/* ============================================================
   PTTrack – SportTech Pro Theme
   Plus Jakarta Sans · Primary #1A56DB · Accent #F97316
   Dark Sidebar #1E2A3B · Mobile-first for in-session logging
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:ital,wght@0,300;0,400;0,500;0,600;0,700;0,800;1,400;1,600&display=swap');

/* ── 1. CSS Custom Properties ───────────────────────────────── */
:root {
  /* Brand palette */
  --color-primary:       #1A56DB;
  --color-primary-dark:  #1242B4;
  --color-primary-light: #3B82F6;
  --color-primary-alpha: rgba(26, 86, 219, 0.12);
  --color-secondary:     #1E2A3B;
  --color-accent:        #F97316;
  --color-accent-dark:   #EA6A0A;
  --color-accent-alpha:  rgba(249, 115, 22, 0.12);

  /* Surfaces & backgrounds */
  --color-bg:          #EFF3F8;
  --color-surface:     #FFFFFF;
  --color-surface-alt: #F1F5F9;
  --color-sidebar:     #1E2A3B;
  --color-sidebar-hover: #283650;
  --color-sidebar-active: rgba(249, 115, 22, 0.15);

  /* Semantic text */
  --color-text:         #0F172A;
  --color-text-muted:   #64748B;
  --color-text-subtle:  #94A3B8;
  --color-text-inverse: #FFFFFF;

  /* Borders & dividers */
  --color-border:       #E2E8F0;
  --color-border-focus: #1A56DB;

  /* Status colours */
  --color-success:       #10B981;
  --color-success-bg:    #ECFDF5;
  --color-success-border:#6EE7B7;
  --color-warning:       #F59E0B;
  --color-warning-bg:    #FFFBEB;
  --color-warning-border:#FCD34D;
  --color-error:         #EF4444;
  --color-error-bg:      #FEF2F2;
  --color-error-border:  #FCA5A5;
  --color-info:          #06B6D4;
  --color-info-bg:       #ECFEFF;
  --color-info-border:   #67E8F9;

  /* Typography */
  --font-body:     'Plus Jakarta Sans', system-ui, -apple-system, sans-serif;
  --font-mono:     ui-monospace, 'Cascadia Code', 'Fira Code', monospace;
  --font-size-xs:  12px;
  --font-size-sm:  13px;
  --font-size-base:15px;
  --font-size-md:  16px;
  --font-size-lg:  18px;
  --font-size-xl:  20px;
  --font-size-2xl: 24px;
  --font-size-3xl: 30px;
  --font-size-4xl: 36px;
  --font-weight-normal:   400;
  --font-weight-medium:   500;
  --font-weight-semibold: 600;
  --font-weight-bold:     700;
  --font-weight-extrabold:800;
  --line-height-tight: 1.25;
  --line-height-snug:  1.375;
  --line-height-base:  1.6;
  --line-height-loose: 1.75;

  /* Spacing scale */
  --space-1: 4px;   --space-2: 8px;   --space-3: 12px;
  --space-4: 16px;  --space-5: 20px;  --space-6: 24px;
  --space-8: 32px;  --space-10: 40px; --space-12: 48px;
  --space-16: 64px;

  /* Radii */
  --radius-sm:  6px;
  --radius-md:  10px;
  --radius-lg:  14px;
  --radius-xl:  18px;
  --radius-2xl: 24px;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-xs:  0 1px 2px rgba(15,23,42,0.06);
  --shadow-sm:  0 1px 3px rgba(15,23,42,0.08), 0 1px 2px rgba(15,23,42,0.05);
  --shadow-md:  0 4px 12px rgba(15,23,42,0.10), 0 2px 4px rgba(15,23,42,0.06);
  --shadow-lg:  0 10px 24px rgba(15,23,42,0.12), 0 4px 8px rgba(15,23,42,0.06);
  --shadow-xl:  0 20px 48px rgba(15,23,42,0.14), 0 8px 16px rgba(15,23,42,0.08);
  --shadow-primary: 0 4px 14px rgba(26, 86, 219, 0.30);
  --shadow-accent:  0 4px 14px rgba(249, 115, 22, 0.30);

  /* Layout */
  --sidebar-width:       256px;
  --sidebar-collapsed:   68px;
  --topbar-height:       64px;
  --content-max-width:   1280px;
  --content-padding:     var(--space-6);

  /* Transitions */
  --transition-fast:   150ms ease;
  --transition-base:   220ms ease;
  --transition-slow:   350ms ease;
  --transition-spring: 220ms cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ── 2. Reset & Base ────────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: var(--font-size-base);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  line-height: var(--line-height-base);
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

img, video, svg { display: block; max-width: 100%; }
a { color: var(--color-primary); text-decoration: none; transition: color var(--transition-fast); }
a:hover { color: var(--color-primary-dark); }
ul, ol { list-style: none; }
button, input, select, textarea { font-family: inherit; font-size: inherit; }
button { cursor: pointer; border: none; background: none; }
h1,h2,h3,h4,h5,h6 {
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-text);
}
p { margin-bottom: var(--space-4); }
p:last-child { margin-bottom: 0; }
hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-6) 0;
}
code, pre, kbd {
  font-family: var(--font-mono);
  font-size: 0.875em;
}
pre {
  background: var(--color-surface-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  overflow-x: auto;
}
strong { font-weight: var(--font-weight-semibold); }

