:root {
    --bg: #f5f7fb;
    --surface: #ffffff;
    --surface-subtle: #f8fafc;
    --border: #d9e1ec;
    --border-strong: #c7d2e2;
    --text: #172033;
    --muted: #667085;
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --danger: #b42318;
    --danger-bg: #fef3f2;
    --danger-border: #fecdca;
    --success: #067647;
    --success-bg: #ecfdf3;
    --success-border: #abefc6;
    --warning: #b54708;
    --warning-bg: #fffaeb;
    --warning-border: #fedf89;
    --info: #175cd3;
    --info-bg: #eff8ff;
    --info-border: #b2ddff;
    --shadow: 0 18px 45px rgba(17, 24, 39, 0.08);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    background: var(--bg);
    color: var(--text);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
    font-size: 16px;
    line-height: 1.5;
}

button,
input,
select {
    font: inherit;
}

.navbar {
    min-height: 64px;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    background: var(--surface);
    border-bottom: 1px solid var(--border);
}

.navbar-brand {
    color: var(--text);
    font-size: 18px;
    font-weight: 700;
    white-space: nowrap;
}

.container {
    width: min(100% - 32px, 960px);
    margin: 0 auto;
    padding: 32px 0;
}

.auth-container {
    width: min(100% - 32px, 420px);
    margin: 0 auto;
    padding: 72px 0;
}

.card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.card-body {
    padding: 24px;
}

.card-title {
    margin: 0 0 20px;
    font-size: 20px;
    font-weight: 700;
}

.form-group {
    margin-bottom: 16px;
}

.form-help {
    margin-top: 6px;
    color: var(--muted);
    font-size: 13px;
}

.form-control {
    width: 100%;
    min-height: 44px;
    padding: 10px 12px;
    color: var(--text);
    background: var(--surface);
    border: 1px solid var(--border-strong);
    border-radius: 8px;
    outline: none;
    transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.password-field {
    position: relative;
}

.password-field .form-control {
    padding-right: 68px;
}

.password-toggle {
    position: absolute;
    right: 8px;
    top: 50%;
    min-width: 52px;
    min-height: 30px;
    padding: 5px 8px;
    color: var(--primary);
    background: transparent;
    border: 0;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    transform: translateY(-50%);
}

.password-toggle:hover {
    background: #eef4ff;
}

.form-control:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.14);
}

.btn {
    min-height: 40px;
    padding: 9px 16px;
    border: 1px solid transparent;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    text-align: center;
    background: transparent;
    transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
}

.btn:disabled {
    cursor: not-allowed;
    opacity: 0.55;
}

.btn-primary {
    color: #ffffff;
    background: var(--primary);
    border-color: var(--primary);
}

.btn-primary:hover:not(:disabled) {
    background: var(--primary-hover);
    border-color: var(--primary-hover);
}

.btn-secondary {
    color: var(--text);
    background: var(--surface-subtle);
    border-color: var(--border);
}

.btn-secondary:hover:not(:disabled) {
    background: #eef4ff;
    border-color: #b2ccff;
}

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

.btn-danger:hover:not(:disabled) {
    background: #912018;
    border-color: #912018;
}

.btn-compact {
    min-height: 34px;
    padding: 6px 10px;
    font-size: 14px;
}

.btn-menu {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    min-height: 38px;
    padding: 8px 12px;
    color: var(--text);
    background: var(--surface-subtle);
    border: 1px solid var(--border);
}

.btn-menu:hover,
.btn-menu[aria-expanded="true"] {
    background: #eef4ff;
    border-color: #b2ccff;
}

.account {
    position: relative;
}

.account-caret {
    width: 7px;
    height: 7px;
    border-right: 1.5px solid var(--muted);
    border-bottom: 1.5px solid var(--muted);
    transform: translateY(-2px) rotate(45deg);
    transition: transform 0.15s ease;
}

.btn-menu[aria-expanded="true"] .account-caret {
    transform: translateY(2px) rotate(225deg);
}

.account-menu {
    position: absolute;
    right: 0;
    top: calc(100% + 8px);
    z-index: 20;
    min-width: 180px;
    padding: 6px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    box-shadow: 0 18px 36px rgba(15, 23, 42, 0.14);
}

