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

html, body {
    height: 100%;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.signup-form {
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 450px;
    animation: slideUp 0.6s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

h1 {
    text-align: center;
    color: #333;
    margin-bottom: 30px;
    font-size: 28px;
    font-weight: 600;
}

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

label {
    display: block;
    margin-bottom: 8px;
    color: #555;
    font-weight: 500;
    font-size: 14px;
}

input[type="text"],
input[type="tel"],
input[type="number"],
select {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid #e1e5e9;
    border-radius: 10px;
    font-size: 16px;
    transition: all 0.3s ease;
    background-color: #f8f9fa;
}

input[type="text"]:focus,
input[type="tel"]:focus,
input[type="number"]:focus,
select:focus {
    outline: none;
    border-color: #667eea;
    background-color: white;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.phone-input {
    display: flex;
    gap: 10px;
}

.country-code {
    flex: 0 0 140px;
}

#phoneNumber {
    flex: 1;
}

.otp-section {
    opacity: 0;
    transform: translateY(-10px);
    transition: all 0.3s ease;
}

.otp-section.show {
    opacity: 1;
    transform: translateY(0);
    display: block !important;
}

.button-group {
    margin: 30px 0 20px 0;
}

.btn {
    width: 100%;
    padding: 14px;
    border: none;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 10px;
}

.btn.primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.3);
}

.btn.primary:disabled {
    background: #ccc;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.btn.secondary {
    background: #28a745;
    color: white;
}

.btn.secondary:hover {
    background: #218838;
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(40, 167, 69, 0.3);
}

.message-area {
    padding: 12px;
    border-radius: 8px;
    text-align: center;
    font-size: 14px;
    font-weight: 500;
    min-height: 20px;
    transition: all 0.3s ease;
}

.message-area.success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.message-area.error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.message-area.info {
    background-color: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
}

/* Responsive Design */
@media (max-width: 480px) {
    .container {
        padding: 10px;
    }
    
    .signup-form {
        padding: 30px 20px;
    }
    
    h1 {
        font-size: 24px;
        margin-bottom: 25px;
    }
    
    .phone-input {
        flex-direction: column;
    }
    
    .country-code {
        flex: none;
    }
}

/* Loading animation for buttons */
.btn.loading {
    position: relative;
    color: transparent;
}

.btn.loading::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    top: 50%;
    left: 50%;
    margin-left: -10px;
    margin-top: -10px;
    border: 2px solid transparent;
    border-top-color: #ffffff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

/* Enhanced form validation styles */
input.error {
    border-color: #dc3545;
    background-color: #fff5f5;
}

input.success {
    border-color: #28a745;
    background-color: #f8fff8;
}

.field-error {
    color: #dc3545;
    font-size: 12px;
    margin-top: 5px;
    display: block;
}