:root {
            /* Color Variables */
            --primary: #FF9933;
            --primary-hover: #F2912B;
            --blue: #87CEEB;
            --dark-slate: #0f172a;
            --slate-600: #475569;
            --slate-400: #94a3b8;
            --bg-start: #f8fafc;
            --bg-end: #e2e8f0;
            --error: #ef4444;
            
            /* Fluid Typography */
            --font-h1: clamp(1.75rem, calc(1.2rem + 2vw), 2.25rem);
            --font-body: clamp(0.95rem, calc(0.8rem + 1vw), 1.05rem);
            --font-small: clamp(0.85rem, calc(0.7rem + 0.5vw), 0.95rem);

            /* Spring Animation */
            --spring: cubic-bezier(0.34, 1.56, 0.64, 1);
            --spring-gentle: cubic-bezier(0.2, 0.8, 0.2, 1);
        }

        * { margin: 0; padding: 0; box-sizing: border-box; }
        
        *:focus-visible {
            outline: 2px solid var(--primary);
            outline-offset: 2px;
        }
        
        body {
            font-family: 'Inter', sans-serif;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
            color: var(--dark-slate);
            line-height: 1.6;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            position: relative;
            background: var(--bg-start);
            overflow-x: hidden;
        }

        /* Animated Mesh Gradient Background */
        .mesh-bg {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100vh;
            z-index: -1;
            background-color: var(--bg-start);
            background-image: 
                radial-gradient(circle at 0% 0%, rgba(255, 153, 51, 0.15) 0px, transparent 50%),
                radial-gradient(circle at 100% 100%, rgba(135, 206, 235, 0.15) 0px, transparent 50%),
                radial-gradient(circle at 100% 0%, rgba(226, 232, 240, 0.8) 0px, transparent 50%);
            animation: meshFloat 15s ease-in-out infinite alternate;
        }

        @keyframes meshFloat {
            0% { background-position: 0% 0%; }
            100% { background-position: 100% 100%; }
        }

        /* Navigation */
        nav {
            position: fixed;
            top: 0;
            width: 100%;
            background: rgba(255, 255, 255, 0.7);
            backdrop-filter: blur(24px);
            -webkit-backdrop-filter: blur(24px);
            border-bottom: 1px solid rgba(255, 255, 255, 0.5);
            z-index: 1000;
            padding-top: env(safe-area-inset-top);
        }

        .nav-container {
            max-width: 1000px;
            margin: 0 auto;
            padding: 1rem 2rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: clamp(1.25rem, 3vw, 1.5rem);
            font-weight: 800;
            letter-spacing: -0.5px;
            text-decoration: none;
            transition: transform 0.4s var(--spring);
        }

        @media (hover: hover) {
            .logo:hover {
                transform: scale(1.05);
            }
        }

        .logo-saffron { color: var(--primary); }
        .logo-blue { color: var(--blue); }

        .back-link {
            text-decoration: none;
            color: var(--slate-600);
            font-weight: 500;
            font-size: var(--font-small);
            transition: all 0.3s var(--spring-gentle);
            display: flex;
            align-items: center;
            gap: 0.5rem;
            padding: 0.75rem 1rem;
            border-radius: 8px;
            min-height: 44px;
        }

        @media (hover: hover) {
            .back-link:hover {
                color: var(--primary);
                background: rgba(255, 153, 51, 0.1);
                transform: translateX(-4px);
            }
        }

        @media (max-width: 480px) {
            .back-link {
                padding: 0.5rem;
            }
            .logo {
                font-size: 1.25rem;
            }
        }

        @media (max-width: 330px) {
            .login-container {
                padding: 5rem 0.25rem 2rem; 
            }
            .login-card {
                padding: 2rem 0.5rem;
            }
            .otp-inputs {
                gap: 0.1rem;
            }
        }

        /* Main Content */
        .login-container {
            flex: 1;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 8rem 2rem 4rem;
        }

        /* Pro Max Glassmorphism Card */
        .login-card {
            background: rgba(255, 255, 255, 0.65);
            backdrop-filter: blur(24px);
            -webkit-backdrop-filter: blur(24px);
            border: 1px solid rgba(255, 255, 255, 0.8);
            padding: 3.5rem;
            border-radius: 28px;
            box-shadow: 
                0 24px 60px rgba(15, 23, 42, 0.08),
                inset 0 2px 4px rgba(255, 255, 255, 0.8);
            width: 100%;
            max-width: 480px;
            animation: cardMount 0.8s var(--spring) forwards;
            position: relative;
            overflow: hidden;
        }