.account-menu[hidden] {
    display: none;
}

.menu-item {
    width: 100%;
    min-height: 38px;
    padding: 9px 10px;
    display: block;
    color: var(--text);
    text-align: left;
    background: transparent;
    border: 0;
    border-radius: 6px;
    cursor: pointer;
}

.menu-item[hidden] {
    display: none;
}

.menu-item:hover:not(:disabled) {
    background: var(--surface-subtle);
}

.menu-item:disabled {
    color: var(--muted);
    cursor: not-allowed;
}

.menu-item-danger {
    color: var(--danger);
}

.menu-divider {
    height: 1px;
    margin: 6px 4px;
    background: var(--border);
}

.stack {
    display: grid;
    gap: 24px;
}

.form-panel {
    width: min(100%, 560px);
    margin: 24px auto 0;
}

.admin-layout {
    display: grid;
    gap: 24px;
}

.admin-tabs {
    display: inline-flex;
    gap: 4px;
    margin-bottom: 20px;
    padding: 4px;
    background: var(--surface-subtle);
    border: 1px solid var(--border);
    border-radius: 8px;
}

.admin-tab {
    min-height: 34px;
    padding: 7px 14px;
    color: var(--muted);
    background: transparent;
    border: 0;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 700;
}

.admin-tab:hover {
    color: var(--text);
    background: #eef4ff;
}

.admin-tab.is-active {
    color: var(--text);
    background: var(--surface);
    box-shadow: 0 1px 3px rgba(15, 23, 42, 0.12);
}

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

.admin-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 18px;
}

.admin-header .card-title {
    margin-bottom: 0;
}

.admin-toolbar {
    margin-bottom: 16px;
}

.checkbox-row {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--text);
    font-weight: 600;
}

.user-list {
    display: grid;
    gap: 10px;
}

.user-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 12px;
    background: var(--surface-subtle);
    border: 1px solid var(--border);
    border-radius: 8px;
}

.user-name {
    font-weight: 700;
}

.user-meta {
    color: var(--muted);
    font-size: 14px;
}

.user-actions {
    display: inline-flex;
    gap: 8px;
}

.modal-backdrop {
    position: fixed;
    inset: 0;
    z-index: 50;
    display: grid;
    place-items: center;
    padding: 24px;
    background: rgba(15, 23, 42, 0.42);
}

.modal-backdrop[hidden] {
    display: none;
}

.modal {
    width: min(100%, 420px);
    padding: 22px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    box-shadow: 0 24px 60px rgba(15, 23, 42, 0.24);
}

.modal-title {
    margin: 0 0 8px;
    font-size: 18px;
    font-weight: 700;
}

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

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    margin-top: 22px;
}

.toast-container {
    position: fixed;
    right: 24px;
    top: 80px;
    z-index: 70;
    width: min(320px, calc(100vw - 32px));
}

.toast {
    padding: 12px 14px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 8px;
    box-shadow: 0 18px 40px rgba(15, 23, 42, 0.18);
    font-weight: 600;
}

.toast-success {
    color: var(--success);
    background: var(--success-bg);
    border-color: var(--success-border);
}

.toast-danger {
    color: var(--danger);
    background: var(--danger-bg);
    border-color: var(--danger-border);
}

.action-row {
    display: flex;
    justify-content: center;
}

.alert {
    padding: 12px 14px;
    border: 1px solid transparent;
    border-radius: 8px;
}

.alert-secondary {
    color: var(--muted);
    background: var(--surface-subtle);
    border-color: var(--border);
}

.alert-success {
    color: var(--success);
    background: var(--success-bg);
    border-color: var(--success-border);
}

.alert-warning {
    color: var(--warning);
    background: var(--warning-bg);
    border-color: var(--warning-border);
}

.alert-danger {
    color: var(--danger);
    background: var(--danger-bg);
    border-color: var(--danger-border);
}

.alert-info {
    color: var(--info);
    background: var(--info-bg);
    border-color: var(--info-border);
}

.mt-3 {
    margin-top: 16px;
}

@media (max-width: 560px) {
    .navbar {
        padding: 0 16px;
    }

    .navbar-brand {
        font-size: 16px;
    }

    .btn-menu {
        max-width: 190px;
    }

    #currentUsername {
        overflow: hidden;
        text-overflow: ellipsis;
        white-space: nowrap;
    }

    .admin-header {
        align-items: stretch;
        flex-direction: column;
    }

    .user-row {
        align-items: flex-start;
        flex-direction: column;
    }
}