/* ============================================================
   DES Simulator — Stylesheet
   Tema: Dark Cryptography — biru gelap dengan aksen cyan
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;600&family=Inter:wght@300;400;500;600;700&display=swap');

/* ── Reset & Variables ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #0b0e1a;
  --bg-card:   #111828;
  --bg-step:   #161e30;
  --bg-sbox:   #0d1420;
  --border:    #1e2d4a;
  --border-hi: #2a4a7a;
  --cyan:      #00d4ff;
  --cyan-dim:  #005c70;
  --blue:      #3b82f6;
  --blue-dark: #1d3a6e;
  --green:     #10b981;
  --amber:     #f59e0b;
  --red:       #ef4444;
  --text:      #e2e8f0;
  --text-dim:  #8898aa;
  --text-muted:#4a5568;
  --font-mono: 'JetBrains Mono', 'Courier New', monospace;
  --font-ui:   'Inter', system-ui, sans-serif;
  --radius:    8px;
  --radius-lg: 14px;
  --shadow:    0 4px 24px rgba(0,0,0,0.4);
}

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 14px;
  line-height: 1.6;
  min-height: 100vh;
}

/* ── Header ── */
.site-header {
  background: linear-gradient(135deg, #0a0f1e 0%, #0f1829 60%, #0a1428 100%);
  border-bottom: 1px solid var(--border);
  padding: 24px 0 20px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.site-header::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 60% 80% at 50% 0%, rgba(0,212,255,0.06), transparent);
  pointer-events: none;
}

.header-eyebrow {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--cyan);
  margin-bottom: 8px;
}

.header-title {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, #fff 30%, var(--cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 6px;
}

.header-sub {
  font-size: 13px;
  color: var(--text-dim);
  font-weight: 400;
}

/* ── Layout ── */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

.main-wrap {
  display: grid;
  grid-template-columns: 360px 1fr;
  gap: 24px;
  padding: 28px 24px;
  max-width: 1280px;
  margin: 0 auto;
}

/* ── Input Panel ── */
.input-panel {
  position: sticky;
  top: 24px;
  height: fit-content;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.card-header {
  background: linear-gradient(90deg, #0f1e38, #0d1829);
  border-bottom: 1px solid var(--border);
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.card-icon { font-size: 18px; }

.card-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
}

.card-body { padding: 20px; }

/* Form Controls */
.form-group { margin-bottom: 18px; }

.form-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1.2px;
  color: var(--text-dim);
  margin-bottom: 8px;
}

.form-label .toggle-fmt {
  font-size: 10px;
  font-weight: 500;
  color: var(--cyan);
  cursor: pointer;
  text-transform: none;
  letter-spacing: 0;
  background: none;
  border: none;
  padding: 2px 8px;
  border: 1px solid var(--cyan-dim);
  border-radius: 4px;
  transition: background .15s;
}
.form-label .toggle-fmt:hover { background: rgba(0,212,255,0.1); }

.form-input {
  width: 100%;
  background: var(--bg-step);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 13px;
  padding: 10px 12px;
  transition: border-color .2s, box-shadow .2s;
  resize: vertical;
}

.form-input:focus {
  outline: none;
  border-color: var(--cyan);
  box-shadow: 0 0 0 3px rgba(0,212,255,0.12);
}

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

/* Mode Toggle */
.mode-toggle {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-bottom: 20px;
}

.mode-btn {
  padding: 10px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-step);
  color: var(--text-dim);
  font-family: var(--font-ui);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  text-align: center;
  transition: all .2s;
}

.mode-btn:hover { border-color: var(--blue); color: var(--text); }
.mode-btn.encrypt { border-color: var(--cyan); background: rgba(0,212,255,0.08); color: var(--cyan); }
.mode-btn.decrypt { border-color: var(--amber); background: rgba(245,158,11,0.08); color: var(--amber); }

/* Action Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 18px;
  border-radius: var(--radius);
  border: none;
  font-family: var(--font-ui);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all .2s;
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--blue), #2563eb);
  color: #fff;
  box-shadow: 0 2px 12px rgba(59,130,246,0.3);
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 4px 18px rgba(59,130,246,0.4); }

.btn-success {
  background: linear-gradient(135deg, var(--green), #059669);
  color: #fff;
  box-shadow: 0 2px 12px rgba(16,185,129,0.3);
}
.btn-success:hover { transform: translateY(-1px); }

.btn-ghost {
  background: transparent;
  color: var(--text-dim);
  border: 1px solid var(--border);
}
.btn-ghost:hover { color: var(--text); border-color: var(--border-hi); }