        @keyframes cardMount {
            0% { opacity: 0; transform: translateY(40px) scale(0.95); }
            100% { opacity: 1; transform: translateY(0) scale(1); }
        }

        /* Fluid State Transitions */
        .form-section {
            display: grid;
            grid-template-rows: 0fr;
            transition: grid-template-rows 0.5s var(--spring-gentle);
            opacity: 0;
            visibility: hidden;
        }
        
        .form-section.active {
            grid-template-rows: 1fr;
            opacity: 1;
            visibility: visible;
        }

        .form-inner {
            overflow: hidden;
        }

        .login-header {
            text-align: center;
            margin-bottom: 2.5rem;
        }

        .login-header h1 {
            font-size: var(--font-h1);
            font-weight: 800;
            color: var(--dark-slate);
            margin-bottom: 0.75rem;
            letter-spacing: -0.5px;
        }

        .login-header p {
            color: var(--slate-600);
            font-size: var(--font-body);
        }

        .form-group {
            margin-bottom: 1.5rem;
        }

        .form-label {
            display: block;
            font-weight: 600;
            color: var(--dark-slate);
            margin-bottom: 0.5rem;
            font-size: var(--font-small);
        }

        .input-group {
            display: flex;
            border: 2px solid rgba(226, 232, 240, 0.8);
            border-radius: 16px;
            overflow: hidden;
            transition: all 0.4s var(--spring-gentle);
            background: rgba(248, 250, 252, 0.8);
        }

        .input-group:focus-within {
            border-color: var(--primary);
            background: white;
            box-shadow: 0 0 0 4px rgba(255, 153, 51, 0.15), 0 10px 20px rgba(255, 153, 51, 0.1);
            transform: translateY(-2px);
        }

        .country-code {
            padding: 1rem 1.25rem;
            background: rgba(241, 245, 249, 0.8);
            color: var(--slate-600);
            font-weight: 600;
            border-right: 2px solid rgba(226, 232, 240, 0.8);
            display: flex;
            align-items: center;
        }

        .form-input {
            width: 100%;
            padding: 1rem;
            border: none;
            background: transparent;
            font-size: 16px; /* Prevents iOS Zoom */
            color: var(--dark-slate);
            font-family: inherit;
            outline: none;
        }

        .form-input::placeholder {
            color: var(--slate-400);
        }

        .btn-primary {
            width: 100%;
            background: var(--primary);
            /* WCAG AAA Contrast Fix: Dark text on Saffron background */
            color: var(--dark-slate); 
            padding: 1.1rem 1.5rem;
            border-radius: 16px;
            border: none;
            font-weight: 800;
            font-size: 1.1rem;
            cursor: pointer;
            transition: all 0.5s var(--spring);
            margin-top: 1rem;
            font-family: inherit;
            position: relative;
            overflow: hidden;
            min-height: 44px;
        }

        /* Pro Max Glow Effect */
        .btn-primary::before {
            content: '';
            position: absolute;
            top: 50%;
            left: 50%;
            width: 0;
            height: 0;
            background: radial-gradient(circle, rgba(255, 255, 255, 0.8) 0%, rgba(255, 255, 255, 0) 70%);
            transform: translate(-50%, -50%);
            border-radius: 50%;
            opacity: 0;
            transition: width 0.4s ease, height 0.4s ease, opacity 0.4s ease;
            pointer-events: none;
        }

        @media (hover: hover) {
            .btn-primary:hover:not(:disabled) {
                background: var(--primary-hover);
                transform: translateY(-4px) scale(1.02);
                box-shadow: 0 12px 24px rgba(255, 153, 51, 0.3);
            }
            .btn-primary:hover:not(:disabled)::before {
                width: 300px;
                height: 300px;
                opacity: 0.3;
            }
        }

        .btn-primary:active:not(:disabled) {
            transform: translateY(0) scale(0.98);
        }

        .btn-primary:disabled {
            background: #cbd5e1;
            color: var(--slate-600);
            cursor: not-allowed;
            opacity: 0.7;
        }

        /* OTP Section - Staggered Reveals */
        .otp-inputs {
            display: flex;
            gap: clamp(0.25rem, 1.5vw, 0.75rem);
            justify-content: center;
            margin-bottom: 2rem;
        }

