/* ----- RESET & GLOBAL ----- */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Inter', system-ui, -apple-system, sans-serif;
            background: #f6f8fb;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            color: #1a1e2b;
            line-height: 1.5;
        }

        .app-wrapper {
            max-width: 1200px;
            margin: 0 auto;
            padding: 1.5rem;
            width: 100%;
        }

        /* ----- NAVBAR (with hamburger) ----- */
        .navbar {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 1.2rem 0;
            border-bottom: 1px solid #e9eef5;
            margin-bottom: 2rem;
            flex-wrap: wrap;
            gap: 1rem;
            position: relative;
        }

        .logo a {
            font-weight: 700;
            font-size: 1.8rem;
            letter-spacing: -0.02em;
            background: linear-gradient(135deg, #2563eb, #8b5cf6);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            text-decoration: none;
        }

        .nav-links {
            display: flex;
            gap: 2.2rem;
        }

        .nav-links a {
            text-decoration: none;
            color: #3a4b66;
            font-weight: 500;
            font-size: 1rem;
            transition: color 0.2s;
        }

        .nav-links a:hover {
            color: #2563eb;
        }

        .nav-links a.active {
            color: #2563eb;
            border-bottom: 2px solid #2563eb;
            padding-bottom: 0.25rem;
        }

        /* hamburger */
        .hamburger {
            display: none;
            flex-direction: column;
            cursor: pointer;
            padding: 0.5rem;
        }

        .hamburger span {
            width: 25px;
            height: 2px;
            background: #2c3e5c;
            margin: 3px 0;
            transition: 0.2s;
            border-radius: 2px;
        }

        .mobile-nav {
            display: flex;
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(255,255,255,0.98);
            backdrop-filter: blur(4px);
            z-index: 1000;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            gap: 2rem;
            opacity: 0;
            visibility: hidden;
            transition: opacity 0.2s ease, visibility 0.2s;
        }

        .mobile-nav.active {
            opacity: 1;
            visibility: visible;
        }

        .mobile-nav a {
            font-size: 1.8rem;
            font-weight: 600;
            text-decoration: none;
            color: #0f182a;
        }

        .close-btn {
            position: absolute;
            top: 2rem;
            right: 2rem;
            font-size: 2.5rem;
            cursor: pointer;
            color: #4f658a;
        }

        /* ----- PAGE HEADER & STEP INDICATOR ----- */
        .page-header {
            text-align: center;
            margin-bottom: 2rem;
        }
        .page-header h1 {
            font-size: 2.8rem;
            font-weight: 600;
            letter-spacing: -0.02em;
            color: #0f182a;
            margin-bottom: 0.5rem;
        }
        .page-header p {
            font-size: 1.2rem;
            color: #576e8a;
            max-width: 650px;
            margin: 0 auto;
        }

        .step-indicator {
            display: flex;
            justify-content: center;
            gap: 2rem;
            margin: 2rem 0 3rem;
            font-weight: 500;
        }
        .step {
            display: flex;
            align-items: center;
            gap: 0.5rem;
            color: #9aafc9;
        }
        .step.active {
            color: #2563eb;
            font-weight: 600;
        }
        .step .step-number {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 28px;
            height: 28px;
            border-radius: 50%;
            background: #e9eef5;
            color: #4f658a;
            font-size: 0.9rem;
        }
        .step.active .step-number {
            background: #2563eb;
            color: white;
        }

        /* ----- CARD & SCREEN STYLES ----- */
        .card {
            background: #ffffff;
            border-radius: 28px;
            box-shadow: 0 25px 45px -20px rgba(0,0,0,0.2);
            padding: 2.2rem;
            border: 1px solid rgba(255,255,255,0.6);
            margin-top: 1rem;
        }
        .screen-stack {
            display: grid;
            grid-template-areas: "stack";
        }
        .screen {
            grid-area: stack;
            transition: opacity 0.25s ease-in-out, visibility 0.25s;
        }
        .screen.hidden {
            opacity: 0;
            visibility: hidden;
            pointer-events: none;
        }

