:root {
    --bg: #f4f6fb;
    --surface: #ffffff;
    --text: #1f2937;
    --muted: #6b7280;
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --danger: #dc2626;
    --danger-hover: #b91c1c;
    --border: #e5e7eb;
    --success-bg: #ecfdf5;
    --success-text: #047857;
    --shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.5;
}

.container {
    width: min(1100px, calc(100% - 2rem));
    margin: 0 auto;
}

.header {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 10;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 64px;
}

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text);
    text-decoration: none;
}

.nav {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.nav a {
    color: var(--muted);
    text-decoration: none;
}

.nav a.active,
.nav a:hover {
    color: var(--primary);
}

.main {
    padding: 2rem 0 3rem;
}

.footer {
    padding: 1.5rem 0 2rem;
    color: var(--muted);
    font-size: 0.9rem;
}

.page-header {
    margin-bottom: 1.5rem;
}

.page-header h1 {
    margin: 0 0 0.25rem;
    font-size: 2rem;
}

.subtitle {
    margin: 0;
    color: var(--muted);
}

.link-back {
    color: var(--primary);
    text-decoration: none;
}

.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    box-shadow: var(--shadow);
    overflow: hidden;
}

.form-card {
    padding: 1.5rem;
    max-width: 720px;
}

.table {
    width: 100%;
    border-collapse: collapse;
}

.table th,
.table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
    vertical-align: top;
}

.table th {
    background: #f9fafb;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--muted);
}

.actions-col {
    width: 220px;
    white-space: nowrap;
}

.inline-form {
    display: inline;
}

.btn {
    display: inline-block;
    border: none;
    border-radius: 10px;
    padding: 0.65rem 1rem;
    font-size: 0.95rem;
    cursor: pointer;
    text-decoration: none;
    transition: background 0.15s ease;
}

.btn-sm {
    padding: 0.45rem 0.75rem;
    font-size: 0.85rem;
}

.btn-primary {
    background: var(--primary);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-hover);
}

.btn-secondary {
    background: #eef2ff;
    color: #3730a3;
}

.btn-danger {
    background: #fee2e2;
    color: var(--danger);
}

.btn-danger:hover {
    background: #fecaca;
}

.alert {
    padding: 0.875rem 1rem;
    border-radius: 12px;
    margin-bottom: 1rem;
}

.alert-success {
    background: var(--success-bg);
    color: var(--success-text);
    border: 1px solid #a7f3d0;
}

.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    background: var(--surface);
    border: 1px dashed var(--border);
    border-radius: 16px;
}

.form-group {
    margin-bottom: 1rem;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

label {
    display: block;
    margin-bottom: 0.35rem;
    font-weight: 600;
}

.form-control {
    width: 100%;
    padding: 0.75rem 0.875rem;
    border: 1px solid var(--border);
    border-radius: 10px;
    font: inherit;
    background: white;
}

.form-control:focus {
    outline: 2px solid rgba(37, 99, 235, 0.25);
    border-color: var(--primary);
}

.form-actions {
    display: flex;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.error {
    display: block;
    margin-top: 0.35rem;
    color: var(--danger);
    font-size: 0.875rem;
}

.muted {
    color: var(--muted);
}

.small {
    font-size: 0.85rem;
}

code {
    background: #eef2ff;
    padding: 0.15rem 0.4rem;
    border-radius: 6px;
}

@media (max-width: 768px) {
    .form-row {
        grid-template-columns: 1fr;
    }

    .table,
    .table thead,
    .table tbody,
    .table th,
    .table td,
    .table tr {
        display: block;
    }

    .table thead {
        display: none;
    }

    .table tr {
        border-bottom: 1px solid var(--border);
        padding: 1rem;
    }

    .table td {
        border: none;
        padding: 0.35rem 0;
    }

    .actions-col {
        width: auto;
        margin-top: 0.75rem;
    }
}