/* ═══════════════════════════════════════════════════════════════════════════
   StegVault — Universal Steganography Toolkit
   Design System & Complete UI Styles
   ═══════════════════════════════════════════════════════════════════════════ */

/* ─── Google Fonts (already linked in HTML) ─────────────────────────────── */
/* Inter, JetBrains Mono */

/* ─── CSS Custom Properties ─────────────────────────────────────────────── */
:root {
  /* Color Palette */
  --clr-bg-base:       hsl(220, 20%, 7%);
  --clr-bg-surface:    hsl(220, 18%, 10%);
  --clr-bg-card:       hsl(220, 16%, 13%);
  --clr-bg-card-hover: hsl(220, 16%, 15%);
  --clr-bg-input:      hsl(220, 18%, 9%);
  --clr-bg-glass:      hsla(220, 20%, 15%, 0.6);

  /* Accent */
  --clr-primary:       hsl(245, 85%, 65%);       /* indigo */
  --clr-primary-light: hsl(245, 85%, 75%);
  --clr-primary-dim:   hsla(245, 85%, 65%, 0.15);
  --clr-secondary:     hsl(190, 90%, 42%);       /* cyan */
  --clr-secondary-light: hsl(190, 90%, 56%);
  --clr-secondary-dim: hsla(190, 90%, 42%, 0.15);

  /* Gradient */
  --grad-primary: linear-gradient(135deg, var(--clr-primary), var(--clr-secondary));
  --grad-primary-soft: linear-gradient(135deg, hsla(245,85%,65%,0.2), hsla(190,90%,42%,0.2));
  --grad-card: linear-gradient(160deg, hsl(220,16%,14%) 0%, hsl(220,18%,11%) 100%);

  /* Semantic Colors */
  --clr-success:  hsl(150, 65%, 45%);
  --clr-warning:  hsl(38, 95%, 55%);
  --clr-danger:   hsl(0, 72%, 58%);
  --clr-info:     hsl(210, 80%, 58%);

  /* Strength Colors */
  --clr-strength-0: hsl(0, 72%, 58%);
  --clr-strength-1: hsl(20, 90%, 55%);
  --clr-strength-2: hsl(38, 95%, 55%);
  --clr-strength-3: hsl(150, 65%, 45%);
  --clr-strength-4: hsl(150, 75%, 38%);

  /* Text */
  --clr-text-primary:   hsl(220, 25%, 95%);
  --clr-text-secondary: hsl(220, 15%, 65%);
  --clr-text-muted:     hsl(220, 12%, 45%);
  --clr-text-link:      var(--clr-primary-light);

  /* Borders */
  --clr-border:       hsla(220, 20%, 25%, 0.6);
  --clr-border-focus: var(--clr-primary);
  --clr-border-hover: hsla(220, 20%, 35%, 0.8);

  /* Shadows */
  --shadow-sm:  0 1px 3px rgba(0,0,0,0.4), 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md:  0 4px 16px rgba(0,0,0,0.4), 0 2px 6px rgba(0,0,0,0.3);
  --shadow-lg:  0 8px 32px rgba(0,0,0,0.5), 0 4px 12px rgba(0,0,0,0.3);
  --shadow-glow-primary: 0 0 24px hsla(245,85%,65%,0.25);
  --shadow-glow-secondary: 0 0 24px hsla(190,90%,42%,0.25);

  /* Spacing */
  --sp-1: 4px;  --sp-2: 8px;  --sp-3: 12px;  --sp-4: 16px;
  --sp-5: 20px; --sp-6: 24px; --sp-7: 28px;  --sp-8: 32px;
  --sp-10: 40px; --sp-12: 48px; --sp-16: 64px;

  /* Typography —— 优先使用系统中文字体，中文界面下观感更好且零外部请求 */
  --font-sans: 'Inter', system-ui, -apple-system, 'Segoe UI', 'PingFang SC',
               'Hiragino Sans GB', 'Microsoft YaHei', '微软雅黑', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, 'Courier New',
               'PingFang SC', 'Microsoft YaHei', monospace;

  /* Border Radius */
  --radius-sm:  6px;
  --radius-md:  10px;
  --radius-lg:  16px;
  --radius-xl:  24px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast:   150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow:   400ms ease;

  /* Layout */
  --max-width: 860px;
  --header-height: 72px;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background-color: var(--clr-bg-base);
  color: var(--clr-text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
  /* Animated background */
  background-image:
    radial-gradient(ellipse 80% 60% at 20% 10%, hsla(245,85%,65%,0.06) 0%, transparent 70%),
    radial-gradient(ellipse 60% 50% at 80% 90%, hsla(190,90%,42%,0.05) 0%, transparent 70%);
}

img, video { max-width: 100%; display: block; }
a { color: var(--clr-text-link); text-decoration: none; }
a:hover { text-decoration: underline; }
button { cursor: pointer; border: none; background: none; font-family: inherit; }
input, textarea, select { font-family: inherit; }

:focus-visible {
  outline: 2px solid var(--clr-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ─── Scrollbar ──────────────────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--clr-bg-surface); }
::-webkit-scrollbar-thumb { background: var(--clr-border); border-radius: var(--radius-full); }
::-webkit-scrollbar-thumb:hover { background: var(--clr-border-hover); }