        .otp-input {
            width: clamp(40px, 12vw, 55px);
            height: clamp(50px, 15vw, 65px);
            border: 2px solid rgba(226, 232, 240, 0.8);
            border-radius: 16px;
            font-size: clamp(1.25rem, 4vw, 1.75rem);
            font-weight: 700;
            text-align: center;
            color: var(--dark-slate);
            background: rgba(248, 250, 252, 0.8);
            transition: all 0.4s var(--spring-gentle);
            opacity: 0;
            transform: translateY(10px);
        }

        .form-section.active .otp-input {
            animation: staggerUp 0.6s var(--spring) forwards;
        }

        .form-section.active .otp-input:nth-child(1) { animation-delay: 100ms; }
        .form-section.active .otp-input:nth-child(2) { animation-delay: 150ms; }
        .form-section.active .otp-input:nth-child(3) { animation-delay: 200ms; }
        .form-section.active .otp-input:nth-child(4) { animation-delay: 250ms; }
        .form-section.active .otp-input:nth-child(5) { animation-delay: 300ms; }
        .form-section.active .otp-input:nth-child(6) { animation-delay: 350ms; }

        @keyframes staggerUp {
            to { opacity: 1; transform: translateY(0); }
        }

        /* Error States */
        .error-text {
            color: var(--error);
            font-size: var(--font-small);
            font-weight: 500;
            text-align: center;
            margin-top: 0.75rem;
            min-height: 20px;
            opacity: 0;
            transition: opacity 0.3s;
        }

        .error-text.show {
            opacity: 1;
        }

        .input-error {
            border-color: var(--error) !important;
            box-shadow: 0 0 0 4px rgba(239, 68, 68, 0.1) !important;
        }

        .shake {
            animation: shake 0.5s cubic-bezier(.36,.07,.19,.97) both;
        }

        @keyframes shake {
            10%, 90% { transform: translate3d(-1px, 0, 0); }
            20%, 80% { transform: translate3d(2px, 0, 0); }
            30%, 50%, 70% { transform: translate3d(-4px, 0, 0); }
            40%, 60% { transform: translate3d(4px, 0, 0); }
        }

        /* Neuro-Design: Focal Point Engineering */
        .otp-input:focus-visible {
            border-color: var(--primary);
            outline: none;
            background: white;
            box-shadow: 
                0 0 0 4px var(--primary),
                0 10px 20px rgba(255, 153, 51, 0.2);
            transform: translateY(-4px) scale(1.05);
            z-index: 10;
        }

        .resend-link {
            text-align: center;
            margin-top: 1.5rem;
            font-size: var(--font-small);
            color: var(--slate-600);
        }

        .resend-link a {
            color: var(--primary);
            text-decoration: none;
            font-weight: 700;
            pointer-events: none;
            opacity: 0.6;
            transition: all 0.3s;
            padding: 0.5rem;
            display: inline-block;
            min-height: 44px;
        }

        .resend-link a.active {
            pointer-events: auto;
            opacity: 1;
        }
        
        @media (hover: hover) {
            .resend-link a.active:hover {
                text-decoration: underline;
            }
        }

        .change-number {
            color: var(--slate-600);
            font-size: var(--font-small);
            text-decoration: none;
            font-weight: 500;
            transition: color 0.3s;
            display: inline-block;
            margin-top: 1rem;
            padding: 0.5rem;
            min-height: 44px;
        }

        @media (hover: hover) {
            .change-number:hover {
                color: var(--dark-slate);
                text-decoration: underline;
            }
        }

        /* Responsive Breakpoints */
        @media (max-width: 768px) {
            .login-container {
                padding: 6rem 1.5rem 3rem;
            }
            .login-card {
                padding: 2.5rem 2rem;
            }
        }

        @media (max-width: 480px) {
            .login-container {
                padding: 5rem 1rem 2rem;
            }
            .login-card {
                padding: 2rem 1rem;
                border-radius: 24px;
            }
            .otp-inputs {
                gap: 0.25rem;
            }
            .otp-inputs input {
                min-width: 35px;
            }
            .nav-container {
                padding: 1rem;
            }
            .back-link span {
                display: none; /* Hide text on very small screens */
            }
        }

        /* PWA Offline Toast */
        .offline-toast {
            position: fixed;
            bottom: -100px;
            left: 50%;
            transform: translateX(-50%);
            background: #b91c1c; /* var(--error) */
            color: white;
            padding: 0.75rem 1.5rem;
            border-radius: 99px;
            font-size: 0.9rem;
            font-weight: 600;
            box-shadow: 0 10px 15px -3px rgba(185, 28, 28, 0.4);
            z-index: 99999;
            transition: bottom 0.4s var(--spring);
        }
        .offline-toast.show {
            bottom: 30px;
        }