:root {
  --color-darkblue: #1B325F;
  --color-lightblue: #9CC4E4;
  --color-ultralight: #E9F2F9;
  --color-midblue: #3A89C9;
  --color-orange: #F26C4F;
  --color-textgray: #797979;
  --color-white: #FFFFFF;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Times New Roman', serif;
}

body {
  background-color: var(--color-white);
  color: var(--color-textgray);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
.header {
  background-color: var(--color-darkblue);
  color: var(--color-white);
  padding: 12px 0;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.15);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 40px;
}

.main-name {
  font-size: 26px;
  font-weight: bold;
  color: var(--color-white);
}

/* Head Links */
.head-link {
  display: flex;
  list-style: none;
  flex-wrap: wrap;
}

.head-link li {
  margin-left: 20px;
}

.head-link a {
  color: var(--color-white);
  text-decoration: none;
  font-size: 16px;
  padding: 6px 12px;
  border-radius: 5px;
  transition: background-color 0.3s;
}

.head-link a:hover {
  background-color: var(--color-lightblue);
  color: var(--color-darkblue);
}

/* Navbar */
.navbar {
  background: var(--color-white);
  box-shadow: 0 2px 4px rgba(0,0,0,0.08);
  width: 100%;
}
.nav-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
}
.system-name {
  font-size: 22px;
  font-weight: 800;
  color: var(--color-darkblue);
  margin-right: 40px;
}
.nav-links {
  display: flex;
  gap: 24px;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-links a {
  color: var(--color-darkblue);
  text-decoration: none;
  font-weight: bold;
  padding: 6px 12px;
  border-radius: 6px;
  transition: background 0.2s, color 0.2s;
}
.nav-links a.active,
.nav-links a:hover {
  background: var(--color-lightblue);
  color: var(--color-midblue);
}
.nav-actions {
  display: flex;
  gap: 16px;
}
.nav-btn {
  padding: 6px 18px;
  border-radius: 6px;
  font-weight: bold;
  text-decoration: none;
  font-size: 15px;
  transition: background 0.2s, color 0.2s;
}
.login-btn {
  background: var(--color-midblue);
  color: #fff;
}
.login-btn:hover {
  background: var(--color-darkblue);
  color: #fff;
}
.register-btn {
  background: var(--color-orange);
  color: #fff;
}
.register-btn:hover {
  background: var(--color-darkblue);
  color: #fff;
}
@media (max-width: 900px) {
  .nav-content {
    flex-direction: column;
    gap: 10px;
    padding: 0 10px;
  }
  .nav-links {
    gap: 10px;
  }
  .nav-actions {
    gap: 8px;
  }
}
/* Footer */
.footer {
  background-color: var(--color-darkblue);
  color: var(--color-white);
  padding: 24px 0;
  font-size: 14px;
  margin-top: auto;
}

.foot-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.foot-link {
  display: flex;
  list-style: none;
  justify-content: center;
  margin-bottom: 10px;
  flex-wrap: wrap;
}

.foot-link li {
  margin: 0 10px;
}

.foot-link a {
  color: var(--color-white);
  text-decoration: none;
}

.foot-link a:hover {
  text-decoration: underline;
}

.foot-text {
  font-size: 12px;
  width: 100%;
  text-align: center;
  color: var(--color-lightblue);
}

/* Responsive Design */
@media (max-width: 768px) {
  .navbar {
    flex-direction: column;
    text-align: center;
  }

  .system-name {
    text-align: center;
    width: 100%;
    margin: 10px 0;
  }

  .nav-links {
    justify-content: center;
  }

  .header-content {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    padding: 0 20px;
    text-align: center;
  }

  .head-link {
    flex-wrap: wrap;
    justify-content: flex-start;
  }

  .head-link li {
    margin: 5px;
  }

  .main-name {
    font-size: 22px;
  }

  .login-box {
    width: 90%;
  }

  .foot-link {
    flex-direction: column;
    align-items: center;
  }

  .foot-content {
    padding: 0 10px;
    text-align: center;
  }
}