.btn-amber {
  background: linear-gradient(135deg, var(--amber), #d97706);
  color: #000;
}

.btn-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 4px;
}

.btn-full { width: 100%; justify-content: center; }

/* ── Error ── */
#error-msg {
  color: var(--red);
  font-size: 12px;
  font-weight: 500;
  min-height: 18px;
  margin: 8px 0 4px;
}

/* ── Output Area ── */
.output-panel { min-width: 0; }

.placeholder-card {
  background: var(--bg-card);
  border: 1px dashed var(--border);
  border-radius: var(--radius-lg);
  padding: 60px;
  text-align: center;
  color: var(--text-muted);
}

.placeholder-icon { font-size: 48px; margin-bottom: 16px; opacity: .4; }
.placeholder-title { font-size: 18px; font-weight: 600; color: var(--text-dim); margin-bottom: 8px; }
.placeholder-text  { font-size: 13px; }

/* ── Summary Card ── */
.summary-card {
  background: linear-gradient(135deg, #0d1829, #0a1628);
  border: 1px solid var(--border-hi);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 20px;
}

.summary-row {
  display: flex;
  align-items: center;
  gap: 16px;
}

.summary-item { flex: 1; }
.summary-item.highlight { padding: 16px; background: rgba(0,212,255,0.06); border-radius: var(--radius); border: 1px solid var(--cyan-dim); }
.summary-label { font-size: 11px; font-weight: 600; text-transform: uppercase; letter-spacing: 1px; color: var(--text-dim); margin-bottom: 6px; }
.summary-hex { font-family: var(--font-mono); font-size: 22px; font-weight: 600; color: var(--cyan); letter-spacing: 2px; margin-bottom: 4px; }
.summary-bin { font-family: var(--font-mono); font-size: 10px; color: var(--text-muted); word-break: break-all; }
.summary-arrow { font-size: 24px; color: var(--text-muted); flex-shrink: 0; }

/* ── Tabs ── */
.tabs {
  display: flex;
  gap: 4px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  padding: 8px 8px 0;
  overflow-x: auto;
}

.tab-btn {
  padding: 10px 20px;
  border: none;
  background: transparent;
  color: var(--text-dim);
  font-family: var(--font-ui);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  border-radius: var(--radius) var(--radius) 0 0;
  border-bottom: 2px solid transparent;
  transition: all .15s;
  white-space: nowrap;
}

.tab-btn:hover { color: var(--text); background: rgba(255,255,255,0.04); }
.tab-btn.active { color: var(--cyan); border-bottom-color: var(--cyan); background: rgba(0,212,255,0.06); }

.tab-pane {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-top: none;
  border-radius: 0 0 var(--radius-lg) var(--radius-lg);
  padding: 24px;
}

/* ── Section ── */
.section-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  margin: 20px 0 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 8px;
}
.section-title:first-child { margin-top: 0; }

/* ── Step Block ── */
.step-block {
  background: var(--bg-step);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  margin-bottom: 12px;
}

.step-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--blue);
  margin-bottom: 10px;
  display: flex;
  align-items: baseline;
  gap: 8px;
  flex-wrap: wrap;
}

.step-note {
  font-size: 11px;
  font-weight: 400;
  color: var(--text-muted);
}

.bit-row {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin: 5px 0;
  flex-wrap: wrap;
}

.bit-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-dim);
  min-width: 140px;
  padding-top: 2px;
  flex-shrink: 0;
}

/* ── Bits Display ── */
.bits {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text);
  display: inline-flex;
  flex-wrap: wrap;
  gap: 3px;
  line-height: 1.4;
}

.bit-group {
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 3px;
  padding: 1px 3px;
  letter-spacing: 1px;
}

.bit { display: inline; }
.bit-hi { color: var(--cyan); font-weight: 700; }
.bit-sep { display: inline-block; width: 4px; }

/* ── XOR Grid ── */
.xor-grid {
  font-family: var(--font-mono);
  font-size: 12px;
  margin: 8px 0;
}

.xor-row {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin: 3px 0;
  flex-wrap: wrap;
}

.xor-lbl {
  min-width: 50px;
  color: var(--text-dim);
  font-size: 11px;
  font-weight: 600;
  padding-top: 2px;
  flex-shrink: 0;
}

.xor-divider {
  height: 1px;
  background: var(--border-hi);
  margin: 6px 0 6px 60px;
}

/* ── S-Box ── */
.sbox-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
  margin: 10px 0;
}

.sbox-cell {
  background: var(--bg-sbox);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px;
  text-align: center;
}

