/* ===================================================================
   ws1.3 SPA interface
   Modern data workspace styling with sage greens, warm beige surfaces,
   and matte black accents. AJAX behavior remains unchanged.
=================================================================== */

:root{
  --bg:             #e8dfcf;
  --bg-soft:        #f2eadc;
  --surface:        #fbf7ee;
  --surface-muted:  #efe6d3;
  --green-900:      #13281e;
  --green-800:      #1e3a2c;
  --green-700:      #2f5e45;
  --green-500:      #6f9674;
  --green-300:      #c5d6bd;
  --green-100:      #e6eee0;
  --matte:          #141512;
  --matte-soft:     #2d302a;
  --text:           #1f241d;
  --text-muted:     #626b59;
  --line:           #d8cbb7;
  --line-strong:    #9a8f7d;
  --code-bg:        #f6f0e5;
  --shadow:         0 28px 70px -42px rgba(20, 21, 18, .72);
}

*{ box-sizing:border-box; }

html{
  min-height:100%;
  background: var(--bg);
}

body{
  margin:0;
  min-height:100vh;
  color: var(--text);
  font-family:'Inter', system-ui, sans-serif;
  padding: 28px 18px 72px;
  background:
    linear-gradient(90deg, rgba(19, 40, 30, .08) 0 1px, transparent 1px),
    linear-gradient(180deg, rgba(19, 40, 30, .08) 0 1px, transparent 1px),
    linear-gradient(135deg, rgba(251, 247, 238, .92), rgba(232, 223, 207, .96)),
    var(--bg);
  background-size: 120px 120px, 120px 120px, auto;
}

body::before{
  content:"";
  position:fixed;
  inset:0;
  pointer-events:none;
  background:
    linear-gradient(120deg, transparent 0 60%, rgba(47, 94, 69, .12) 60% 75%, transparent 75%),
    linear-gradient(180deg, rgba(251, 247, 238, .28), transparent 48%);
}

/* -------------------- application shell -------------------- */
.notebook{
  width:min(1180px, 100%);
  margin: 0 auto;
  position: relative;
  isolation:isolate;
}

.notebook::before{
  content:"";
  position:absolute;
  inset: 28px -14px -18px;
  z-index:-1;
  border-radius: 16px;
  background: rgba(19, 40, 30, .12);
  filter: blur(24px);
}

/* -------------------- header -------------------- */
.masthead{
  position:relative;
  overflow:hidden;
  display:grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 28px;
  align-items:end;
  min-height: 208px;
  padding: 42px 48px 38px;
  color: var(--surface);
  background:
    linear-gradient(110deg, rgba(19, 40, 30, .98), rgba(30, 58, 44, .96) 56%, rgba(20, 21, 18, .98)),
    var(--green-900);
  border: 1px solid rgba(251, 247, 238, .12);
  border-radius: 16px 16px 0 0;
  box-shadow: var(--shadow);
}

.masthead::before{
  content:"";
  position:absolute;
  right:42px;
  top:34px;
  width: 210px;
  height: 126px;
  border: 1px solid rgba(197, 214, 189, .18);
  border-radius: 12px;
  background:
    linear-gradient(90deg, rgba(197, 214, 189, .16) 0 35%, transparent 35%),
    linear-gradient(rgba(251,247,238,.08) 1px, transparent 1px);
  background-size: auto, 100% 24px;
}

.masthead::after{
  content:"";
  position:absolute;
  left:48px;
  right:48px;
  bottom:0;
  height:1px;
  background: linear-gradient(90deg, rgba(251,247,238,.42), transparent);
}

.kicker{
  position:relative;
  display:inline-flex;
  align-items:center;
  gap: 9px;
  margin: 0 0 14px;
  color: var(--green-300);
  font-family:'Space Mono', monospace;
  font-size:.72rem;
  letter-spacing:.16em;
  text-transform:uppercase;
}

.kicker::before{
  content:"";
  width: 28px;
  height: 2px;
  background: var(--green-300);
}

.masthead h1{
  position:relative;
  grid-column: 1;
  max-width: 720px;
  margin: 0 0 12px;
  font-family:'Space Mono', monospace;
  font-weight:700;
  font-size: clamp(2rem, 5vw, 4.1rem);
  line-height: 1;
  letter-spacing:0;
}

.masthead p{
  position:relative;
  grid-column: 1;
  max-width: 62ch;
  margin:0;
  color: rgba(251, 247, 238, .76);
  font-size: .98rem;
  line-height: 1.7;
}