/* ── 3. Layout Shell ────────────────────────────────────────── */
.app-wrapper {
  display: flex;
  min-height: 100vh;
}

/* ── 4. Sidebar Navigation ──────────────────────────────────── */
.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  height: 100vh;
  width: var(--sidebar-width);
  background: var(--color-sidebar);
  color: var(--color-text-inverse);
  display: flex;
  flex-direction: column;
  z-index: 100;
  overflow-y: auto;
  overflow-x: hidden;
  transition: width var(--transition-base), transform var(--transition-base);
  box-shadow: 4px 0 24px rgba(15,23,42,0.18);
}

/* Sidebar brand / logo */
.sidebar-brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-5) var(--space-5);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  min-height: var(--topbar-height);
  text-decoration: none;
  flex-shrink: 0;
}
.sidebar-brand-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 18px;
  font-weight: var(--font-weight-extrabold);
  color: #fff;
  box-shadow: var(--shadow-primary);
}
.sidebar-brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}
.sidebar-brand-name {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-extrabold);
  color: #fff;
  letter-spacing: -0.02em;
}
.sidebar-brand-sub {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-medium);
  color: rgba(255,255,255,0.45);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* Sidebar sections */
.sidebar-section {
  padding: var(--space-5) 0 var(--space-2);
  flex-shrink: 0;
}
.sidebar-section + .sidebar-section {
  border-top: 1px solid rgba(255,255,255,0.06);
}
.sidebar-section-label {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: rgba(255,255,255,0.30);
  padding: 0 var(--space-5) var(--space-2);
}

/* Nav links */
.nav-link,
.sidebar-link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-2) var(--space-5);
  color: rgba(255,255,255,0.68);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  border-radius: 0;
  transition: color var(--transition-fast), background var(--transition-fast);
  position: relative;
  text-decoration: none;
  line-height: 1.4;
  min-height: 40px;
}
.nav-link:hover,
.sidebar-link:hover {
  color: #fff;
  background: var(--color-sidebar-hover);
}
.nav-link.active,
.sidebar-link.active,
.nav-link.active-link {
  color: #fff;
  background: var(--color-sidebar-active);
  font-weight: var(--font-weight-semibold);
}
.nav-link.active::before,
.sidebar-link.active::before,
.nav-link.active-link::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 3px;
  height: 60%;
  background: var(--color-accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}
.nav-link-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  opacity: 0.75;
}
.nav-link.active .nav-link-icon,
.sidebar-link.active .nav-link-icon {
  opacity: 1;
}

/* Sidebar footer (user info) */
.sidebar-footer {
  margin-top: auto;
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: var(--space-4) var(--space-5);
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-shrink: 0;
}
.sidebar-user-avatar {
  width: 34px;
  height: 34px;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-bold);
  color: #fff;
  flex-shrink: 0;
}
.sidebar-user-info { min-width: 0; }
.sidebar-user-name {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: #fff;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.sidebar-user-role {
  font-size: var(--font-size-xs);
  color: rgba(255,255,255,0.40);
  text-transform: capitalize;
}

/* ── 5. Main Content Area ───────────────────────────────────── */
.main-content {
  margin-left: var(--sidebar-width);
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.content-body {
  flex: 1;
  padding: var(--content-padding);
}

/* ── 6. Top Bar (within main, role pill + breadcrumb) ───────── */
.topbar {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  height: var(--topbar-height);
  display: flex;
  align-items: center;
  padding: 0 var(--content-padding);
  gap: var(--space-4);
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: var(--shadow-xs);
}
.topbar-breadcrumb {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}
.topbar-breadcrumb a { color: var(--color-text-muted); }
.topbar-breadcrumb a:hover { color: var(--color-primary); }
.topbar-breadcrumb .sep { color: var(--color-border); }
.topbar-actions { margin-left: auto; display: flex; align-items: center; gap: var(--space-3); }

/* ── 7. Container ───────────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 0 var(--content-padding);
}
.container-sm  { max-width: 640px;  margin: 0 auto; }
.container-md  { max-width: 860px;  margin: 0 auto; }
.container-lg  { max-width: 1100px; margin: 0 auto; }

/* ── 8. Page Header ─────────────────────────────────────────── */
.page-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
  margin-bottom: var(--space-8);
}
.page-header-left {}
.page-title {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-extrabold);
  color: var(--color-text);
  letter-spacing: -0.03em;
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-1);
}
.page-subtitle {
  font-size: var(--font-size-base);
  color: var(--color-text-muted);
  font-weight: var(--font-weight-normal);
  line-height: var(--line-height-snug);
}
.page-header-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
}

/* Section headings */
h2.section-title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  letter-spacing: -0.02em;
  margin-bottom: var(--space-5);
}
h3.section-title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--space-4);
}

