/* VCS Platform — front-end stylesheet (FastAPI side).
 *
 * Design tokens:
 *   --vcs-primary:     #2563eb  blue
 *   --vcs-primary-dk:  #1e3a8a  deep blue (gradient start)
 *   --vcs-accent:      #7c3aed  purple  (gradient end)
 *   --vcs-ink:         #0f172a  body text
 *   --vcs-muted:       #64748b  secondary text
 *   --vcs-border:      #e2e8f0
 *   --vcs-bg:          #f8fafc
 */

:root {
    --vcs-primary:     #2563eb;
    --vcs-primary-dk:  #1e3a8a;
    --vcs-accent:      #7c3aed;
    --vcs-ink:         #0f172a;
    --vcs-muted:       #64748b;
    --vcs-muted-2:     #94a3b8;
    --vcs-border:      #e2e8f0;
    --vcs-bg:          #f8fafc;
    --vcs-surface:     #ffffff;
    --vcs-danger:      #dc2626;
    --vcs-radius:      10px;
    --vcs-radius-lg:   14px;
    --vcs-shadow-sm:   0 1px 3px rgba(15, 23, 42, 0.06);
    --vcs-shadow-md:   0 4px 12px rgba(15, 23, 42, 0.08);
    --vcs-shadow-lg:   0 10px 30px rgba(15, 23, 42, 0.12);
}

* {
    box-sizing: border-box;
}

html, body {
    margin: 0;
    padding: 0;
    font-family: 'Inter', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
    color: var(--vcs-ink);
    background: var(--vcs-bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--vcs-primary);
    text-decoration: none;
}
a:hover {
    text-decoration: underline;
}

/* ── Buttons ────────────────────────────────────────────────────────────── */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px 18px;
    font-family: inherit;
    font-size: 0.9rem;
    font-weight: 600;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    text-decoration: none;
    transition: opacity 0.15s, background 0.15s, transform 0.08s;
    line-height: 1.2;
    letter-spacing: 0.01em;
}
.btn:active {
    transform: translateY(1px);
}

.btn-primary {
    background: linear-gradient(135deg, var(--vcs-primary) 0%, var(--vcs-accent) 100%);
    color: #ffffff;
}
.btn-primary:hover {
    opacity: 0.9;
    text-decoration: none;
}

.btn-outline {
    background: transparent;
    color: var(--vcs-primary);
    border: 1.5px solid var(--vcs-primary);
}
.btn-outline:hover {
    background: rgba(37, 99, 235, 0.06);
    text-decoration: none;
}

.btn-ghost {
    background: transparent;
    color: var(--vcs-muted);
    border: none;
}
.btn-ghost:hover {
    color: var(--vcs-ink);
    text-decoration: none;
}

.btn-block {
    width: 100%;
    padding: 12px 18px;
}

/* ── Landing ────────────────────────────────────────────────────────────── */

.landing {
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 24px;
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 0;
    border-bottom: 1px solid var(--vcs-border);
}
.brand {
    font-weight: 800;
    font-size: 1.1rem;
    color: var(--vcs-primary-dk);
    letter-spacing: -0.01em;
}

.hero {
    padding: 72px 0 48px 0;
}
.hero h1 {
    font-size: clamp(1.9rem, 4vw, 2.8rem);
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -0.02em;
    margin: 0 0 20px 0;
}
.hero .accent {
    background: linear-gradient(120deg, var(--vcs-primary) 0%, var(--vcs-accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero .lede {
    font-size: 1.1rem;
    line-height: 1.6;
    color: var(--vcs-muted);
    max-width: 640px;
    margin: 0 0 32px 0;
}
.cta-row {
    display: flex;
    gap: 12px;
    align-items: center;
    flex-wrap: wrap;
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
    padding: 24px 0 64px 0;
    border-top: 1px solid var(--vcs-border);
}
.feature {
    background: var(--vcs-surface);
    padding: 24px;
    border-radius: var(--vcs-radius-lg);
    border: 1px solid var(--vcs-border);
    box-shadow: var(--vcs-shadow-sm);
}
.feature-num {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--vcs-primary) 0%, var(--vcs-accent) 100%);
    color: #ffffff;
    font-weight: 700;
    font-size: 0.85rem;
    margin-bottom: 12px;
}
.feature h3 {
    margin: 0 0 8px 0;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--vcs-ink);
}
.feature p {
    margin: 0;
    color: var(--vcs-muted);
    font-size: 0.92rem;
    line-height: 1.55;
}

