* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    overflow-x: hidden;
}

/* Animated Background */
.bg-animation {
    position: fixed;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: 0;
    overflow: hidden;
}

.bubble {
    position: absolute;
    bottom: -100px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    animation: rise 15s infinite ease-in;
}

.bubble:nth-child(1) { width: 80px; height: 80px; left: 10%; animation-duration: 12s; }
.bubble:nth-child(2) { width: 60px; height: 60px; left: 20%; animation-duration: 10s; animation-delay: 2s; }
.bubble:nth-child(3) { width: 100px; height: 100px; left: 40%; animation-duration: 14s; animation-delay: 4s; }
.bubble:nth-child(4) { width: 70px; height: 70px; left: 60%; animation-duration: 11s; animation-delay: 1s; }
.bubble:nth-child(5) { width: 90px; height: 90px; left: 75%; animation-duration: 13s; animation-delay: 3s; }
.bubble:nth-child(6) { width: 50px; height: 50px; left: 85%; animation-duration: 9s; animation-delay: 5s; }

@keyframes rise {
    0% {
        bottom: -100px;
        transform: translateX(0);
    }
    50% {
        transform: translateX(100px);
    }
    100% {
        bottom: 110vh;
        transform: translateX(-100px);
    }
}

/* Header */
header {
    position: relative;
    z-index: 10;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    padding: 1.5rem 2rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 2rem;
    font-weight: 800;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: #4a5568;
    font-weight: 600;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: #667eea;
}

/* Hero Section */
.hero {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 4rem 2rem;
    color: white;
}

.hero h1 {
    font-size: 4rem;
    font-weight: 900;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 10px rgba(0, 0, 0, 0.3);
    animation: fadeInDown 1s ease-out;
}

.hero p {
    font-size: 1.5rem;
    opacity: 0.95;
    margin-bottom: 2rem;
    animation: fadeInUp 1s ease-out 0.3s both;
}

@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Main Content */
.container {
    position: relative;
    z-index: 1;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem 4rem;
}

.calculators-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.calc-card {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    padding: 2.5rem;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.15);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    cursor: pointer;
    border: 2px solid transparent;
}

.calc-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    border-color: #667eea;
}

.calc-icon {
    width: 70px;
    height: 70px;
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin-bottom: 1.5rem;
    transition: transform 0.3s;
}

.calc-card:hover .calc-icon {
    transform: rotate(10deg) scale(1.1);
}

.calc-card h3 {
    font-size: 1.5rem;
    color: #2d3748;
    margin-bottom: 0.8rem;
}

.calc-card p {
    color: #718096;
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

.calc-input-group {
    margin: 1rem 0;
}

.calc-input-group label {
    display: block;
    color: #4a5568;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.calc-input-group input {
    width: 100%;
    padding: 0.8rem;
    border: 2px solid #e2e8f0;
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.calc-input-group input:focus {
    outline: none;
    border-color: #667eea;
}

.calc-btn {
    width: 100%;
    padding: 1rem;
    border: none;
    border-radius: 10px;
    font-size: 1.1rem;
    font-weight: 700;
    color: white;
    cursor: pointer;
    transition: all 0.3s;
    margin-top: 1rem;
}

.calc-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.result {
    margin-top: 1.5rem;
    padding: 1.5rem;
    border-radius: 10px;
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    color: white;
    font-size: 1.3rem;
    font-weight: 700;
    text-align: center;
    display: none;
    animation: slideIn 0.5s ease-out;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Color Schemes */
.purple-gradient { background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); }
.blue-gradient { background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%); }
.green-gradient { background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%); }
.orange-gradient { background: linear-gradient(135deg, #fa709a 0%, #fee140 100%); }
.pink-gradient { background: linear-gradient(135deg, #ff9a9e 0%, #fecfef 100%); }
.teal-gradient { background: linear-gradient(135deg, #a8edea 0%, #fed6e3 100%); }

/* Footer */
footer {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 2rem;
    color: white;
    font-size: 0.9rem;
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }

    .hero p {
        font-size: 1.2rem;
    }

    .calculators-grid {
        grid-template-columns: 1fr;
    }

    .nav-links {
        display: none;
    }
}