.sbox-title {
  font-size: 11px;
  font-weight: 700;
  color: var(--amber);
  margin-bottom: 6px;
}

.sbox-input {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text-dim);
  background: rgba(255,255,255,0.03);
  border-radius: 3px;
  padding: 2px 4px;
  margin-bottom: 4px;
}

.sbox-info {
  font-size: 10px;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.sbox-value {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--green);
  font-weight: 600;
}

/* ── Round Result ── */
.round-result {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid var(--border);
  font-weight: 600;
}

/* ── Collapsible ── */
.collapsible {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 8px;
  overflow: hidden;
}

.coll-header {
  padding: 12px 16px;
  background: var(--bg-step);
  cursor: pointer;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-dim);
  display: flex;
  align-items: center;
  gap: 8px;
  user-select: none;
  list-style: none;
  transition: background .15s;
}

.coll-header::-webkit-details-marker { display: none; }
.coll-header::before { content: '▶'; font-size: 9px; color: var(--text-muted); transition: transform .2s; flex-shrink: 0; }
details[open] .coll-header::before { transform: rotate(90deg); }
.coll-header:hover { background: rgba(255,255,255,0.04); color: var(--text); }
.coll-header small { color: var(--text-muted); font-size: 11px; }

.coll-body {
  padding: 16px;
  background: var(--bg-card);
  border-top: 1px solid var(--border);
}

/* ── Round Header ── */
.round-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

.round-sub {
  font-size: 12px;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

/* ── Key Schedule Table ── */
.ks-table { width: 100%; border-collapse: collapse; font-size: 12px; }
.ks-table th {
  background: rgba(255,255,255,0.04);
  color: var(--text-dim);
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: .8px;
  padding: 8px 10px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}
.ks-table td {
  padding: 8px 10px;
  border-bottom: 1px solid rgba(255,255,255,0.04);
  font-family: var(--font-mono);
  vertical-align: top;
}
.ks-table tr:hover td { background: rgba(255,255,255,0.02); }

.table-wrap { overflow-x: auto; border-radius: var(--radius); border: 1px solid var(--border); }

/* ── Badge ── */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .5px;
}
.badge-primary { background: rgba(59,130,246,0.2); color: var(--blue); border: 1px solid rgba(59,130,246,0.3); }
.badge-info    { background: rgba(0,212,255,0.1); color: var(--cyan); border: 1px solid var(--cyan-dim); }
.badge-success { background: rgba(16,185,129,0.15); color: var(--green); border: 1px solid rgba(16,185,129,0.3); }

/* ── Result Final ── */
.result-final {
  background: linear-gradient(135deg, rgba(0,212,255,0.06), rgba(0,212,255,0.02));
  border: 1px solid var(--cyan-dim);
  border-radius: var(--radius-lg);
  padding: 24px;
  text-align: center;
  margin-top: 16px;
}

.result-label { font-size: 12px; font-weight: 600; text-transform: uppercase; letter-spacing: 1.5px; color: var(--text-dim); margin-bottom: 8px; }
.result-hex { font-family: var(--font-mono); font-size: 28px; font-weight: 700; color: var(--cyan); letter-spacing: 4px; margin-bottom: 8px; }
.result-bin { font-family: var(--font-mono); font-size: 11px; color: var(--text-muted); word-break: break-all; }

/* ── Footer ── */
.site-footer {
  text-align: center;
  padding: 24px;
  color: var(--text-muted);
  font-size: 12px;
  border-top: 1px solid var(--border);
  margin-top: 48px;
}

/* ── Info Box ── */
.info-box {
  background: rgba(59,130,246,0.07);
  border: 1px solid rgba(59,130,246,0.2);
  border-radius: var(--radius);
  padding: 12px 14px;
  font-size: 12px;
  color: var(--text-dim);
  margin-bottom: 16px;
}

.info-box strong { color: var(--blue); }

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border-hi); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #3a5080; }

/* ── Responsive ── */
@media (max-width: 900px) {
  .main-wrap {
    grid-template-columns: 1fr;
  }
  .input-panel { position: static; }
  .sbox-grid { grid-template-columns: repeat(2, 1fr); }
  .summary-row { flex-direction: column; }
  .summary-arrow { transform: rotate(90deg); }
}

@media (max-width: 600px) {
  .header-title { font-size: 22px; }
  .sbox-grid { grid-template-columns: repeat(2, 1fr); }
  .bit-label { min-width: 100px; }
}

code {
  font-family: var(--font-mono);
  background: rgba(255,255,255,0.06);
  padding: 1px 5px;
  border-radius: 3px;
  font-size: 12px;
}