/* =============================================
   Art direction: Khách sạn cao cấp → Tone ấm, sang trọng, tối giản
   Palette: Beige surfaces + Teal accent
   Typography: Cormorant Garamond (display) + Satoshi (body)
   Density: balanced
   ============================================= */

/* --- TOKENS --- */
:root {
  /* Type scale */
  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw, 1.125rem);
  --text-lg:   clamp(1.125rem, 1rem    + 0.75vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1.2rem  + 1.25vw, 2.25rem);

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;

  /* Radius */
  --radius-sm:   0.375rem;
  --radius-md:   0.5rem;
  --radius-lg:   0.75rem;
  --radius-xl:   1rem;
  --radius-full: 9999px;

  /* Transition */
  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Fonts */
  --font-display: 'Cormorant Garamond', Georgia, serif;
  --font-body:    'Satoshi', 'Inter', sans-serif;

  /* Content widths */
  --content-narrow:  640px;
  --content-default: 960px;
  --content-wide:    1200px;
}

/* --- LIGHT MODE --- */
:root, [data-theme="light"] {
  --color-bg:               #f7f6f2;
  --color-surface:          #f9f8f5;
  --color-surface-2:        #fbfbf9;
  --color-surface-offset:   #f3f0ec;
  --color-surface-offset-2: #edeae5;
  --color-surface-dynamic:  #e6e4df;
  --color-divider:          #dcd9d5;
  --color-border:           #d4d1ca;
  --color-text:             #28251d;
  --color-text-muted:       #7a7974;
  --color-text-faint:       #bab9b4;
  --color-text-inverse:     #f9f8f4;
  --color-primary:          #01696f;
  --color-primary-hover:    #0c4e54;
  --color-primary-active:   #0f3638;
  --color-primary-highlight:#cedcd8;
  --color-error:            #b91c1c;
  --color-error-highlight:  #fee2e2;
  --color-success:          #437a22;
  --color-success-highlight:#d4dfcc;
  --color-warning:          #964219;
  --color-warning-highlight:#ddcfc6;
  --shadow-sm: 0 1px 2px oklch(0.2 0.01 80 / 0.06);
  --shadow-md: 0 4px 12px oklch(0.2 0.01 80 / 0.08);
  --shadow-lg: 0 12px 32px oklch(0.2 0.01 80 / 0.12);
}

/* --- DARK MODE --- */
[data-theme="dark"] {
  --color-bg:               #171614;
  --color-surface:          #1c1b19;
  --color-surface-2:        #201f1d;
  --color-surface-offset:   #1d1c1a;
  --color-surface-offset-2: #22211f;
  --color-surface-dynamic:  #2d2c2a;
  --color-divider:          #262523;
  --color-border:           #393836;
  --color-text:             #cdccca;
  --color-text-muted:       #797876;
  --color-text-faint:       #5a5957;
  --color-text-inverse:     #2b2a28;
  --color-primary:          #4f98a3;
  --color-primary-hover:    #227f8b;
  --color-primary-active:   #1a626b;
  --color-primary-highlight:#313b3b;
  --color-error:            #f87171;
  --color-error-highlight:  #3b1515;
  --color-success:          #6daa45;
  --color-success-highlight:#3a4435;
  --color-warning:          #fdab43;
  --color-warning-highlight:#564b3e;
  --shadow-sm: 0 1px 2px oklch(0 0 0 / 0.2);
  --shadow-md: 0 4px 12px oklch(0 0 0 / 0.3);
  --shadow-lg: 0 12px 32px oklch(0 0 0 / 0.4);
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg:               #171614;
    --color-surface:          #1c1b19;
    --color-surface-2:        #201f1d;
    --color-surface-offset:   #1d1c1a;
    --color-surface-offset-2: #22211f;
    --color-surface-dynamic:  #2d2c2a;
    --color-divider:          #262523;
    --color-border:           #393836;
    --color-text:             #cdccca;
    --color-text-muted:       #797876;
    --color-text-faint:       #5a5957;
    --color-text-inverse:     #2b2a28;
    --color-primary:          #4f98a3;
    --color-primary-hover:    #227f8b;
    --color-primary-active:   #1a626b;
    --color-primary-highlight:#313b3b;
    --color-error:            #f87171;
    --color-error-highlight:  #3b1515;
    --color-success:          #6daa45;
    --color-success-highlight:#3a4435;
    --color-warning:          #fdab43;
    --color-warning-highlight:#564b3e;
    --shadow-sm: 0 1px 2px oklch(0 0 0 / 0.2);
    --shadow-md: 0 4px 12px oklch(0 0 0 / 0.3);
    --shadow-lg: 0 12px 32px oklch(0 0 0 / 0.4);
  }
}

