/* =====================================================================
   AES-128 REGISTER TRACE SIMULATOR — design tokens
   Palette: dark ink lab-notebook. Teal = forward ops, Amber = key
   schedule, Red = inverse ops. Everything else is quiet grey/ink.
   ===================================================================== */
:root {
  --bg:          #070B10;
  --panel:       rgba(16, 22, 29, 0.84);
  --panel-2:     rgba(20, 27, 36, 0.95);
  --raised:      #1A2129;
  --hairline:    rgba(35, 43, 53, 0.92);
  --hairline-2:  rgba(46, 56, 68, 0.95);

  --text:        #E8ECEF;
  --text-dim:    #8B96A3;
  --text-faint:  #545F6C;

  --teal:        #4FD1C1;
  --teal-dim:    #2A4A47;
  --amber:       #E8A33D;
  --amber-dim:   #4A3B20;
  --red:         #E2604F;
  --red-dim:     #4A2A24;
  --blue:        #6C93F0;
  --blue-dim:    #24304A;

  --radius-sm: 3px;
  --radius-md: 6px;

  --font-display: 'JetBrains Mono', 'SFMono-Regular', monospace;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  -webkit-font-smoothing: antialiased;
}

body {
  background-image:
    radial-gradient(circle at top left, rgba(79, 209, 193, 0.12), transparent 28%),
    radial-gradient(circle at top right, rgba(108, 147, 240, 0.08), transparent 24%),
    linear-gradient(var(--hairline) 1px, transparent 1px),
    linear-gradient(90deg, var(--hairline) 1px, transparent 1px);
  background-size: auto, auto, 28px 28px, 28px 28px;
  background-attachment: fixed;
  background-position: -1px -1px;
  background-color: var(--bg);
}

button { font-family: inherit; }
input:focus-visible, button:focus-visible, .section-toggle:focus-visible {
  outline: 2px solid var(--teal);
  outline-offset: 2px;
}

code, .mono { font-family: var(--font-mono); }

/* ===================== LAYOUT SHELL ===================== */
.app {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 20px 60px;
  min-height: 100vh;
  position: relative;
}

.app::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(7, 11, 16, 0.18), rgba(7, 11, 16, 0.64));
  z-index: -1;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px 4px 18px;
  border-bottom: 1px solid var(--hairline);
  margin-bottom: 22px;
  backdrop-filter: blur(12px);
}

.brand { display: flex; align-items: baseline; gap: 10px; }
.brand-mark {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 22px;
  letter-spacing: 0.02em;
  color: var(--text);
  text-shadow: 0 0 22px rgba(79, 209, 193, 0.14);
}
.brand-mark::after { content: ''; }
.brand-sub {
  font-family: var(--font-display);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--teal);
}

.topbar-meta { display: flex; align-items: center; gap: 18px; }
.meta-item {
  font-size: 12px;
  color: var(--text-dim);
  display: flex;
  align-items: center;
  gap: 6px;
}
.dot { width: 6px; height: 6px; border-radius: 50%; background: var(--text-faint); }
.dot--ecb { background: var(--teal); box-shadow: 0 0 0 3px var(--teal-dim); }

.layout {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 24px;
  align-items: start;
}

.main { min-width: 0; }

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(320px, 0.9fr);
  gap: 20px;
  margin: 18px 0 24px;
}

.hero-copy,
.hero-panel {
  border: 1px solid var(--hairline);
  border-radius: 18px;
  background: linear-gradient(180deg, rgba(17, 23, 31, 0.92), rgba(14, 19, 26, 0.82));
  box-shadow: 0 24px 44px rgba(0, 0, 0, 0.24);
  backdrop-filter: blur(16px);
}

.hero-copy { padding: 28px 28px 26px; }

.hero-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--teal);
  margin-bottom: 12px;
}

.hero-kicker::before {
  content: '';
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--teal);
  box-shadow: 0 0 0 5px rgba(79, 209, 193, 0.12);
}