        /* ----- SEARCH SECTION ----- */
        .search-section {
            margin: 1rem 0 1.5rem;
        }
        .search-label {
            font-weight: 600;
            font-size: 1.1rem;
            color: #0f182a;
            margin-bottom: 0.75rem;
            display: block;
        }
        .search-wrapper {
            position: relative;
            margin-bottom: 1rem;
        }
        #bookSearch {
            width: 100%;
            padding: 1.2rem 1.5rem;
            font-size: 1.1rem;
            border: 1.5px solid #e2e8f0;
            border-radius: 30px;
            background: white;
            transition: all 0.2s;
        }
        #bookSearch:focus {
            border-color: #8b5cf6;
            box-shadow: 0 0 0 4px rgba(106, 90, 255, 0.15);
            outline: none;
        }
        .popular-searches {
            display: flex;
            gap: 1rem;
            flex-wrap: wrap;
            align-items: center;
            color: #61799e;
            font-size: 0.9rem;
        }
        .popular-searches span {
            background: #edf2fa;
            padding: 0.3rem 1rem;
            border-radius: 30px;
            color: #2c3e5c;
            cursor: default;
        }
        .suggestions {
            position: absolute;
            top: 100%;
            left: 0;
            right: 0;
            background: white;
            border: 1px solid #e9eef5;
            border-radius: 20px;
            box-shadow: 0 20px 35px -12px rgba(0,0,0,0.2);
            max-height: 280px;
            overflow-y: auto;
            z-index: 30;
            margin-top: 6px;
            display: none;
            opacity: 0;
            transition: opacity 0.15s ease;
        }
        .suggestions.show {
            display: block;
            opacity: 1;
        }
        .suggestion-item {
            padding: 0.9rem 1.2rem;
            cursor: pointer;
            font-size: 0.95rem;
            border-bottom: 1px solid #f0f4fc;
        }
        .suggestion-item:hover,
        .suggestion-item.highlighted {
            background: #eef3ff;
        }
        .no-result {
            padding: 0.9rem 1.2rem;
            color: #8a9bb8;
            font-style: italic;
        }

        /* ----- FORM (with validation) ----- */
        .form-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 1.5rem;
            margin: 2rem 0;
        }
        .input-field {
            display: flex;
            flex-direction: column;
        }
        .input-field label {
            font-size: 0.9rem;
            font-weight: 500;
            color: #2c3a50;
            margin-bottom: 0.4rem;
        }
        .input-field input,
        .input-field select {
            font-family: 'Inter', sans-serif;
            font-size: 1rem;
            padding: 0.9rem 1.2rem;
            border: 1.5px solid #e2e8f0;
            border-radius: 18px;
            background: white;
            transition: all 0.2s;
            width: 100%;
        }
        .input-field input:focus,
        .input-field select:focus {
            border-color: #8b5cf6;
            box-shadow: 0 0 0 4px rgba(106, 90, 255, 0.15);
            outline: none;
        }
        select {
            appearance: none;
            background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="%233f5a7c" stroke-width="2"><polyline points="6 9 12 15 18 9"/></svg>');
            background-repeat: no-repeat;
            background-position: right 1.2rem center;
            background-size: 1.2rem;
            padding-right: 2.5rem;
        }

        /* mobile validation feedback */
        .validation-feedback {
            font-size: 0.8rem;
            margin-top: 0.4rem;
            min-height: 1.2rem;
        }
        .validation-feedback.valid {
            color: #0f7b3a;
        }
        .validation-feedback.invalid {
            color: #dc2626;
        }
        .input-field.valid input {
            border-color: #0f7b3a;
            background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="%230f7b3a" stroke-width="3"><polyline points="20 6 9 17 4 12"/></svg>');
            background-repeat: no-repeat;
            background-position: right 1.2rem center;
            background-size: 1.2rem;
        }
        .input-field.invalid input {
            border-color: #dc2626;
        }

        /* trust badges */
        .trust-badges {
            display: flex;
            flex-wrap: wrap;
            gap: 1.5rem;
            justify-content: center;
            margin: 2rem 0 1rem;
            color: #3f5a7c;
        }
        .trust-badges span {
            display: flex;
            align-items: center;
            gap: 0.4rem;
        }

        /* buttons */
        .btn-primary {
            background: linear-gradient(135deg, #3a40da, #b05cff);
            color: white;
            border: none;
            padding: 1rem 2rem;
            border-radius: 50px;
            font-size: 1.2rem;
            font-weight: 600;
            width: 100%;
            cursor: pointer;
            transition: all 0.2s ease;
            box-shadow: 0 12px 22px -10px rgba(90, 75, 255, 0.4);
            margin: 0.8rem 0;
        }
        .btn-primary:not(:disabled):hover {
            transform: translateY(-3px);
            box-shadow: 0 20px 28px -10px #4f46e5;
        }
        .btn-primary:disabled {
            opacity: 0.4;
            cursor: not-allowed;
            background: linear-gradient(135deg, #b2bad1, #c0c9df);
        }

        .btn-secondary {
            background: white;
            color: #2c3e5c;
            border: 1.5px solid #e2e8f0;
            padding: 0.8rem 1.8rem;
            border-radius: 50px;
            font-weight: 500;
            text-decoration: none;
            transition: 0.2s;
            display: inline-block;
        }
        .btn-secondary:hover {
            background: #f8fafd;
            border-color: #cbd5e1;
            transform: translateY(-2px);
        }

