@import url('https://fonts.googleapis.com/css2?family=Share+Tech+Mono&display=swap');

:root {
  --bg-deep: #0a0c14;
  --bg-panel: #111420;
  --bg-card: #161a28;
  --bg-card2: #1c2035;
  --accent: #f5a623;
  --accent2: #7b5ea7;
  --accent3: #00ff9d;
  --accent-warn: #ffb347;
  --accent-danger: #ff4f6d;
  --border: rgba(0, 212, 255, 0.18);
  --border2: rgba(123, 94, 167, 0.25);
  --text-main: #e8eaf6;
  --text-dim: #8892b0;
  --text-label: #a8b2d8;
  --mono: 'Share Tech Mono', monospace;
  --sans: 'Calibri', 'Segoe UI', Arial, sans-serif;
  --radius: 10px;
  --radius-sm: 6px;
  --glow: 0 0 18px rgba(0, 212, 255, 0.22);
  --glow2: 0 0 18px rgba(123, 94, 167, 0.30);
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background: var(--bg-deep);
  color: var(--text-main);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.6;
  min-height: 100vh;
}

/* ─── HEADER ─── */
header {
  background: linear-gradient(135deg, #0d1021 0%, #111827 60%, #0a0c14 100%);
  border-bottom: 1px solid var(--border);
  padding: 28px 0 24px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

header::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 70% 80% at 50% 0%, rgba(0, 212, 255, 0.07) 0%, transparent 70%);
  pointer-events: none;
}

.header-badge {
  display: inline-block;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 3px;
  color: var(--accent);
  background: rgba(0, 212, 255, 0.08);
  border: 1px solid rgba(0, 212, 255, 0.25);
  border-radius: 20px;
  padding: 4px 16px;
  margin-bottom: 14px;
  text-transform: uppercase;
}

header h1 {
  font-family: var(--sans);
  font-size: 4.3rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  color: #fff;
  margin-bottom: 6px;
}

header h1 span {
  color: var(--accent);
}

header p {
  color: var(--text-dim);
  font-size: 14px;
  font-family: var(--sans);
}

/* ─── LAYOUT ─── */
.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 32px 20px 60px;
}

/* ─── CARD ─── */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  margin-bottom: 24px;
}

.card-title {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.card-title::after {
  content: '';
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--border), transparent);
}

/* ─── FORM ─── */
.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

@media (max-width: 600px) {
  .form-grid {
    grid-template-columns: 1fr;
  }
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.form-group label {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--text-label);
}

.form-group .hint {
  font-size: 11px;
  color: var(--text-dim);
  margin-top: -4px;
}

.form-group input,
.form-group select {
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-main);
  font-family: var(--mono);
  font-size: 15px;
  letter-spacing: 2px;
  padding: 12px 16px;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
  width: 100%;
}

.form-group select {
  font-family: var(--sans);
  letter-spacing: 0;
  cursor: pointer;
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 16 16'%3E%3Cpath fill='%2300d4ff' d='M8 11L2 5h12z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  background-size: 12px;
  padding-right: 36px;
}

.form-group input:focus,
.form-group select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.12);
}

.form-group input.error {
  border-color: var(--accent-danger);
}

.form-group .err-msg {
  font-size: 11px;
  color: var(--accent-danger);
  display: none;
}

.form-group.has-error .err-msg {
  display: block;
}

.form-group.has-error input {
  border-color: var(--accent-danger);
}

/* ─── BUTTONS ─── */
.btn-row {
  display: flex;
  gap: 14px;
  margin-top: 24px;
}

.btn {
  flex: 1;
  padding: 13px 20px;
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--sans);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 1px;
  cursor: pointer;
  transition: all 0.2s;
  text-transform: uppercase;
}

.btn-primary {
  background: linear-gradient(135deg, #f5a623, #f5a623);
  color: #fff;
  box-shadow: 0 4px 18px rgba(0, 153, 187, 0.35);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 24px rgb(245, 166, 35)
}

.btn-reset {
  background: transparent;
  color: var(--text-dim);
  border: 1px solid rgba(136, 146, 176, 0.3);
}

.btn-reset:hover {
  border-color: var(--text-dim);
  color: var(--text-main);
}

/* ─── BIT CELLS ─── */
.bit-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 8px 0;
  align-items: center;
}

.bit-cell {
  width: 38px;
  height: 38px;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: 6px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-family: var(--mono);
  position: relative;
}

.bit-cell .bit-idx {
  font-size: 8px;
  color: var(--text-dim);
  line-height: 1;
  margin-bottom: 1px;
}

.bit-cell .bit-val {
  font-size: 16px;
  font-weight: 700;
  line-height: 1;
}

.bit-cell.b1 {
  background: rgba(0, 212, 255, 0.10);
  border-color: rgba(0, 212, 255, 0.4);
  color: var(--accent);
}

.bit-cell.b0 {
  color: var(--text-dim);
}

.bit-cell.accent2 {
  background: rgba(123, 94, 167, 0.15);
  border-color: rgba(123, 94, 167, 0.45);
  color: #b39ddb;
}

.bit-cell.accent3 {
  background: rgba(0, 255, 157, 0.10);
  border-color: rgba(0, 255, 157, 0.40);
  color: var(--accent3);
}

