/* Reset & Base */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Dark Theme Colors */
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: #16161f;
    --bg-input: #1e1e2a;
    --bg-hover: #252533;
    
    /* Accent Colors */
    --accent: #8b5cf6;
    --accent-light: #a78bfa;
    --accent-dark: #7c3aed;
    --accent-glow: rgba(139, 92, 246, 0.4);
    
    /* Status Colors */
    --success: #10b981;
    --success-glow: rgba(16, 185, 129, 0.3);
    --error: #ef4444;
    --error-glow: rgba(239, 68, 68, 0.3);
    --warning: #f59e0b;
    --warning-glow: rgba(245, 158, 11, 0.2);
    
    /* Text Colors */
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    
    /* Border & Shadow */
    --border: #2a2a3a;
    --border-focus: var(--accent);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 40px var(--accent-glow);
    
    /* Sizing */
    --radius: 16px;
    --radius-sm: 10px;
    --radius-xs: 6px;
}

/* Animated Background */
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    -webkit-font-smoothing: antialiased;
    position: relative;
    overflow-x: hidden;
}

/* Animated gradient orbs */
body::before,
body::after {
    content: '';
    position: fixed;
    width: 600px;
    height: 600px;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.4;
    pointer-events: none;
    animation: float 20s ease-in-out infinite;
}

body::before {
    background: linear-gradient(135deg, #8b5cf6, #6366f1);
    top: -200px;
    left: -200px;
}

body::after {
    background: linear-gradient(135deg, #ec4899, #8b5cf6);
    bottom: -200px;
    right: -200px;
    animation-delay: -10s;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) scale(1); }
    25% { transform: translate(50px, 50px) scale(1.1); }
    50% { transform: translate(0, 100px) scale(0.95); }
    75% { transform: translate(-50px, 50px) scale(1.05); }
}

/* Container */
.container {
    width: 100%;
    max-width: 480px;
    position: relative;
    z-index: 1;
}

/* Card */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: clamp(24px, 6vw, 48px);
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
    backdrop-filter: blur(20px);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), var(--shadow-glow);
}

/* Animated border gradient */
.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), #ec4899, var(--accent));
    background-size: 200% 100%;
    animation: gradient-shift 3s ease-in-out infinite;
}

@keyframes gradient-shift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

/* Header */
.card-header {
    text-align: center;
    margin-bottom: clamp(20px, 4vw, 32px);
}

.logo {
    margin-bottom: 16px;
    animation: pulse-glow 2s ease-in-out infinite;
}

@keyframes pulse-glow {
    0%, 100% { filter: drop-shadow(0 0 8px var(--accent-glow)); }
    50% { filter: drop-shadow(0 0 20px var(--accent-glow)); }
}

.logo svg rect {
    fill: var(--accent);
}

h1 {
    font-size: clamp(1.4rem, 5vw, 1.75rem);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, var(--text-primary), var(--accent-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

h2 {
    font-size: clamp(1.2rem, 4vw, 1.5rem);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.subtitle {
    color: var(--text-secondary);
    font-size: clamp(0.85rem, 2.5vw, 0.95rem);
}

/* Warning Box */
.warning-box {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    background: linear-gradient(135deg, rgba(245, 158, 11, 0.15), rgba(245, 158, 11, 0.05));
    border: 1px solid rgba(245, 158, 11, 0.3);
    border-radius: var(--radius-sm);
    padding: 14px 16px;
    margin-top: 20px;
    font-size: clamp(0.8rem, 2.5vw, 0.85rem);
    color: #fbbf24;
    text-align: left;
    backdrop-filter: blur(10px);
}

.warning-box svg {
    flex-shrink: 0;
    color: #f59e0b;
    margin-top: 1px;
}

/* Steps Animation */
.step {
    animation: slideUp 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

.hidden {
    display: none !important;
}

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

/* Form */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.form-group input {
    width: 100%;
    padding: 14px 16px;
    font-size: 1rem;
    font-family: inherit;
    color: var(--text-primary);
    background: var(--bg-input);
    border: 2px solid var(--border);
    border-radius: var(--radius-sm);
    outline: none;
    transition: all 0.3s ease;
}