/* ─── Utility ────────────────────────────────────────────────────────────── */
.hidden { display: none !important; }
.visually-hidden {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}

/* ═══════════════════════════════════ HEADER ══════════════════════════════ */
.app-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: hsla(220, 20%, 7%, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--clr-border);
  height: var(--header-height);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--sp-6);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  text-decoration: none;
  flex-shrink: 0;
}

.logo-icon {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  filter: drop-shadow(0 0 12px hsla(245,85%,65%,0.4));
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.logo-name {
  font-size: 1.15rem;
  font-weight: 800;
  background: var(--grad-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.02em;
}

.logo-sub {
  font-size: 0.68rem;
  color: var(--clr-text-muted);
  font-weight: 400;
  letter-spacing: 0.02em;
}

.header-badges {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  flex-shrink: 0;
}

.badge {
  padding: var(--sp-1) var(--sp-3);
  border-radius: var(--radius-full);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.badge--secure {
  background: hsla(245,85%,65%,0.15);
  border: 1px solid hsla(245,85%,65%,0.3);
  color: var(--clr-primary-light);
}

.badge--local {
  background: hsla(190,90%,42%,0.12);
  border: 1px solid hsla(190,90%,42%,0.25);
  color: var(--clr-secondary-light);
}

/* ═══════════════════════════════════ MAIN ════════════════════════════════ */
.app-main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--sp-8) var(--sp-6) var(--sp-16);
  min-height: calc(100vh - var(--header-height) - 80px);
}

/* ═══════════════════════════════════ TABS ════════════════════════════════ */
.tab-nav {
  display: flex;
  align-items: center;
  gap: 0;
  background: var(--clr-bg-card);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-xl);
  padding: var(--sp-1);
  margin-bottom: var(--sp-8);
  position: relative;
  width: fit-content;
  min-width: 300px;
}

.tab-indicator {
  position: absolute;
  top: var(--sp-1);
  left: var(--sp-1);
  height: calc(100% - var(--sp-2));
  width: calc(50% - var(--sp-1));
  background: var(--grad-primary);
  border-radius: calc(var(--radius-xl) - var(--sp-1));
  transition: transform var(--transition-normal);
  box-shadow: var(--shadow-glow-primary);
  pointer-events: none;
}

.tab-nav[data-active="decrypt"] .tab-indicator {
  transform: translateX(calc(100% + var(--sp-1)));
}

.tab-btn {
  position: relative;
  z-index: 1;
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  padding: var(--sp-3) var(--sp-6);
  border-radius: calc(var(--radius-xl) - var(--sp-1));
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--clr-text-muted);
  transition: color var(--transition-fast);
}

.tab-btn--active,
.tab-btn:hover {
  color: var(--clr-text-primary);
}

.tab-btn--active {
  color: #fff;
}

.tab-icon {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

.tab-panel { display: flex; flex-direction: column; gap: var(--sp-6); }

/* ═══════════════════════════════════ STEP INDICATOR ══════════════════════ */
.step-indicator {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
  margin-bottom: var(--sp-4);
  padding: var(--sp-4) var(--sp-6);
  background: var(--clr-bg-card);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
}

.step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-2);
  cursor: default;
}

.step-dot {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 2px solid var(--clr-border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--clr-text-muted);
  transition: all var(--transition-normal);
  background: var(--clr-bg-surface);
}

.step--active .step-dot {
  border-color: var(--clr-primary);
  background: var(--clr-primary-dim);
  color: var(--clr-primary-light);
  box-shadow: 0 0 16px hsla(245,85%,65%,0.3);
}

.step--complete .step-dot {
  border-color: var(--clr-success);
  background: hsla(150,65%,45%,0.15);
  color: var(--clr-success);
}

.step-label {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--clr-text-muted);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.step--active .step-label { color: var(--clr-primary-light); }
.step--complete .step-label { color: var(--clr-success); }

.step-connector {
  flex: 1;
  height: 2px;
  background: var(--clr-border);
  margin: 0 var(--sp-2);
  margin-bottom: var(--sp-5);
  border-radius: var(--radius-full);
  min-width: 32px;
  transition: background var(--transition-normal);
}

.step-connector--complete { background: var(--clr-primary); }

/* ═══════════════════════════════════ CARDS ═══════════════════════════════ */
.card {
  background: var(--grad-card);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: var(--sp-6) var(--sp-8);
  box-shadow: var(--shadow-md);
  transition: border-color var(--transition-normal), box-shadow var(--transition-normal);
}

.card:hover {
  border-color: var(--clr-border-hover);
}

.card-header {
  margin-bottom: var(--sp-6);
}

.card-title-group {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  margin-bottom: var(--sp-1);
}

.step-badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 700;
  padding: 2px var(--sp-2);
  background: var(--grad-primary);
  border-radius: var(--sp-1);
  color: #fff;
  letter-spacing: 0.05em;
}

.card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--clr-text-primary);
  letter-spacing: -0.01em;
}

.card-subtitle {
  font-size: 0.85rem;
  color: var(--clr-text-secondary);
  margin-left: calc(var(--sp-3) + 34px);
  /* indent to align with title past badge */
}

/* ═══════════════════════════════════ CARRIER TYPE TOGGLE ═════════════════ */
.carrier-type-toggle,
.mode-toggle {
  display: flex;
  gap: var(--sp-2);
  margin-bottom: var(--sp-5);
}

