/* =====================================================================
   STACKVERSE — DESIGN SYSTEM
   Palette: warm daylight neutral base + solar-amber accent + deep ink text
   Type: 'Sora' (display, geometric, confident) + 'Inter' (body, workhorse)
   ===================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Sora:wght@400;500;600;700;800&family=Inter:wght@400;500;600;700&display=swap');

:root {
  /* ---- Color tokens ---- */
  --color-bg:            #FCFBF8;   /* warm paper white, not stark #fff */
  --color-surface:       #FFFFFF;
  --color-surface-alt:   #F5F3EE;
  --color-ink:           #12181B;   /* near-black, warm-neutral */
  --color-ink-soft:      #4A5257;
  --color-ink-faint:     #8A9096;
  --color-border:        #E7E3DA;
  --color-border-strong: #D8D2C4;

  --color-amber:         #F2A93B;   /* solar accent — the sun */
  --color-amber-dark:    #D68A1E;
  --color-amber-tint:    #FDF2DE;

  --color-deep:          #10242E;   /* deep teal-ink, "night sky" counterpoint */
  --color-deep-tint:     #E7EEF0;

  --color-success:       #1F8A57;
  --color-success-tint:  #E4F4EA;
  --color-warning:       #B4790A;
  --color-warning-tint:  #FBF0DA;
  --color-danger:        #C1352B;
  --color-danger-tint:   #FBE9E7;
  --color-info:          #2461A6;
  --color-info-tint:     #E7F0FA;

  /* ---- Typography ---- */
  --font-display: 'Sora', system-ui, sans-serif;
  --font-body:    'Inter', system-ui, sans-serif;

  --fs-h1: clamp(2.5rem, 4.5vw, 4.25rem);
  --fs-h2: clamp(2rem, 3vw, 2.75rem);
  --fs-h3: clamp(1.5rem, 2vw, 2rem);
  --fs-h4: 1.25rem;
  --fs-body-lg: 1.125rem;
  --fs-body: 1rem;
  --fs-small: 0.875rem;
  --fs-micro: 0.75rem;

  /* ---- Spacing scale ---- */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4.5rem;
  --space-9: 6.5rem;

  /* ---- Radius / shadow ---- */
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --radius-pill: 999px;

  --shadow-sm: 0 1px 2px rgba(18, 24, 27, 0.06), 0 1px 1px rgba(18,24,27,0.04);
  --shadow-md: 0 8px 24px rgba(18, 24, 27, 0.08);
  --shadow-lg: 0 20px 48px rgba(18, 24, 27, 0.12);
  --shadow-amber-glow: 0 8px 30px rgba(242, 169, 59, 0.35);

  --container-max: 1200px;
  --transition-base: 220ms cubic-bezier(.4,0,.2,1);
}

/* ---- Reset ---- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: var(--fs-body);
  color: var(--color-ink);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5 {
  font-family: var(--font-display);
  color: var(--color-ink);
  margin: 0 0 var(--space-4);
  line-height: 1.15;
  letter-spacing: -0.01em;
}
h1 { font-size: var(--fs-h1); font-weight: 700; }
h2 { font-size: var(--fs-h2); font-weight: 700; }
h3 { font-size: var(--fs-h3); font-weight: 600; }
h4 { font-size: var(--fs-h4); font-weight: 600; }
p { margin: 0 0 var(--space-4); color: var(--color-ink-soft); }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul, ol { padding-left: 1.2em; }
button { font-family: inherit; }

::selection { background: var(--color-amber); color: var(--color-ink); }

:focus-visible {
  outline: 2px solid var(--color-amber-dark);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---- Layout ---- */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-5);
}
@media (max-width: 640px) {
  .container { padding: 0 var(--space-4); }
}

.section { padding: var(--space-9) 0; }
.section-tight { padding: var(--space-7) 0; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-display);
  font-size: var(--fs-micro);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-amber-dark);
  background: var(--color-amber-tint);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-pill);
  margin-bottom: var(--space-4);
}

.section-head { max-width: 640px; margin-bottom: var(--space-7); }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }
.section-head p { font-size: var(--fs-body-lg); }

.grid { display: grid; gap: var(--space-5); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) {
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
}

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: var(--fs-body);
  padding: 0.85rem 1.6rem;
  border-radius: var(--radius-pill);
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform var(--transition-base), box-shadow var(--transition-base), background var(--transition-base), color var(--transition-base), border-color var(--transition-base);
  white-space: nowrap;
}
.btn:active { transform: translateY(1px) scale(0.99); }
.btn:disabled { opacity: 0.55; cursor: not-allowed; transform: none; }

.btn-primary {
  background: var(--color-ink);
  color: #fff;
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover:not(:disabled) { background: var(--color-deep); box-shadow: var(--shadow-md); transform: translateY(-1px); }

.btn-amber {
  background: var(--color-amber);
  color: var(--color-ink);
  box-shadow: var(--shadow-amber-glow);
}
.btn-amber:hover:not(:disabled) { background: var(--color-amber-dark); transform: translateY(-1px); }

.btn-outline {
  background: transparent;
  border-color: var(--color-border-strong);
  color: var(--color-ink);
}
.btn-outline:hover:not(:disabled) { border-color: var(--color-ink); background: var(--color-surface-alt); }

.btn-ghost {
  background: transparent;
  color: var(--color-ink-soft);
}
.btn-ghost:hover:not(:disabled) { background: var(--color-surface-alt); color: var(--color-ink); }

.btn-danger { background: var(--color-danger); color: #fff; }
.btn-danger:hover:not(:disabled) { background: #9E2A22; }

