
    --bg: #111318;
    --surface: #191c22;
    --surface-soft: #20242c;
    --text: #f4f5f7;
    --muted: #a5abb7;
    --border: #2c313b;
    --primary: #9a83ff;
    --primary-hover: #ad9aff;
    --primary-soft: #292341;
    --success: #69d5ad;
    --success-soft: #173329;
    --warning: #f6bd68;
    --warning-soft: #392b16;
    --danger: #ff8a80;
    --danger-soft: #3e211f;
    --shadow: 0 16px 38px rgba(0, 0, 0, 0.2);
    color-scheme: dark;
}

* { box-sizing: border-box; }

html { min-height: 100%; }

body {
    min-height: 100vh;
    margin: 0;
    color: var(--text);
    background: var(--bg);
    font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    font-size: 15px;
    line-height: 1.5;
}

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

.app-shell {
    display: grid;
    grid-template-columns: 228px minmax(0, 1fr);
    min-height: 100vh;
}

.sidebar {
    position: sticky;
    top: 0;
    height: 100vh;
    display: flex;
    flex-direction: column;
    padding: 24px 16px 18px;
    border-right: 1px solid var(--border);
    background: var(--surface);
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: var(--text);
    font-size: 16px;
    font-weight: 700;
    text-decoration: none;
}

.brand-mark {
    width: 34px;
    height: 34px;
    display: grid;
    place-items: center;
    border-radius: 10px;
    color: #fff;
    background: linear-gradient(135deg, #8066ff, #5835eb);
    box-shadow: 0 8px 18px rgba(109, 74, 255, 0.28);
}

.nav-label, .eyebrow, .step {
    margin: 0;
    color: var(--muted);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.nav-label { margin: 34px 10px 10px; }

.nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 11px;
    border-radius: 9px;
    color: var(--muted);
    text-decoration: none;
}

.nav-item.active {
    color: var(--primary);
    background: var(--primary-soft);
    font-weight: 650;
}

.nav-icon {
    width: 23px;
    height: 23px;
    display: grid;
    place-items: center;
    border: 1px solid currentColor;
    border-radius: 7px;
    font-size: 13px;
    font-weight: 800;
}

.sidebar-footer {
    margin-top: auto;
    padding-top: 18px;
    border-top: 1px solid var(--border);
}

.user-card {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 8px;
}

.user-avatar {
    width: 34px;
    height: 34px;
    display: grid;
    place-items: center;
    border-radius: 50%;
    background: var(--surface-soft);
    color: var(--muted);
    font-weight: 700;
}

.user-card strong, .user-card small { display: block; }
.user-card small { color: var(--muted); }

.link-button {
    padding: 4px 0;
    border: 0;
    color: var(--muted);
    background: transparent;
    cursor: pointer;
}

.link-button:hover { color: var(--text); }

.main {
    width: min(100%, 1040px);
    margin: 0 auto;
    padding: 42px 44px 64px;
}

.page-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 24px;
    margin-bottom: 24px;
}

h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 8px; font-size: clamp(28px, 4vw, 40px); line-height: 1.12; letter-spacing: -0.035em; }
h2 { margin-bottom: 8px; font-size: 21px; letter-spacing: -0.015em; }
h3 { margin-bottom: 10px; font-size: 15px; }
.page-description, .login-description { max-width: 640px; margin-bottom: 0; color: var(--muted); font-size: 16px; }
.eyebrow { margin-bottom: 10px; }
.step { margin-bottom: 5px; color: var(--primary); }

.theme-toggle, .secondary-button {
    min-height: 40px;
    padding: 8px 14px;
    border: 1px solid var(--border);
    border-radius: 9px;
    background: var(--surface);
    cursor: pointer;
}

.theme-toggle:hover, .secondary-button:hover { border-color: var(--primary); }

.notice {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
    padding: 13px 15px;
    border: 1px solid #dcd4ff;
    border-radius: 11px;
    background: var(--primary-soft);
    color: var(--text);
}

.notice-icon {
    flex: 0 0 auto;
    width: 22px;
    height: 22px;
    display: grid;
    place-items: center;
    border-radius: 50%;
    color: #fff;
    background: var(--primary);
    font-size: 12px;
    font-weight: 800;
}

.corpus-strip {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px 20px;
    margin: -4px 0 20px;
    padding: 0 4px;
    color: var(--muted);
    font-size: 13px;
}

.corpus-strip strong { color: var(--text); font-variant-numeric: tabular-nums; }
.corpus-status { display: inline-flex; align-items: center; gap: 7px; }
.corpus-status i { width: 7px; height: 7px; border-radius: 50%; background: var(--warning); box-shadow: 0 0 0 4px var(--warning-soft); }

.search-card, .result-card, .loading-card, .error-card {
    border: 1px solid var(--border);
    border-radius: 15px;
    background: var(--surface);
    box-shadow: var(--shadow);
}

.search-card { padding: 24px; }

.section-heading, .result-topline, .result-title-row, .form-footer, .feedback {
    display: flex;
    align-items: center;
}