/* -------------------- navigation tabs -------------------- */
.tabs{
  display:flex;
  align-items:stretch;
  gap: 12px;
  padding: 14px 16px;
  background: var(--matte);
  border-left: 1px solid var(--matte);
  border-right: 1px solid var(--matte);
}

.tab{
  flex: 1 1 0;
  min-height: 68px;
  padding: 15px 18px;
  border: 1px solid rgba(251, 247, 238, .1);
  border-radius: 8px;
  color: rgba(251, 247, 238, .68);
  background: rgba(251, 247, 238, .04);
  font-family:'Space Mono', monospace;
  font-size:.82rem;
  font-weight:700;
  letter-spacing:.02em;
  text-align:left;
  cursor: pointer;
  transition: background .2s ease, color .2s ease, transform .2s ease;
}

.tab .num{
  display:inline-block;
  margin: 0 10px 0 0;
  color: var(--green-300);
  font-size:.72rem;
  letter-spacing:.14em;
}

.tab:hover{
  color: var(--surface);
  background: var(--matte-soft);
}

.tab[aria-selected="true"]{
  color: var(--green-900);
  background: var(--green-300);
  border-color: var(--green-300);
  box-shadow: 0 10px 24px -18px rgba(197, 214, 189, .9);
}

.tab[aria-selected="true"] .num{ color: var(--green-700); }

/* -------------------- main content -------------------- */
.page{
  min-height: 450px;
  padding: 28px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-top:0;
  border-radius: 0 0 16px 16px;
  box-shadow: var(--shadow);
}

.page-inner{
  padding: 30px;
  border-radius: 12px;
  background: var(--bg-soft);
  border: 1px solid rgba(47, 94, 69, .18);
}

/* -------------------- sheet content -------------------- */
.sheet-head{
  display:flex;
  align-items:flex-start;
  gap: 18px;
  margin-bottom: 26px;
  flex-wrap: wrap;
}

.tab-index{
  display:grid;
  place-items:center;
  flex: 0 0 auto;
  width: 54px;
  height: 54px;
  border-radius: 8px;
  color: var(--green-900);
  background: var(--green-300);
  font-family:'Space Mono', monospace;
  font-size: 1.08rem;
  font-weight: 700;
  line-height: 1;
  box-shadow: inset 0 -3px 0 rgba(0, 0, 0, .18);
}

.sheet-head > div{ flex: 1 1 260px; min-width: 180px; }

.sheet-head h2{
  margin: 0 0 6px;
  color: var(--green-900);
  font-family:'Space Mono', monospace;
  font-size: clamp(1.15rem, 3vw, 1.55rem);
  letter-spacing:0;
}

.sheet[data-sheet="1.2"] .sheet-head{
  align-items:center;
  padding: 18px;
  border: 1px solid rgba(47, 94, 69, .18);
  border-radius: 10px;
  background:
    linear-gradient(135deg, rgba(251, 247, 238, .94), rgba(230, 238, 224, .7)),
    var(--surface);
}

.sheet[data-sheet="1.2"] .tab-index{
  color: var(--surface);
  background: var(--matte);
}

.sheet-sub{
  margin:0;
  color: var(--text-muted);
  font-size: .95rem;
  line-height: 1.6;
}

.records{
  display:grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 18px;
  margin-bottom: 22px;
}

.record{
  position:relative;
  overflow:hidden;
  min-height: 190px;
  padding: 22px;
  border: 1px solid rgba(47, 94, 69, .2);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 18px 38px -34px rgba(20, 21, 18, .72);
}

.record::before{
  content:"";
  position:absolute;
  inset:0 0 auto 0;
  width: auto;
  height: 5px;
  background: var(--green-700);
}

.record-label{
  margin: 0 0 16px;
  color: var(--green-700);
  font-family:'Space Mono', monospace;
  font-weight:700;
  font-size:.78rem;
  text-transform: uppercase;
  letter-spacing:.09em;
}

.record-grid{
  margin:0;
  display:grid;
  grid-template-columns: minmax(82px, max-content) 1fr;
  gap: 7px 14px;
  font-size: .9rem;
  line-height: 1.45;
}

.record-grid dt{
  color: var(--matte-soft);
  font-family:'Space Mono', monospace;
  font-size: .76rem;
  text-transform: uppercase;
}

.record-grid dd{
  margin:0;
  color: var(--text);
}

.dump{
  padding-top: 14px;
  border-top: 1px solid var(--line);
}

.dump summary{
  cursor:pointer;
  color: var(--green-800);
  font-family:'Space Mono', monospace;
  font-size:.82rem;
  font-weight:700;
}