.type-btn, .mode-btn {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-5);
  border-radius: var(--radius-md);
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--clr-text-secondary);
  background: var(--clr-bg-surface);
  border: 1px solid var(--clr-border);
  transition: all var(--transition-fast);
}

.type-btn svg, .mode-btn svg { width: 16px; height: 16px; }

.type-btn:hover, .mode-btn:hover {
  color: var(--clr-text-primary);
  border-color: var(--clr-border-hover);
  background: var(--clr-bg-card-hover);
}

.type-btn--active, .mode-btn--active {
  background: var(--clr-primary-dim);
  border-color: var(--clr-primary);
  color: var(--clr-primary-light);
  box-shadow: 0 0 12px hsla(245,85%,65%,0.15);
}

/* ═══════════════════════════════════ DROP ZONES ══════════════════════════ */
.drop-zone {
  border: 2px dashed var(--clr-border);
  border-radius: var(--radius-lg);
  padding: var(--sp-10) var(--sp-8);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-normal);
  position: relative;
  background: var(--clr-bg-surface);
  /* Animated border via background clip trick */
  background-image: none;
}

.drop-zone::before {
  content: '';
  position: absolute;
  inset: -2px;
  border-radius: calc(var(--radius-lg) + 2px);
  background: var(--grad-primary);
  opacity: 0;
  transition: opacity var(--transition-normal);
  z-index: -1;
}

.drop-zone:hover, .drop-zone:focus-within {
  border-color: transparent;
  background: var(--clr-primary-dim);
  box-shadow: var(--shadow-glow-primary);
}

.drop-zone:hover::before, .drop-zone:focus-within::before {
  opacity: 0.4;
}

.drop-zone--dragover {
  border-color: transparent !important;
  background: var(--clr-primary-dim) !important;
  box-shadow: var(--shadow-glow-primary) !important;
  transform: scale(1.01);
}

.drop-zone--dragover::before { opacity: 0.5 !important; }

.drop-zone--compact {
  padding: var(--sp-4) var(--sp-6);
  border-radius: var(--radius-md);
}

.drop-zone--loaded {
  border-style: solid;
  border-color: var(--clr-success);
  background: hsla(150,65%,45%,0.05);
  padding: var(--sp-4);
}

.drop-zone-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-4);
  text-align: center;
  pointer-events: none;
}

.drop-zone--compact .drop-zone-content {
  flex-direction: row;
  gap: var(--sp-3);
}

.drop-zone-icon svg {
  width: 56px;
  height: 56px;
}

.drop-zone-text { display: flex; flex-direction: column; gap: var(--sp-1); }

.drop-zone-primary {
  font-size: 1rem;
  font-weight: 600;
  color: var(--clr-text-primary);
}

.drop-zone-secondary {
  font-size: 0.85rem;
  color: var(--clr-text-secondary);
}

.drop-zone-formats {
  font-size: 0.75rem;
  color: var(--clr-text-muted);
  font-family: var(--font-mono);
}

/* ═══════════════════════════════════ CARRIER PREVIEW ═════════════════════ */
.carrier-preview {
  margin-top: var(--sp-5);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--clr-bg-surface);
}

.preview-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--sp-3) var(--sp-5);
  border-bottom: 1px solid var(--clr-border);
  background: hsla(220,18%,10%,0.5);
}

.preview-filename {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--clr-text-primary);
  font-family: var(--font-mono);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.preview-remove-btn {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--clr-text-muted);
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.preview-remove-btn:hover {
  background: hsla(0,72%,58%,0.15);
  color: var(--clr-danger);
}

.preview-remove-btn svg { width: 16px; height: 16px; }

.preview-media-container {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0;
}

.preview-thumb {
  width: 180px;
  height: 140px;
  object-fit: cover;
  border-right: 1px solid var(--clr-border);
  flex-shrink: 0;
  background: var(--clr-bg-base);
}

.preview-video {
  width: 100%;
  max-height: 200px;
  background: #000;
  display: block;
}

.preview-audio {
  width: 100%;
  display: block;
  background: var(--clr-bg-base);
  padding: var(--sp-2);
}

.preview-meta {
  padding: var(--sp-4) var(--sp-5);
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
}

.meta-row {
  display: flex;
  gap: var(--sp-4);
  flex-wrap: wrap;
}

.meta-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.meta-label {
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--clr-text-muted);
}

.meta-value {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--clr-text-primary);
  font-family: var(--font-mono);
}

/* ═══════════════════════════════════ CAPACITY GAUGE ══════════════════════ */
.capacity-section {
  margin-top: var(--sp-5);
  background: var(--clr-bg-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-lg);
  padding: var(--sp-5) var(--sp-6);
}

.capacity-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--sp-4);
  gap: var(--sp-4);
  flex-wrap: wrap;
}

.capacity-title {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--clr-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.capacity-pct {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 800;
  color: var(--clr-primary-light);
}

.capacity-pct--warn { color: var(--clr-warning); }
.capacity-pct--danger { color: var(--clr-danger); }

.capacity-gauge-track {
  width: 100%;
  height: 10px;
  background: var(--clr-bg-card);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: var(--sp-4);
}

