:root {
  --primary-color: #0056ff;
  --secondary-color: #f0f4f8;
  --text-color: #333;
  --white-color: #fff;
  --border-color: #ddd;
  --success-color: #2ecc71;
  --danger-color: #e74c3c;
  --shadow: 0 4px 12px rgba(0,0,0,0.08);
}

body {
  font-family: 'Poppins', sans-serif;
  margin: 0;
  background-color: var(--secondary-color);
  color: var(--text-color);
}

.container { max-width: 900px; margin: auto; padding: 20px; }
header { background: var(--white-color); box-shadow: var(--shadow); padding: 15px 20px; position: sticky; top: 0; z-index: 1000; display: flex; justify-content: space-between; align-items: center; }
.logo { font-weight: 700; font-size: 22px; text-decoration: none; color: var(--primary-color); }
nav a { margin-left: 20px; text-decoration: none; color: var(--primary-color); font-weight: 500; }
.breadcrumb { margin: 15px 0; font-size: 14px; color: #555; }
.tool-box { background: var(--white-color); padding: 30px; border-radius: 12px; box-shadow: var(--shadow); text-align: center; }
.tool-icon { width: 70px; height: 70px; margin-bottom: 15px; }
h1 { font-size: 28px; color: var(--primary-color); margin-top: 0; }
.description { max-width: 650px; margin: 0 auto 25px auto; }

/* Solver Specific Styles */
.solver-container {
  display: flex;
  gap: 10px;
  max-width: 600px;
  margin: 20px auto;
}
#equationInput {
  flex-grow: 1;
  padding: 15px;
  font-size: 18px;
  border: 2px solid var(--border-color);
  border-radius: 8px;
  font-family: 'Courier New', Courier, monospace;
  text-align: center;
  transition: border-color 0.3s, box-shadow 0.3s;
}
#equationInput:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 4px rgba(0, 86, 255, 0.1);
}
.btn-solve {
  background: var(--success-color);
  color: var(--white-color);
  border: none;
  padding: 15px 30px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 18px;
  font-weight: 600;
  transition: background-color 0.3s;
}
.btn-solve:hover {
  background: #27ae60;
}

/* Result Display */
.result-container {
  margin-top: 30px;
  padding: 20px;
  background: var(--secondary-color);
  border-radius: 8px;
  border: 1px dashed var(--border-color);
}
.result-container h2 {
  margin-top: 0;
  font-size: 18px;
  color: var(--text-color);
}
#resultOutput {
  font-size: 36px;
  font-weight: 700;
  color: var(--primary-color);
  margin: 0;
  word-wrap: break-word;
}
#resultOutput.error {
  color: var(--danger-color);
  font-size: 24px;
}

/* General Sections */
section { margin-top: 40px; }
h2 { text-align: center; margin-bottom: 20px; color: var(--primary-color); }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 20px; }
.card { background: var(--white-color); padding: 20px; border-radius: 10px; box-shadow: var(--shadow); text-align: center; }
.card img { width: 50px; height: 50px; margin-bottom: 10px; }
.card button { background: var(--primary-color); color: var(--white-color); border: none; padding: 10px 20px; border-radius: 6px; cursor: pointer; }
.faq-item { background: var(--white-color); padding: 15px 20px; border-radius: 8px; margin-bottom: 10px; box-shadow: var(--shadow); }
footer { text-align: center; padding: 20px; background: var(--white-color); margin-top: 40px; border-top: 1px solid var(--border-color); }
#backToTop { position: fixed; bottom: 20px; right: 20px; background: var(--primary-color); color: var(--white-color); border: none; border-radius: 50%; width: 45px; height: 45px; cursor: pointer; display: none; font-size: 20px; }
/* style.css */

