/* ========================================================================== 
   Variables
   ========================================================================== */
:root {
  /* Color palette - energetic, bold, modern */
  --color-background: #050509;
  --color-surface: #0c0c12;
  --color-surface-alt: #14141f;
  --color-text: #f5f5f7;
  --color-text-muted: #b0b3c1;

  --color-primary: #ff2155; /* Energetic accent */
  --color-primary-soft: rgba(255, 33, 85, 0.12);
  --color-primary-strong: #ff426e;

  --color-success: #30d158;
  --color-warning: #ffd60a;
  --color-danger: #ff453a;

  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2933;
  --gray-900: #111827;

  /* Typography */
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-display: "Montserrat", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;

  --font-size-xs: 0.75rem;   /* 12px */
  --font-size-sm: 0.875rem;  /* 14px */
  --font-size-base: 1rem;    /* 16px */
  --font-size-lg: 1.125rem;  /* 18px */
  --font-size-xl: 1.25rem;   /* 20px */
  --font-size-2xl: 1.5rem;   /* 24px */
  --font-size-3xl: 1.875rem; /* 30px */
  --font-size-4xl: 2.25rem;  /* 36px */
  --font-size-5xl: 3rem;     /* 48px */

  --line-height-tight: 1.15;
  --line-height-snug: 1.3;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.7;

  /* Spacing scale (px converted to rem, root 16px) */
  --space-0: 0;
  --space-1: 0.25rem;  /* 4px */
  --space-2: 0.5rem;   /* 8px */
  --space-3: 0.75rem;  /* 12px */
  --space-4: 1rem;     /* 16px */
  --space-5: 1.25rem;  /* 20px */
  --space-6: 1.5rem;   /* 24px */
  --space-8: 2rem;     /* 32px */
  --space-10: 2.5rem;  /* 40px */
  --space-12: 3rem;    /* 48px */
  --space-16: 4rem;    /* 64px */
  --space-20: 5rem;    /* 80px */
  --space-24: 6rem;    /* 96px */

  /* Radius */
  --radius-xs: 0.125rem;
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-pill: 999px;

  /* Shadows - dynamic, gym-like depth */
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.5);
  --shadow-sm: 0 4px 10px rgba(0, 0, 0, 0.6);
  --shadow-md: 0 12px 30px rgba(0, 0, 0, 0.7);
  --shadow-glow: 0 0 0 1px rgba(255, 33, 85, 0.5), 0 0 20px rgba(255, 33, 85, 0.5);

  /* Transitions */
  --transition-fast: 120ms ease-out;
  --transition-base: 200ms ease-out;
  --transition-slow: 320ms ease-out;

  /* Layout */
  --container-width: 1200px;
  --container-padding-x: var(--space-4);
}

/* Prefer reduced motion */
@media (prefers-reduced-motion: reduce) {
  :root {
    --transition-fast: 0ms;
    --transition-base: 0ms;
    --transition-slow: 0ms;
  }

  *, *::before, *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* ========================================================================== 
   Reset / Normalize
   ========================================================================== */
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  margin: 0;
  padding: 0;
  scroll-behavior: smooth;
  text-size-adjust: 100%;
}

body {
  margin: 0;
}

h1, h2, h3, h4, h5, h6,
p, figure, blockquote,
dl, dd {
  margin: 0;
}

ul[role='list'],
ol[role='list'] {
  list-style: none;
  padding-left: 0;
  margin: 0;
}

img, picture, video, canvas, svg {
  display: block;
  max-width: 100%;
}

input, button, textarea, select {
  font: inherit;
}

button {
  border: none;
  background: none;
  padding: 0;
}

a {
  color: inherit;
  text-decoration: none;
}

/* ========================================================================== 
   Base Styles
   ========================================================================== */
body {
  min-height: 100vh;
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background-color: var(--color-background);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

main {
  display: block;
}

p {
  margin-bottom: var(--space-4);
  color: var(--color-text-muted);
  }

p:last-child {
  margin-bottom: 0;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: var(--line-height-tight);
  letter-spacing: 0.02em;
  color: var(--color-text);
  margin: 0 0 var(--space-3);
}

h1 {
  font-size: var(--font-size-5xl);
}

h2 {
  font-size: var(--font-size-4xl);
}

h3 {
  font-size: var(--font-size-3xl);
}

h4 {
  font-size: var(--font-size-2xl);
}

h5 {
  font-size: var(--font-size-xl);
}

h6 {
  font-size: var(--font-size-lg);
}

@media (max-width: 768px) {
  h1 { font-size: 2.4rem; }
  h2 { font-size: 2rem; }
  h3 { font-size: 1.6rem; }
}

a {
  position: relative;
  color: var(--color-primary);
  transition: color var(--transition-base);
}

a:hover {
  color: var(--color-primary-strong);
}

/* Underline on hover for content links */
.prose a {
  text-decoration: none;
}

.prose a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -0.15em;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-strong));
  transform-origin: left;
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

.prose a:hover::after {
  transform: scaleX(1);
}

strong, b {
  font-weight: 700;
}

small {
  font-size: var(--font-size-xs);
}

code, pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
}

hr {
  border: 0;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  margin: var(--space-6) 0;
}