.capacity-gauge-fill {
  height: 100%;
  background: var(--grad-primary);
  border-radius: var(--radius-full);
  transition: width var(--transition-slow), background var(--transition-normal);
  box-shadow: 0 0 8px hsla(245,85%,65%,0.5);
}

.capacity-gauge-fill--warn {
  background: linear-gradient(90deg, var(--clr-primary), var(--clr-warning));
}

.capacity-gauge-fill--danger {
  background: linear-gradient(90deg, var(--clr-warning), var(--clr-danger));
  box-shadow: 0 0 8px hsla(0,72%,58%,0.5);
}

.capacity-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-3);
}

.capacity-stat { display: flex; flex-direction: column; gap: 2px; }
.capacity-stat .meta-label { color: var(--clr-text-muted); }
.capacity-stat .meta-value { font-size: 0.9rem; }

.capacity-alert {
  margin-top: var(--sp-4);
  padding: var(--sp-3) var(--sp-4);
  background: hsla(0,72%,58%,0.1);
  border: 1px solid hsla(0,72%,58%,0.3);
  border-radius: var(--radius-md);
  font-size: 0.82rem;
  color: hsl(0,72%,75%);
  line-height: 1.5;
}

/* ═══════════════════════════════════ FORMS ══════════════════════════════ */
.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-5);
}

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

.form-group { display: flex; flex-direction: column; gap: var(--sp-2); }

.form-label {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--clr-text-secondary);
  letter-spacing: 0.01em;
}

.required { color: var(--clr-danger); margin-left: 2px; }

.input-wrapper { position: relative; }

.form-input {
  width: 100%;
  padding: var(--sp-3) var(--sp-4);
  padding-right: 44px;
  background: var(--clr-bg-input);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  color: var(--clr-text-primary);
  font-size: 0.9rem;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  -webkit-appearance: none;
  appearance: none;
}

.form-input::placeholder { color: var(--clr-text-muted); }

.form-input:hover { border-color: var(--clr-border-hover); }

.form-input:focus {
  outline: none;
  border-color: var(--clr-primary);
  box-shadow: 0 0 0 3px var(--clr-primary-dim);
}

.form-input--error { border-color: var(--clr-danger) !important; }
.form-input--success { border-color: var(--clr-success) !important; }

.form-textarea {
  width: 100%;
  padding: var(--sp-3) var(--sp-4);
  background: var(--clr-bg-input);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  color: var(--clr-text-primary);
  font-size: 0.9rem;
  font-family: var(--font-mono);
  line-height: 1.6;
  resize: vertical;
  min-height: 140px;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-textarea::placeholder { color: var(--clr-text-muted); font-family: var(--font-sans); }
.form-textarea:hover { border-color: var(--clr-border-hover); }
.form-textarea:focus { outline: none; border-color: var(--clr-primary); box-shadow: 0 0 0 3px var(--clr-primary-dim); }

.input-toggle-btn {
  position: absolute;
  right: var(--sp-3);
  top: 50%;
  transform: translateY(-50%);
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--clr-text-muted);
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast), background var(--transition-fast);
}

.input-toggle-btn:hover { color: var(--clr-text-primary); background: var(--clr-bg-card-hover); }
.eye-icon { width: 18px; height: 18px; }

.field-feedback {
  font-size: 0.78rem;
  min-height: 18px;
  transition: color var(--transition-fast);
}

.field-feedback--success { color: var(--clr-success); }
.field-feedback--error   { color: var(--clr-danger); }

/* ─── Password Strength Meter ────────────────────────────────────────────── */
.strength-meter {
  display: flex;
  flex-direction: column;
  gap: var(--sp-1);
  margin-top: var(--sp-1);
}

.strength-bar {
  width: 100%;
  height: 4px;
  background: var(--clr-bg-card);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.strength-fill {
  height: 100%;
  width: 0%;
  border-radius: var(--radius-full);
  transition: width var(--transition-normal), background var(--transition-normal);
}

.strength-label {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--clr-text-muted);
  transition: color var(--transition-normal);
}

/* Strength levels via CSS data attributes */
.strength-fill[data-strength="0"] { width: 20%; background: var(--clr-strength-0); }
.strength-fill[data-strength="1"] { width: 40%; background: var(--clr-strength-1); }
.strength-fill[data-strength="2"] { width: 60%; background: var(--clr-strength-2); }
.strength-fill[data-strength="3"] { width: 80%; background: var(--clr-strength-3); }
.strength-fill[data-strength="4"] { width: 100%; background: var(--clr-strength-4); }

/* ─── Text Counters ──────────────────────────────────────────────────────── */
.text-counters {
  display: flex;
  gap: var(--sp-2);
  font-size: 0.75rem;
  color: var(--clr-text-muted);
  font-family: var(--font-mono);
  flex-wrap: wrap;
}

.counter-sep { opacity: 0.4; }

/* ─── Divider ────────────────────────────────────────────────────────────── */
.divider-or {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  margin: var(--sp-5) 0;
  color: var(--clr-text-muted);
  font-size: 0.8rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.divider-or::before, .divider-or::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--clr-border);
}

