/* ================================================
   假设法则 — 页面主题
   前缀: as- (assumption)
   ================================================ */

html { scroll-behavior: auto; }

:root {
  --color-primary: #6a5acd;
  --color-primary-light: #8b7fe0;
  --color-primary-dark: #4e3faa;
  --color-primary-glow: rgba(106, 90, 205, 0.10);
  --color-primary-rgb: 106, 90, 205;
}

body {
  min-height: 100vh;
  background:
    radial-gradient(circle at top, hsla(248, 40%, 90%, 0.30), transparent 36%),
    linear-gradient(180deg, hsla(248, 20%, 98%, 1) 0%, hsla(248, 12%, 96%, 1) 100%);
}

/* ================================================
   Layout
   ================================================ */
.as-container {
  max-width: 640px;
  margin: 0 auto;
  padding: calc(60px + var(--space-6)) var(--space-4) var(--space-6);
}

/* ================================================
   Axioms (x₀)
   ================================================ */
.as-axioms {
  margin-bottom: var(--space-8);
}
.as-axiom-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.as-axiom-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}
.as-axiom-item.accepted {
  background: hsla(248, 40%, 96%, 1);
  border-color: var(--color-primary-light);
}
.as-axiom-check {
  flex-shrink: 0;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  border: 2px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 1px;
  transition: border-color 0.2s, background 0.2s;
  font-size: 12px;
  color: transparent;
}
.as-axiom-item.accepted .as-axiom-check {
  border-color: var(--color-primary);
  background: var(--color-primary);
  color: #fff;
}
.as-axiom-text {
  font-size: var(--font-size-body);
  color: var(--color-text);
  line-height: 1.6;
}

/* ================================================
   Assumption Input (x)
   ================================================ */
.as-x-section {
  margin-bottom: var(--space-8);
  opacity: 0.35;
  pointer-events: none;
  transition: opacity 0.4s;
}
.as-x-section.unlocked {
  opacity: 1;
  pointer-events: auto;
}
.as-section-label {
  font-size: var(--font-size-body-sm);
  color: #888;
  margin-bottom: var(--space-2);
}
.as-x-row {
  display: flex;
  gap: var(--space-2);
}
.as-x-input {
  flex: 1;
  padding: var(--space-3) var(--space-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--font-size-body);
  font-family: var(--font-sans);
  background: var(--color-surface);
  color: var(--color-text);
  outline: none;
  transition: border-color 0.2s;
}
.as-x-input:focus {
  border-color: var(--color-primary-light);
}
.as-x-input::placeholder {
  color: #bbb;
}
.as-x-btn {
  flex-shrink: 0;
  padding: 0 var(--space-5);
  border: none;
  border-radius: var(--radius-md);
  background: var(--color-primary);
  color: #fff;
  font-size: var(--font-size-body-sm);
  cursor: pointer;
  transition: background 0.2s;
  min-height: var(--touch-target);
}
.as-x-btn:active { background: var(--color-primary-dark); }

.as-x-pills {
  margin-top: var(--space-2);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}
.as-x-pill {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  border-radius: 100px;
  background: hsla(248, 30%, 94%, 0.6);
  border: 1px solid hsla(248, 20%, 88%, 0.6);
  font-size: var(--font-size-helper);
  color: #777;
  cursor: pointer;
  transition: background 0.2s;
  -webkit-tap-highlight-color: transparent;
  max-width: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.as-x-pill:active { background: hsla(248, 30%, 88%, 0.8); }
.as-x-pill.active {
  background: hsla(248, 40%, 92%, 0.8);
  border-color: var(--color-primary-light);
  color: var(--color-primary-dark);
  cursor: default;
}
.as-x-pill-del {
  font-size: 11px;
  color: #bbb;
  margin-left: 2px;
  cursor: pointer;
  transition: color 0.2s;
}
.as-x-pill-del:hover { color: #888; }

.as-x-expand {
  text-align: center;
  margin-top: var(--space-2);
}
.as-x-expand-btn {
  font-size: var(--font-size-caption);
  color: #aaa;
  cursor: pointer;
  transition: color 0.2s;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}
.as-x-expand-btn:active { color: #888; }
.as-x-expand-btn.open {
  /* arrow flipped via content change in JS */
}

