:root {
      --bg: #0b0f0f;
      --card: #0f1414;
      --elev: #0b0f0f;
      --text: #e6f4f1;
      --muted: #a7c7c1;
      --brand: #14b8a6; /* teal-500 */
      --brand-600: #0d9488; /* teal-600 */
      --brand-700: #0f766e; /* teal-700 */
      --ring: rgba(20, 184, 166, 0.35);
      --border: rgba(255,255,255,0.08);
    }
    * { box-sizing: border-box; }
    html, body { height: 100%; }
    body {
      margin: 0; font-family: 'Inter', system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
      color: var(--text); background: radial-gradient(1200px 800px at 20% -10%, rgba(20,184,166,0.15), transparent),
                         radial-gradient(1000px 600px at 120% 10%, rgba(45,212,191,0.12), transparent),
                         var(--bg);
    }
    a { color: inherit; text-decoration: none; }
    .container {
      display: grid; grid-template-columns: 1fr 300px; gap: 28px;
      max-width: 1200px; padding: 24px; margin: 0 auto; align-items: start;
    }

    /* Header */
    header {
      grid-column: 1 / -1; display: flex; align-items: center; justify-content: space-between;
      padding: 8px 0 12px; position: sticky; top: 0; backdrop-filter: blur(6px);
      background: linear-gradient(to bottom, rgba(11,15,15,0.9), rgba(11,15,15,0.65) 60%, transparent);
      z-index: 50;
      border-bottom: 1px solid var(--border);
    }
    .brand {
      display:flex; align-items:center; gap:12px;
    }
    .brand img {
  height: 48px;    /* fix chiều cao */
  width: auto;     /* để tự co theo tỉ lệ */
  object-fit: contain;
  background: none;
  border-radius: 0; /* bỏ bo góc nếu không cần */
}

    .top-actions { display: flex; align-items: center; gap: 10px; }
    .btn {
      display:inline-flex; align-items:center; gap:8px; padding: 10px 14px; border-radius: 14px;
      border: 1px solid var(--border); background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.02));
      box-shadow: 0 0 0 0 transparent; transition: box-shadow .2s ease, transform .12s ease, border-color .2s;
      font-weight: 600; font-size: 0.95rem; color: var(--text);
    }
    .btn:hover { border-color: rgba(255,255,255,0.18); transform: translateY(-1px); }
    .btn.primary { border-color: rgba(20,184,166,0.5); background: linear-gradient(180deg, rgba(20,184,166,0.22), rgba(20,184,166,0.14)); }
    .btn.primary:hover { box-shadow: 0 6px 28px -10px var(--ring); }

    /* Layout: main + right sidebar */
    .main {
      display: grid; gap: 24px;
    }
    .card {
      background: linear-gradient(180deg, rgba(255,255,255,0.03), rgba(255,255,255,0.015));
      border: 1px solid var(--border); border-radius: 18px; padding: 22px; position: relative;
    }
    .card h2 { margin: 0 0 10px; font-size: 1.35rem; }
    .card p { color: var(--muted); line-height: 1.65; }
    .pill { display:inline-block; padding: 6px 10px; border-radius: 999px; font-weight: 600; font-size: 12px; border:1px solid var(--border); color: var(--muted); }

    .hero {
      display:grid; gap: 16px; padding: 24px; border-radius: 22px;
      background: radial-gradient(500px 200px at 15% 0%, rgba(20,184,166,0.22), transparent),
                  linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.02));
      border: 1px solid var(--border);
    }
    .hero h1 { margin: 0; font-size: clamp(1.6rem, 1.1rem + 2.2vw, 2.4rem); letter-spacing: 0.2px; }
    .hero .lead { color: var(--muted); font-size: 1.05rem; line-height: 1.7; }

    /* Burger button */
.menu-toggle {
  display: inline-flex; /* luôn hiện */
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  background: none;
  border: none;
  color: var(--text);
  cursor: pointer;
  padding: 8px 12px;
}

/* Drawer menu */
.menu-drawer {
  position: fixed;
  top: 0; right: 0;
  width: 80%; max-width: 300px;
  height: 100%;
  background: var(--bg);
  border-left: 1px solid var(--border);
  transform: translateX(100%); /* ẩn mặc định */
  transition: transform .3s ease;
  z-index: 100;
  display: grid;
  gap: 12px;
  padding: 20px;
}

.menu-drawer.open {
  transform: translateX(0); /* hiện ra */
}

.menu-drawer a {
  padding: 12px;
  border-radius: 12px;
  font-weight: 600;
  color: var(--text);
  transition: background .2s;
}
.menu-drawer a:hover {
  background: rgba(255,255,255,0.05);
}

.menu-drawer .close {
  justify-self: end;
  font-size: 1.4rem;
  background: none;
  border: none;
  color: var(--muted);
  cursor: pointer;
}


    /* Footer */
    footer {
      border-top: 1px solid var(--border); color: var(--muted); font-size: 0.9rem; padding: 28px 0 46px; grid-column: 1 / -1;
    }

    /* Mobile / Tablet */
    .menu-toggle { display:none; }
    @media (max-width: 980px) {
      .container { grid-template-columns: 1fr; }
      .sidebar { position: static; }
      header { position: sticky; }
      .menu-toggle { display: inline-flex; }
      .menu-drawer {
        position: fixed; inset: 0 0 auto auto; width: 86%; max-width: 360px; height: 100%;
        background: var(--bg); border-left: 1px solid var(--border); transform: translateX(100%);
        transition: transform .25s ease; z-index: 70; padding: 18px; display: grid; gap: 8px; overflow-y:auto;
      }
      .menu-drawer.open { transform: translateX(0); }
      .menu-drawer .close { justify-self: end; }
    }

    /* Utility */
    .muted { color: var(--muted); }
    .row { display: flex; align-items: center; gap: 10px; }
    .spacer { flex: 1; }
    .divider { height:1px; background: var(--border); margin: 14px 0; }
    .kbd { border:1px solid var(--border); padding: 2px 6px; border-radius: 8px; font-weight:600; font-size:12px; color: var(--muted); }

/* Hamburger icon */
.hamburger {
  font-size: 30px;
  cursor: pointer;
  position: fixed;
  top: 20px;
  right: 30px;
  z-index: 1001;
}

/* Sidebar hidden by default */
.sidebar {
  height: 100%;
  width: 0;
  position: fixed;
  top: 0;
  right: 0;
  background-color: #111;
  overflow-x: hidden;
  transition: 0.5s;
  padding-top: 60px;
  z-index: 1000;
}

.sidebar a {
  padding: 12px 24px;
  text-decoration: none;
  font-size: 22px;
  color: #f1f1f1;
  display: block;
  transition: 0.3s;
}

.sidebar a:hover {
  color: #ffcc00;
}

.sidebar .closebtn {
  position: absolute;
  top: 20px;
  right: 25px;
  font-size: 36px;
}