/* ═══════════════════════════════════ FILE LIST ═══════════════════════════ */
.file-list {
  margin-top: var(--sp-4);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.file-list-header {
  display: grid;
  grid-template-columns: 1fr 80px 80px 100px 40px;
  gap: var(--sp-3);
  padding: var(--sp-2) var(--sp-4);
  background: var(--clr-bg-surface);
  border-bottom: 1px solid var(--clr-border);
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--clr-text-muted);
}

.file-list-item {
  display: grid;
  grid-template-columns: 1fr 80px 80px 100px 40px;
  gap: var(--sp-3);
  padding: var(--sp-3) var(--sp-4);
  align-items: center;
  border-bottom: 1px solid var(--clr-border);
  transition: background var(--transition-fast);
  animation: slideInItem 200ms ease both;
}

@keyframes slideInItem {
  from { opacity: 0; transform: translateY(-8px); }
  to   { opacity: 1; transform: translateY(0); }
}

.file-list-item:last-child { border-bottom: none; }
.file-list-item:hover { background: var(--clr-bg-card-hover); }

.file-item-name {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--clr-text-primary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-family: var(--font-mono);
}

.file-item-ext {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--clr-secondary-light);
  font-weight: 600;
}

.file-item-type {
  font-size: 0.75rem;
  color: var(--clr-text-secondary);
}

.file-item-size {
  font-size: 0.78rem;
  font-family: var(--font-mono);
  color: var(--clr-text-secondary);
}

.file-list-footer {
  display: grid;
  grid-template-columns: 1fr 80px 80px 100px 40px;
  gap: var(--sp-3);
  padding: var(--sp-2) var(--sp-4);
  background: var(--clr-bg-surface);
  border-top: 1px solid var(--clr-border);
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--clr-text-primary);
}

.file-remove-btn {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--clr-text-muted);
  transition: all var(--transition-fast);
}

.file-remove-btn:hover { background: hsla(0,72%,58%,0.15); color: var(--clr-danger); }
.file-remove-btn svg { width: 14px; height: 14px; }

/* ─── Info Banner ────────────────────────────────────────────────────────── */
.info-banner {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-3) var(--sp-4);
  background: hsla(190,90%,42%,0.1);
  border: 1px solid hsla(190,90%,42%,0.25);
  border-radius: var(--radius-md);
  font-size: 0.82rem;
  color: var(--clr-secondary-light);
  margin-top: var(--sp-3);
}

.info-banner svg { width: 16px; height: 16px; flex-shrink: 0; }

/* ═══════════════════════════════════ PREFLIGHT ═══════════════════════════ */
.preflight {
  margin-bottom: var(--sp-5);
  padding: var(--sp-4) var(--sp-5);
  background: var(--clr-bg-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
}

.preflight-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: var(--sp-3);
}

.preflight-item { display: flex; flex-direction: column; gap: 2px; }
.preflight-label { font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--clr-text-muted); font-weight: 600; }
.preflight-value { font-size: 0.88rem; font-weight: 600; color: var(--clr-text-primary); font-family: var(--font-mono); }

/* ═══════════════════════════════════ BUTTONS ════════════════════════════ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-2);
  padding: var(--sp-3) var(--sp-6);
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.01em;
  transition: all var(--transition-fast);
  white-space: nowrap;
  position: relative;
  overflow: hidden;
}

.btn::after {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(255,255,255,0);
  transition: background var(--transition-fast);
}
.btn:hover::after { background: rgba(255,255,255,0.06); }
.btn:active::after { background: rgba(255,255,255,0.12); }

.btn--primary {
  background: var(--grad-primary);
  color: #fff;
  box-shadow: var(--shadow-glow-primary), var(--shadow-sm);
}

.btn--primary:hover {
  box-shadow: 0 0 32px hsla(245,85%,65%,0.4), var(--shadow-md);
  transform: translateY(-1px);
}

.btn--primary:active { transform: translateY(0); }

.btn--primary:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.btn--secondary {
  background: var(--clr-bg-card);
  border: 1px solid var(--clr-border);
  color: var(--clr-text-primary);
}

.btn--secondary:hover { border-color: var(--clr-border-hover); background: var(--clr-bg-card-hover); }

.btn--success {
  background: linear-gradient(135deg, var(--clr-success), hsl(170,60%,38%));
  color: #fff;
  box-shadow: 0 0 20px hsla(150,65%,45%,0.3);
}

.btn--large { padding: var(--sp-4) var(--sp-8); font-size: 1rem; border-radius: var(--radius-lg); }
.btn--full { width: 100%; }
.btn-icon { width: 18px; height: 18px; flex-shrink: 0; }

.link-btn {
  color: var(--clr-primary-light);
  font-size: inherit;
  font-weight: 500;
  text-decoration: underline;
  text-decoration-color: hsla(245,85%,75%,0.4);
  pointer-events: all;
  transition: color var(--transition-fast);
}

.link-btn:hover { color: var(--clr-secondary-light); }

/* ═══════════════════════════════════ VALIDATION ══════════════════════════ */
.validation-messages {
  margin-top: var(--sp-4);
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
}

.validation-msg {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-2);
  padding: var(--sp-3) var(--sp-4);
  border-radius: var(--radius-md);
  font-size: 0.82rem;
  line-height: 1.5;
  animation: fadeInMsg 200ms ease;
}

@keyframes fadeInMsg {
  from { opacity: 0; transform: translateY(-4px); }
  to   { opacity: 1; transform: translateY(0); }
}