/* ── 9. Cards ───────────────────────────────────────────────── */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  padding: var(--space-6);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}
.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}
.card-flat {
  box-shadow: none;
}
.card-flat:hover {
  box-shadow: var(--shadow-sm);
}
.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-5);
  padding-bottom: var(--space-4);
  border-bottom: 1px solid var(--color-border);
}
.card-title {
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  letter-spacing: -0.01em;
}
.card-subtitle {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-top: 2px;
}
.card-body {}
.card-footer {
  margin-top: var(--space-5);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* Stat card (dashboard KPIs) */
.stat-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  padding: var(--space-6);
  display: flex;
  align-items: flex-start;
  gap: var(--space-4);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}
.stat-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}
.stat-card-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  flex-shrink: 0;
}
.stat-card-icon.primary  { background: var(--color-primary-alpha); color: var(--color-primary); }
.stat-card-icon.accent   { background: var(--color-accent-alpha);  color: var(--color-accent); }
.stat-card-icon.success  { background: #ECFDF5; color: var(--color-success); }
.stat-card-icon.warning  { background: #FFFBEB; color: var(--color-warning); }
.stat-card-icon.error    { background: #FEF2F2; color: var(--color-error); }
.stat-card-data {}
.stat-card-value {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-extrabold);
  letter-spacing: -0.04em;
  line-height: 1;
  color: var(--color-text);
}
.stat-card-label {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  font-weight: var(--font-weight-medium);
  margin-top: var(--space-1);
}
.stat-card-delta {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  margin-top: var(--space-2);
  display: inline-flex;
  align-items: center;
  gap: 3px;
  padding: 2px 8px;
  border-radius: var(--radius-full);
}
.stat-card-delta.up   { background: #ECFDF5; color: #065F46; }
.stat-card-delta.down { background: #FEF2F2; color: #991B1B; }

/* ── 10. Buttons ────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 9px var(--space-5);
  font-family: var(--font-body);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  line-height: 1.4;
  border-radius: var(--radius-lg);
  border: 2px solid transparent;
  cursor: pointer;
  transition: background var(--transition-fast), box-shadow var(--transition-fast),
              transform var(--transition-spring), border-color var(--transition-fast),
              color var(--transition-fast), opacity var(--transition-fast);
  white-space: nowrap;
  user-select: none;
  text-decoration: none;
}
.btn:active { transform: scale(0.97); }
.btn:disabled,
.btn.disabled {
  opacity: 0.5;
  pointer-events: none;
}
.btn svg, .btn i { flex-shrink: 0; }

/* Primary */
.btn-primary {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  color: #fff;
  box-shadow: var(--shadow-primary);
  border-color: transparent;
}
.btn-primary:hover {
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, #0E358F 100%);
  box-shadow: 0 6px 20px rgba(26,86,219,0.40);
  color: #fff;
}
.btn-primary:active { box-shadow: none; }

/* Accent / CTA */
.btn-accent {
  background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-dark) 100%);
  color: #fff;
  box-shadow: var(--shadow-accent);
  border-color: transparent;
}
.btn-accent:hover {
  background: linear-gradient(135deg, var(--color-accent-dark) 0%, #D05A04 100%);
  box-shadow: 0 6px 20px rgba(249,115,22,0.40);
  color: #fff;
}
.btn-accent:active { box-shadow: none; }

/* Secondary (outlined) */
.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
  box-shadow: var(--shadow-xs);
}
.btn-secondary:hover {
  background: var(--color-surface-alt);
  border-color: var(--color-text-subtle);
  color: var(--color-text);
}

/* Outlined primary */
.btn-outline {
  background: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}
.btn-outline:hover {
  background: var(--color-primary-alpha);
  color: var(--color-primary-dark);
}

/* Ghost */
.btn-ghost {
  background: transparent;
  color: var(--color-text-muted);
  border-color: transparent;
}
.btn-ghost:hover {
  background: var(--color-surface-alt);
  color: var(--color-text);
}

/* Danger */
.btn-danger {
  background: var(--color-error);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 4px 14px rgba(239,68,68,0.28);
}
.btn-danger:hover {
  background: #DC2626;
  box-shadow: 0 6px 20px rgba(239,68,68,0.38);
  color: #fff;
}

/* Success */
.btn-success {
  background: var(--color-success);
  color: #fff;
  border-color: transparent;
  box-shadow: 0 4px 14px rgba(16,185,129,0.28);
}
.btn-success:hover {
  background: #059669;
  box-shadow: 0 6px 20px rgba(16,185,129,0.38);
  color: #fff;
}

/* Sizes */
.btn-sm {
  padding: 6px var(--space-4);
  font-size: var(--font-size-xs);
  border-radius: var(--radius-md);
}
.btn-lg {
  padding: 13px var(--space-8);
  font-size: var(--font-size-md);
  border-radius: var(--radius-xl);
}
.btn-xl {
  padding: 18px var(--space-10);
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-extrabold);
  border-radius: var(--radius-2xl);
  letter-spacing: -0.01em;
}
.btn-block { width: 100%; }
.btn-icon {
  width: 38px;
  height: 38px;
  padding: 0;
  border-radius: var(--radius-md);
}
.btn-icon.btn-sm { width: 30px; height: 30px; }
.btn-icon.btn-lg { width: 46px; height: 46px; border-radius: var(--radius-lg); }