/* --- Global Styles & Variables --- */
:root {
  --primary: #0056ff;
  --secondary: linear-gradient(135deg, #00E0FF, #00FFFF); /* Bright Cyan Gradient */
  --text: #222;
}

body {
  font-family: Poppins, sans-serif;
  margin: 0;
  background: var(--secondary);
  color: var(--text);
}

.container {
  max-width: 1200px;
  margin: auto;
  padding: 20px;
}

/* --- Header Styles --- */
header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: linear-gradient(90deg, #0056ff, #00aaff);
  padding: 15px 30px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.2);
  border-bottom-left-radius: 12px;
  border-bottom-right-radius: 12px;
}

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

/* Logo */
.logo-link {
  display: flex;
  align-items: center;
  text-decoration: none;
  transition: transform 0.3s ease;
}

.logo-img {
  margin-right: 12px;
  filter: brightness(1) invert(0.9) sepia(0.8) saturate(3) hue-rotate(45deg);
}

.logo-text {
  font-size: 24px;
  color: #fff;
  text-shadow: 1px 1px 5px rgba(0,0,0,0.3);
  font-weight: 700;
}

/* Navbar links */
#navbar {
  display: flex;
  align-items: center;
  gap: 20px;
}

#navbar a {
  color: #fff;
  font-weight: 600;
  font-size: 16px;
  text-decoration: none;
  transition: all 0.3s ease;
  padding: 5px 0;
}

#navbar a:hover {
  color: #fffa;
  transform: scale(1.1);
}

/* Hamburger Icon */
#hamburger {
  display: none;
  flex-direction: column;
  cursor: pointer;
  gap: 5px;
  z-index: 1002;
}

#hamburger span {
  width: 25px;
  height: 3px;
  background: #fff;
  border-radius: 3px;
  transition: all 0.3s ease;
}

/* Dropdown styles */
.dropdown {
  position: relative;
}

.dropbtn {
  background: none;
  border: none;
  color: #fff;
  font-weight: 600;
  cursor: pointer;
  font-size: 16px;
  font-family: Poppins, sans-serif;
}

.dropdown-content {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  background: #0056ff;
  border-radius: 8px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.2);
  min-width: 180px;
  z-index: 999;
  border: 1px solid #004acb;
}

.dropdown-content a {
  display: block;
  padding: 10px 15px;
  color: #ffffff;
  text-decoration: none;
  transition: background-color 0.2s ease;
}

.dropdown-content a:hover {
  background-color: #004acb;
}

.dropdown:hover .dropdown-content {
  display: block;
}

/* --- Mobile Responsive Menu --- */
@media screen and (max-width: 768px) {
  #hamburger {
    display: flex;
  }

  #navbar {
    position: fixed;
    top: 80px;
    right: 15px;
    width: 250px;
    background: linear-gradient(180deg, #0056ff, #00399d);
    flex-direction: column;
    align-items: flex-start;
    padding: 10px 0;
    gap: 0;
    box-shadow: -5px 5px 15px rgba(0,0,0,0.25);
    z-index: 1001;
    border-radius: 12px;
    transform: translateX(110%);
    transition: transform 0.3s ease-in-out;
  }

  #navbar.show {
    display: flex;
    transform: translateX(0);
  }

  #navbar a, .dropdown {
    padding: 15px 25px;
    text-align: left;
    width: 100%;
    box-sizing: border-box;
  }

  .dropdown-content {
    position: static;
    display: none;
    background: rgba(0, 0, 0, 0.2);
    box-shadow: none;
    border-radius: 0;
    border: none;
    min-width: 100%;
  }

  .dropdown-content a {
    color: #e0f7ff;
    font-weight: normal;
    padding-left: 40px;
  }

  .dropdown.active .dropdown-content {
    display: block;
  }
}

/* --- Footer Styles --- */
footer a {
  text-decoration: none;
  color: var(--primary);
  margin-right: 15px;
}

footer a:hover {
  color: #0039c1;
}

/* Social media icon hover effect */
.footer-social a:hover {
    transform: scale(1.15);
}