.validation-msg--error {
  background: hsla(0,72%,58%,0.1);
  border: 1px solid hsla(0,72%,58%,0.25);
  color: hsl(0,72%,75%);
}

.validation-msg--warn {
  background: hsla(38,95%,55%,0.1);
  border: 1px solid hsla(38,95%,55%,0.25);
  color: hsl(38,95%,70%);
}

.validation-msg--ok {
  background: hsla(150,65%,45%,0.1);
  border: 1px solid hsla(150,65%,45%,0.25);
  color: hsl(150,65%,65%);
}

.validation-msg svg { width: 16px; height: 16px; flex-shrink: 0; margin-top: 1px; }

/* ═══════════════════════════════════ PROGRESS ════════════════════════════ */
.progress-panel {
  border-color: var(--clr-primary-dim);
  box-shadow: var(--shadow-glow-primary), var(--shadow-md);
  animation: panelSlideIn 300ms ease;
}

@keyframes panelSlideIn {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

.progress-header {
  display: flex;
  align-items: center;
  gap: var(--sp-4);
  margin-bottom: var(--sp-5);
}

.progress-spinner svg {
  width: 44px;
  height: 44px;
  animation: spin 1s linear infinite;
  flex-shrink: 0;
}

@keyframes spin { to { transform: rotate(360deg); } }

.progress-info { flex: 1; min-width: 0; }

.progress-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--clr-text-primary);
}

.progress-eta {
  font-size: 0.8rem;
  color: var(--clr-text-secondary);
}

.progress-pct {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 800;
  background: var(--grad-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  flex-shrink: 0;
}

.progress-bar-container { margin-bottom: var(--sp-5); }

.progress-bar-track {
  width: 100%;
  height: 8px;
  background: var(--clr-bg-surface);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  width: 0%;
  background: var(--grad-primary);
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
  box-shadow: 0 0 12px hsla(245,85%,65%,0.5);
  position: relative;
  overflow: hidden;
}

.progress-bar-fill::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent 0%, rgba(255,255,255,0.3) 50%, transparent 100%);
  animation: shimmer 1.5s infinite;
}

@keyframes shimmer {
  from { transform: translateX(-100%); }
  to   { transform: translateX(100%); }
}

.progress-steps {
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
}

.progress-step-item {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  transition: all var(--transition-fast);
}

.progress-step-item--pending { color: var(--clr-text-muted); }
.progress-step-item--active  { color: var(--clr-primary-light); background: var(--clr-primary-dim); }
.progress-step-item--done    { color: var(--clr-success); }

.progress-step-icon { width: 16px; height: 16px; flex-shrink: 0; }
.progress-step-icon--spin { animation: spin 0.8s linear infinite; }

/* ═══════════════════════════════════ RESULT PANEL ════════════════════════ */
.result-panel {
  border-color: var(--clr-success);
  box-shadow: 0 0 32px hsla(150,65%,45%,0.15), var(--shadow-md);
  animation: panelSlideIn 300ms ease;
}

.result-success-header {
  display: flex;
  align-items: center;
  gap: var(--sp-4);
  margin-bottom: var(--sp-6);
  padding-bottom: var(--sp-5);
  border-bottom: 1px solid var(--clr-border);
}

.result-success-icon {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: hsla(150,65%,45%,0.15);
  border: 2px solid var(--clr-success);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--clr-success);
  flex-shrink: 0;
}

.result-success-icon svg { width: 28px; height: 28px; }

.result-success-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--clr-success);
  letter-spacing: -0.01em;
}

.result-success-sub {
  font-size: 0.82rem;
  color: var(--clr-text-secondary);
  margin-top: 2px;
}

.result-previews {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-5);
  margin-bottom: var(--sp-6);
}

@media (max-width: 560px) { .result-previews { grid-template-columns: 1fr; } }

.result-preview-card {
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.result-preview-label {
  padding: var(--sp-2) var(--sp-3);
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--clr-text-muted);
  background: var(--clr-bg-surface);
  border-bottom: 1px solid var(--clr-border);
}

.result-preview-img {
  width: 100%;
  height: 120px;
  object-fit: cover;
  display: block;
}

.result-stats {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: var(--sp-3);
  padding: var(--sp-4) var(--sp-5);
  background: var(--clr-bg-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  margin-bottom: var(--sp-5);
}

.preview-audio {
  width: 100%;
  border-radius: var(--radius-md);
  margin-bottom: var(--sp-2);
}

.preview-document-icon {
  width: 100%;
  height: 120px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--clr-bg-surface);
  border-radius: var(--radius-md);
  margin-bottom: var(--sp-2);
  border: 1px dashed var(--clr-border);
}

.preview-meta {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.result-stat { display: flex; flex-direction: column; gap: 2px; }
.result-stat-label { font-size: 0.68rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: var(--clr-text-muted); }
.result-stat-value { font-size: 0.9rem; font-weight: 700; color: var(--clr-text-primary); font-family: var(--font-mono); }
.result-stat-value--success { color: var(--clr-success); }

.result-actions {
  display: flex;
  gap: var(--sp-3);
  flex-wrap: wrap;
}

/* ─── Decrypt Result ──────────────────────────────────────────────────────── */
.decrypt-payload-preview {
  background: var(--clr-bg-input);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  padding: var(--sp-4);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--clr-text-primary);
  max-height: 240px;
  overflow-y: auto;
  white-space: pre-wrap;
  word-break: break-word;
  margin-bottom: var(--sp-5);
}