.hero h1 {
  margin: 0;
  font-size: clamp(28px, 3.2vw, 46px);
  line-height: 1.02;
  letter-spacing: -0.03em;
  color: var(--text);
}

.hero p {
  margin: 14px 0 0;
  max-width: 56ch;
  color: var(--text-dim);
  line-height: 1.7;
  font-size: 14px;
}

.hero-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 18px;
}

.hero-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 10px;
  border-radius: 999px;
  background: rgba(79, 209, 193, 0.08);
  border: 1px solid rgba(79, 209, 193, 0.16);
  color: var(--teal);
  font-size: 11px;
  letter-spacing: 0.04em;
}

.hero-chip sup { font-size: 0.7em; }

.hero-panel { padding: 22px; }

.hero-panel-label {
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-faint);
  margin-bottom: 16px;
}

.hero-formula {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8px 0 6px;
}

.hero-mini-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin-top: 12px;
}

.hero-mini-grid div {
  padding: 12px;
  border-radius: 12px;
  background: rgba(20, 27, 36, 0.72);
  border: 1px solid var(--hairline);
}

.hero-mini-grid span {
  display: block;
  color: var(--text-faint);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 6px;
}

.hero-mini-grid strong {
  display: block;
  color: var(--text);
  font-size: 13px;
  line-height: 1.4;
}

/* ===================== SIDEBAR ===================== */
.sidebar {
  position: sticky;
  top: 20px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  background: linear-gradient(180deg, rgba(16, 22, 29, 0.94), rgba(16, 22, 29, 0.76));
  padding: 14px 10px;
  max-height: calc(100vh - 40px);
  overflow-y: auto;
  box-shadow: 0 18px 42px rgba(0, 0, 0, 0.22);
}
.sidebar-label {
  font-size: 10px;
  letter-spacing: 0.1em;
  color: var(--text-faint);
  text-transform: uppercase;
  padding: 0 6px 10px;
}
.round-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 2px; }
.round-list li a {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 8px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--text-dim);
  font-family: var(--font-display);
  font-size: 12px;
  transition: background 0.12s, color 0.12s;
}
.round-list li a:hover { background: var(--raised); color: var(--text); }
.round-list li a.is-current { background: var(--teal-dim); color: var(--teal); }
.round-list li a .rn-tag {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--hairline-2); flex-shrink: 0;
}
.round-list li a.is-current .rn-tag { background: var(--teal); }
.round-list li.rn-key a .rn-tag { background: var(--amber); }

/* ===================== PANELS ===================== */
.panel {
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  background: linear-gradient(180deg, rgba(17, 23, 31, 0.92), rgba(14, 19, 26, 0.82));
  margin-bottom: 16px;
  box-shadow: 0 18px 42px rgba(0, 0, 0, 0.18);
  backdrop-filter: blur(14px);
}
.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 18px 0;
}
.panel-head h2 {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-dim);
  margin: 0;
}

.mode-switch { display: flex; gap: 2px; background: var(--panel-2); border: 1px solid var(--hairline); border-radius: var(--radius-sm); padding: 2px; }
.mode-btn {
  border: none; background: transparent; color: var(--text-dim);
  font-size: 12px; font-weight: 600; letter-spacing: 0.04em;
  padding: 6px 14px; border-radius: 2px; cursor: pointer;
  transition: background 0.12s, color 0.12s;
}
.mode-btn.is-active { background: var(--teal); color: #06120F; }
.mode-btn:not(.is-active):hover { color: var(--text); }

.input-grid { padding: 16px 18px 4px; display: flex; flex-direction: column; gap: 16px; }
.field label { display: flex; align-items: baseline; justify-content: space-between; font-size: 12px; font-weight: 600; color: var(--text); margin-bottom: 7px; }
.field-hint { font-size: 11px; font-weight: 400; color: var(--text-faint); }
.field-row { display: flex; gap: 8px; }
.field-input {
  flex: 1;
  background: var(--panel-2);
  border: 1px solid var(--hairline-2);
  color: var(--text);
  font-size: 13px;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  transition: border-color 0.12s, box-shadow 0.12s, transform 0.12s;
}
.field-input:hover { border-color: rgba(79, 209, 193, 0.36); }
.field-input:focus { border-color: var(--teal); outline: none; box-shadow: 0 0 0 3px rgba(79, 209, 193, 0.10); transform: translateY(-1px); }
.field-input::placeholder { color: var(--text-faint); }
.field-error { min-height: 16px; font-size: 11px; color: var(--red); margin-top: 5px; }