/* ── 11. Forms ──────────────────────────────────────────────── */
.form-group {
  margin-bottom: var(--space-5);
}
.form-label {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text);
  margin-bottom: var(--space-2);
  letter-spacing: -0.01em;
}
.form-label .required {
  color: var(--color-error);
  margin-left: 2px;
}
.form-hint {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  margin-top: var(--space-1);
  line-height: 1.4;
}
.form-error {
  font-size: var(--font-size-xs);
  color: var(--color-error);
  margin-top: var(--space-1);
  display: flex;
  align-items: center;
  gap: 4px;
  font-weight: var(--font-weight-medium);
}

/* Base input styles */
.form-input,
.form-textarea,
.form-select {
  display: block;
  width: 100%;
  padding: 10px var(--space-4);
  font-family: var(--font-body);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  color: var(--color-text);
  background: var(--color-surface);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-lg);
  line-height: 1.5;
  appearance: none;
  -webkit-appearance: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast),
              background var(--transition-fast);
  outline: none;
}
.form-input::placeholder,
.form-textarea::placeholder {
  color: var(--color-text-subtle);
}
.form-input:hover,
.form-textarea:hover,
.form-select:hover {
  border-color: var(--color-text-subtle);
}
.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  border-color: var(--color-border-focus);
  box-shadow: 0 0 0 3px var(--color-primary-alpha);
  background: var(--color-surface);
}
.form-input.is-invalid,
.form-textarea.is-invalid,
.form-select.is-invalid {
  border-color: var(--color-error);
}
.form-input.is-invalid:focus,
.form-textarea.is-invalid:focus,
.form-select.is-invalid:focus {
  box-shadow: 0 0 0 3px rgba(239,68,68,0.15);
}
.form-textarea {
  min-height: 100px;
  resize: vertical;
}
.form-select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2364748B' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  padding-right: 42px;
  cursor: pointer;
}

/* Input group (icon inside input) */
.input-group {
  position: relative;
}
.input-group .form-input {
  padding-left: 42px;
}
.input-group-icon {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-muted);
  pointer-events: none;
  width: 18px;
  height: 18px;
}

/* Large workout-session inputs (mobile usability) */
.form-input-workout {
  padding: 14px var(--space-4);
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-bold);
  text-align: center;
  border-width: 2px;
  border-radius: var(--radius-xl);
  letter-spacing: -0.02em;
}
.form-input-workout:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 4px var(--color-primary-alpha);
}

/* Checkbox & Radio */
.form-check {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  cursor: pointer;
}
.form-check-input {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  margin-top: 2px;
  appearance: none;
  -webkit-appearance: none;
  border: 2px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  cursor: pointer;
  transition: border-color var(--transition-fast), background var(--transition-fast);
  position: relative;
}
.form-check-input[type="radio"] { border-radius: 50%; }
.form-check-input:checked {
  background: var(--color-primary);
  border-color: var(--color-primary);
}
.form-check-input:checked::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -60%) rotate(45deg);
  width: 5px;
  height: 9px;
  border: 2px solid #fff;
  border-top: none;
  border-left: none;
}
.form-check-input[type="radio"]:checked::after {
  transform: translate(-50%, -50%) rotate(0);
  width: 7px;
  height: 7px;
  background: #fff;
  border: none;
  border-radius: 50%;
}
.form-check-label {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text);
  cursor: pointer;
  line-height: 1.5;
}

/* Toggle switch */
.form-toggle {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  cursor: pointer;
}
.form-toggle-track {
  width: 44px;
  height: 24px;
  background: var(--color-border);
  border-radius: var(--radius-full);
  position: relative;
  transition: background var(--transition-fast);
  flex-shrink: 0;
}
.form-toggle input:checked ~ .form-toggle-track,
.form-toggle-track.checked {
  background: var(--color-primary);
}
.form-toggle-thumb {
  position: absolute;
  top: 3px;
  left: 3px;
  width: 18px;
  height: 18px;
  background: #fff;
  border-radius: var(--radius-full);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-spring);
}
.form-toggle input:checked ~ .form-toggle-track .form-toggle-thumb,
.form-toggle-track.checked .form-toggle-thumb {
  transform: translateX(20px);
}
.form-toggle input { display: none; }

/* Inline form row */
.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: var(--space-4);
}

/* ── 12. Alerts & Flash Messages ────────────────────────────── */
.alert {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-5);
  border-radius: var(--radius-lg);
  border-left: 4px solid transparent;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  line-height: 1.5;
  margin-bottom: var(--space-5);
}
.alert-icon { flex-shrink: 0; width: 20px; height: 20px; margin-top: 1px; }
.alert-content {}
.alert-title {
  font-weight: var(--font-weight-bold);
  margin-bottom: 2px;
}
.alert-success {
  background: var(--color-success-bg);
  border-left-color: var(--color-success);
  color: #065F46;
}
.alert-warning {
  background: var(--color-warning-bg);
  border-left-color: var(--color-warning);
  color: #92400E;
}
.alert-error,
.alert-danger {
  background: var(--color-error-bg);
  border-left-color: var(--color-error);
  color: #991B1B;
}
.alert-info {
  background: var(--color-info-bg);
  border-left-color: var(--color-info);
  color: #0E7490;
}