.section-heading, .result-topline { justify-content: space-between; gap: 20px; }
.counter { color: var(--muted); font-variant-numeric: tabular-nums; }

textarea, .login-form input {
    width: 100%;
    border: 1px solid var(--border);
    border-radius: 11px;
    color: var(--text);
    background: var(--surface-soft);
    outline: none;
    transition: border-color 140ms ease, box-shadow 140ms ease;
}

textarea {
    min-height: 134px;
    padding: 15px 16px;
    resize: vertical;
    line-height: 1.55;
}

textarea:focus, .login-form input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 16%, transparent);
}

textarea::placeholder { color: color-mix(in srgb, var(--muted) 72%, transparent); }

.form-footer {
    justify-content: space-between;
    gap: 18px;
    margin-top: 14px;
}

.examples {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 7px;
    color: var(--muted);
    font-size: 13px;
}

.examples button, .feedback button {
    padding: 5px 9px;
    border: 1px solid var(--border);
    border-radius: 999px;
    background: var(--surface-soft);
    cursor: pointer;
}

.examples button:hover, .feedback button:hover { border-color: var(--primary); color: var(--primary); }

.primary-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    min-height: 44px;
    padding: 10px 18px;
    border: 0;
    border-radius: 10px;
    color: #fff;
    background: var(--primary);
    font-weight: 700;
    cursor: pointer;
    box-shadow: 0 8px 20px rgba(109, 74, 255, 0.22);
}

.primary-button:hover { background: var(--primary-hover); }
.primary-button:disabled { opacity: 0.65; cursor: wait; }
.full-width { width: 100%; }

.loading-card {
    display: flex;
    align-items: center;
    gap: 14px;
    margin-top: 18px;
    padding: 20px 22px;
}

.loading-card p { margin-bottom: 0; color: var(--muted); }
.spinner { width: 24px; height: 24px; border: 3px solid var(--border); border-top-color: var(--primary); border-radius: 50%; animation: spin 0.8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

.result-card { margin-top: 18px; padding: 24px; }
.result-title-row { gap: 8px; }
.status-badge, .confidence-badge { display: inline-flex; padding: 5px 9px; border-radius: 999px; font-size: 12px; font-weight: 750; }
.status-answer { color: var(--success); background: var(--success-soft); }
.status-not-found { color: var(--muted); background: var(--surface-soft); }
.status-human { color: var(--warning); background: var(--warning-soft); }
.confidence-badge { color: var(--muted); background: var(--surface-soft); }
.answer { margin: 10px 0 0; white-space: pre-wrap; font-size: 17px; line-height: 1.65; }

.warning, .login-error {
    margin-top: 18px;
    padding: 12px 14px;
    border: 1px solid color-mix(in srgb, var(--warning) 30%, var(--border));
    border-radius: 10px;
    color: var(--warning);
    background: var(--warning-soft);
}

.sources-block { margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--border); }
.sources { display: grid; gap: 9px; }
.source-card { padding: 13px 14px; border: 1px solid var(--border); border-radius: 10px; background: var(--surface-soft); }
.source-main { display: flex; justify-content: space-between; gap: 16px; }
.source-question { margin: 0; font-weight: 650; }
.source-score { flex: 0 0 auto; color: var(--muted); font-variant-numeric: tabular-nums; }
.source-meta { margin-top: 5px; color: var(--muted); font-size: 13px; }

.feedback { flex-wrap: wrap; gap: 8px; margin-top: 22px; padding-top: 18px; border-top: 1px solid var(--border); }
.feedback-message { color: var(--success); font-size: 13px; }
.error-card { margin-top: 18px; padding: 18px 20px; border-color: color-mix(in srgb, var(--danger) 35%, var(--border)); background: var(--danger-soft); color: var(--danger); }
.error-card p { margin: 4px 0 0; }

.login-page { display: grid; place-items: center; padding: 24px; }
.login-shell { width: min(100%, 430px); }
.login-card { padding: 34px; border: 1px solid var(--border); border-radius: 18px; background: var(--surface); box-shadow: var(--shadow); }
.login-brand { margin-bottom: 34px; }
.login-card h1 { font-size: 30px; }
.login-description { margin-bottom: 26px; }
.login-form { display: grid; gap: 9px; }
.login-form label { margin-top: 6px; font-weight: 650; }
.login-form input { height: 46px; padding: 10px 12px; }
.login-form .primary-button { margin-top: 12px; }
.login-error { margin: 0 0 18px; color: var(--danger); background: var(--danger-soft); border-color: color-mix(in srgb, var(--danger) 30%, var(--border)); }

.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
[hidden] { display: none !important; }

@media (max-width: 820px) {
    .app-shell { grid-template-columns: 1fr; }
    .sidebar { position: static; height: auto; flex-direction: row; align-items: center; gap: 14px; padding: 12px 16px; border-right: 0; border-bottom: 1px solid var(--border); }
    .nav-label, .sidebar-footer .user-card { display: none; }
    .sidebar nav { margin-left: auto; }
    .sidebar-footer { margin: 0; padding: 0; border: 0; }
    .link-button { padding: 8px; }
    .main { padding: 28px 18px 48px; }
}

@media (max-width: 620px) {
    .page-header, .form-footer, .section-heading, .result-topline { align-items: stretch; flex-direction: column; }
    .theme-toggle { align-self: flex-start; }
    .form-footer { margin-top: 16px; }
    .primary-button { width: 100%; }
    .search-card, .result-card { padding: 19px; }
    .examples { display: none; }
}