:root {
  --color-bg: #f5f6f8;
  --color-surface: #ffffff;
  --color-border: #e2e5ea;
  --color-text: #1a1d23;
  --color-text-muted: #6b7280;
  --color-primary: #4f46e5;
  --color-primary-hover: #4338ca;
  --color-primary-soft: #eef2ff;
  --color-success: #16a34a;
  --color-success-soft: #ecfdf3;
  --color-danger: #dc2626;
  --color-danger-soft: #fef2f2;
  --color-warning: #d97706;
  --color-warning-soft: #fffbeb;
  --radius: 10px;
  --shadow: 0 1px 2px rgba(16, 24, 40, .06), 0 1px 3px rgba(16, 24, 40, .08);
  --sidebar-width: 240px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-size: 15px;
  line-height: 1.5;
}

a { color: var(--color-primary); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 { margin: 0 0 .5rem; font-weight: 600; line-height: 1.25; }
p { margin: 0 0 1rem; }

/* Auth pages */
.auth-shell {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem 1rem;
}
.auth-card {
  width: 100%;
  max-width: 400px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 2rem;
}
.auth-card .brand {
  font-weight: 700;
  font-size: 1.4rem;
  color: var(--color-primary);
  margin-bottom: 1.5rem;
  text-align: center;
}
.auth-card h1 { font-size: 1.15rem; text-align: center; }
.auth-foot { text-align: center; margin-top: 1rem; font-size: .9rem; color: var(--color-text-muted); }

/* Forms */
.field { margin-bottom: 1rem; }
.field label { display: block; font-weight: 500; font-size: .875rem; margin-bottom: .35rem; }
.field input, .field select, .field textarea {
  width: 100%;
  padding: .55rem .75rem;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  font-size: .95rem;
  background: var(--color-surface);
  color: var(--color-text);
}
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}
.field .error { color: var(--color-danger); font-size: .8rem; margin-top: .3rem; }
.field-help { font-size: .8rem; color: var(--color-text-muted); margin-top: .3rem; }
.otp-input { letter-spacing: .6rem; font-size: 1.4rem; text-align: center; font-weight: 600; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .4rem;
  padding: .6rem 1.1rem;
  border-radius: 8px;
  border: 1px solid transparent;
  font-size: .9rem;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
}
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--color-primary); color: #fff; }
.btn-primary:hover { background: var(--color-primary-hover); }
.btn-block { width: 100%; }
.btn-secondary { background: var(--color-surface); border-color: var(--color-border); color: var(--color-text); }
.btn-secondary:hover { background: var(--color-bg); }
.btn-sm { padding: .35rem .7rem; font-size: .8rem; }
.btn-danger { background: var(--color-danger); color: #fff; }

.alert { padding: .75rem 1rem; border-radius: 8px; font-size: .875rem; margin-bottom: 1rem; }
.alert-success { background: var(--color-success-soft); color: var(--color-success); }
.alert-danger { background: var(--color-danger-soft); color: var(--color-danger); }
.alert-warning { background: var(--color-warning-soft); color: var(--color-warning); }

/* App shell */
.app-shell { display: flex; min-height: 100vh; }
.sidebar {
  width: var(--sidebar-width);
  background: var(--color-surface);
  border-right: 1px solid var(--color-border);
  padding: 1.25rem 1rem;
  flex-shrink: 0;
}
.sidebar .brand { font-weight: 700; color: var(--color-primary); font-size: 1.2rem; padding: 0 .5rem 1.25rem; }
.sidebar nav a {
  display: block;
  padding: .55rem .65rem;
  border-radius: 8px;
  color: var(--color-text);
  font-size: .9rem;
  font-weight: 500;
  margin-bottom: .15rem;
}
.sidebar nav a:hover { background: var(--color-bg); text-decoration: none; }
.sidebar nav a.active { background: var(--color-primary-soft); color: var(--color-primary); }
.sidebar .divider { height: 1px; background: var(--color-border); margin: 1rem 0; }

.main { flex: 1; min-width: 0; }
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}
.content { padding: 1.5rem; max-width: 1200px; }

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.25rem;
  margin-bottom: 1.25rem;
}
.card h2 { font-size: 1rem; }

.grid { display: grid; gap: 1rem; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr 1fr; } }
@media (max-width: 600px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; } .app-shell { flex-direction: column; } .sidebar { width: 100%; } }

.stat { }
.stat .label { color: var(--color-text-muted); font-size: .8rem; text-transform: uppercase; letter-spacing: .03em; }
.stat .value { font-size: 1.6rem; font-weight: 700; margin-top: .25rem; }

table { width: 100%; border-collapse: collapse; font-size: .875rem; }
th, td { text-align: left; padding: .6rem .5rem; border-bottom: 1px solid var(--color-border); }
th { color: var(--color-text-muted); font-weight: 600; font-size: .78rem; text-transform: uppercase; letter-spacing: .03em; }
tr:last-child td { border-bottom: none; }

.badge { display: inline-block; padding: .15rem .55rem; border-radius: 999px; font-size: .75rem; font-weight: 600; }
.badge-success { background: var(--color-success-soft); color: var(--color-success); }
.badge-warning { background: var(--color-warning-soft); color: var(--color-warning); }
.badge-danger { background: var(--color-danger-soft); color: var(--color-danger); }
.badge-neutral { background: var(--color-bg); color: var(--color-text-muted); }

.kanban { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; }
.kanban-2 { grid-template-columns: repeat(2, 1fr); }
@media (max-width: 900px) { .kanban { grid-template-columns: 1fr; } }
.kanban-col { background: var(--color-bg); border-radius: var(--radius); padding: .75rem; }
.kanban-col h3 { font-size: .85rem; text-transform: uppercase; color: var(--color-text-muted); padding: 0 .25rem; }
.kanban-card { background: var(--color-surface); border: 1px solid var(--color-border); border-radius: 8px; padding: .75rem; margin-bottom: .6rem; box-shadow: var(--shadow); }

.link-box {
  display: flex;
  align-items: center;
  gap: .5rem;
  background: var(--color-primary-soft);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: .75rem 1rem;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: .9rem;
  word-break: break-all;
}

.empty-state { text-align: center; padding: 2.5rem 1rem; color: var(--color-text-muted); }

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #101114;
    --color-surface: #17181c;
    --color-border: #2a2c32;
    --color-text: #e7e8ea;
    --color-text-muted: #9aa0aa;
    --color-primary-soft: #1e1b3f;
    --color-success-soft: #0e2417;
    --color-danger-soft: #2a1414;
    --color-warning-soft: #2a2010;
  }
}