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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #0f0f0f 0%, #1a1a1a 50%, #000000 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 400px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.auth-card {
    background: #1e1e1e;
    border: 1px solid #333;
    border-radius: 20px;
    padding: 40px 32px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
    position: relative;
    overflow: hidden;
}

.auth-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #ffffff, #888888);
}

.header {
    text-align: center;
    margin-bottom: 32px;
}

.header h1 {
    font-size: 28px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 8px;
}

.header p {
    color: #cccccc;
    font-size: 16px;
    font-weight: 400;
}

.step {
    display: none;
}

.step.active {
    display: block;
    animation: slideIn 0.3s ease-out;
}

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

.step h2 {
    font-size: 24px;
    font-weight: 600;
    color: #ffffff;
    margin-bottom: 8px;
    text-align: center;
}

.step p {
    color: #cccccc;
    font-size: 14px;
    text-align: center;
    margin-bottom: 24px;
    line-height: 1.5;
}

.input-group {
    margin-bottom: 24px;
}

.phone-input {
    display: flex;
    border: 2px solid #444;
    border-radius: 12px;
    overflow: hidden;
    transition: border-color 0.2s;
    background: #2a2a2a;
}

.phone-input:focus-within {
    border-color: #ffffff;
}

.country-select {
    background: #333;
    border: none;
    padding: 16px 12px;
    font-size: 14px;
    font-weight: 500;
    color: #ffffff;
    cursor: pointer;
    outline: none;
    min-width: 80px;
}

.country-select:focus {
    background: #444;
}

#phone-number {
    flex: 1;
    border: none;
    padding: 16px;
    font-size: 16px;
    outline: none;
    background: #2a2a2a;
    color: #ffffff;
}

#phone-number::placeholder {
    color: #888;
}

.otp-input {
    display: flex;
    gap: 8px;
    justify-content: center;
    margin-bottom: 8px;
}

.otp-digit {
    width: 48px;
    height: 56px;
    border: 2px solid #444;
    border-radius: 12px;
    text-align: center;
    font-size: 20px;
    font-weight: 600;
    color: #ffffff;
    background: #2a2a2a;
    outline: none;
    transition: all 0.2s;
}

.otp-digit:focus {
    border-color: #ffffff;
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.1);
}

.otp-digit.filled {
    border-color: #ffffff;
    background: #333;
}

.error-message {
    color: #ef4444;
    font-size: 14px;
    margin-top: 8px;
    text-align: center;
    min-height: 20px;
}

.primary-btn {
    width: 100%;
    background: linear-gradient(135deg, #ffffff 0%, #cccccc 100%);
    color: #000000;
    border: none;
    padding: 16px 24px;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    position: relative;
    overflow: hidden;
}

.primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(255, 255, 255, 0.2);
}

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

.primary-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.secondary-btn {
    width: 100%;
    background: transparent;
    color: #ffffff;
    border: 2px solid #444;
    padding: 14px 24px;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    margin-top: 16px;
}

.secondary-btn:hover {
    border-color: #ffffff;
    background: #333;
}

.link-btn {
    background: none;
    border: none;
    color: #ffffff;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    text-decoration: underline;
    padding: 0;
}

.link-btn:hover {
    color: #cccccc;
}

.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(0, 0, 0, 0.3);
    border-top: 2px solid black;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.hidden {
    display: none !important;
}

.resend-section {
    text-align: center;
    margin: 24px 0 16px;
}

.resend-section p {
    color: #cccccc;
    font-size: 14px;
    margin-bottom: 8px;
}

.timer {
    color: #cccccc;
    font-size: 14px;
}

.success-icon {
    text-align: center;
    margin-bottom: 24px;
}

.success-icon svg {
    animation: scaleIn 0.5s ease-out;
}

@keyframes scaleIn {
    0% {
        transform: scale(0);
    }
    50% {
        transform: scale(1.1);
    }
    100% {
        transform: scale(1);
    }
}

.success-message {
    font-size: 16px;
    color: #ffffff;
    text-align: center;
    margin-bottom: 32px;
    line-height: 1.6;
}

.next-steps {
    background: #2a2a2a;
    border: 1px solid #444;
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 24px;
}

.next-steps h3 {
    font-size: 16px;
    font-weight: 600;
    color: #ffffff;
    margin-bottom: 12px;
}

.next-steps ul {
    list-style: none;
    padding: 0;
}

.next-steps li {
    color: #cccccc;
    font-size: 14px;
    margin-bottom: 8px;
    padding-left: 20px;
    position: relative;
}

.next-steps li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #10b981;
    font-weight: bold;
}

.footer {
    text-align: center;
    color: rgba(255, 255, 255, 0.8);
    font-size: 14px;
}

/* Responsive Design */
@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }
    
    .auth-card {
        padding: 32px 24px;
    }
    
    .header h1 {
        font-size: 24px;
    }
    
    .step h2 {
        font-size: 20px;
    }
    
    .otp-digit {
        width: 40px;
        height: 48px;
        font-size: 18px;
    }
    
    .otp-input {
        gap: 6px;
    }
}

/* Focus states for accessibility */
.primary-btn:focus,
.secondary-btn:focus,
.link-btn:focus {
    outline: 2px solid #ffffff;
    outline-offset: 2px;
}

/* Animation for phone display */
#phone-display {
    font-weight: 600;
    color: #ffffff;
}