:root {
  --primary: #2EC4B6;
  --primary-dark: #1A9C8F;
  --primary-light: #F0FBF9;
  --bg: #FAFBFC;
  --text-primary: #2D3436;
  --text-secondary: #7B8D93;
  --border: #E8EDF0;
  --shadow-sm: 0 1px 3px rgba(0,0,0,.04);
  --shadow: 0 2px 12px rgba(0,0,0,.06);
  --shadow-lg: 0 8px 30px rgba(0,0,0,.08);
  --radius: 16px;
  --radius-sm: 10px;
  --success: #36D399;
  --warning: #FBBD23;
  --error: #F87272;
  --tool-text: #F5F7FA;
  --tool-time: #F5F7FA;
  --tool-image: #F5F7FA;
  --tool-calc: #F5F7FA;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text-primary);
  max-width: 480px;
  margin: 0 auto;
  min-height: 100vh;
  position: relative;
  padding-bottom: 72px;
  -webkit-font-smoothing: antialiased;
  line-height: 1.6;
}

/* ── Page transition ── */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}
#app main {
  animation: fadeIn .3s ease-out;
}

/* ── Card ── */
.card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  margin: 10px 16px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow .25s, transform .25s;
}
.card:hover {
  box-shadow: var(--shadow);
}
.card:active {
  transform: scale(.995);
}

/* ── Buttons ── */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 10px 24px; border-radius: var(--radius-sm); font-size: 15px;
  font-weight: 500; cursor: pointer; border: none;
  transition: all .2s cubic-bezier(.4,0,.2,1);
  letter-spacing: .01em;
}
.btn-primary { background: var(--primary); color: #fff; box-shadow: 0 2px 8px rgba(46,196,182,.25); }
.btn-primary:hover { background: var(--primary-dark); box-shadow: 0 4px 14px rgba(46,196,182,.35); transform: translateY(-1px); }
.btn-primary:active { transform: scale(.97); }
.btn-outline { background: #fff; color: var(--primary); border: 1.5px solid var(--primary); }
.btn-outline:hover { background: var(--primary-light); }
.btn-sm { padding: 6px 14px; font-size: 13px; border-radius: 8px; }

/* ── Input ── */
.input {
  width: 100%; padding: 11px 14px; border: 1.5px solid var(--border);
  border-radius: var(--radius-sm); font-size: 15px; outline: none;
  transition: border-color .25s, box-shadow .25s; background: #fff;
  font-family: inherit;
}
.input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(46,196,182,.1);
}
.input::placeholder { color: #BCC5CA; }

.textarea {
  width: 100%; padding: 11px 14px; border: 1.5px solid var(--border);
  border-radius: var(--radius-sm); font-size: 15px; outline: none;
  resize: vertical; min-height: 80px; font-family: inherit;
  transition: border-color .25s, box-shadow .25s; background: #fff;
}
.textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(46,196,182,.1);
}

.label { font-size: 13px; color: var(--text-secondary); margin-bottom: 4px; display: block; }

/* ── Mood buttons ── */
.mood-btn {
  font-size: 30px; background: #fff; border: 2px solid var(--border);
  border-radius: 14px; padding: 8px 12px; cursor: pointer;
  transition: all .2s cubic-bezier(.4,0,.2,1);
}
.mood-btn:hover { transform: scale(1.08); border-color: var(--primary); }
.mood-btn.active {
  border-color: var(--primary); background: var(--primary-light);
  box-shadow: 0 0 0 3px rgba(46,196,182,.12);
  transform: scale(1.05);
}

/* ── Navigation ── */
.nav-bar {
  position: fixed; bottom: 0; left: 50%; transform: translateX(-50%);
  width: 100%; max-width: 480px;
  background: rgba(255,255,255,.92);
  backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
  border-top: 1px solid var(--border);
  display: flex; justify-content: space-around; padding: 6px 0 2px;
  z-index: 100;
}
.nav-item {
  display: flex; flex-direction: column; align-items: center;
  font-size: 10px; color: var(--text-secondary); cursor: pointer;
  padding: 4px 10px; border: none; background: none;
  transition: color .2s, transform .2s;
}
.nav-item .nav-icon { font-size: 20px; margin-bottom: 1px; transition: transform .2s; }
.nav-item.active { color: var(--primary); }
.nav-item.active .nav-icon { transform: translateY(-2px); }
.nav-item:active { transform: scale(.9); }

/* ── Page Slogan ── */
.page-slogan {
  text-align: center; padding: 20px 16px 4px;
}
.slogan-main {
  font-size: 17px; font-weight: 600; color: var(--text-primary);
  letter-spacing: .02em;
}
.slogan-sub {
  font-size: 13px; color: var(--text-secondary);
  margin-top: 4px; letter-spacing: .03em;
}

/* ── Header bar ── */
.header-bar {
  display: flex; justify-content: space-between; align-items: center;
  padding: 14px 18px; background: rgba(255,255,255,.85);
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.app-logo { font-size: 18px; font-weight: 700; color: var(--primary); letter-spacing: .02em; }

