/* Hệ màu Pi Math: navy đậm + cam (theo mẫu tham khảo), nền trắng. */
:root {
  --pm-navy: #13294b;
  --pm-navy-2: #1f3d6e;
  --pm-navy-soft: #eaf0f8;
  --pm-primary: #e8501e;
  --pm-primary-dark: #c8410f;
  --pm-primary-soft: #fdeee7;
  --pm-accent: #13294b;
  --pm-ok: #16a34a;
  --pm-bad: #dc2626;
  --pm-text: #1f2937;
  --pm-muted: #667085;
  --pm-border: #e6e8ee;
  --pm-bg: #f7f8fa;
  --pm-card: #fff;
  --pm-radius: 14px;
}

html { font-size: 15px; }
body {
  font-family: "Be Vietnam Pro", system-ui, sans-serif;
  background: var(--pm-bg);
  color: var(--pm-text);
  min-height: 100vh;
}
small, .small { font-size: 13px; }
a { color: var(--pm-primary); }
a:hover { color: var(--pm-primary-dark); }

/* ---------- Dải navy trên cùng ---------- */
.pm-topbar { background: var(--pm-navy); color: #fff; }
.pm-topbar-inner { max-width: 1280px; margin: 0 auto; padding: 0 20px; height: 40px; display: flex; align-items: center; justify-content: space-between; }
.pm-topbar-tag { font-size: 13px; font-weight: 600; opacity: .85; }
.pm-profile-btn { display: flex; align-items: center; gap: 8px; background: none; border: 0; color: #fff; font-weight: 600; font-size: 14px; padding: 4px 6px; border-radius: 8px; }
.pm-profile-btn:hover { background: rgba(255,255,255,.1); }
.pm-profile-btn .pm-avatar { width: 26px; height: 26px; font-size: 13px; background: var(--pm-primary); }

/* ---------- Thanh menu trắng ---------- */
.pm-nav { background: #fff; border-bottom: 1px solid var(--pm-border); position: sticky; top: 0; z-index: 50; }
.pm-nav-inner { max-width: 1280px; margin: 0 auto; display: flex; align-items: center; gap: 32px; padding: 12px 20px; }
.pm-brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 20px; color: var(--pm-navy); text-decoration: none; letter-spacing: .3px; }
.pm-brand:hover { color: var(--pm-navy); }
.pm-logo { width: 38px; height: 38px; border-radius: 10px; background: var(--pm-navy); color: #fff; display: grid; place-items: center; font-family: Georgia, serif; font-size: 23px; box-shadow: inset 0 -3px 0 var(--pm-primary); }
.pm-nav-links { display: flex; gap: 6px; flex: 1; }
.pm-nav-links a { white-space: nowrap; padding: 8px 12px; color: var(--pm-text); text-decoration: none; font-weight: 500; font-size: 15px; position: relative; }
.pm-nav-links a:hover { color: var(--pm-primary); }
.pm-nav-links a.active { color: var(--pm-primary); }
.pm-nav-links a.active::after { content: ""; position: absolute; left: 12px; right: 12px; bottom: 0; height: 2px; background: var(--pm-primary); border-radius: 2px; }

.pm-avatar { width: 34px; height: 34px; border-radius: 50%; background: var(--pm-navy); color: #fff; display: grid; place-items: center; font-weight: 700; flex-shrink: 0; }
.pm-avatar-lg { width: 42px; height: 42px; font-size: 17px; background: var(--pm-primary); }

/* ---------- Dropdown dùng chung ---------- */
.pm-dd { position: relative; }
.pm-dd-menu {
  display: none; position: absolute; right: 0; top: calc(100% + 8px); min-width: 260px; z-index: 100;
  background: #fff; color: var(--pm-text); border: 1px solid var(--pm-border); border-radius: 14px;
  box-shadow: 0 16px 40px rgba(19, 41, 75, .18); padding: 8px;
}
.pm-dd.open .pm-dd-menu { display: block; }
.pm-dd-head { display: flex; align-items: center; gap: 12px; padding: 10px 10px 12px; border-bottom: 1px solid var(--pm-border); margin-bottom: 6px; }
.pm-dd-head b { display: block; font-size: 15px; }
.pm-dd-head small { color: var(--pm-muted); }
.pm-dd-menu a, .pm-dd-menu button {
  display: block; width: 100%; text-align: left; padding: 10px 12px; border-radius: 10px; border: 0; background: none;
  color: var(--pm-text); text-decoration: none; font-size: 14px; font-weight: 500;
}
.pm-dd-menu a:hover, .pm-dd-menu button:hover { background: var(--pm-primary-soft); color: var(--pm-primary); }
.pm-dd-menu a.active { color: var(--pm-primary); font-weight: 700; background: var(--pm-primary-soft); }
.pm-dd-sep { height: 1px; background: var(--pm-border); margin: 6px 4px; }
.pm-dd-menu form { margin: 0; }