/* ========================================================================== 
   Accessibility & Focus
   ========================================================================== */
:focus {
  outline: none;
}

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
}

/* Visually hidden but accessible */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ========================================================================== 
   Utilities
   ========================================================================== */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--container-padding-x);
  padding-right: var(--container-padding-x);
}

.section {
  padding-top: var(--space-16);
  padding-bottom: var(--space-16);
}

@media (max-width: 768px) {
  .section {
    padding-top: var(--space-10);
    padding-bottom: var(--space-10);
  }
}

/* Flex helpers */
.flex {
  display: flex;
}

.inline-flex {
  display: inline-flex;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

.flex-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.flex-col {
  flex-direction: column;
}

.flex-wrap {
  flex-wrap: wrap;
}

.gap-2 { gap: var(--space-2); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }

/* Grid helpers */
.grid {
  display: grid;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-6);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-6);
}

@media (max-width: 960px) {
  .grid-2, .grid-3 {
    grid-template-columns: minmax(0, 1fr);
  }
}

.text-center { text-align: center; }
.text-right { text-align: right; }

.mt-0 { margin-top: 0; }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mb-0 { margin-bottom: 0; }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }

.max-w-prose {
  max-width: 70ch;
}

.badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-pill);
  font-size: var(--font-size-xs);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  background: rgba(255, 255, 255, 0.06);
  color: var(--color-text-muted);
}

/* ========================================================================== 
   Components
   ========================================================================== */
/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  font-family: var(--font-display);
  font-size: var(--font-size-sm);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  cursor: pointer;
  transition: 
    background-color var(--transition-base),
    color var(--transition-base),
    border-color var(--transition-base),
    box-shadow var(--transition-base),
    transform var(--transition-fast);
  text-align: center;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-strong));
  color: #ffffff;
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-glow);
}

.btn-outline {
  background-color: transparent;
  border-color: rgba(255, 255, 255, 0.24);
  color: var(--color-text);
}

.btn-outline:hover {
  border-color: var(--color-primary);
  background-color: rgba(255, 33, 85, 0.08);
}

.btn-ghost {
  background-color: rgba(255, 255, 255, 0.04);
  color: var(--color-text);
}

.btn-ghost:hover {
  background-color: rgba(255, 255, 255, 0.08);
}

.btn:disabled,
.btn[aria-disabled="true"] {
  opacity: 0.6;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
}

.btn:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
}

/* Inputs */
.input,
.select,
.textarea {
  width: 100%;
  padding: 0.75rem 0.9rem;
  border-radius: var(--radius-md);
  border: 1px solid rgba(255, 255, 255, 0.14);
  background-color: var(--color-surface);
  color: var(--color-text);
  font-size: var(--font-size-sm);
  line-height: var(--line-height-normal);
  transition: border-color var(--transition-base), box-shadow var(--transition-base), background-color var(--transition-base);
}

.input::placeholder,
.textarea::placeholder {
  color: var(--color-text-muted);
}

.input:focus-visible,
.select:focus-visible,
.textarea:focus-visible {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 1px rgba(255, 33, 85, 0.7);
}

.input:disabled,
.select:disabled,
.textarea:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.textarea {
  min-height: 120px;
  resize: vertical;
}

label {
  display: inline-block;
  margin-bottom: 0.4rem;
  font-size: var(--font-size-sm);
  font-weight: 600;
}

.form-field {
  margin-bottom: var(--space-4);
}

.form-error {
  margin-top: 0.3rem;
  font-size: var(--font-size-xs);
  color: var(--color-danger);
}

/* Card */
.card {
  background: radial-gradient(circle at top left, rgba(255, 33, 85, 0.12), transparent 55%), var(--color-surface);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
  border: 1px solid rgba(255, 255, 255, 0.04);
}

.card-header {
  margin-bottom: var(--space-4);
}

.card-title {
  font-size: var(--font-size-xl);
  margin-bottom: var(--space-1);
}

.card-subtitle {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.card-body {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

/* Hero-like overlay utility for dynamic gym visuals */
.overlay-gradient {
  position: relative;
}

.overlay-gradient::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(120deg, rgba(5, 5, 9, 0.9) 0%, rgba(5, 5, 9, 0.5) 40%, rgba(5, 5, 9, 0.96) 100%);
  pointer-events: none;
}

/* Tag-like pill used for categories (e.g., beginner / advanced) */
.pill {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(255, 255, 255, 0.16);
  font-size: var(--font-size-xs);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
}

/* Schedule-like list styling helper */
.list-clean {
  list-style: none;
  padding: 0;
  margin: 0;
}

.list-clean li {
  padding: 0.5rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.list-clean li:last-child {
  border-bottom: none;
}

/* Chips for trainers' specialties */
.chip {
  display: inline-flex;
  align-items: center;
  padding: 0.3rem 0.8rem;
  border-radius: var(--radius-pill);
  background-color: rgba(255, 255, 255, 0.08);
  font-size: var(--font-size-xs);
  color: var(--color-text);
}

.chip + .chip {
  margin-left: 0.4rem;
}

/* ========================================================================== 
   Media Queries for Layout Tweaks
   ========================================================================== */
@media (max-width: 640px) {
  :root {
    --container-padding-x: var(--space-4);
  }

  .card {
    padding: var(--space-4);
  }
}