.format-toggle { display: flex; border: 1px solid var(--hairline-2); border-radius: var(--radius-sm); overflow: hidden; flex-shrink: 0; }
.fmt-btn { border: none; background: var(--panel-2); color: var(--text-faint); font-size: 11px; font-weight: 600; padding: 0 12px; cursor: pointer; }
.fmt-btn.is-active { background: var(--raised); color: var(--teal); }

.ghost-btn {
  border: 1px solid var(--hairline-2);
  background: transparent;
  color: var(--text-dim);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.04em;
  padding: 0 12px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  white-space: nowrap;
  transition: border-color 0.12s, color 0.12s;
}
.ghost-btn:hover { border-color: var(--teal); color: var(--teal); }

.action-row { display: flex; align-items: center; gap: 10px; padding: 18px; flex-wrap: wrap; }
.primary-btn {
  display: flex; align-items: center; gap: 8px;
  background: var(--teal); color: #06120F; border: none;
  font-size: 12px; font-weight: 700; letter-spacing: 0.06em;
  padding: 11px 18px; border-radius: var(--radius-sm); cursor: pointer;
  transition: filter 0.12s, transform 0.12s, box-shadow 0.12s;
  box-shadow: 0 10px 24px rgba(79, 209, 193, 0.16);
}
.primary-btn:hover { filter: brightness(1.08); transform: translateY(-1px); }
.primary-btn:active { transform: translateY(1px); }
.secondary-btn {
  background: transparent; border: 1px solid var(--hairline-2); color: var(--text-dim);
  font-size: 12px; font-weight: 600; letter-spacing: 0.05em;
  padding: 11px 16px; border-radius: var(--radius-sm); cursor: pointer;
}
.secondary-btn:hover { color: var(--red); border-color: var(--red); }

.toggle-row { display: flex; align-items: center; gap: 8px; margin-left: auto; cursor: pointer; user-select: none; }
.toggle-row input { display: none; }
.toggle-track { width: 30px; height: 17px; border-radius: 10px; background: var(--hairline-2); position: relative; transition: background 0.15s; flex-shrink: 0; }
.toggle-thumb { position: absolute; top: 2px; left: 2px; width: 13px; height: 13px; border-radius: 50%; background: var(--text-dim); transition: transform 0.15s, background 0.15s; }
.toggle-row input:checked + .toggle-track { background: var(--teal-dim); }
.toggle-row input:checked + .toggle-track .toggle-thumb { transform: translateX(13px); background: var(--teal); }
.toggle-label { font-size: 12px; color: var(--text-dim); }

.output-block { margin: 0 18px 18px; border-top: 1px dashed var(--hairline-2); padding-top: 14px; }
.output-label { font-size: 11px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--text-faint); margin-bottom: 8px; }
.output-row { display: flex; align-items: center; gap: 10px; }
.output-value {
  flex: 1;
  background: var(--panel-2);
  border: 1px solid var(--teal-dim);
  color: var(--teal);
  font-size: 14px;
  letter-spacing: 0.04em;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  word-break: break-all;
  box-shadow: inset 0 0 0 1px rgba(79, 209, 193, 0.08);
}

/* ===================== NOTICE ===================== */
.notice {
  display: flex; gap: 10px;
  border: 1px solid var(--amber-dim);
  background: linear-gradient(180deg, rgba(232,163,61,0.07), rgba(232,163,61,0.02));
  color: var(--text-dim);
  border-radius: var(--radius-md);
  padding: 13px 16px;
  font-size: 12.5px;
  line-height: 1.6;
  margin-bottom: 16px;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.14);
}
.notice svg { color: var(--amber); flex-shrink: 0; margin-top: 2px; }
.notice strong { color: var(--text); }
.notice code { background: var(--panel-2); padding: 1px 5px; border-radius: 3px; font-size: 11.5px; color: var(--amber); }