.pm-mobile-dd { display: none; margin-left: auto; }
.pm-nav-toggle { background: #fff; border: 1px solid var(--pm-border); border-radius: 10px; width: 42px; height: 42px; display: grid; place-items: center; }
.pm-burger { display: flex; flex-direction: column; gap: 4px; }
.pm-burger i { display: block; width: 18px; height: 2px; background: var(--pm-navy); border-radius: 2px; transition: transform .2s, opacity .2s; }
.pm-mobile-dd.open .pm-burger i:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.pm-mobile-dd.open .pm-burger i:nth-child(2) { opacity: 0; }
.pm-mobile-dd.open .pm-burger i:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }
.pm-mobile-dd .pm-dd-menu { width: min(320px, calc(100vw - 32px)); }

.pm-table td > a > b, .pm-sticky-col { white-space: nowrap; }

/* ---------- Cài ứng dụng (PWA) ---------- */
.pm-install-btn { display: inline-flex; align-items: center; gap: 8px; background: #fff; color: var(--pm-navy); border: 1px solid #d3dceb; font-weight: 700; white-space: nowrap; }
.pm-install-btn[hidden] { display: none !important; }
.pm-install-btn:hover { background: var(--pm-navy-soft); color: var(--pm-navy); border-color: #c3cfe2; }
.pm-install-btn img { width: 22px; height: 22px; border-radius: 6px; }
.pm-hero .pm-install-btn { margin-top: 14px; border-color: transparent; box-shadow: 0 4px 14px rgba(0, 0, 0, .18); }
.pm-login-install { margin-top: 18px; padding-top: 18px; border-top: 1px solid var(--pm-border); }
.pm-login-install .pm-install-btn { width: 100%; justify-content: center; min-height: 44px; }
.pm-login-install:has(.pm-install-btn[hidden]) { display: none; }
.pm-ios-steps { padding-left: 20px; margin: 0; font-size: 15px; line-height: 1.6; }
.pm-ios-steps li { margin-bottom: 8px; }
.pm-ios-share { display: inline-grid; place-items: center; width: 22px; height: 22px; border: 1.5px solid currentColor; border-radius: 5px; font-size: 12px; }
.pm-ios-icon { width: 22px; height: 22px; border-radius: 5px; vertical-align: -5px; }
.pm-toast { position: fixed; left: 50%; bottom: 24px; transform: translate(-50%, 20px); background: var(--pm-navy); color: #fff; padding: 12px 18px; border-radius: 12px; font-size: 14px; font-weight: 600; box-shadow: 0 10px 30px rgba(0,0,0,.25); opacity: 0; transition: .25s; z-index: 2000; max-width: calc(100vw - 32px); }
.pm-toast.show { opacity: 1; transform: translate(-50%, 0); }

/* Bootstrap: trạng thái bấm/focus theo màu thương hiệu thay cho xanh mặc định. */
.btn-primary:focus, .btn-primary:active, .btn-primary.active { background: var(--pm-primary-dark) !important; border-color: var(--pm-primary-dark) !important; }
.btn:focus-visible { box-shadow: 0 0 0 .2rem rgba(232, 80, 30, .25) !important; }
.form-control:focus, .form-select:focus { border-color: #f3a684; box-shadow: 0 0 0 .2rem rgba(232, 80, 30, .15); }
.form-check-input:checked { background-color: var(--pm-navy); border-color: var(--pm-navy); }
.btn-light { background: #fff; border-color: var(--pm-border); color: var(--pm-navy); }
.btn-light:hover { background: var(--pm-navy-soft); border-color: #d3dceb; color: var(--pm-navy); }

@media (max-width: 860px) {
  .pm-topbar { display: none; }
  .pm-nav-inner { padding: 10px 16px; }
  .pm-nav-links { display: none; }
  .pm-mobile-dd { display: block; }
}