/* Injury warning banner (prominent, mid-workout) */
.injury-warning {
  display: flex;
  align-items: flex-start;
  gap: var(--space-4);
  padding: var(--space-5) var(--space-6);
  background: #FFFBEB;
  border: 2px solid var(--color-warning);
  border-radius: var(--radius-xl);
  margin-bottom: var(--space-6);
  box-shadow: 0 4px 16px rgba(245,158,11,0.18);
}
.injury-warning-icon {
  width: 32px;
  height: 32px;
  background: var(--color-warning);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 18px;
  flex-shrink: 0;
}
.injury-warning-title {
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-bold);
  color: #78350F;
  margin-bottom: var(--space-1);
}
.injury-warning-text {
  font-size: var(--font-size-sm);
  color: #92400E;
  line-height: 1.5;
}
.injury-warning-list {
  margin-top: var(--space-2);
  padding-left: var(--space-4);
  list-style: disc;
}
.injury-warning-list li {
  font-size: var(--font-size-sm);
  color: #92400E;
  margin-bottom: 2px;
}

/* ── 13. Badges ─────────────────────────────────────────────── */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 3px 10px;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
  line-height: 1.4;
  border-radius: var(--radius-full);
  white-space: nowrap;
  letter-spacing: 0.01em;
}
.badge-primary  { background: var(--color-primary-alpha); color: var(--color-primary-dark); }
.badge-accent   { background: var(--color-accent-alpha);  color: #C2410C; }
.badge-success  { background: #D1FAE5; color: #065F46; }
.badge-warning  { background: #FEF3C7; color: #92400E; }
.badge-danger   { background: #FEE2E2; color: #991B1B; }
.badge-info     { background: #CFFAFE; color: #0E7490; }
.badge-neutral  { background: var(--color-surface-alt); color: var(--color-text-muted); border: 1px solid var(--color-border); }
.badge-dark     { background: var(--color-secondary); color: #fff; }

/* At-risk client badge (gym owner dashboard) */
.badge-at-risk {
  background: #FEE2E2;
  color: #991B1B;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
  padding: 3px 10px;
  border-radius: var(--radius-full);
  border: 1px solid #FCA5A5;
  animation: pulse-risk 2s ease-in-out infinite;
}
@keyframes pulse-risk {
  0%, 100% { box-shadow: 0 0 0 0 rgba(239,68,68,0); }
  50%       { box-shadow: 0 0 0 4px rgba(239,68,68,0.15); }
}

/* Role badges */
.badge-role-platform_admin { background: #EDE9FE; color: #6D28D9; }
.badge-role-gym_owner      { background: var(--color-primary-alpha); color: var(--color-primary-dark); }
.badge-role-instructor     { background: var(--color-accent-alpha); color: #C2410C; }
.badge-role-client         { background: var(--color-surface-alt); color: var(--color-text-muted); border: 1px solid var(--color-border); }

/* ── 14. Tables ─────────────────────────────────────────────── */
.table-wrapper {
  overflow-x: auto;
  border-radius: var(--radius-xl);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}
.table {
  width: 100%;
  border-collapse: collapse;
  background: var(--color-surface);
  font-size: var(--font-size-sm);
}
.table thead {
  background: var(--color-secondary);
}
.table thead th {
  padding: var(--space-4) var(--space-5);
  text-align: left;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  background-color: var(--color-secondary) !important;
  color: #ffffff !important;
  white-space: nowrap;
  border-bottom: none;
}
.table thead th:first-child { border-radius: var(--radius-xl) 0 0 0; }
.table thead th:last-child  { border-radius: 0 var(--radius-xl) 0 0; }
.table tbody tr {
  border-bottom: 1px solid var(--color-border);
  transition: background var(--transition-fast);
}
.table tbody tr:last-child { border-bottom: none; }
.table tbody tr:hover { background: var(--color-surface-alt); }
.table tbody tr:nth-child(even) { background: rgba(241,245,249,0.50); }
.table tbody tr:nth-child(even):hover { background: var(--color-surface-alt); }
.table td {
  padding: var(--space-4) var(--space-5);
  color: var(--color-text);
  vertical-align: middle;
}
.table-sm thead th { padding: var(--space-3) var(--space-4); }
.table-sm td       { padding: var(--space-3) var(--space-4); }
.table tfoot tr { background: var(--color-surface-alt); }
.table tfoot td {
  padding: var(--space-3) var(--space-5);
  font-weight: var(--font-weight-semibold);
  border-top: 2px solid var(--color-border);
}

/* ── 15. Session Logging UI ─────────────────────────────────── */
/* Large tap targets for mid-workout use on mobile */
.session-header {
  background: linear-gradient(135deg, var(--color-secondary) 0%, #2D3F56 100%);
  color: #fff;
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  margin-bottom: var(--space-6);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
}
.session-title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-extrabold);
  letter-spacing: -0.02em;
}
.session-meta {
  font-size: var(--font-size-sm);
  color: rgba(255,255,255,0.60);
  margin-top: 4px;
}
.session-timer {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-extrabold);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.03em;
  color: var(--color-accent);
}

/* Exercise card in session */
.exercise-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  overflow: hidden;
  margin-bottom: var(--space-5);
  box-shadow: var(--shadow-sm);
}
.exercise-card-header {
  background: var(--color-primary-alpha);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-4) var(--space-5);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.exercise-card-name {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-primary-dark);
  letter-spacing: -0.01em;
}
.exercise-card-body { padding: var(--space-5); }