.integrity-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-1) var(--sp-3);
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 700;
}

.integrity-badge--ok {
  background: hsla(150,65%,45%,0.15);
  border: 1px solid hsla(150,65%,45%,0.3);
  color: var(--clr-success);
}

.integrity-badge--fail {
  background: hsla(0,72%,58%,0.15);
  border: 1px solid hsla(0,72%,58%,0.3);
  color: var(--clr-danger);
}

/* ═══════════════════════════════════ MODAL ══════════════════════════════ */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--sp-4);
  animation: fadeIn 200ms ease;
}

@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.modal-box {
  background: var(--clr-bg-card);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-xl);
  padding: var(--sp-8);
  max-width: 480px;
  width: 100%;
  box-shadow: var(--shadow-lg);
  animation: slideUp 250ms cubic-bezier(0.34,1.56,0.64,1);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-5);
  text-align: center;
}

@keyframes slideUp { from { transform: translateY(20px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }

.modal-icon {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-icon--error {
  background: hsla(0,72%,58%,0.15);
  border: 2px solid hsla(0,72%,58%,0.4);
  color: var(--clr-danger);
}

.modal-icon--error svg { width: 32px; height: 32px; }

.modal-title {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--clr-text-primary);
}

.modal-body {
  font-size: 0.85rem;
  color: var(--clr-text-secondary);
  line-height: 1.7;
  white-space: pre-line;
  text-align: left;
  width: 100%;
  background: var(--clr-bg-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-md);
  padding: var(--sp-4);
}

.modal-box--large {
  max-width: 700px;
  text-align: left;
  align-items: flex-start;
  max-height: 85vh;
  overflow: hidden;
}

.modal-header-inline {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
}

.modal-close-icon {
  background: none;
  border: none;
  color: var(--clr-text-secondary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0 var(--sp-2);
  line-height: 1;
}

.modal-close-icon:hover {
  color: var(--clr-text-primary);
}

.about-content {
  overflow-y: auto;
  padding-right: var(--sp-4);
  background: transparent;
  border: none;
  white-space: normal;
  max-height: 60vh;
}

.about-content h3 {
  color: var(--clr-text-primary);
  margin-top: var(--sp-6);
  margin-bottom: var(--sp-2);
  font-size: 1.05rem;
}

.about-content h3:first-child {
  margin-top: 0;
}

.about-content p {
  margin-bottom: var(--sp-4);
}

.about-content ul {
  list-style-type: disc;
  padding-left: var(--sp-6);
  margin-bottom: var(--sp-4);
}

.about-content li {
  margin-bottom: var(--sp-2);
}

.about-content strong {
  color: var(--clr-primary);
}

.modal-footer {
  width: 100%;
  display: flex;
  justify-content: flex-end;
  border-top: 1px solid var(--clr-border);
  padding-top: var(--sp-4);
}

.header-btn {
  background: transparent;
  border: 1px solid var(--clr-border);
  color: var(--clr-text-primary);
  border-radius: var(--radius-sm);
  padding: var(--sp-1) var(--sp-3);
  font-family: inherit;
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 150ms ease;
  margin-right: var(--sp-3);
}

.header-btn:hover {
  background: var(--clr-bg-surface);
  border-color: var(--clr-primary);
}

/* ═══════════════════════════════════ TOAST ══════════════════════════════ */
.toast-container {
  position: fixed;
  bottom: var(--sp-6);
  right: var(--sp-6);
  z-index: 1100;
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  pointer-events: none;
}

.toast {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-3);
  padding: var(--sp-4) var(--sp-5);
  border-radius: var(--radius-md);
  background: var(--clr-bg-card);
  border: 1px solid var(--clr-border);
  box-shadow: var(--shadow-lg);
  max-width: 380px;
  pointer-events: all;
  animation: toastIn 300ms cubic-bezier(0.34,1.56,0.64,1);
}

@keyframes toastIn { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }
.toast-out { animation: toastOut 200ms ease forwards; }
@keyframes toastOut { to { transform: translateX(120%); opacity: 0; } }

.toast--success { border-color: hsla(150,65%,45%,0.4); }
.toast--error   { border-color: hsla(0,72%,58%,0.4); }
.toast--info    { border-color: hsla(210,80%,58%,0.4); }

.toast-icon { width: 18px; height: 18px; flex-shrink: 0; margin-top: 1px; }
.toast--success .toast-icon { color: var(--clr-success); }
.toast--error .toast-icon   { color: var(--clr-danger); }
.toast--info .toast-icon    { color: var(--clr-info); }

.toast-content { flex: 1; min-width: 0; }
.toast-title { font-size: 0.85rem; font-weight: 700; color: var(--clr-text-primary); margin-bottom: 2px; }
.toast-message { font-size: 0.78rem; color: var(--clr-text-secondary); }

/* ═══════════════════════════════════ FOOTER ══════════════════════════════ */
.app-footer {
  border-top: 1px solid var(--clr-border);
  padding: var(--sp-5) var(--sp-6);
  background: var(--clr-bg-surface);
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-2);
  text-align: center;
}