.btn-sm { padding: 0.55rem 1.1rem; font-size: var(--fs-small); }
.btn-lg { padding: 1.05rem 2.1rem; font-size: var(--fs-body-lg); }
.btn-block { width: 100%; }

/* ---- Cards ---- */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}
.card-hover:hover { box-shadow: var(--shadow-md); transform: translateY(-3px); }

.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--fs-micro);
  font-weight: 600;
  padding: 0.3rem 0.75rem;
  border-radius: var(--radius-pill);
  text-transform: capitalize;
}
.badge-submitted { background: var(--color-info-tint); color: var(--color-info); }
.badge-under_review { background: var(--color-warning-tint); color: var(--color-warning); }
.badge-approved { background: var(--color-success-tint); color: var(--color-success); }
.badge-rejected { background: var(--color-danger-tint); color: var(--color-danger); }
.badge-completed { background: var(--color-deep-tint); color: var(--color-deep); }

/* ---- Forms ---- */
.field { margin-bottom: var(--space-5); }
.field label {
  display: block;
  font-weight: 600;
  font-size: var(--fs-small);
  margin-bottom: var(--space-2);
  color: var(--color-ink);
}
.field .hint { font-size: var(--fs-micro); color: var(--color-ink-faint); margin-top: var(--space-1); }
.field .error-msg { font-size: var(--fs-micro); color: var(--color-danger); margin-top: var(--space-1); display: none; }
.field.has-error .error-msg { display: block; }
.field.has-error input, .field.has-error select, .field.has-error textarea { border-color: var(--color-danger); }

input, select, textarea {
  width: 100%;
  font-family: var(--font-body);
  font-size: var(--fs-body);
  color: var(--color-ink);
  background: var(--color-surface);
  border: 1.5px solid var(--color-border-strong);
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--color-amber-dark);
  box-shadow: 0 0 0 4px var(--color-amber-tint);
}
textarea { resize: vertical; min-height: 100px; }
.input-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-4); }
@media (max-width: 640px) { .input-row { grid-template-columns: 1fr; } }

.file-drop {
  border: 1.5px dashed var(--color-border-strong);
  border-radius: var(--radius-md);
  padding: var(--space-6);
  text-align: center;
  cursor: pointer;
  transition: border-color var(--transition-base), background var(--transition-base);
  background: var(--color-surface-alt);
}
.file-drop:hover, .file-drop.dragover { border-color: var(--color-amber-dark); background: var(--color-amber-tint); }
.file-drop input[type="file"] { display: none; }

.file-list { list-style: none; padding: 0; margin: var(--space-4) 0 0; display: flex; flex-direction: column; gap: var(--space-2); }
.file-list li {
  display: flex; align-items: center; justify-content: space-between;
  background: var(--color-surface); border: 1px solid var(--color-border);
  border-radius: var(--radius-sm); padding: var(--space-3) var(--space-4);
  font-size: var(--fs-small);
}
.file-list .remove-file { color: var(--color-danger); cursor: pointer; font-weight: 600; background: none; border: none; }

/* ---- Skeletons ---- */
.skeleton {
  background: linear-gradient(90deg, var(--color-surface-alt) 25%, #EBE7DD 37%, var(--color-surface-alt) 63%);
  background-size: 400% 100%;
  animation: skeleton-shimmer 1.4s ease infinite;
  border-radius: var(--radius-sm);
}
@keyframes skeleton-shimmer { 0% { background-position: 100% 50%; } 100% { background-position: 0 50%; } }

/* ---- Toasts ---- */
#toast-region {
  position: fixed;
  top: var(--space-5);
  right: var(--space-5);
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  max-width: 380px;
}
@media (max-width: 640px) {
  #toast-region { left: var(--space-4); right: var(--space-4); max-width: none; }
}
.toast {
  display: flex; align-items: flex-start; gap: var(--space-3);
  background: var(--color-ink); color: #fff;
  padding: var(--space-4) var(--space-5);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  font-size: var(--fs-small);
  animation: toast-in 260ms cubic-bezier(.2,.8,.2,1);
}
.toast.success { background: var(--color-success); }
.toast.error { background: var(--color-danger); }
.toast.info { background: var(--color-deep); }
.toast .toast-close { margin-left: auto; cursor: pointer; opacity: 0.7; background: none; border: none; color: inherit; font-size: 1rem; }
@keyframes toast-in { from { opacity: 0; transform: translateY(-8px); } to { opacity: 1; transform: translateY(0); } }
.toast.leaving { animation: toast-out 200ms ease forwards; }
@keyframes toast-out { to { opacity: 0; transform: translateX(20px); } }

/* ---- Utility ---- */
.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.flex { display: flex; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: var(--space-2); }
.gap-4 { gap: var(--space-4); }
.hidden { display: none !important; }
.text-muted { color: var(--color-ink-faint); }
.divider { height: 1px; background: var(--color-border); margin: var(--space-6) 0; border: none; }

/* ---- Reveal-on-scroll ---- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 700ms ease, transform 700ms ease; }
.reveal.in-view { opacity: 1; transform: translateY(0); }

/* ---- Back to top ---- */
#back-to-top {
  position: fixed; bottom: var(--space-5); right: var(--space-5);
  width: 46px; height: 46px; border-radius: 50%;
  background: var(--color-ink); color: #fff; border: none;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer; box-shadow: var(--shadow-md);
  opacity: 0; visibility: hidden; transform: translateY(10px);
  transition: all var(--transition-base);
  z-index: 500;
}
#back-to-top.visible { opacity: 1; visibility: visible; transform: translateY(0); }