/* Set logging row */
.set-row {
  display: grid;
  grid-template-columns: 40px 1fr 1fr auto;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--color-border);
}
.set-row:last-child { border-bottom: none; }
.set-number {
  width: 36px;
  height: 36px;
  background: var(--color-secondary);
  color: #fff;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-bold);
  flex-shrink: 0;
}
.set-number.completed { background: var(--color-success); }
.set-prev-data {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  margin-top: 2px;
}

/* Duo session – two client panels side-by-side */
.duo-session-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-5);
  margin-bottom: var(--space-6);
}
.duo-client-panel {
  border: 2px solid var(--color-border);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}
.duo-client-panel.active {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 4px var(--color-primary-alpha), var(--shadow-md);
}
.duo-client-header {
  padding: var(--space-4) var(--space-5);
  background: var(--color-surface-alt);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  gap: var(--space-3);
}
.duo-client-panel.active .duo-client-header {
  background: var(--color-primary);
  border-bottom-color: var(--color-primary-dark);
}
.duo-client-name {
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
}
.duo-client-panel.active .duo-client-name { color: #fff; }
.duo-client-body { padding: var(--space-5); }
.duo-turn-indicator {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  background: rgba(255,255,255,0.25);
  color: #fff;
}

/* Progress / prev-set ghost data */
.prev-session-ghost {
  font-size: var(--font-size-xs);
  color: var(--color-text-subtle);
  font-style: italic;
  margin-bottom: var(--space-3);
  padding: var(--space-2) var(--space-3);
  background: var(--color-surface-alt);
  border-radius: var(--radius-md);
}

/* Machine settings grid */
.machine-settings-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: var(--space-3);
  margin-top: var(--space-3);
}
.machine-setting-item label {
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-bold);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  margin-bottom: 4px;
  display: block;
}

/* ── 16. Charts (Chart.js canvas) ───────────────────────────── */
.chart-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  padding: var(--space-6);
}
.chart-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-5);
}
.chart-card-title {
  font-size: var(--font-size-md);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
}
.chart-period-select {
  display: flex;
  gap: var(--space-1);
}
.chart-period-btn {
  padding: 5px 12px;
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-md);
  border: 1.5px solid var(--color-border);
  background: transparent;
  color: var(--color-text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
}
.chart-period-btn.active,
.chart-period-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: var(--color-primary-alpha);
}
.chart-canvas-wrap {
  position: relative;
  height: 260px;
}

/* ── 17. Progress indicators ────────────────────────────────── */
.progress-bar-wrap {
  height: 8px;
  background: var(--color-border);
  border-radius: var(--radius-full);
  overflow: hidden;
}
.progress-bar {
  height: 100%;
  border-radius: var(--radius-full);
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-light));
  transition: width var(--transition-slow);
}
.progress-bar.accent { background: linear-gradient(90deg, var(--color-accent), #FB923C); }
.progress-bar.success { background: var(--color-success); }

/* ── 18. Empty state ────────────────────────────────────────── */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--space-16) var(--space-8);
}
.empty-state-icon {
  width: 72px;
  height: 72px;
  background: var(--color-surface-alt);
  border-radius: var(--radius-2xl);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
  margin-bottom: var(--space-5);
  border: 1px solid var(--color-border);
}
.empty-state-title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  margin-bottom: var(--space-2);
}
.empty-state-text {
  font-size: var(--font-size-base);
  color: var(--color-text-muted);
  max-width: 360px;
  margin: 0 auto var(--space-6);
}

/* ── 19. Avatar & User tiles ────────────────────────────────── */
.avatar {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  font-weight: var(--font-weight-bold);
  flex-shrink: 0;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  color: #fff;
}
.avatar-sm  { width: 28px; height: 28px; font-size: var(--font-size-xs); }
.avatar-md  { width: 38px; height: 38px; font-size: var(--font-size-sm); }
.avatar-lg  { width: 52px; height: 52px; font-size: var(--font-size-md); }
.avatar-xl  { width: 72px; height: 72px; font-size: var(--font-size-xl); }

.user-tile {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}
.user-tile-name {
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text);
}
.user-tile-meta {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

/* ── 20. Login Page ─────────────────────────────────────────── */
.login-page {
  min-height: 100vh;
  display: flex;
  align-items: stretch;
  background: var(--color-secondary);
}
.login-sidebar {
  width: 480px;
  flex-shrink: 0;
  background: linear-gradient(160deg, #1E2A3B 0%, #0F1823 60%, #162032 100%);
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: var(--space-16) var(--space-12);
  position: relative;
  overflow: hidden;
}
.login-sidebar::before {
  content: '';
  position: absolute;
  top: -120px;
  right: -120px;
  width: 350px;
  height: 350px;
  background: radial-gradient(circle, rgba(26,86,219,0.18) 0%, transparent 70%);
  border-radius: 50%;
}
.login-sidebar::after {
  content: '';
  position: absolute;
  bottom: -80px;
  left: -80px;
  width: 280px;
  height: 280px;
  background: radial-gradient(circle, rgba(249,115,22,0.12) 0%, transparent 70%);
  border-radius: 50%;
}
.login-brand {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-bottom: var(--space-12);
}
.login-brand-icon {
  width: 52px;
  height: 52px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  font-weight: var(--font-weight-extrabold);
  color: #fff;
  box-shadow: var(--shadow-primary);
}
.login-brand-name {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-extrabold);
  color: #fff;
  letter-spacing: -0.04em;
}
.login-hero-title {
  font-size: var(--font-size-4xl);
  font-weight: var(--font-weight-extrabold);
  color: #fff;
  letter-spacing: -0.04em;
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-5);
}
.login-hero-title span { color: var(--color-accent); }
.login-hero-text {
  font-size: var(--font-size-base);
  color: rgba(255,255,255,0.55);
  line-height: var(--line-height-loose);
}
.login-main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-10);
  background: var(--color-bg);
}
.login-card {
  width: 100%;
  max-width: 420px;
  background: var(--color-surface);
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-xl);
  padding: var(--space-10) var(--space-8);
}
.login-title {
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-extrabold);
  color: var(--color-text);
  letter-spacing: -0.03em;
  margin-bottom: var(--space-2);
}
.login-subtitle {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-8);
}