.dump pre{
  margin-top: 12px;
  padding: 16px;
  overflow-x:auto;
  color: var(--green-100);
  background: var(--matte);
  border: 1px solid rgba(251, 247, 238, .1);
  border-radius: 8px;
  font-family:'IBM Plex Mono', 'Space Mono', monospace;
  font-size: .78rem;
  line-height: 1.55;
}

.table-wrap{
  overflow-x:auto;
  border: 1px solid rgba(47, 94, 69, .22);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: 0 18px 42px -36px rgba(20, 21, 18, .7);
}

.ledger{
  width:100%;
  min-width: 680px;
  border-collapse: collapse;
  font-size: .84rem;
}

.ledger th{
  padding: 13px 14px;
  color: var(--surface);
  background: var(--matte);
  border-bottom: 1px solid rgba(251, 247, 238, .14);
  font-family:'Space Mono', monospace;
  text-align:left;
  font-size:.7rem;
  text-transform:uppercase;
  letter-spacing:.06em;
  white-space: nowrap;
}

.ledger td{
  padding: 11px 14px;
  border-bottom: 1px solid var(--line);
  color: var(--text);
  background: rgba(251, 247, 238, .74);
}

.ledger tbody tr:nth-child(even) td{ background: rgba(230, 238, 224, .6); }
.ledger tbody tr:hover td{ background: rgba(197, 214, 189, .8); }

.table-note{
  margin: 12px 0 0;
  color: var(--text-muted);
  font-size: .8rem;
  font-style: italic;
  line-height: 1.5;
}

/* -------------------- loading state -------------------- */
.loading{
  display:flex;
  align-items:center;
  gap:12px;
  min-height: 160px;
  padding: 30px 0;
  color: var(--green-800);
  font-family:'Space Mono', monospace;
  font-size:.9rem;
}

.loading::before{
  content:"";
  width:12px;
  height:12px;
  border-radius:50%;
  background: var(--green-700);
  box-shadow: 0 0 0 0 rgba(47, 94, 69, .32);
  animation: pulse 1.2s ease-in-out infinite;
}

@keyframes pulse{
  0%,100%{ opacity:.42; transform:scale(.85); box-shadow: 0 0 0 0 rgba(47, 94, 69, .32); }
  50%{ opacity:1; transform:scale(1.08); box-shadow: 0 0 0 9px rgba(47, 94, 69, 0); }
}

.site-footer{
  display:flex;
  align-items:center;
  justify-content:center;
  gap: 16px;
  flex-wrap:wrap;
  margin-top: 18px;
  padding: 16px 20px;
  color: var(--surface);
  background: var(--matte);
  border: 1px solid rgba(251, 247, 238, .1);
  border-radius: 12px;
}

.instructor-label,
.footer-note{
  margin:0;
  color: rgba(251, 247, 238, .62);
  font-family:'Space Mono', monospace;
  font-size:.74rem;
  text-transform:uppercase;
  letter-spacing:.1em;
}

.instructor-name{
  margin:0;
  color: var(--green-300);
  font-family:'Inter', system-ui, sans-serif;
  font-size:.95rem;
  font-weight:700;
}

.footer-note{
  flex-basis:100%;
  text-align:center;
  text-transform:none;
  letter-spacing:0;
}

/* -------------------- table picker -------------------- */
.table-picker-btn{
  align-self:center;
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap: 10px;
  min-height: 54px;
  padding: 10px 18px 10px 14px;
  border: 1px solid rgba(19, 40, 30, .18);
  border-radius: 10px;
  color: var(--green-900);
  background:
    linear-gradient(180deg, #dce9d2, #b9cdae),
    var(--green-300);
  font-family:'Space Mono', monospace;
  font-size: .78rem;
  font-weight: 700;
  cursor: pointer;
  white-space: nowrap;
  box-shadow:
    inset 0 -2px 0 rgba(19, 40, 30, .14),
    0 16px 30px -24px rgba(20, 21, 18, .8);
  transition: transform .12s ease, box-shadow .16s ease, filter .16s ease;
}

.table-picker-btn::before{
  content:"";
  width: 30px;
  height: 30px;
  flex: 0 0 auto;
  border-radius: 8px;
  background:
    linear-gradient(var(--green-900), var(--green-900)) center 9px / 14px 2px no-repeat,
    linear-gradient(var(--green-900), var(--green-900)) center 15px / 14px 2px no-repeat,
    linear-gradient(var(--green-900), var(--green-900)) center 21px / 14px 2px no-repeat,
    rgba(251, 247, 238, .72);
}