.bit-cell.warn {
  background: rgba(255, 179, 71, 0.10);
  border-color: rgba(255, 179, 71, 0.40);
  color: var(--accent-warn);
}

.bit-label {
  font-size: 11px;
  color: var(--text-dim);
  font-family: var(--sans);
  margin-right: 6px;
  min-width: 28px;
}

/* ─── RESULT BOX ─── */
.result-box {
  background: linear-gradient(135deg, rgba(0, 212, 255, 0.06), rgba(123, 94, 167, 0.06));
  border: 1px solid rgba(0, 212, 255, 0.3);
  border-radius: var(--radius);
  padding: 24px;
  text-align: center;
  margin-bottom: 24px;
  display: none;
}

.result-box.show {
  display: block;
}

.result-box .result-mode {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 8px;
}

.result-box .result-value {
  font-family: var(--mono);
  font-size: 28px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 6px;
  margin-bottom: 12px;
}

.result-box .result-bits {
  justify-content: center;
}

.result-box .result-bits .bit-cell {
  width: 46px;
  height: 46px;
}

.result-box .result-bits .bit-val {
  font-size: 20px;
}

/* ─── STEPS ─── */
.steps-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  user-select: none;
  padding: 16px 20px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 0;
  transition: border-color 0.2s;
}

.steps-toggle:hover {
  border-color: rgba(0, 212, 255, 0.4);
}

.steps-toggle .toggle-label {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--accent);
}

.steps-toggle .toggle-arrow {
  font-size: 18px;
  color: var(--accent);
  transition: transform 0.3s;
}

.steps-toggle.open .toggle-arrow {
  transform: rotate(180deg);
}

.steps-content {
  display: none;
  border: 1px solid var(--border);
  border-top: none;
  border-radius: 0 0 var(--radius) var(--radius);
  padding: 24px;
  background: var(--bg-panel);
}

.steps-content.open {
  display: block;
}

/* ─── STEP BLOCK ─── */
.step-block {
  margin-bottom: 28px;
  padding-bottom: 28px;
  border-bottom: 1px solid rgba(136, 146, 176, 0.12);
}

.step-block:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.step-title {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--accent2);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 22px;
  height: 22px;
  background: var(--accent2);
  color: #fff;
  border-radius: 50%;
  font-size: 11px;
  font-weight: 700;
  flex-shrink: 0;
}

.step-row {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.step-row-label {
  font-size: 12px;
  color: var(--text-label);
  font-family: var(--sans);
  font-weight: 700;
  min-width: 130px;
  padding-top: 9px;
}

.perm-table {
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
  align-items: center;
}

.perm-cell {
  width: 30px;
  height: 30px;
  background: rgba(0, 212, 255, 0.06);
  border: 1px solid rgba(0, 212, 255, 0.2);
  border-radius: 4px;
  font-family: var(--mono);
  font-size: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
}

.arrow {
  color: var(--text-dim);
  font-size: 18px;
  padding: 0 4px;
}

.inline-mono {
  font-family: var(--mono);
  font-size: 13px;
  color: var(--accent);
  background: rgba(0, 212, 255, 0.08);
  padding: 2px 8px;
  border-radius: 4px;
}

.sbox-table {
  border-collapse: collapse;
  font-family: var(--mono);
  font-size: 13px;
  margin: 6px 0;
}

.sbox-table th,
.sbox-table td {
  padding: 5px 12px;
  border: 1px solid var(--border);
  text-align: center;
}

.sbox-table th {
  background: rgba(0, 212, 255, 0.08);
  color: var(--accent);
  font-size: 11px;
}

.sbox-table td {
  color: var(--text-main);
}

.sbox-table tr.highlight td {
  background: rgba(0, 212, 255, 0.12);
  color: var(--accent);
}

.sbox-table td.highlight-cell {
  background: rgba(0, 255, 157, 0.15);
  color: var(--accent3);
  font-weight: 700;
}

.xor-row {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.xor-op {
  font-family: var(--mono);
  font-size: 20px;
  color: var(--accent-warn);
  font-weight: 700;
}

.section-divider {
  text-align: center;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 2px;
  color: var(--text-dim);
  text-transform: uppercase;
  padding: 12px 0;
  border-top: 1px solid rgba(136, 146, 176, 0.1);
  border-bottom: 1px solid rgba(136, 146, 176, 0.1);
  margin: 20px 0;
}

.phase-header {
  background: linear-gradient(135deg, rgba(123, 94, 167, 0.18), rgba(0, 212, 255, 0.08));
  border-left: 3px solid var(--accent2);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 10px 16px;
  margin-bottom: 18px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: #c5b8f5;
}

/* ─── REFERENCE TABLES ─── */
.ref-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 16px;
  margin-top: 12px;
}

.ref-card {
  background: var(--bg-card2);
  border: 1px solid var(--border2);
  border-radius: var(--radius-sm);
  padding: 14px;
}

.ref-card h4 {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--accent2);
  margin-bottom: 10px;
}

.ref-perm {
  display: flex;
  gap: 5px;
  flex-wrap: wrap;
}

.ref-perm span {
  width: 28px;
  height: 28px;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: 4px;
  font-family: var(--mono);
  font-size: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-label);
}

.no-result {
  color: var(--text-dim);
  font-size: 14px;
  text-align: center;
  padding: 20px 0;
}

/* scrollbar */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: var(--bg-deep);
}

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}