/* ── 21. Dropdown / Context menu ────────────────────────────── */
.dropdown { position: relative; display: inline-block; }
.dropdown-menu {
  position: absolute;
  top: calc(100% + 6px);
  right: 0;
  min-width: 200px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  z-index: 200;
  padding: var(--space-2) 0;
  animation: dropdown-in 0.15s ease;
}
@keyframes dropdown-in {
  from { opacity: 0; transform: translateY(-4px); }
  to   { opacity: 1; transform: translateY(0); }
}
.dropdown-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-2) var(--space-4);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text);
  cursor: pointer;
  transition: background var(--transition-fast), color var(--transition-fast);
  text-decoration: none;
}
.dropdown-item:hover { background: var(--color-surface-alt); color: var(--color-text); }
.dropdown-item.danger { color: var(--color-error); }
.dropdown-item.danger:hover { background: var(--color-error-bg); }
.dropdown-divider { border-top: 1px solid var(--color-border); margin: var(--space-2) 0; }

/* ── 22. Tabs ───────────────────────────────────────────────── */
.tabs {
  display: flex;
  gap: 2px;
  border-bottom: 2px solid var(--color-border);
  margin-bottom: var(--space-6);
}
.tab-item {
  padding: var(--space-3) var(--space-5);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-muted);
  cursor: pointer;
  position: relative;
  text-decoration: none;
  transition: color var(--transition-fast);
  white-space: nowrap;
  border-radius: var(--radius-md) var(--radius-md) 0 0;
}
.tab-item:hover { color: var(--color-text); background: var(--color-surface-alt); }
.tab-item.active {
  color: var(--color-primary);
  font-weight: var(--font-weight-bold);
}
.tab-item.active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--color-primary);
  border-radius: 2px 2px 0 0;
}

/* ── 23. Breadcrumb ─────────────────────────────────────────── */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-5);
  flex-wrap: wrap;
}
.breadcrumb a { color: var(--color-text-muted); }
.breadcrumb a:hover { color: var(--color-primary); }
.breadcrumb-sep { color: var(--color-border); font-size: 1.1em; }
.breadcrumb-current { color: var(--color-text); font-weight: var(--font-weight-medium); }

/* ── 24. Pagination ─────────────────────────────────────────── */
.pagination {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  flex-wrap: wrap;
}
.page-item {
  display: inline-flex;
}
.page-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-muted);
  border: 1.5px solid var(--color-border);
  background: var(--color-surface);
  text-decoration: none;
  transition: all var(--transition-fast);
}
.page-link:hover { border-color: var(--color-primary); color: var(--color-primary); }
.page-item.active .page-link {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}
.page-item.disabled .page-link {
  opacity: 0.4;
  pointer-events: none;
}

/* ── 25. Search bar ─────────────────────────────────────────── */
.search-bar {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: 10px var(--space-4);
  background: var(--color-surface);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-lg);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  max-width: 340px;
}
.search-bar:focus-within {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-alpha);
}
.search-bar input {
  border: none;
  outline: none;
  background: transparent;
  font-size: var(--font-size-sm);
  color: var(--color-text);
  flex: 1;
  min-width: 0;
}
.search-bar input::placeholder { color: var(--color-text-subtle); }
.search-icon { color: var(--color-text-muted); flex-shrink: 0; }

/* ── 26. Flash (Bootstrap alert with custom style) ──────────── */
.flash-container { margin-bottom: var(--space-5); }
.flash-message {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-5);
  border-radius: var(--radius-lg);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  margin-bottom: var(--space-3);
  animation: flash-in 0.3s ease;
}
@keyframes flash-in {
  from { opacity: 0; transform: translateY(-6px); }
  to   { opacity: 1; transform: translateY(0); }
}
.flash-message.success { background: var(--color-success-bg); color: #065F46; border-left: 4px solid var(--color-success); }
.flash-message.error,
.flash-message.danger   { background: var(--color-error-bg);   color: #991B1B; border-left: 4px solid var(--color-error); }
.flash-message.warning  { background: var(--color-warning-bg); color: #92400E; border-left: 4px solid var(--color-warning); }
.flash-message.info     { background: var(--color-info-bg);    color: #0E7490; border-left: 4px solid var(--color-info); }