.as-x-all {
  margin-top: var(--space-3);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}
.as-x-all-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: background 0.2s;
}
.as-x-all-item:active { background: #f8f7fc; }
.as-x-all-x {
  flex: 1;
  font-size: var(--font-size-body-sm);
  color: var(--color-text);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.as-x-all-meta {
  flex-shrink: 0;
  font-size: var(--font-size-caption);
  color: #bbb;
}
.as-x-all-del {
  flex-shrink: 0;
  background: none;
  border: none;
  color: #ccc;
  font-size: 13px;
  cursor: pointer;
  padding: 0 2px;
  transition: color 0.2s;
}
.as-x-all-del:hover { color: #999; }

@keyframes as-fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to   { opacity: 1; transform: translateY(0); }
}

.as-y-input-area {
  margin-bottom: var(--space-3);
}
.as-y-prompts {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.as-y-row {
  display: flex;
  gap: var(--space-2);
}
.as-y-input {
  flex: 1;
  padding: var(--space-3) var(--space-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--font-size-body);
  font-family: var(--font-sans);
  background: var(--color-surface);
  color: var(--color-text);
  outline: none;
  transition: border-color 0.2s;
  box-sizing: border-box;
}
.as-y-input:focus {
  border-color: var(--color-primary-light);
}
.as-y-input::placeholder {
  color: #bbb;
}

/* ================================================
   y entries list
   ================================================ */
.as-y-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.as-y-entry {
  display: flex;
  align-items: flex-start;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  animation: as-fadeIn 0.3s ease;
}
.as-y-prefix {
  flex-shrink: 0;
  font-size: var(--font-size-helper);
  color: var(--color-primary);
  font-weight: 500;
  margin-top: 1px;
}
.as-y-text {
  flex: 1;
  font-size: var(--font-size-body);
  color: var(--color-text);
  line-height: 1.6;
}
.as-y-del {
  flex-shrink: 0;
  background: none;
  border: none;
  color: #ccc;
  font-size: 14px;
  cursor: pointer;
  padding: 0 2px;
  line-height: 1;
  transition: color 0.2s;
}
.as-y-del:hover { color: #999; }

/* ================================================
   Action buttons in y space
   ================================================ */
.as-y-actions {
  display: flex;
  justify-content: center;
  gap: var(--space-3);
  flex-wrap: wrap;
  margin-bottom: var(--space-6);
}
.as-y-btn {
  padding: var(--space-3) var(--space-5);
  border-radius: 100px;
  border: 1.5px solid var(--color-border);
  background: var(--color-surface);
  font-size: var(--font-size-body-sm);
  color: var(--color-text);
  cursor: pointer;
  transition: all 0.2s;
  -webkit-tap-highlight-color: transparent;
  min-height: var(--touch-target-sm);
}
.as-y-btn:active { background: #f0eef6; }
.as-y-btn.primary {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}
.as-y-btn.primary:active { background: var(--color-primary-dark); }

.as-rev-card {
  margin-bottom: var(--space-3);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  overflow: hidden;
  animation: as-fadeIn 0.3s ease;
}
.as-rev-card-header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}
.as-rev-card-header:active { background: #f8f7fc; }
.as-rev-card-check {
  flex-shrink: 0;
  color: #5aab78;
  font-size: 0.9rem;
}
.as-rev-card-summary {
  flex: 1;
  min-width: 0;
}
.as-rev-card-old {
  font-size: var(--font-size-helper);
  color: #aaa;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.as-rev-card-old del {
  text-decoration: line-through !important;
  -webkit-text-decoration: line-through;
}
.as-rev-card-new {
  font-size: var(--font-size-helper);
  color: var(--color-primary);
  margin-top: 2px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.as-rev-card-chevron {
  flex-shrink: 0;
  font-size: 12px;
  color: #bbb;
  transition: transform 0.2s;
}
.as-rev-card-chevron.open {
  transform: rotate(180deg);
}
.as-rev-card-body {
  display: none;
  padding: 0 var(--space-4) var(--space-4);
  border-top: 1px solid var(--color-border);
}
.as-rev-card-body.open {
  display: block;
}
.as-rev-card-detail {
  font-size: var(--font-size-helper);
  color: #999;
  line-height: 1.7;
  margin-bottom: var(--space-2);
}
.as-rev-card-detail del {
  text-decoration: line-through !important;
  -webkit-text-decoration: line-through;
  color: #bbb;
}
.as-rev-card-ys {
  margin-top: var(--space-2);
}
.as-rev-card-y {
  font-size: var(--font-size-helper);
  color: var(--color-text);
  line-height: 1.7;
  padding-left: var(--space-3);
}
.as-rev-card-y::before {
  content: '· ';
  color: var(--color-primary-light);
  font-size: var(--font-size-caption);
}

