:root {
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --bg: #f8fafc;
    --text: #0f172a;
    --text-light: #64748b;
    --white: #ffffff;
    --border: #e2e8f0;
    --success: #22c55e;
}

/* FIX 1: 'box-box' galat tha, 'box-sizing' hona chahiye */
* { 
    margin: 0; 
    padding: 0; 
    box-sizing: border-box; 
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; 
}

body { background-color: var(--bg); color: var(--text); line-height: 1.6; -webkit-font-smoothing: antialiased; }

.container { max-width: 1000px; margin: 0 auto; padding: 0 20px; }

/* FIX 2: 'sticky' ke pehle 'position:' likhna zaroori hai */
header { 
    padding: 20px 0; 
    background: var(--white); 
    border-bottom: 1px solid var(--border); 
    position: sticky; 
    top: 0; 
    z-index: 100; 
}

.nav { display: flex; justify-content: space-between; align-items: center; }
.logo { font-size: 1.25rem; font-weight: 800; color: var(--primary); text-decoration: none; display: flex; align-items: center; gap: 8px; }

/* Hero Section */
.hero { padding: 60px 0; text-align: center; }
.hero h1 { font-size: 2.5rem; font-weight: 800; margin-bottom: 16px; letter-spacing: -0.025em; }
/* Mobile par font size chota karne ke liye media query niche hai */

.hero p { color: var(--text-light); font-size: 1.125rem; max-width: 600px; margin: 0 auto 32px; }

/* Dropzone */
.dropzone-container {
    background: var(--white);
    border: 2px dashed var(--border);
    border-radius: 24px;
    padding: 60px 40px;
    text-align: center;
    transition: all 0.2s ease;
    cursor: pointer;
    box-shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
}
.dropzone-container:hover { border-color: var(--primary); background: #f8fafc; transform: scale(1.01); }
.dropzone-icon { font-size: 48px; margin-bottom: 16px; display: block; }

.btn-primary { 
    background: var(--primary); color: white; padding: 14px 36px; 
    border-radius: 12px; font-weight: 600; border: none; cursor: pointer; 
    transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
.btn-primary:hover { background: var(--primary-hover); transform: translateY(-2px); box-shadow: 0 10px 15px -3px rgba(37, 99, 235, 0.3); }

/* Trust Badge */
.trust-badge { 
    display: inline-flex; align-items: center; gap: 6px; background: #ecfdf5; 
    color: #065f46; padding: 8px 20px; border-radius: 100px; font-size: 14px; font-weight: 500; margin-bottom: 24px;
}

/* Filter Options */
.filter-options {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 24px;
    margin: 30px auto;
    max-width: 800px;
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    justify-content: center;
}

.filter-options label {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    padding: 8px 16px;
    border-radius: 8px;
    transition: 0.2s;
}
.filter-options label:hover { background: #f1f5f9; }

input[type="checkbox"] {
    accent-color: var(--primary);
    width: 20px;
    height: 20px;
    cursor: pointer;
}

/* Features */
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 32px; margin-top: 60px; padding-bottom: 80px; }
.feature-card { background: var(--white); padding: 30px; border-radius: 20px; border: 1px solid var(--border); }
.feature-card h3 { margin-bottom: 12px; font-size: 1.2rem; }

/* Responsive Adjustments */
@media (max-width: 768px) {
    .hero h1 { font-size: 1.8rem; }
    .hero { padding: 40px 0; }
    .dropzone-container { padding: 40px 20px; }
}

footer { border-top: 1px solid var(--border); padding: 40px 0; text-align: center; color: var(--text-light); font-size: 14px; }