/* ── Auth pages ── */
.auth-page {
  display: flex; flex-direction: column; justify-content: center;
  min-height: 100vh; padding: 40px 24px;
}
.auth-title {
  font-size: 28px; font-weight: 700; color: var(--primary);
  text-align: center; margin-bottom: 8px; letter-spacing: .04em;
}
.auth-subtitle {
  text-align: center; font-size: 14px; color: var(--text-secondary);
  margin-bottom: 28px;
}
.auth-switch { text-align: center; margin-top: 16px; font-size: 14px; color: var(--text-secondary); }
.auth-switch a { color: var(--primary); cursor: pointer; text-decoration: none; font-weight: 500; }

/* ── Mood ── */
.mood-options { display: flex; gap: 8px; flex-wrap: nowrap; justify-content: center; }

/* ── Todo ── */
.todo-item {
  display: flex; align-items: center; gap: 10px; padding: 12px 0;
  border-bottom: 1px solid var(--border);
}
.todo-item:last-child { border-bottom: none; }
.todo-check {
  width: 22px; height: 22px; border-radius: 50%; border: 2px solid #DDE2E5;
  cursor: pointer; flex-shrink: 0; display: flex; align-items: center; justify-content: center;
  transition: all .2s;
}
.todo-check:hover { border-color: var(--primary); }
.todo-check.done { background: var(--success); border-color: var(--success); }
.todo-check.done::after { content: "✓"; color: #fff; font-size: 13px; }
.todo-text { flex: 1; font-size: 15px; }
.todo-text.done { text-decoration: line-through; color: var(--text-secondary); }

/* ── Empty state ── */
.empty-state { text-align: center; padding: 40px 20px; color: var(--text-secondary); }
.empty-icon { font-size: 48px; margin-bottom: 12px; opacity: .7; }

/* ── Toast ── */
.toast {
  position: fixed; top: 20px; left: 50%; transform: translateX(-50%);
  background: var(--text-primary); color: #fff; padding: 10px 24px;
  border-radius: 10px; font-size: 14px; z-index: 300; opacity: 0;
  transition: opacity .3s; box-shadow: var(--shadow-lg);
  pointer-events: none;
}
.toast.show { opacity: 1; }
.toast.error { background: var(--error); }

/* ── Charts ── */
.chart-wrap { position: relative; width: 100%; height: 200px; margin: 0 auto; }
.chart-wrap canvas { width: 100% !important; height: 100% !important; }

/* ── Stats ── */
.stat-row { display: flex; justify-content: space-around; text-align: center; }
.stat-item .stat-val { font-size: 22px; font-weight: 700; color: var(--primary); }
.stat-item .stat-label { font-size: 11px; color: var(--text-secondary); margin-top: 2px; }

/* ── Chips ── */
.k-chip {
  display: inline-block; padding: 5px 14px; border-radius: 14px;
  font-size: 13px; border: 1.5px solid var(--border); background: #fff;
  cursor: pointer; color: var(--text-secondary); flex-shrink: 0;
  transition: all .2s;
}
.k-chip:hover { border-color: var(--primary); color: var(--primary); }
.ktab.active { color: var(--primary) !important; border-bottom-color: var(--primary) !important; }

/* ── Mode switch ── */
.mode-switch { transition: all .25s; }
.mode-switch:hover { opacity: .85; }

/* ── Tools (de-emphasized) ── */
.tools-tabs { display: flex; gap: 6px; padding: 4px 16px 8px; overflow-x: auto; }
.tool-tab {
  padding: 5px 14px; border-radius: 14px; font-size: 12px;
  border: 1.5px solid var(--border); background: #fff; cursor: pointer;
  color: var(--text-secondary); white-space: nowrap; transition: all .2s;
}
.tool-tab:hover { border-color: var(--primary); color: var(--primary); }
.tool-tab.active { background: var(--primary); color: #fff; border-color: var(--primary); }

.tool-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 14px;
  margin: 6px 16px;
  box-shadow: none;
  transition: box-shadow .2s;
}
.tool-card:hover { box-shadow: var(--shadow-sm); }
.tool-card .tool-title {
  font-size: 14px; font-weight: 600; margin-bottom: 10px;
  color: var(--text-primary);
}
.tool-card .input, .tool-card .btn {
  font-size: 13px; padding: 7px 10px;
}

/* ── Feedback page ── */
.feedback-tabs { display: flex; gap: 0; margin: 0 16px; }
.feedback-tab {
  flex: 1; text-align: center; padding: 10px; border: none; background: none;
  font-size: 14px; font-weight: 600; color: var(--text-secondary);
  border-bottom: 2px solid transparent; cursor: pointer; transition: all .2s;
}
.feedback-tab.active { color: var(--primary); border-bottom-color: var(--primary); }

.feedback-item {
  padding: 14px 0; border-bottom: 1px solid var(--border);
}
.feedback-target {
  display: inline-block; margin-top: 6px; padding: 4px 10px;
  background: var(--primary-light); color: var(--primary);
  border-radius: 6px; font-size: 12px; cursor: pointer;
  transition: background .2s;
}
.feedback-target:hover { background: #D4F0EC; }

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 4px; height: 4px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #DDE2E5; border-radius: 2px; }