/* (history moved inline to pills area) */

/* ================================================
   Rounds counter
   ================================================ */
.as-round-badge {
  display: inline-block;
  font-size: var(--font-size-caption);
  color: var(--color-primary);
  background: hsla(248, 40%, 96%, 0.8);
  padding: 2px var(--space-2);
  border-radius: 100px;
  margin-left: var(--space-2);
}

/* ================================================
   Reverse assumption (fix old x)
   ================================================ */
.as-reverse {
  /* visible alongside x section */
}
.as-rev-step {
  margin-top: var(--space-4);
}
.as-rev-label {
  font-size: var(--font-size-body-sm);
  color: #999;
  margin-bottom: var(--space-2);
}
.as-rev-row {
  display: flex;
  gap: var(--space-2);
}
.as-rev-input {
  flex: 1;
  padding: var(--space-3) var(--space-4);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: var(--font-size-body);
  font-family: var(--font-sans);
  background: var(--color-surface);
  color: var(--color-text);
  outline: none;
  transition: border-color 0.2s;
  box-sizing: border-box;
}
.as-rev-input:focus {
  border-color: var(--color-primary-light);
}
.as-rev-input::placeholder { color: #bbb; }

.as-rev-result {
  margin-top: var(--space-4);
  animation: as-fadeIn 0.4s ease;
}
.as-rev-old {
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  background: hsla(0, 0%, 96%, 0.8);
  border: 1px solid hsla(0, 0%, 90%, 0.6);
}
.as-rev-crossed {
  font-size: var(--font-size-body-sm);
  color: #aaa;
  line-height: 1.8;
}
.as-rev-crossed del {
  text-decoration: line-through !important;
  color: #bbb;
  -webkit-text-decoration: line-through;
}
.as-rev-tag {
  font-size: var(--font-size-caption);
  color: #ccc;
  margin-right: var(--space-1);
}
.as-rev-arrow {
  text-align: center;
  font-size: 1.2rem;
  color: var(--color-primary-light);
  margin: var(--space-3) 0;
}
.as-rev-new-row {
  display: flex;
  gap: var(--space-2);
  align-items: center;
}
.as-rev-new-label {
  flex-shrink: 0;
  font-size: var(--font-size-body-sm);
  color: var(--color-primary);
  font-weight: 500;
}
.as-rev-x-banner {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  background: hsla(248, 40%, 96%, 0.6);
  border: 1px solid hsla(248, 30%, 88%, 0.5);
}
.as-rev-x-text {
  font-size: var(--font-size-body);
  color: var(--color-primary-dark);
}
.as-rev-resolved {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  background: hsla(140, 30%, 96%, 0.8);
  border: 1px solid hsla(140, 20%, 88%, 0.6);
  margin-top: var(--space-4);
  animation: as-fadeIn 0.4s ease;
}
.as-rev-resolved-check {
  color: #5aab78;
  font-size: 1rem;
  flex-shrink: 0;
}
.as-rev-resolved-text {
  flex: 1;
  font-size: var(--font-size-body-sm);
  color: #aaa;
}
.as-rev-resolved-text del {
  text-decoration: line-through !important;
  -webkit-text-decoration: line-through;
}
.as-rev-resolved-label {
  flex-shrink: 0;
  font-size: var(--font-size-caption);
  color: #5aab78;
}

/* ================================================
   Mobile
   ================================================ */
@media (max-width: 480px) {
  .as-container { padding: calc(60px + var(--space-4)) var(--space-3) var(--space-4); }
  .as-x-row { flex-direction: column; }
  .as-x-btn { min-height: var(--touch-target); }
  .as-rev-new-row { flex-direction: column; }
}