/* --- BASE RESET --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html {
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  scroll-padding-top: var(--space-16);
}
body {
  min-height: 100dvh;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.6;
}
img, picture, video, canvas, svg { display: block; max-width: 100%; height: auto; }
input, button, textarea, select { font: inherit; color: inherit; }
h1,h2,h3,h4,h5,h6 { text-wrap: balance; line-height: 1.15; }
p, li { text-wrap: pretty; max-width: 72ch; }
button { cursor: pointer; background: none; border: none; }
table  { border-collapse: collapse; width: 100%; }
a { color: var(--color-primary); text-decoration: none; }
a:hover { color: var(--color-primary-hover); text-decoration: underline; }

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}
::selection {
  background: oklch(from var(--color-primary) l c h / 0.2);
  color: var(--color-text);
}
a, button, input, textarea, select {
  transition: color var(--transition-interactive),
              background var(--transition-interactive),
              border-color var(--transition-interactive),
              box-shadow var(--transition-interactive);
}
.sr-only {
  position:absolute;width:1px;height:1px;padding:0;margin:-1px;
  overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border-width:0;
}

/* --- LAYOUT --- */
.container {
  max-width: var(--content-default);
  margin-inline: auto;
  padding-inline: var(--space-6);
}
.container--wide  { max-width: var(--content-wide); }
.container--narrow{ max-width: var(--content-narrow); }

/* --- NAVBAR --- */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}
.navbar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: var(--space-4);
}
.navbar__logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  text-decoration: none;
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-style: italic;
  font-weight: 600;
  letter-spacing: 0.01em;
}
.navbar__logo:hover { text-decoration: none; color: var(--color-primary); }
.navbar__nav {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  list-style: none;
}
.navbar__nav a {
  display: block;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  text-decoration: none;
  white-space: nowrap;
}
.navbar__nav a:hover {
  color: var(--color-text);
  background: var(--color-surface-offset);
  text-decoration: none;
}
.navbar__nav a.active {
  color: var(--color-primary);
  background: var(--color-primary-highlight);
}
.navbar__actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}
/* Mobile hamburger */
.navbar__toggle {
  display: none;
  padding: var(--space-2);
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
}
.navbar__toggle:hover { background: var(--color-surface-offset); color: var(--color-text); }
@media (max-width: 768px) {
  .navbar__toggle { display: flex; align-items: center; justify-content: center; }
  .navbar__nav {
    display: none;
    position: absolute;
    top: 64px; left: 0; right: 0;
    flex-direction: column;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-3) var(--space-4);
    gap: var(--space-1);
  }
  .navbar__nav.open { display: flex; }
  .navbar__nav a { width: 100%; padding: var(--space-3) var(--space-4); }
}

/* --- FOOTER --- */
.site-footer {
  margin-top: auto;
  background: var(--color-surface-offset);
  border-top: 1px solid var(--color-border);
  padding: var(--space-10) 0 var(--space-6);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
}
.footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: var(--space-8);
  margin-bottom: var(--space-8);
}
.footer__brand-name {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-style: italic;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}
.footer__heading {
  font-weight: 600;
  color: var(--color-text);
  font-size: var(--text-sm);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: var(--space-3);
}
.footer__links { list-style: none; display: flex; flex-direction: column; gap: var(--space-2); }
.footer__links a { color: var(--color-text-muted); }
.footer__links a:hover { color: var(--color-primary); text-decoration: none; }
.footer__bottom {
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-divider);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-3);
}
@media (max-width: 640px) {
  .footer__grid { grid-template-columns: 1fr; gap: var(--space-6); }
  .footer__bottom { flex-direction: column; text-align: center; }
}

/* --- BUTTONS --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-5);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: 600;
  text-decoration: none;
  border: 1px solid transparent;
  white-space: nowrap;
  min-height: 40px;
}
.btn:hover { text-decoration: none; }
.btn-primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
  border-color: var(--color-primary);
}
.btn-primary:hover { background: var(--color-primary-hover); border-color: var(--color-primary-hover); color: var(--color-text-inverse); }
.btn-secondary {
  background: var(--color-surface-offset);
  color: var(--color-text);
  border-color: var(--color-border);
}
.btn-secondary:hover { background: var(--color-surface-dynamic); color: var(--color-text); }
.btn-ghost {
  background: transparent;
  color: var(--color-text-muted);
  border-color: transparent;
}
.btn-ghost:hover { background: var(--color-surface-offset); color: var(--color-text); }
.btn-danger {
  background: var(--color-error);
  color: #fff;
  border-color: var(--color-error);
}
.btn-danger:hover { opacity: .85; }
.btn-sm { min-height: 32px; padding: var(--space-1) var(--space-3); font-size: var(--text-xs); }
.btn-full { width: 100%; }