        .download-link {
            display: inline-block;
            background: linear-gradient(135deg, #3a40da, #b05cff);
            color: white;
            border: none;
            padding: 1rem 2rem;
            border-radius: 50px;
            font-size: 1.2rem;
            font-weight: 600;
            width: 100%;
            text-align: center;
            text-decoration: none;
            transition: all 0.2s ease;
            box-shadow: 0 12px 22px -10px rgba(90, 75, 255, 0.4);
            margin: 0.8rem 0;
            cursor: pointer;
        }
        .download-link:hover {
            transform: translateY(-3px);
            box-shadow: 0 20px 28px -10px #4f46e5;
        }

        /* download summary */
        .summary-card {
            background: #edf2fa;
            border-radius: 24px;
            padding: 1.5rem;
            margin: 1.8rem 0;
            text-align: left;
        }
        .summary-item {
            display: flex;
            justify-content: space-between;
            padding: 0.5rem 0;
            border-bottom: 1px dashed #d2deed;
        }
        .summary-item:last-child {
            border-bottom: none;
        }
        .summary-label {
            font-weight: 500;
            color: #3a5072;
        }
        .summary-value {
            font-weight: 600;
            color: #11213a;
        }

        /* community section */
        .community-section {
            margin: 1.5rem 0;
            padding-top: 1rem;
            border-top: 1px solid #eef2f6;
        }
        .whatsapp-btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.6rem;
            background: linear-gradient(145deg, #25D366, #128C7E);
            color: white;
            font-weight: 600;
            padding: 0.9rem 1.8rem;
            border-radius: 50px;
            text-decoration: none;
            transition: 0.2s;
            width: 100%;
        }
        .whatsapp-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 14px 24px -8px #128C7E;
        }

        /* share section */
        .share-section {
            background: white;
            border-radius: 28px;
            padding: 2rem;
            text-align: center;
            margin: 2rem 0;
            box-shadow: 0 15px 30px -15px rgba(0,0,0,0.1);
        }
        .share-buttons {
            display: flex;
            gap: 1rem;
            justify-content: center;
            flex-wrap: wrap;
            margin-top: 1.5rem;
        }

        /* footer */
        .footer {
            border-top: 1px solid #e9eef5;
            padding: 2.5rem 0;
            margin-top: 3rem;
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            align-items: center;
            color: #61799e;
            font-size: 0.9rem;
        }
        .footer-links {
            display: flex;
            gap: 2rem;
            flex-wrap: wrap;
        }
        .footer-links a {
            text-decoration: none;
            color: #4d6383;
        }
        .footer-links a:hover {
            color: #2563eb;
        }
        .footer-logo {
            font-weight: 600;
            font-size: 1.2rem;
            background: linear-gradient(135deg, #2563eb, #8b5cf6);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        /* modal */
        .modal-overlay {
            position: fixed;
            top: 0; left: 0; width: 100%; height: 100%;
            background: rgba(0,0,0,0.3);
            backdrop-filter: blur(4px);
            display: flex;
            align-items: center;
            justify-content: center;
            z-index: 1000;
            opacity: 0;
            visibility: hidden;
            transition: 0.2s;
        }
        .modal-overlay.show {
            opacity: 1;
            visibility: visible;
        }
        .modal-card {
            background: white;
            border-radius: 28px;
            padding: 2rem;
            max-width: 440px;
            width: 90%;
        }
        .modal-field {
            margin: 1.5rem 0;
        }
        textarea {
            width: 100%;
            padding: 1rem;
            border: 1.5px solid #e2e8f0;
            border-radius: 18px;
            font-family: 'Inter', sans-serif;
            font-size: 1rem;
            resize: vertical;
            min-height: 120px;
        }
        textarea:focus {
            border-color: #8b5cf6;
            box-shadow: 0 0 0 4px rgba(106, 90, 255, 0.15);
            outline: none;
        }
        .modal-actions {
            display: flex;
            gap: 1rem;
            justify-content: flex-end;
            margin-top: 1.5rem;
        }
        .modal-btn {
            padding: 0.7rem 1.5rem;
            border-radius: 40px;
            font-weight: 500;
            cursor: pointer;
            border: none;
        }
        .modal-btn-primary {
            background: linear-gradient(135deg, #3a40da, #b05cff);
            color: white;
        }
        .modal-btn-secondary {
            background: #eef2f8;
            color: #2f405c;
        }

        /* limit message */
        .limit-message {
            background: #fff3cd;
            border: 1px solid #ffeeba;
            color: #856404;
            padding: 0.8rem;
            border-radius: 16px;
            margin: 1rem 0;
            text-align: center;
            font-size: 0.9rem;
        }

        @media (max-width: 700px) {
            .nav-links { display: none; }
            .hamburger { display: flex; }
            .page-header h1 { font-size: 2rem; }
            .step-indicator { gap: 1rem; flex-wrap: wrap; }
            .trust-badges { flex-direction: column; align-items: center; }
        }