.form-group input::placeholder {
    color: var(--text-muted);
}

.form-group input:hover {
    border-color: var(--bg-hover);
    background: var(--bg-hover);
}

.form-group input:focus {
    border-color: var(--accent);
    background: var(--bg-input);
    box-shadow: 0 0 0 4px var(--accent-glow);
}

.form-group input.locked {
    background: var(--bg-secondary);
    color: var(--text-secondary);
    cursor: not-allowed;
    border-color: var(--border);
}

.form-group input.error {
    border-color: var(--error);
    box-shadow: 0 0 0 4px var(--error-glow);
}

.field-hint {
    display: block;
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-top: 6px;
}

.field-hint.warning {
    color: #fbbf24;
    font-weight: 500;
}

.field-error {
    display: block;
    font-size: 0.8rem;
    color: var(--error);
    margin-top: 6px;
    min-height: 1.2em;
}

/* OTP Section */
.otp-group {
    animation: slideUp 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.otp-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

.otp-wrapper input {
    font-family: 'SF Mono', 'Fira Code', monospace;
    font-size: 1.5rem;
    letter-spacing: 0.5em;
    text-align: center;
    padding-right: 70px;
}

.timer-badge {
    position: absolute;
    right: 12px;
    background: linear-gradient(135deg, var(--accent), var(--accent-dark));
    color: white;
    padding: 6px 12px;
    border-radius: var(--radius-xs);
    font-size: 0.85rem;
    font-weight: 600;
    box-shadow: 0 2px 8px var(--accent-glow);
}

.timer-badge.expired {
    background: linear-gradient(135deg, var(--error), #dc2626);
    box-shadow: 0 2px 8px var(--error-glow);
    animation: shake 0.5s ease-in-out;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-4px); }
    75% { transform: translateX(4px); }
}

/* Primary Button */
.btn-primary {
    width: 100%;
    padding: 16px 24px;
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    color: white;
    background: linear-gradient(135deg, var(--accent), var(--accent-dark));
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 16px var(--accent-glow);
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s ease;
}

.btn-primary:hover::before {
    left: 100%;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 24px var(--accent-glow);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-primary:disabled {
    background: var(--bg-hover);
    color: var(--text-muted);
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.btn-primary:disabled::before {
    display: none;
}

.btn-spinner {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* Resend Section */
.resend-section {
    text-align: center;
    margin-top: 16px;
}

.btn-link {
    background: none;
    border: none;
    color: var(--accent-light);
    font-size: 0.9rem;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    padding: 8px 16px;
    border-radius: var(--radius-xs);
    transition: all 0.2s ease;
}

.btn-link:hover:not(:disabled) {
    color: var(--accent);
    background: rgba(139, 92, 246, 0.1);
}

.btn-link:disabled {
    color: var(--text-muted);
    cursor: not-allowed;
}

/* Success State */
.success-content {
    text-align: center;
    padding: 20px 0;
}

.success-icon {
    margin-bottom: 24px;
    animation: success-bounce 0.6s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

.success-icon svg circle {
    fill: var(--success);
    filter: drop-shadow(0 0 20px var(--success-glow));
}

@keyframes success-bounce {
    0% { transform: scale(0); }
    50% { transform: scale(1.2); }
    100% { transform: scale(1); }
}

.details-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 20px;
    margin-top: 24px;
    text-align: left;
}

.detail-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
}

.detail-row:last-child {
    border-bottom: none;
}

.detail-label {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-weight: 500;
}

.detail-value {
    font-size: 0.95rem;
    color: var(--text-primary);
    font-weight: 600;
    text-align: right;
    word-break: break-word;
    max-width: 60%;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    padding: 14px 24px;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    font-weight: 500;
    color: white;
    background: var(--bg-card);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-md);
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s cubic-bezier(0.68, -0.55, 0.265, 1.55);
    z-index: 1000;
    max-width: calc(100% - 32px);
    text-align: center;
}