.table-picker-btn:hover{
  transform: translateY(-2px);
  filter: saturate(1.04);
  box-shadow:
    inset 0 -2px 0 rgba(19, 40, 30, .14),
    0 22px 34px -24px rgba(20, 21, 18, .86);
}

.table-picker-btn:active{ transform: translateY(1px); }

.table-picker-btn .current-table{
  display:inline-flex;
  align-items:center;
  min-height: 26px;
  padding: 4px 8px;
  border-radius: 999px;
  color: var(--surface);
  background: var(--green-800);
  font-weight: 700;
}

dialog.table-modal{
  width: min(760px, calc(100% - 38px));
  max-width: 760px;
  padding: 0;
  border: none;
  border-radius: 12px;
  background: transparent;
}

dialog.table-modal::backdrop{
  background: rgba(20, 21, 18, .58);
  backdrop-filter: blur(3px);
}

.modal-card{
  overflow:hidden;
  color: var(--text);
  background: var(--bg-soft);
  border: 1px solid rgba(251, 247, 238, .3);
  border-radius: 12px;
  box-shadow: 0 34px 70px -34px rgba(0,0,0,.72);
}

.modal-head{
  display:flex;
  align-items:center;
  justify-content: space-between;
  padding: 20px 22px;
  color: var(--surface);
  background:
    linear-gradient(110deg, var(--matte), var(--green-900));
}

.modal-head h3{
  margin:0;
  font-family:'Space Mono', monospace;
  font-size: 1rem;
}

.modal-close{
  display:grid;
  place-items:center;
  width: 34px;
  height: 34px;
  padding: 0;
  border: 1px solid rgba(251, 247, 238, .18);
  border-radius: 50%;
  color: var(--surface);
  background: rgba(251, 247, 238, .08);
  font-size: 1.35rem;
  line-height: 1;
  cursor: pointer;
}

.modal-close:hover{
  color: var(--green-900);
  background: var(--green-300);
}

.modal-options{
  display:grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 12px;
  padding: 22px;
  background:
    linear-gradient(180deg, rgba(251, 247, 238, .74), rgba(230, 238, 224, .6)),
    var(--bg-soft);
}

.table-option{
  position:relative;
  min-height: 82px;
  padding: 38px 14px 13px;
  border: 1px solid rgba(47, 94, 69, .18);
  border-radius: 10px;
  color: var(--text);
  background: var(--surface);
  font-family:'Space Mono', monospace;
  font-size: .8rem;
  text-align:center;
  cursor: pointer;
  box-shadow: 0 16px 30px -28px rgba(20, 21, 18, .7);
  transition: background .15s ease, transform .12s ease, border-color .15s ease, color .15s ease, box-shadow .15s ease;
}

.table-option::before{
  content:"";
  position:absolute;
  top: 14px;
  left: 50%;
  width: 24px;
  height: 16px;
  border: 2px solid currentColor;
  border-top-width: 5px;
  border-radius: 4px;
  transform: translateX(-50%);
  opacity:.58;
}

.table-option:hover{
  transform: translateY(-3px);
  border-color: var(--green-500);
  background: var(--green-100);
  box-shadow: 0 22px 34px -28px rgba(20, 21, 18, .82);
}

.table-option.active{
  color: var(--surface);
  background:
    linear-gradient(145deg, var(--green-800), var(--green-900));
  border-color: var(--green-700);
  box-shadow: inset 0 0 0 1px rgba(251, 247, 238, .08);
}

@media (max-width: 720px){
  body{ padding: 18px 12px 48px; }
  .masthead{ display:block; min-height: 0; padding: 34px 24px 26px; border-radius: 14px 14px 0 0; }
  .masthead::before{ display:none; }
  .masthead::after{ left:24px; right:24px; }
  .tabs{ flex-direction:column; }
  .tab{ min-height: 58px; }
  .page{ padding: 18px; border-radius: 0 0 14px 14px; }
  .page-inner{ padding: 22px 18px; border-radius: 10px; }
  .record-grid{ grid-template-columns: 1fr; gap: 3px 0; }
  .table-picker-btn{ width:100%; }
  .sheet[data-sheet="1.2"] .sheet-head{ padding: 14px; }
  .site-footer{ align-items:flex-start; flex-direction:column; gap: 6px; }
  .footer-note{ flex-basis:auto; text-align:left; }
  .modal-options{ grid-template-columns: 1fr; }
}

@media (max-width: 440px){
  .masthead h1{ font-size: 2rem; }
  .sheet-head{ gap: 12px; }
  .tab-index{ width: 46px; height: 46px; border-radius: 12px; }
  .records{ grid-template-columns: 1fr; }
}