/* ===================== COLLAPSIBLE SECTIONS ===================== */
.section-toggle {
  width: 100%;
  display: flex; align-items: baseline; gap: 10px;
  background: transparent; border: none; cursor: pointer;
  padding: 16px 18px; text-align: left; color: var(--text);
}
.section-chevron { color: var(--text-faint); font-size: 11px; transition: transform 0.15s; flex-shrink: 0; }
.section-toggle[aria-expanded="false"] .section-chevron { transform: rotate(-90deg); }
.section-title { font-size: 13px; font-weight: 600; letter-spacing: 0.03em; }
.section-sub { font-size: 11px; color: var(--text-faint); margin-left: auto; font-family: var(--font-mono); }
.section-body { padding: 0 18px 18px; }
.section-body[hidden] { display: none; }

/* ===================== ROUNDS ===================== */
.rounds { display: flex; flex-direction: column; gap: 14px; }
.round-card { border: 1px solid var(--hairline); border-radius: 14px; background: linear-gradient(180deg, rgba(16, 22, 29, 0.92), rgba(14, 19, 26, 0.82)); scroll-margin-top: 16px; overflow: clip; box-shadow: 0 18px 40px rgba(0, 0, 0, 0.20); }
.round-card-head {
  width: 100%;
  display: flex; align-items: center; gap: 12px;
  background: transparent; border: none; cursor: pointer;
  padding: 15px 18px; text-align: left; color: var(--text);
  background: linear-gradient(180deg, rgba(255,255,255,0.03), transparent);
}
.round-badge {
  font-family: var(--font-display);
  font-size: 11px; font-weight: 700;
  padding: 4px 9px; border-radius: 20px;
  background: var(--panel-2); color: var(--text-dim);
  border: 1px solid var(--hairline-2);
  flex-shrink: 0;
}
.round-card.is-initial .round-badge { color: var(--blue); border-color: var(--blue-dim); background: var(--blue-dim); }
.round-card.is-final .round-badge { color: var(--red); border-color: var(--red-dim); background: var(--red-dim); }
.round-card-title { font-size: 13px; font-weight: 600; }
.round-card-sub { font-size: 11px; color: var(--text-faint); margin-left: auto; }

.op-list { display: flex; flex-direction: column; gap: 0; padding: 0 18px 18px; }
.op-step { border-top: 1px dashed var(--hairline); padding: 16px 0; }
.op-step:first-child { border-top: none; }
.op-step-head { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 10px; }
.op-tag {
  font-family: var(--font-display); font-size: 10.5px; font-weight: 700;
  letter-spacing: 0.04em; padding: 3px 8px; border-radius: 3px;
  text-transform: uppercase;
}
.op-tag--sub    { background: var(--teal-dim);  color: var(--teal); }
.op-tag--shift  { background: var(--teal-dim);  color: var(--teal); }
.op-tag--mix    { background: var(--blue-dim);  color: var(--blue); }
.op-tag--key    { background: var(--amber-dim); color: var(--amber); }
.op-tag--inv    { background: var(--red-dim);   color: var(--red); }
.op-desc { font-size: 11.5px; color: var(--text-faint); }
.math-line { min-height: 28px; margin-bottom: 12px; color: var(--text); }

.formula-callout {
  margin-bottom: 14px;
  padding: 14px;
  border-radius: 12px;
  background: rgba(20, 27, 36, 0.72);
  border: 1px solid var(--hairline);
}

.formula-callout-math {
  display: flex;
  justify-content: center;
  overflow-x: auto;
  padding-bottom: 8px;
}

.formula-callout-caption {
  font-size: 12px;
  color: var(--text-dim);
  line-height: 1.6;
}

.key-expansion-preview {
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-faint);
}

.matrix-pair { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; }
.matrix-arrow { color: var(--text-faint); font-size: 18px; flex-shrink: 0; align-self: center; }