.footer-text {
  font-size: 0.82rem;
  color: var(--clr-text-secondary);
}

.footer-meta {
  font-size: 0.72rem;
  color: var(--clr-text-muted);
  font-family: var(--font-mono);
}

/* ═══════════════════════════════════ RESPONSIVE ══════════════════════════ */
@media (max-width: 700px) {
  .app-main { padding: var(--sp-5) var(--sp-4) var(--sp-12); }
  .card { padding: var(--sp-5) var(--sp-5); }
  .header-badges { display: none; }
  .logo-sub { display: none; }
  .file-list-header, .file-list-item, .file-list-footer {
    grid-template-columns: 1fr 70px 80px 36px;
  }
  .file-list-header > *:nth-child(2),
  .file-list-item > *:nth-child(2) { display: none; }
  .capacity-stats { grid-template-columns: repeat(2, 1fr); }
  .tab-nav { min-width: unset; width: 100%; }
  .step-indicator { padding: var(--sp-3) var(--sp-4); gap: 0; }
}

@media (max-width: 460px) {
  .result-previews { grid-template-columns: 1fr; }
  .form-grid { grid-template-columns: 1fr; }
}

/* ═══════════════════════════════════ ANIMATIONS ══════════════════════════ */
@keyframes pulse-glow {
  0%, 100% { box-shadow: 0 0 8px hsla(245,85%,65%,0.2); }
  50% { box-shadow: 0 0 24px hsla(245,85%,65%,0.5); }
}

.btn--primary:not(:disabled) { animation: none; }

/* Loading skeleton shimmer */
.skeleton {
  background: linear-gradient(90deg, var(--clr-bg-card) 25%, var(--clr-bg-card-hover) 50%, var(--clr-bg-card) 75%);
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite;
  border-radius: var(--radius-sm);
}

@keyframes skeleton-shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ═══════════════════════════════════ 解密结果预览 ══════════════════════════ */

/* 媒体容器（视频内嵌播放等） */
.payload-media-box {
  margin-bottom: var(--sp-5);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--clr-bg-input);
  border: 1px solid var(--clr-border);
}

.payload-video {
  display: block;
  width: 100%;
  max-height: 62vh;
  background: #000;
}

.payload-hint {
  padding: var(--sp-3) var(--sp-4);
  font-size: 0.78rem;
  color: var(--clr-text-secondary);
  text-align: center;
  margin: 0;
}

/* 非视频类型：文件信息卡片（不预览，仅下载） */
.payload-file-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-8) var(--sp-5);
  text-align: center;
}

.payload-file-icon {
  width: 48px;
  height: 48px;
  color: var(--clr-primary);
  margin-bottom: var(--sp-2);
}

.payload-file-name {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.95rem;
  color: var(--clr-text-primary);
  word-break: break-all;
}

.payload-file-meta {
  font-size: 0.78rem;
  color: var(--clr-text-secondary);
}

.payload-file-card .payload-hint {
  padding: var(--sp-2) 0 0;
}

/* 载体预览中的文档图标 */
.preview-doc-svg {
  width: 48px;
  height: 48px;
  color: var(--clr-text-secondary);
}

/* ═══════════════════════════════════ 解密步骤清单 ══════════════════════════ */

.progress-step {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  color: var(--clr-text-muted);
  transition: all var(--transition-fast);
}

.progress-step--active {
  color: var(--clr-primary-light);
  background: var(--clr-primary-dim);
}

.progress-step--done {
  color: var(--clr-success);
}

.progress-step-dot {
  width: 8px;
  height: 8px;
  border-radius: var(--radius-full);
  background: currentColor;
  flex-shrink: 0;
  opacity: 0.5;
}

.progress-step--active .progress-step-dot {
  opacity: 1;
  animation: pulse-glow 1.2s ease-in-out infinite;
}

/* ═══════════════════════════════════ 底部免责声明 ══════════════════════════ */

.footer-disclaimer {
  margin-top: var(--sp-3);
  padding: var(--sp-4) var(--sp-5);
  border: 1px solid var(--clr-border);
  border-left: 3px solid var(--clr-warning);
  border-radius: var(--radius-md);
  background: var(--clr-bg-surface);
  text-align: left;
  max-width: 760px;
}

.footer-disclaimer-title {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--clr-warning);
  margin-bottom: var(--sp-2);
  letter-spacing: 0.02em;
}

.footer-disclaimer p {
  font-size: 0.76rem;
  line-height: 1.75;
  color: var(--clr-text-secondary);
  margin-bottom: var(--sp-2);
}

.footer-disclaimer p:last-child {
  margin-bottom: 0;
}

.footer-disclaimer strong {
  color: var(--clr-text-primary);
  font-weight: 600;
}

/* ═══════════════════════════════════ 双步骤指示器微调 ══════════════════════ */

.step-indicator {
  justify-content: center;
}

/* 中文标签不宜使用字距拉伸与全大写 */
.step-label {
  font-size: 0.78rem;
  letter-spacing: 0.01em;
  text-transform: none;
  white-space: nowrap;
}

@media (max-width: 460px) {
  .payload-video { max-height: 46vh; }
  .footer-disclaimer { padding: var(--sp-3) var(--sp-4); }
  .footer-disclaimer p { font-size: 0.72rem; }
}