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

body {
    font-family: 'Inter', sans-serif;
    background: #f8fafc;
    color: #0f172a;
    line-height: 1.5;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
header {
    background: white;
    border-bottom: 1px solid #e2e8f0;
    position: sticky;
    top: 0;
    z-index: 10;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(4px);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 24px;
}

.logo a {
    font-size: 1.5rem;
    font-weight: 700;
    text-decoration: none;
    background: linear-gradient(135deg, #3b82f6, #8b5cf6);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

nav ul {
    display: flex;
    gap: 28px;
    list-style: none;
}

nav a {
    text-decoration: none;
    color: #334155;
    font-weight: 500;
    transition: color 0.2s;
}

nav a:hover {
    color: #3b82f6;
}

/* Main content */
main {
    min-height: 70vh;
    padding: 48px 0;
}

/* Tool cards on homepage */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 32px;
    margin-top: 32px;
}

.tool-card {
    background: white;
    border-radius: 24px;
    padding: 28px;
    box-shadow: 0 4px 6px -2px rgba(0,0,0,0.05), 0 1px 2px rgba(0,0,0,0.03);
    transition: transform 0.2s, box-shadow 0.2s;
    text-decoration: none;
    color: inherit;
    border: 1px solid #e2e8f0;
}

.tool-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 25px -12px rgba(0,0,0,0.1);
}

.tool-card h3 {
    font-size: 1.5rem;
    margin-bottom: 12px;
}

.tool-card p {
    color: #475569;
}

/* Calculator page specific */
.calculator-container {
    background: white;
    border-radius: 32px;
    padding: 32px;
    box-shadow: 0 8px 20px rgba(0,0,0,0.05);
    border: 1px solid #e2e8f0;
    max-width: 700px;
    margin: 0 auto 32px;
}

.input-group {
    margin-bottom: 20px;
}

label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    color: #0f172a;
}

input, select {
    width: 100%;
    padding: 12px 16px;
    font-size: 1rem;
    border: 1px solid #cbd5e1;
    border-radius: 16px;
    background: #fefefe;
    transition: border 0.2s;
}

input:focus, select:focus {
    outline: none;
    border-color: #3b82f6;
    box-shadow: 0 0 0 3px rgba(59,130,246,0.2);
}

button {
    background: #3b82f6;
    color: white;
    border: none;
    padding: 12px 24px;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 40px;
    cursor: pointer;
    transition: background 0.2s;
}

button:hover {
    background: #2563eb;
}

.result {
    margin-top: 28px;
    padding: 20px;
    background: #f1f5f9;
    border-radius: 24px;
    font-size: 1.2rem;
    font-weight: 600;
    text-align: center;
    word-break: break-word;
}

.result span {
    color: #3b82f6;
}

.info-text {
    max-width: 700px;
    margin: 0 auto;
    color: #334155;
    background: #f1f5f9;
    padding: 20px;
    border-radius: 24px;
}

/* Footer */
footer {
    text-align: center;
    padding: 32px 0;
    border-top: 1px solid #e2e8f0;
    background: white;
    color: #475569;
    font-size: 0.875rem;
}

footer a {
    color: #3b82f6;
    text-decoration: none;
}

@media (max-width: 720px) {
    .header-container {
        flex-direction: column;
        gap: 12px;
    }
    nav ul {
        gap: 16px;
        flex-wrap: wrap;
        justify-content: center;
    }
    .calculator-container {
        padding: 20px;
    }
}