/* --- FORMS --- */
.form-group { display: flex; flex-direction: column; gap: var(--space-1); margin-bottom: var(--space-4); }
.form-label { font-size: var(--text-sm); font-weight: 500; color: var(--color-text-muted); }
.form-input, .form-select, .form-textarea {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface-2);
  color: var(--color-text);
  font-size: var(--text-base);
  min-height: 44px;
}
.form-input::placeholder { color: var(--color-text-faint); }
.form-input:focus, .form-select:focus, .form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px oklch(from var(--color-primary) l c h / 0.15);
}
.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-4);
}
@media (max-width: 480px) { .form-row { grid-template-columns: 1fr; } }
.form-help { font-size: var(--text-xs); color: var(--color-text-faint); margin-top: var(--space-1); }
.form-error { font-size: var(--text-xs); color: var(--color-error); margin-top: var(--space-1); }

/* --- ALERTS --- */
.alert {
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  margin-bottom: var(--space-4);
  border: 1px solid transparent;
}
.alert-success {
  background: var(--color-success-highlight);
  color: var(--color-success);
  border-color: oklch(from var(--color-success) l c h / 0.3);
}
.alert-error {
  background: var(--color-error-highlight);
  color: var(--color-error);
  border-color: oklch(from var(--color-error) l c h / 0.3);
}
.alert-warning {
  background: var(--color-warning-highlight);
  color: var(--color-warning);
  border-color: oklch(from var(--color-warning) l c h / 0.3);
}

/* --- CARDS --- */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}
.card-body { padding: var(--space-6); }
.card-title {
  font-size: var(--text-lg);
  font-weight: 600;
  margin-bottom: var(--space-1);
}

/* --- TABLES --- */
.table-wrapper { overflow-x: auto; border: 1px solid var(--color-border); border-radius: var(--radius-lg); }
.table th, .table td {
  padding: var(--space-3) var(--space-4);
  text-align: left;
  border-bottom: 1px solid var(--color-divider);
  font-size: var(--text-sm);
  white-space: nowrap;
}
.table th {
  background: var(--color-surface-offset);
  font-weight: 600;
  color: var(--color-text-muted);
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.table tr:last-child td { border-bottom: none; }
.table tbody tr:hover { background: var(--color-surface-offset); }

/* --- BADGES --- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px var(--space-2);
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.badge-admin    { background: var(--color-primary-highlight); color: var(--color-primary-hover); }
.badge-user     { background: var(--color-surface-dynamic);   color: var(--color-text-muted); }
.badge-pending  { background: var(--color-warning-highlight); color: var(--color-warning); }
.badge-success  { background: var(--color-success-highlight); color: var(--color-success); }
.badge-error    { background: var(--color-error-highlight);   color: var(--color-error); }

/* --- ADMIN SIDEBAR LAYOUT --- */
.admin-layout { display: flex; min-height: calc(100vh - 64px); }
.admin-sidebar {
  width: 240px;
  flex-shrink: 0;
  background: var(--color-surface);
  border-right: 1px solid var(--color-border);
  padding: var(--space-6) var(--space-3);
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}
.admin-sidebar__label {
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-faint);
  padding: var(--space-3) var(--space-3) var(--space-1);
  margin-top: var(--space-2);
}
.admin-sidebar a {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  text-decoration: none;
}
.admin-sidebar a:hover { background: var(--color-surface-offset); color: var(--color-text); text-decoration: none; }
.admin-sidebar a.active { background: var(--color-primary-highlight); color: var(--color-primary); }
.admin-content {
  flex: 1;
  padding: var(--space-8);
  overflow: auto;
  min-width: 0;
}
.admin-content__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-6);
  flex-wrap: wrap;
  gap: var(--space-3);
}
.admin-content__title {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-style: italic;
}
@media (max-width: 768px) {
  .admin-layout { flex-direction: column; }
  .admin-sidebar { width: 100%; flex-direction: row; flex-wrap: wrap; padding: var(--space-3); border-right: none; border-bottom: 1px solid var(--color-border); }
  .admin-sidebar__label { display: none; }
  .admin-content { padding: var(--space-4); }
}

/* --- MODAL --- */
.modal-overlay {
  display: none;
  position: fixed; inset: 0;
  background: oklch(0.1 0 0 / 0.5);
  backdrop-filter: blur(4px);
  z-index: 200;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
}
.modal-overlay.open { display: flex; }
.modal {
  background: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 520px;
  max-height: 90vh;
  overflow-y: auto;
}
.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-5) var(--space-6);
  border-bottom: 1px solid var(--color-divider);
}
.modal-title { font-weight: 600; font-size: var(--text-lg); }
.modal-body { padding: var(--space-6); }
.modal-footer {
  padding: var(--space-4) var(--space-6);
  border-top: 1px solid var(--color-divider);
  display: flex;
  gap: var(--space-3);
  justify-content: flex-end;
}

/* --- UTILITIES --- */
.text-muted  { color: var(--color-text-muted); }
.text-faint  { color: var(--color-text-faint); }
.text-sm     { font-size: var(--text-sm); }
.text-xs     { font-size: var(--text-xs); }
.font-bold   { font-weight: 700; }
.mt-0 { margin-top: 0; }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.gap-3 { gap: var(--space-3); }
.flex { display: flex; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.flex-wrap { flex-wrap: wrap; }