/* ── 27. Misc Utilities ─────────────────────────────────────── */
.text-primary      { color: var(--color-primary); }
.text-accent       { color: var(--color-accent); }
.text-success      { color: var(--color-success); }
.text-warning      { color: var(--color-warning); }
.text-danger       { color: var(--color-error); }
.text-muted        { color: var(--color-text-muted); }
.text-sm           { font-size: var(--font-size-sm); }
.text-xs           { font-size: var(--font-size-xs); }
.text-lg           { font-size: var(--font-size-lg); }
.text-xl           { font-size: var(--font-size-xl); }
.text-bold         { font-weight: var(--font-weight-bold); }
.text-semibold     { font-weight: var(--font-weight-semibold); }
.text-center       { text-align: center; }
.text-right        { text-align: right; }
.fw-extrabold      { font-weight: var(--font-weight-extrabold); }
.d-flex            { display: flex; }
.align-center      { align-items: center; }
.justify-between   { justify-content: space-between; }
.gap-1             { gap: var(--space-1); }
.gap-2             { gap: var(--space-2); }
.gap-3             { gap: var(--space-3); }
.gap-4             { gap: var(--space-4); }
.gap-5             { gap: var(--space-5); }
.gap-6             { gap: var(--space-6); }
.mt-auto           { margin-top: auto; }
.mb-0              { margin-bottom: 0; }
.mb-4              { margin-bottom: var(--space-4); }
.mb-6              { margin-bottom: var(--space-6); }
.mb-8              { margin-bottom: var(--space-8); }
.w-full            { width: 100%; }
.truncate          { overflow: hidden; white-space: nowrap; text-overflow: ellipsis; }
.divider           { border-top: 1px solid var(--color-border); margin: var(--space-6) 0; }
.rounded-full      { border-radius: var(--radius-full); }
.visually-hidden   { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); border: 0; }

/* Grid helpers */
.grid          { display: grid; }
.grid-2        { grid-template-columns: repeat(2, 1fr); gap: var(--space-5); }
.grid-3        { grid-template-columns: repeat(3, 1fr); gap: var(--space-5); }
.grid-4        { grid-template-columns: repeat(4, 1fr); gap: var(--space-5); }
.grid-auto     { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: var(--space-5); }

/* ── 28. Mobile Toggle (hamburger) ─────────────────────────── */
.sidebar-toggle {
  display: none;
  width: 42px;
  height: 42px;
  align-items: center;
  justify-content: center;
  background: var(--color-surface);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  color: var(--color-text-muted);
  transition: background var(--transition-fast);
  flex-shrink: 0;
}
.sidebar-toggle:hover { background: var(--color-surface-alt); color: var(--color-text); }

/* Sidebar mobile overlay */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(15,23,42,0.50);
  z-index: 99;
  backdrop-filter: blur(2px);
}
.sidebar-overlay.visible { display: block; }

/* ── 29. Responsive ─────────────────────────────────────────── */
@media (max-width: 1024px) {
  :root { --sidebar-width: 220px; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  :root {
    --content-padding: var(--space-4);
    --font-size-base:  14px;
  }

  /* Sidebar becomes off-canvas on mobile */
  .sidebar {
    transform: translateX(-100%);
    width: var(--sidebar-width);
  }
  .sidebar.open { transform: translateX(0); }
  .main-content { margin-left: 0; }

  /* Show hamburger */
  .sidebar-toggle { display: flex; }

  /* Stack page header */
  .page-header { flex-direction: column; align-items: flex-start; }
  .page-title  { font-size: var(--font-size-2xl); }

  /* Full-width cards */
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .duo-session-grid { grid-template-columns: 1fr; }

  /* Table scrollable on mobile */
  .table-wrapper { -webkit-overflow-scrolling: touch; }

  /* Login page stacks on mobile */
  .login-page     { flex-direction: column; }
  .login-sidebar  { width: 100%; padding: var(--space-8) var(--space-6); }
  .login-hero-title { font-size: var(--font-size-3xl); }
  .login-main { padding: var(--space-6); }
  .login-card { padding: var(--space-6); }

  /* Larger session inputs on mobile */
  .form-input-workout { font-size: var(--font-size-3xl); padding: 18px var(--space-4); }
  .set-row { grid-template-columns: 36px 1fr 1fr; }
  .btn-xl { padding: 16px var(--space-6); font-size: var(--font-size-lg); }
}

@media (max-width: 480px) {
  .page-title { font-size: var(--font-size-xl); }
  .stat-card  { flex-direction: column; align-items: flex-start; }
  .tabs       { overflow-x: auto; flex-wrap: nowrap; padding-bottom: 2px; }
  .tab-item   { flex-shrink: 0; }
  .form-row   { grid-template-columns: 1fr; }
  .machine-settings-grid { grid-template-columns: 1fr 1fr; }
}

/* ── 30. Print ──────────────────────────────────────────────── */
@media print {
  .sidebar, .topbar, .sidebar-toggle { display: none !important; }
  .main-content { margin-left: 0; }
  .card { box-shadow: none; border: 1px solid #ccc; break-inside: avoid; }
  body { background: #fff; color: #000; font-size: 12px; }
  .btn { display: none; }
  .table-wrapper { overflow: visible; }
}