.matrix-block-label { font-size: 10px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--text-faint); margin-bottom: 6px; }
.matrix-grid {
  display: grid;
  grid-template-columns: repeat(4, 34px);
  grid-template-rows: repeat(4, 34px);
  gap: 3px;
  background: var(--hairline);
  border: 1px solid var(--hairline);
  border-radius: 10px;
  overflow: hidden;
}
.byte-cell {
  background: var(--panel-2);
  display: flex; align-items: center; justify-content: center;
  font-family: var(--font-mono); font-size: 11.5px; font-weight: 500;
  color: var(--text-dim);
  transition: background 0.16s, color 0.16s, transform 0.16s;
}
.byte-cell:hover { background: rgba(79, 209, 193, 0.14); color: var(--text); transform: translateY(-1px); }
.byte-cell.is-empty { color: var(--text-faint); }
.byte-cell.is-changed { background: var(--teal-dim); color: var(--teal); font-weight: 700; }
.byte-cell.is-key { background: var(--amber-dim); color: var(--amber); }

.round-list li a { gap: 10px; }
.round-list li a .rn-tag { box-shadow: 0 0 0 1px rgba(255,255,255,0.06); }
.round-list li a.is-current { background: rgba(79, 209, 193, 0.14); color: var(--teal); }
.round-list li a:hover { transform: translateX(1px); }

.section-body h3 { margin: 16px 0 10px; font-size: 12px; text-transform: uppercase; letter-spacing: 0.06em; color: var(--teal); }

.key-expansion-summary { font-size: 12px; color: var(--text-dim); margin-bottom: 12px; }

.key-expansion-list,
.key-expansion-log { display: grid; gap: 8px; }

.key-expansion-item,
.key-expansion-log-item {
  border: 1px solid var(--hairline);
  background: rgba(20, 27, 36, 0.72);
  border-radius: 10px;
  padding: 10px 12px;
}

.key-expansion-item { display: grid; grid-template-columns: 56px 72px 1fr; gap: 10px; align-items: center; }
.key-expansion-label { font-family: var(--font-display); font-size: 11px; font-weight: 700; color: var(--amber); letter-spacing: 0.06em; }
.key-expansion-item code { color: var(--text-dim); word-break: break-word; font-size: 11px; }
.key-expansion-log-item { font-family: var(--font-mono); font-size: 11px; line-height: 1.5; color: var(--text-dim); }

.empty-state,
.rounds:empty::before {
  padding: 36px 20px;
  text-align: center;
  color: var(--text-faint);
  font-size: 12.5px;
  border: 1px dashed var(--hairline-2);
  border-radius: 14px;
  background: rgba(20, 27, 36, 0.42);
}

.rounds:empty::before {
  content: 'Run Encrypt / Decrypt untuk melihat trace langkah demi langkah.';
  display: block;
}

.empty-state {
  padding: 40px 20px;
  text-align: center;
  color: var(--text-faint);
  font-size: 12.5px;
  border: 1px dashed var(--hairline-2);
  border-radius: var(--radius-md);
}

.footer {
  text-align: center;
  color: var(--text-faint);
  font-size: 11px;
  padding-top: 30px;
  letter-spacing: 0.03em;
}

/* ===================== RESPONSIVE ===================== */
@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; }
  .hero { grid-template-columns: 1fr; }
  .sidebar {
    position: static;
    max-height: none;
    overflow: visible;
  }
  .round-list { flex-direction: row; flex-wrap: wrap; }
  .matrix-grid { grid-template-columns: repeat(4, 30px); grid-template-rows: repeat(4, 30px); }
  .action-row { flex-direction: column; align-items: stretch; }
  .toggle-row { margin-left: 0; }
  .hero-mini-grid { grid-template-columns: 1fr; }
  .key-expansion-item { grid-template-columns: 1fr; }
  .topbar { flex-direction: column; align-items: flex-start; gap: 10px; }
  .field label { flex-direction: column; align-items: flex-start; gap: 4px; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}