.footer {
    padding: 24px 0;
    border-top: 1px solid var(--vcs-border);
    color: var(--vcs-muted-2);
    font-size: 0.82rem;
}

/* ── Auth (login) ───────────────────────────────────────────────────────── */

.auth-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    background:
        radial-gradient(ellipse at top left, rgba(37, 99, 235, 0.08), transparent 50%),
        radial-gradient(ellipse at bottom right, rgba(124, 58, 237, 0.08), transparent 50%),
        var(--vcs-bg);
}

.auth-card {
    width: 100%;
    max-width: 420px;
    background: var(--vcs-surface);
    border-radius: var(--vcs-radius-lg);
    box-shadow: var(--vcs-shadow-lg);
    overflow: hidden;
    border: 1px solid var(--vcs-border);
}

.auth-header {
    background: linear-gradient(120deg, var(--vcs-primary-dk) 0%, #4c1d95 100%);
    padding: 28px 32px 22px 32px;
    text-align: center;
    color: #ffffff;
}
.auth-brand {
    display: block;
    font-size: 1.25rem;
    font-weight: 700;
    color: #ffffff;
    letter-spacing: -0.01em;
    text-decoration: none;
}
.auth-brand:hover {
    text-decoration: none;
    opacity: 0.92;
}
.auth-subtitle {
    margin: 4px 0 0 0;
    color: #cbd5e1;
    font-size: 0.85rem;
}

.auth-body {
    padding: 24px 32px 28px 32px;
}
.auth-title {
    margin: 0 0 18px 0;
    font-size: 1rem;
    font-weight: 700;
    color: var(--vcs-ink);
}

.auth-form {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.field {
    display: flex;
    flex-direction: column;
    gap: 6px;
}
.field-label {
    font-size: 0.82rem;
    font-weight: 600;
    color: var(--vcs-ink);
}
.field input {
    appearance: none;
    width: 100%;
    padding: 10px 12px;
    font-family: inherit;
    font-size: 0.95rem;
    color: var(--vcs-ink);
    background: #ffffff;
    border: 1px solid var(--vcs-border);
    border-radius: 8px;
    transition: border-color 0.15s, box-shadow 0.15s;
}
.field input:hover {
    border-color: var(--vcs-muted-2);
}
.field input:focus {
    outline: none;
    border-color: var(--vcs-primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.14);
}
.field input::placeholder {
    color: var(--vcs-muted-2);
}

.auth-help {
    text-align: center;
    margin: 14px 0 0 0;
    color: var(--vcs-muted);
    font-size: 0.82rem;
}

/* ── Alerts ─────────────────────────────────────────────────────────────── */

.alert {
    padding: 10px 12px;
    border-radius: 8px;
    font-size: 0.88rem;
    margin-bottom: 14px;
    border-left: 4px solid;
}
.alert-error {
    background: rgba(220, 38, 38, 0.07);
    border-left-color: var(--vcs-danger);
    color: #991b1b;
}

/* ── Small screens ──────────────────────────────────────────────────────── */

@media (max-width: 480px) {
    .hero {
        padding: 48px 0 32px 0;
    }
    .auth-card {
        max-width: 100%;
    }
    .auth-header {
        padding: 24px 20px 18px 20px;
    }
    .auth-body {
        padding: 20px;
    }
}