.toast.show {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.toast.success {
    background: linear-gradient(135deg, var(--success), #059669);
    border-color: var(--success);
    box-shadow: 0 4px 20px var(--success-glow);
}

.toast.error {
    background: linear-gradient(135deg, var(--error), #dc2626);
    border-color: var(--error);
    box-shadow: 0 4px 20px var(--error-glow);
}

.toast.info {
    background: linear-gradient(135deg, var(--accent), var(--accent-dark));
    border-color: var(--accent);
    box-shadow: 0 4px 20px var(--accent-glow);
}

/* Footer */
.footer-text {
    text-align: center;
    margin-top: 24px;
    font-size: 0.8rem;
    color: var(--text-muted);
    opacity: 0.7;
}

/* ================================
   RESPONSIVE BREAKPOINTS
   ================================ */

/* Large phones */
@media (max-width: 480px) {
    .card {
        border-radius: var(--radius-sm);
    }
    
    .otp-wrapper input {
        font-size: 1.25rem;
        letter-spacing: 0.3em;
    }
    
    .timer-badge {
        padding: 4px 10px;
        font-size: 0.8rem;
    }
    
    .detail-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 4px;
    }
    
    .detail-value {
        text-align: left;
        max-width: 100%;
    }
}

/* Small phones */
@media (max-width: 360px) {
    body {
        padding: 12px;
    }
    
    .card {
        padding: 20px;
    }
    
    h1 {
        font-size: 1.3rem;
    }
    
    .warning-box {
        flex-direction: column;
        gap: 8px;
    }
    
    .btn-primary {
        padding: 14px 20px;
    }
    
    .otp-wrapper input {
        font-size: 1.1rem;
        letter-spacing: 0.2em;
        padding-right: 60px;
    }
}

/* Tablets and up */
@media (min-width: 768px) {
    .container {
        max-width: 500px;
    }
    
    .card {
        padding: 48px;
    }
}

/* Large screens */
@media (min-width: 1024px) {
    body::before {
        width: 800px;
        height: 800px;
    }
    
    body::after {
        width: 700px;
        height: 700px;
    }
}

/* Landscape phones */
@media (max-height: 600px) and (orientation: landscape) {
    body {
        padding: 8px;
        align-items: flex-start;
        overflow-y: auto;
    }
    
    .card {
        padding: 24px;
    }
    
    .card-header {
        margin-bottom: 16px;
    }
    
    .logo {
        margin-bottom: 8px;
    }
    
    .logo svg {
        width: 32px;
        height: 32px;
    }
    
    .form-group {
        margin-bottom: 12px;
    }
    
    .warning-box {
        padding: 10px 12px;
        margin-top: 12px;
    }
}

/* Reduced motion preference */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    body::before, body::after {
        animation: none;
    }
}

/* High contrast mode */
@media (prefers-contrast: high) {
    :root {
        --border: #444;
        --text-primary: #fff;
        --text-secondary: #ccc;
    }
    
    .form-group input {
        border-width: 3px;
    }
}

/* WhatsApp Help Link */
.help-section {
    margin-top: 1.5rem;
    padding: 1rem;
    background: linear-gradient(135deg, rgba(37, 211, 102, 0.1), rgba(37, 211, 102, 0.05));
    border: 1px solid rgba(37, 211, 102, 0.3);
    border-radius: var(--radius-sm);
    text-align: center;
    animation: slideUp 0.3s ease;
}

.help-section p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 0.75rem;
}

.whatsapp-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: linear-gradient(135deg, #25d366, #128c7e);
    color: white;
    text-decoration: none;
    border-radius: var(--radius-xs);
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(37, 211, 102, 0.3);
}

.whatsapp-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(37, 211, 102, 0.4);
    background: linear-gradient(135deg, #2ee876, #15a589);
}

.whatsapp-link svg {
    flex-shrink: 0;
}

/* Print styles */
@media print {
    body {
        background: white;
    }
    
    body::before, body::after {
        display: none;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid #ccc;
    }
    
    .btn-primary, .resend-section, .toast {
        display: none;
    }
}